SemaDecl.cpp revision 5460d2b51965a53c5db537d432988f5e1d20af6f
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 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1063 1064 // FIXME: They should never return 0, fix that, delete this code. 1065 if (cfg == 0) 1066 return NeverFallThrough; 1067 // The CFG leaves in dead things, and we don't want to dead code paths to 1068 // confuse us, so we mark all live things first. 1069 std::queue<CFGBlock*> workq; 1070 llvm::BitVector live(cfg->getNumBlockIDs()); 1071 // Prep work queue 1072 workq.push(&cfg->getEntry()); 1073 // Solve 1074 while (!workq.empty()) { 1075 CFGBlock *item = workq.front(); 1076 workq.pop(); 1077 live.set(item->getBlockID()); 1078 for (CFGBlock::succ_iterator I=item->succ_begin(), 1079 E=item->succ_end(); 1080 I != E; 1081 ++I) { 1082 if ((*I) && !live[(*I)->getBlockID()]) { 1083 live.set((*I)->getBlockID()); 1084 workq.push(*I); 1085 } 1086 } 1087 } 1088 1089 // Now we know what is live, we check the live precessors of the exit block 1090 // and look for fall through paths, being careful to ignore normal returns, 1091 // and exceptional paths. 1092 bool HasLiveReturn = false; 1093 bool HasFakeEdge = false; 1094 bool HasPlainEdge = false; 1095 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1096 E = cfg->getExit().pred_end(); 1097 I != E; 1098 ++I) { 1099 CFGBlock& B = **I; 1100 if (!live[B.getBlockID()]) 1101 continue; 1102 if (B.size() == 0) { 1103 // A labeled empty statement, or the entry block... 1104 HasPlainEdge = true; 1105 continue; 1106 } 1107 Stmt *S = B[B.size()-1]; 1108 if (isa<ReturnStmt>(S)) { 1109 HasLiveReturn = true; 1110 continue; 1111 } 1112 if (isa<ObjCAtThrowStmt>(S)) { 1113 HasFakeEdge = true; 1114 continue; 1115 } 1116 if (isa<CXXThrowExpr>(S)) { 1117 HasFakeEdge = true; 1118 continue; 1119 } 1120 bool NoReturnEdge = false; 1121 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1122 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1123 if (CEE->getType().getNoReturnAttr()) { 1124 NoReturnEdge = true; 1125 HasFakeEdge = true; 1126 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1127 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1128 if (FD->hasAttr<NoReturnAttr>()) { 1129 NoReturnEdge = true; 1130 HasFakeEdge = true; 1131 } 1132 } 1133 } 1134 } 1135 // FIXME: Add noreturn message sends. 1136 if (NoReturnEdge == false) 1137 HasPlainEdge = true; 1138 } 1139 if (!HasPlainEdge) 1140 return NeverFallThrough; 1141 if (HasFakeEdge || HasLiveReturn) 1142 return MaybeFallThrough; 1143 // This says AlwaysFallThrough for calls to functions that are not marked 1144 // noreturn, that don't return. If people would like this warning to be more 1145 // accurate, such functions should be marked as noreturn. 1146 return AlwaysFallThrough; 1147} 1148 1149/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1150/// function that should return a value. Check that we don't fall off the end 1151/// of a noreturn function. We assume that functions and blocks not marked 1152/// noreturn will return. 1153void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1154 // FIXME: Would be nice if we had a better way to control cascading errors, 1155 // but for now, avoid them. The problem is that when Parse sees: 1156 // int foo() { return a; } 1157 // The return is eaten and the Sema code sees just: 1158 // int foo() { } 1159 // which this code would then warn about. 1160 if (getDiagnostics().hasErrorOccurred()) 1161 return; 1162 bool ReturnsVoid = false; 1163 bool HasNoReturn = false; 1164 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1165 // If the result type of the function is a dependent type, we don't know 1166 // whether it will be void or not, so don't 1167 if (FD->getResultType()->isDependentType()) 1168 return; 1169 if (FD->getResultType()->isVoidType()) 1170 ReturnsVoid = true; 1171 if (FD->hasAttr<NoReturnAttr>()) 1172 HasNoReturn = true; 1173 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1174 if (MD->getResultType()->isVoidType()) 1175 ReturnsVoid = true; 1176 if (MD->hasAttr<NoReturnAttr>()) 1177 HasNoReturn = true; 1178 } 1179 1180 // Short circuit for compilation speed. 1181 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1182 == Diagnostic::Ignored || ReturnsVoid) 1183 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1184 == Diagnostic::Ignored || !HasNoReturn) 1185 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1186 == Diagnostic::Ignored || !ReturnsVoid)) 1187 return; 1188 // FIXME: Function try block 1189 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1190 switch (CheckFallThrough(Body)) { 1191 case MaybeFallThrough: 1192 if (HasNoReturn) 1193 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1194 else if (!ReturnsVoid) 1195 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1196 break; 1197 case AlwaysFallThrough: 1198 if (HasNoReturn) 1199 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1200 else if (!ReturnsVoid) 1201 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1202 break; 1203 case NeverFallThrough: 1204 if (ReturnsVoid) 1205 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1206 break; 1207 } 1208 } 1209} 1210 1211/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1212/// that should return a value. Check that we don't fall off the end of a 1213/// noreturn block. We assume that functions and blocks not marked noreturn 1214/// will return. 1215void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1216 // FIXME: Would be nice if we had a better way to control cascading errors, 1217 // but for now, avoid them. The problem is that when Parse sees: 1218 // int foo() { return a; } 1219 // The return is eaten and the Sema code sees just: 1220 // int foo() { } 1221 // which this code would then warn about. 1222 if (getDiagnostics().hasErrorOccurred()) 1223 return; 1224 bool ReturnsVoid = false; 1225 bool HasNoReturn = false; 1226 if (const FunctionType *FT = BlockTy->getPointeeType()->getAs<FunctionType>()) { 1227 if (FT->getResultType()->isVoidType()) 1228 ReturnsVoid = true; 1229 if (FT->getNoReturnAttr()) 1230 HasNoReturn = true; 1231 } 1232 1233 // Short circuit for compilation speed. 1234 if (ReturnsVoid 1235 && !HasNoReturn 1236 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1237 == Diagnostic::Ignored || !ReturnsVoid)) 1238 return; 1239 // FIXME: Funtion try block 1240 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1241 switch (CheckFallThrough(Body)) { 1242 case MaybeFallThrough: 1243 if (HasNoReturn) 1244 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1245 else if (!ReturnsVoid) 1246 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1247 break; 1248 case AlwaysFallThrough: 1249 if (HasNoReturn) 1250 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1251 else if (!ReturnsVoid) 1252 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1253 break; 1254 case NeverFallThrough: 1255 if (ReturnsVoid) 1256 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1257 break; 1258 } 1259 } 1260} 1261 1262/// CheckParmsForFunctionDef - Check that the parameters of the given 1263/// function are appropriate for the definition of a function. This 1264/// takes care of any checks that cannot be performed on the 1265/// declaration itself, e.g., that the types of each of the function 1266/// parameters are complete. 1267bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1268 bool HasInvalidParm = false; 1269 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1270 ParmVarDecl *Param = FD->getParamDecl(p); 1271 1272 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1273 // function declarator that is part of a function definition of 1274 // that function shall not have incomplete type. 1275 // 1276 // This is also C++ [dcl.fct]p6. 1277 if (!Param->isInvalidDecl() && 1278 RequireCompleteType(Param->getLocation(), Param->getType(), 1279 diag::err_typecheck_decl_incomplete_type)) { 1280 Param->setInvalidDecl(); 1281 HasInvalidParm = true; 1282 } 1283 1284 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1285 // declaration of each parameter shall include an identifier. 1286 if (Param->getIdentifier() == 0 && 1287 !Param->isImplicit() && 1288 !getLangOptions().CPlusPlus) 1289 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1290 } 1291 1292 return HasInvalidParm; 1293} 1294 1295/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1296/// no declarator (e.g. "struct foo;") is parsed. 1297Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1298 // FIXME: Error on auto/register at file scope 1299 // FIXME: Error on inline/virtual/explicit 1300 // FIXME: Error on invalid restrict 1301 // FIXME: Warn on useless __thread 1302 // FIXME: Warn on useless const/volatile 1303 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1304 // FIXME: Warn on useless attributes 1305 Decl *TagD = 0; 1306 TagDecl *Tag = 0; 1307 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1308 DS.getTypeSpecType() == DeclSpec::TST_struct || 1309 DS.getTypeSpecType() == DeclSpec::TST_union || 1310 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1311 TagD = static_cast<Decl *>(DS.getTypeRep()); 1312 1313 if (!TagD) // We probably had an error 1314 return DeclPtrTy(); 1315 1316 // Note that the above type specs guarantee that the 1317 // type rep is a Decl, whereas in many of the others 1318 // it's a Type. 1319 Tag = dyn_cast<TagDecl>(TagD); 1320 } 1321 1322 if (DS.isFriendSpecified()) { 1323 // If we're dealing with a class template decl, assume that the 1324 // template routines are handling it. 1325 if (TagD && isa<ClassTemplateDecl>(TagD)) 1326 return DeclPtrTy(); 1327 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1328 } 1329 1330 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1331 if (!Record->getDeclName() && Record->isDefinition() && 1332 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1333 if (getLangOptions().CPlusPlus || 1334 Record->getDeclContext()->isRecord()) 1335 return BuildAnonymousStructOrUnion(S, DS, Record); 1336 1337 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1338 << DS.getSourceRange(); 1339 } 1340 1341 // Microsoft allows unnamed struct/union fields. Don't complain 1342 // about them. 1343 // FIXME: Should we support Microsoft's extensions in this area? 1344 if (Record->getDeclName() && getLangOptions().Microsoft) 1345 return DeclPtrTy::make(Tag); 1346 } 1347 1348 if (!DS.isMissingDeclaratorOk() && 1349 DS.getTypeSpecType() != DeclSpec::TST_error) { 1350 // Warn about typedefs of enums without names, since this is an 1351 // extension in both Microsoft an GNU. 1352 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1353 Tag && isa<EnumDecl>(Tag)) { 1354 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1355 << DS.getSourceRange(); 1356 return DeclPtrTy::make(Tag); 1357 } 1358 1359 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1360 << DS.getSourceRange(); 1361 return DeclPtrTy(); 1362 } 1363 1364 return DeclPtrTy::make(Tag); 1365} 1366 1367/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1368/// anonymous struct or union AnonRecord into the owning context Owner 1369/// and scope S. This routine will be invoked just after we realize 1370/// that an unnamed union or struct is actually an anonymous union or 1371/// struct, e.g., 1372/// 1373/// @code 1374/// union { 1375/// int i; 1376/// float f; 1377/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1378/// // f into the surrounding scope.x 1379/// @endcode 1380/// 1381/// This routine is recursive, injecting the names of nested anonymous 1382/// structs/unions into the owning context and scope as well. 1383bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1384 RecordDecl *AnonRecord) { 1385 bool Invalid = false; 1386 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1387 FEnd = AnonRecord->field_end(); 1388 F != FEnd; ++F) { 1389 if ((*F)->getDeclName()) { 1390 LookupResult R; 1391 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1392 LookupOrdinaryName, true); 1393 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1394 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1395 // C++ [class.union]p2: 1396 // The names of the members of an anonymous union shall be 1397 // distinct from the names of any other entity in the 1398 // scope in which the anonymous union is declared. 1399 unsigned diagKind 1400 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1401 : diag::err_anonymous_struct_member_redecl; 1402 Diag((*F)->getLocation(), diagKind) 1403 << (*F)->getDeclName(); 1404 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1405 Invalid = true; 1406 } else { 1407 // C++ [class.union]p2: 1408 // For the purpose of name lookup, after the anonymous union 1409 // definition, the members of the anonymous union are 1410 // considered to have been defined in the scope in which the 1411 // anonymous union is declared. 1412 Owner->makeDeclVisibleInContext(*F); 1413 S->AddDecl(DeclPtrTy::make(*F)); 1414 IdResolver.AddDecl(*F); 1415 } 1416 } else if (const RecordType *InnerRecordType 1417 = (*F)->getType()->getAs<RecordType>()) { 1418 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1419 if (InnerRecord->isAnonymousStructOrUnion()) 1420 Invalid = Invalid || 1421 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1422 } 1423 } 1424 1425 return Invalid; 1426} 1427 1428/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1429/// anonymous structure or union. Anonymous unions are a C++ feature 1430/// (C++ [class.union]) and a GNU C extension; anonymous structures 1431/// are a GNU C and GNU C++ extension. 1432Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1433 RecordDecl *Record) { 1434 DeclContext *Owner = Record->getDeclContext(); 1435 1436 // Diagnose whether this anonymous struct/union is an extension. 1437 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1438 Diag(Record->getLocation(), diag::ext_anonymous_union); 1439 else if (!Record->isUnion()) 1440 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1441 1442 // C and C++ require different kinds of checks for anonymous 1443 // structs/unions. 1444 bool Invalid = false; 1445 if (getLangOptions().CPlusPlus) { 1446 const char* PrevSpec = 0; 1447 unsigned DiagID; 1448 // C++ [class.union]p3: 1449 // Anonymous unions declared in a named namespace or in the 1450 // global namespace shall be declared static. 1451 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1452 (isa<TranslationUnitDecl>(Owner) || 1453 (isa<NamespaceDecl>(Owner) && 1454 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1455 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1456 Invalid = true; 1457 1458 // Recover by adding 'static'. 1459 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1460 PrevSpec, DiagID); 1461 } 1462 // C++ [class.union]p3: 1463 // A storage class is not allowed in a declaration of an 1464 // anonymous union in a class scope. 1465 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1466 isa<RecordDecl>(Owner)) { 1467 Diag(DS.getStorageClassSpecLoc(), 1468 diag::err_anonymous_union_with_storage_spec); 1469 Invalid = true; 1470 1471 // Recover by removing the storage specifier. 1472 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1473 PrevSpec, DiagID); 1474 } 1475 1476 // C++ [class.union]p2: 1477 // The member-specification of an anonymous union shall only 1478 // define non-static data members. [Note: nested types and 1479 // functions cannot be declared within an anonymous union. ] 1480 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1481 MemEnd = Record->decls_end(); 1482 Mem != MemEnd; ++Mem) { 1483 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1484 // C++ [class.union]p3: 1485 // An anonymous union shall not have private or protected 1486 // members (clause 11). 1487 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1488 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1489 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1490 Invalid = true; 1491 } 1492 } else if ((*Mem)->isImplicit()) { 1493 // Any implicit members are fine. 1494 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1495 // This is a type that showed up in an 1496 // elaborated-type-specifier inside the anonymous struct or 1497 // union, but which actually declares a type outside of the 1498 // anonymous struct or union. It's okay. 1499 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1500 if (!MemRecord->isAnonymousStructOrUnion() && 1501 MemRecord->getDeclName()) { 1502 // This is a nested type declaration. 1503 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1504 << (int)Record->isUnion(); 1505 Invalid = true; 1506 } 1507 } else { 1508 // We have something that isn't a non-static data 1509 // member. Complain about it. 1510 unsigned DK = diag::err_anonymous_record_bad_member; 1511 if (isa<TypeDecl>(*Mem)) 1512 DK = diag::err_anonymous_record_with_type; 1513 else if (isa<FunctionDecl>(*Mem)) 1514 DK = diag::err_anonymous_record_with_function; 1515 else if (isa<VarDecl>(*Mem)) 1516 DK = diag::err_anonymous_record_with_static; 1517 Diag((*Mem)->getLocation(), DK) 1518 << (int)Record->isUnion(); 1519 Invalid = true; 1520 } 1521 } 1522 } 1523 1524 if (!Record->isUnion() && !Owner->isRecord()) { 1525 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1526 << (int)getLangOptions().CPlusPlus; 1527 Invalid = true; 1528 } 1529 1530 // Create a declaration for this anonymous struct/union. 1531 NamedDecl *Anon = 0; 1532 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1533 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1534 /*IdentifierInfo=*/0, 1535 Context.getTypeDeclType(Record), 1536 // FIXME: Type source info. 1537 /*DInfo=*/0, 1538 /*BitWidth=*/0, /*Mutable=*/false); 1539 Anon->setAccess(AS_public); 1540 if (getLangOptions().CPlusPlus) 1541 FieldCollector->Add(cast<FieldDecl>(Anon)); 1542 } else { 1543 VarDecl::StorageClass SC; 1544 switch (DS.getStorageClassSpec()) { 1545 default: assert(0 && "Unknown storage class!"); 1546 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1547 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1548 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1549 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1550 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1551 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1552 case DeclSpec::SCS_mutable: 1553 // mutable can only appear on non-static class members, so it's always 1554 // an error here 1555 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1556 Invalid = true; 1557 SC = VarDecl::None; 1558 break; 1559 } 1560 1561 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1562 /*IdentifierInfo=*/0, 1563 Context.getTypeDeclType(Record), 1564 // FIXME: Type source info. 1565 /*DInfo=*/0, 1566 SC); 1567 } 1568 Anon->setImplicit(); 1569 1570 // Add the anonymous struct/union object to the current 1571 // context. We'll be referencing this object when we refer to one of 1572 // its members. 1573 Owner->addDecl(Anon); 1574 1575 // Inject the members of the anonymous struct/union into the owning 1576 // context and into the identifier resolver chain for name lookup 1577 // purposes. 1578 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1579 Invalid = true; 1580 1581 // Mark this as an anonymous struct/union type. Note that we do not 1582 // do this until after we have already checked and injected the 1583 // members of this anonymous struct/union type, because otherwise 1584 // the members could be injected twice: once by DeclContext when it 1585 // builds its lookup table, and once by 1586 // InjectAnonymousStructOrUnionMembers. 1587 Record->setAnonymousStructOrUnion(true); 1588 1589 if (Invalid) 1590 Anon->setInvalidDecl(); 1591 1592 return DeclPtrTy::make(Anon); 1593} 1594 1595 1596/// GetNameForDeclarator - Determine the full declaration name for the 1597/// given Declarator. 1598DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1599 switch (D.getKind()) { 1600 case Declarator::DK_Abstract: 1601 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1602 return DeclarationName(); 1603 1604 case Declarator::DK_Normal: 1605 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1606 return DeclarationName(D.getIdentifier()); 1607 1608 case Declarator::DK_Constructor: { 1609 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1610 return Context.DeclarationNames.getCXXConstructorName( 1611 Context.getCanonicalType(Ty)); 1612 } 1613 1614 case Declarator::DK_Destructor: { 1615 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1616 return Context.DeclarationNames.getCXXDestructorName( 1617 Context.getCanonicalType(Ty)); 1618 } 1619 1620 case Declarator::DK_Conversion: { 1621 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1622 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1623 return Context.DeclarationNames.getCXXConversionFunctionName( 1624 Context.getCanonicalType(Ty)); 1625 } 1626 1627 case Declarator::DK_Operator: 1628 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1629 return Context.DeclarationNames.getCXXOperatorName( 1630 D.getOverloadedOperator()); 1631 1632 case Declarator::DK_TemplateId: { 1633 TemplateName Name 1634 = TemplateName::getFromVoidPointer(D.getTemplateId()->Template); 1635 if (TemplateDecl *Template = Name.getAsTemplateDecl()) 1636 return Template->getDeclName(); 1637 if (OverloadedFunctionDecl *Ovl = Name.getAsOverloadedFunctionDecl()) 1638 return Ovl->getDeclName(); 1639 1640 return DeclarationName(); 1641 } 1642 } 1643 1644 assert(false && "Unknown name kind"); 1645 return DeclarationName(); 1646} 1647 1648/// isNearlyMatchingFunction - Determine whether the C++ functions 1649/// Declaration and Definition are "nearly" matching. This heuristic 1650/// is used to improve diagnostics in the case where an out-of-line 1651/// function definition doesn't match any declaration within 1652/// the class or namespace. 1653static bool isNearlyMatchingFunction(ASTContext &Context, 1654 FunctionDecl *Declaration, 1655 FunctionDecl *Definition) { 1656 if (Declaration->param_size() != Definition->param_size()) 1657 return false; 1658 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1659 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1660 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1661 1662 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1663 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1664 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1665 return false; 1666 } 1667 1668 return true; 1669} 1670 1671Sema::DeclPtrTy 1672Sema::HandleDeclarator(Scope *S, Declarator &D, 1673 MultiTemplateParamsArg TemplateParamLists, 1674 bool IsFunctionDefinition) { 1675 DeclarationName Name = GetNameForDeclarator(D); 1676 1677 // All of these full declarators require an identifier. If it doesn't have 1678 // one, the ParsedFreeStandingDeclSpec action should be used. 1679 if (!Name) { 1680 if (!D.isInvalidType()) // Reject this if we think it is valid. 1681 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1682 diag::err_declarator_need_ident) 1683 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1684 return DeclPtrTy(); 1685 } 1686 1687 // The scope passed in may not be a decl scope. Zip up the scope tree until 1688 // we find one that is. 1689 while ((S->getFlags() & Scope::DeclScope) == 0 || 1690 (S->getFlags() & Scope::TemplateParamScope) != 0) 1691 S = S->getParent(); 1692 1693 // If this is an out-of-line definition of a member of a class template 1694 // or class template partial specialization, we may need to rebuild the 1695 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1696 // for more information. 1697 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1698 // handle expressions properly. 1699 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1700 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1701 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1702 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1703 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1704 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1705 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1706 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1707 // FIXME: Preserve type source info. 1708 QualType T = GetTypeFromParser(DS.getTypeRep()); 1709 EnterDeclaratorContext(S, DC); 1710 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1711 ExitDeclaratorContext(S); 1712 if (T.isNull()) 1713 return DeclPtrTy(); 1714 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1715 } 1716 } 1717 1718 DeclContext *DC; 1719 NamedDecl *PrevDecl; 1720 NamedDecl *New; 1721 1722 DeclaratorInfo *DInfo = 0; 1723 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1724 1725 // See if this is a redefinition of a variable in the same scope. 1726 if (D.getCXXScopeSpec().isInvalid()) { 1727 DC = CurContext; 1728 PrevDecl = 0; 1729 D.setInvalidType(); 1730 } else if (!D.getCXXScopeSpec().isSet()) { 1731 LookupNameKind NameKind = LookupOrdinaryName; 1732 1733 // If the declaration we're planning to build will be a function 1734 // or object with linkage, then look for another declaration with 1735 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1736 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1737 /* Do nothing*/; 1738 else if (R->isFunctionType()) { 1739 if (CurContext->isFunctionOrMethod() || 1740 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1741 NameKind = LookupRedeclarationWithLinkage; 1742 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1743 NameKind = LookupRedeclarationWithLinkage; 1744 else if (CurContext->getLookupContext()->isTranslationUnit() && 1745 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1746 NameKind = LookupRedeclarationWithLinkage; 1747 1748 DC = CurContext; 1749 LookupResult R; 1750 LookupName(R, S, Name, NameKind, true, 1751 NameKind == LookupRedeclarationWithLinkage, 1752 D.getIdentifierLoc()); 1753 PrevDecl = R.getAsSingleDecl(Context); 1754 } else { // Something like "int foo::x;" 1755 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1756 1757 if (!DC) { 1758 // If we could not compute the declaration context, it's because the 1759 // declaration context is dependent but does not refer to a class, 1760 // class template, or class template partial specialization. Complain 1761 // and return early, to avoid the coming semantic disaster. 1762 Diag(D.getIdentifierLoc(), 1763 diag::err_template_qualified_declarator_no_match) 1764 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1765 << D.getCXXScopeSpec().getRange(); 1766 return DeclPtrTy(); 1767 } 1768 1769 if (!DC->isDependentContext() && 1770 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1771 return DeclPtrTy(); 1772 1773 LookupResult Res; 1774 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1775 PrevDecl = Res.getAsSingleDecl(Context); 1776 1777 // C++ 7.3.1.2p2: 1778 // Members (including explicit specializations of templates) of a named 1779 // namespace can also be defined outside that namespace by explicit 1780 // qualification of the name being defined, provided that the entity being 1781 // defined was already declared in the namespace and the definition appears 1782 // after the point of declaration in a namespace that encloses the 1783 // declarations namespace. 1784 // 1785 // Note that we only check the context at this point. We don't yet 1786 // have enough information to make sure that PrevDecl is actually 1787 // the declaration we want to match. For example, given: 1788 // 1789 // class X { 1790 // void f(); 1791 // void f(float); 1792 // }; 1793 // 1794 // void X::f(int) { } // ill-formed 1795 // 1796 // In this case, PrevDecl will point to the overload set 1797 // containing the two f's declared in X, but neither of them 1798 // matches. 1799 1800 // First check whether we named the global scope. 1801 if (isa<TranslationUnitDecl>(DC)) { 1802 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1803 << Name << D.getCXXScopeSpec().getRange(); 1804 } else if (!CurContext->Encloses(DC)) { 1805 // The qualifying scope doesn't enclose the original declaration. 1806 // Emit diagnostic based on current scope. 1807 SourceLocation L = D.getIdentifierLoc(); 1808 SourceRange R = D.getCXXScopeSpec().getRange(); 1809 if (isa<FunctionDecl>(CurContext)) 1810 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1811 else 1812 Diag(L, diag::err_invalid_declarator_scope) 1813 << Name << cast<NamedDecl>(DC) << R; 1814 D.setInvalidType(); 1815 } 1816 } 1817 1818 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1819 // Maybe we will complain about the shadowed template parameter. 1820 if (!D.isInvalidType()) 1821 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1822 D.setInvalidType(); 1823 1824 // Just pretend that we didn't see the previous declaration. 1825 PrevDecl = 0; 1826 } 1827 1828 // In C++, the previous declaration we find might be a tag type 1829 // (class or enum). In this case, the new declaration will hide the 1830 // tag type. Note that this does does not apply if we're declaring a 1831 // typedef (C++ [dcl.typedef]p4). 1832 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1833 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1834 PrevDecl = 0; 1835 1836 bool Redeclaration = false; 1837 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1838 if (TemplateParamLists.size()) { 1839 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1840 return DeclPtrTy(); 1841 } 1842 1843 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1844 } else if (R->isFunctionType()) { 1845 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1846 move(TemplateParamLists), 1847 IsFunctionDefinition, Redeclaration); 1848 } else { 1849 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1850 move(TemplateParamLists), 1851 Redeclaration); 1852 } 1853 1854 if (New == 0) 1855 return DeclPtrTy(); 1856 1857 // If this has an identifier and is not an invalid redeclaration or 1858 // function template specialization, add it to the scope stack. 1859 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1860 !(isa<FunctionDecl>(New) && 1861 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1862 PushOnScopeChains(New, S); 1863 1864 return DeclPtrTy::make(New); 1865} 1866 1867/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1868/// types into constant array types in certain situations which would otherwise 1869/// be errors (for GCC compatibility). 1870static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1871 ASTContext &Context, 1872 bool &SizeIsNegative) { 1873 // This method tries to turn a variable array into a constant 1874 // array even when the size isn't an ICE. This is necessary 1875 // for compatibility with code that depends on gcc's buggy 1876 // constant expression folding, like struct {char x[(int)(char*)2];} 1877 SizeIsNegative = false; 1878 1879 QualifierCollector Qs; 1880 const Type *Ty = Qs.strip(T); 1881 1882 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1883 QualType Pointee = PTy->getPointeeType(); 1884 QualType FixedType = 1885 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1886 if (FixedType.isNull()) return FixedType; 1887 FixedType = Context.getPointerType(FixedType); 1888 return Qs.apply(FixedType); 1889 } 1890 1891 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1892 if (!VLATy) 1893 return QualType(); 1894 // FIXME: We should probably handle this case 1895 if (VLATy->getElementType()->isVariablyModifiedType()) 1896 return QualType(); 1897 1898 Expr::EvalResult EvalResult; 1899 if (!VLATy->getSizeExpr() || 1900 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1901 !EvalResult.Val.isInt()) 1902 return QualType(); 1903 1904 llvm::APSInt &Res = EvalResult.Val.getInt(); 1905 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1906 // TODO: preserve the size expression in declarator info 1907 return Context.getConstantArrayType(VLATy->getElementType(), 1908 Res, ArrayType::Normal, 0); 1909 } 1910 1911 SizeIsNegative = true; 1912 return QualType(); 1913} 1914 1915/// \brief Register the given locally-scoped external C declaration so 1916/// that it can be found later for redeclarations 1917void 1918Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1919 Scope *S) { 1920 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1921 "Decl is not a locally-scoped decl!"); 1922 // Note that we have a locally-scoped external with this name. 1923 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1924 1925 if (!PrevDecl) 1926 return; 1927 1928 // If there was a previous declaration of this variable, it may be 1929 // in our identifier chain. Update the identifier chain with the new 1930 // declaration. 1931 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1932 // The previous declaration was found on the identifer resolver 1933 // chain, so remove it from its scope. 1934 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1935 S = S->getParent(); 1936 1937 if (S) 1938 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1939 } 1940} 1941 1942/// \brief Diagnose function specifiers on a declaration of an identifier that 1943/// does not identify a function. 1944void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1945 // FIXME: We should probably indicate the identifier in question to avoid 1946 // confusion for constructs like "inline int a(), b;" 1947 if (D.getDeclSpec().isInlineSpecified()) 1948 Diag(D.getDeclSpec().getInlineSpecLoc(), 1949 diag::err_inline_non_function); 1950 1951 if (D.getDeclSpec().isVirtualSpecified()) 1952 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1953 diag::err_virtual_non_function); 1954 1955 if (D.getDeclSpec().isExplicitSpecified()) 1956 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1957 diag::err_explicit_non_function); 1958} 1959 1960NamedDecl* 1961Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1962 QualType R, DeclaratorInfo *DInfo, 1963 NamedDecl* PrevDecl, bool &Redeclaration) { 1964 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1965 if (D.getCXXScopeSpec().isSet()) { 1966 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1967 << D.getCXXScopeSpec().getRange(); 1968 D.setInvalidType(); 1969 // Pretend we didn't see the scope specifier. 1970 DC = 0; 1971 } 1972 1973 if (getLangOptions().CPlusPlus) { 1974 // Check that there are no default arguments (C++ only). 1975 CheckExtraCXXDefaultArguments(D); 1976 } 1977 1978 DiagnoseFunctionSpecifiers(D); 1979 1980 if (D.getDeclSpec().isThreadSpecified()) 1981 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1982 1983 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1984 if (!NewTD) return 0; 1985 1986 if (D.isInvalidType()) 1987 NewTD->setInvalidDecl(); 1988 1989 // Handle attributes prior to checking for duplicates in MergeVarDecl 1990 ProcessDeclAttributes(S, NewTD, D); 1991 // Merge the decl with the existing one if appropriate. If the decl is 1992 // in an outer scope, it isn't the same thing. 1993 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1994 Redeclaration = true; 1995 MergeTypeDefDecl(NewTD, PrevDecl); 1996 } 1997 1998 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1999 // then it shall have block scope. 2000 QualType T = NewTD->getUnderlyingType(); 2001 if (T->isVariablyModifiedType()) { 2002 CurFunctionNeedsScopeChecking = true; 2003 2004 if (S->getFnParent() == 0) { 2005 bool SizeIsNegative; 2006 QualType FixedTy = 2007 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2008 if (!FixedTy.isNull()) { 2009 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2010 NewTD->setUnderlyingType(FixedTy); 2011 } else { 2012 if (SizeIsNegative) 2013 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2014 else if (T->isVariableArrayType()) 2015 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2016 else 2017 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2018 NewTD->setInvalidDecl(); 2019 } 2020 } 2021 } 2022 2023 // If this is the C FILE type, notify the AST context. 2024 if (IdentifierInfo *II = NewTD->getIdentifier()) 2025 if (!NewTD->isInvalidDecl() && 2026 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2027 if (II->isStr("FILE")) 2028 Context.setFILEDecl(NewTD); 2029 else if (II->isStr("jmp_buf")) 2030 Context.setjmp_bufDecl(NewTD); 2031 else if (II->isStr("sigjmp_buf")) 2032 Context.setsigjmp_bufDecl(NewTD); 2033 } 2034 2035 return NewTD; 2036} 2037 2038/// \brief Determines whether the given declaration is an out-of-scope 2039/// previous declaration. 2040/// 2041/// This routine should be invoked when name lookup has found a 2042/// previous declaration (PrevDecl) that is not in the scope where a 2043/// new declaration by the same name is being introduced. If the new 2044/// declaration occurs in a local scope, previous declarations with 2045/// linkage may still be considered previous declarations (C99 2046/// 6.2.2p4-5, C++ [basic.link]p6). 2047/// 2048/// \param PrevDecl the previous declaration found by name 2049/// lookup 2050/// 2051/// \param DC the context in which the new declaration is being 2052/// declared. 2053/// 2054/// \returns true if PrevDecl is an out-of-scope previous declaration 2055/// for a new delcaration with the same name. 2056static bool 2057isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2058 ASTContext &Context) { 2059 if (!PrevDecl) 2060 return 0; 2061 2062 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2063 // case we need to check each of the overloaded functions. 2064 if (!PrevDecl->hasLinkage()) 2065 return false; 2066 2067 if (Context.getLangOptions().CPlusPlus) { 2068 // C++ [basic.link]p6: 2069 // If there is a visible declaration of an entity with linkage 2070 // having the same name and type, ignoring entities declared 2071 // outside the innermost enclosing namespace scope, the block 2072 // scope declaration declares that same entity and receives the 2073 // linkage of the previous declaration. 2074 DeclContext *OuterContext = DC->getLookupContext(); 2075 if (!OuterContext->isFunctionOrMethod()) 2076 // This rule only applies to block-scope declarations. 2077 return false; 2078 else { 2079 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2080 if (PrevOuterContext->isRecord()) 2081 // We found a member function: ignore it. 2082 return false; 2083 else { 2084 // Find the innermost enclosing namespace for the new and 2085 // previous declarations. 2086 while (!OuterContext->isFileContext()) 2087 OuterContext = OuterContext->getParent(); 2088 while (!PrevOuterContext->isFileContext()) 2089 PrevOuterContext = PrevOuterContext->getParent(); 2090 2091 // The previous declaration is in a different namespace, so it 2092 // isn't the same function. 2093 if (OuterContext->getPrimaryContext() != 2094 PrevOuterContext->getPrimaryContext()) 2095 return false; 2096 } 2097 } 2098 } 2099 2100 return true; 2101} 2102 2103NamedDecl* 2104Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2105 QualType R, DeclaratorInfo *DInfo, 2106 NamedDecl* PrevDecl, 2107 MultiTemplateParamsArg TemplateParamLists, 2108 bool &Redeclaration) { 2109 DeclarationName Name = GetNameForDeclarator(D); 2110 2111 // Check that there are no default arguments (C++ only). 2112 if (getLangOptions().CPlusPlus) 2113 CheckExtraCXXDefaultArguments(D); 2114 2115 VarDecl *NewVD; 2116 VarDecl::StorageClass SC; 2117 switch (D.getDeclSpec().getStorageClassSpec()) { 2118 default: assert(0 && "Unknown storage class!"); 2119 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2120 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2121 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2122 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2123 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2124 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2125 case DeclSpec::SCS_mutable: 2126 // mutable can only appear on non-static class members, so it's always 2127 // an error here 2128 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2129 D.setInvalidType(); 2130 SC = VarDecl::None; 2131 break; 2132 } 2133 2134 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2135 if (!II) { 2136 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2137 << Name.getAsString(); 2138 return 0; 2139 } 2140 2141 DiagnoseFunctionSpecifiers(D); 2142 2143 if (!DC->isRecord() && S->getFnParent() == 0) { 2144 // C99 6.9p2: The storage-class specifiers auto and register shall not 2145 // appear in the declaration specifiers in an external declaration. 2146 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2147 2148 // If this is a register variable with an asm label specified, then this 2149 // is a GNU extension. 2150 if (SC == VarDecl::Register && D.getAsmLabel()) 2151 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2152 else 2153 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2154 D.setInvalidType(); 2155 } 2156 } 2157 if (DC->isRecord() && !CurContext->isRecord()) { 2158 // This is an out-of-line definition of a static data member. 2159 if (SC == VarDecl::Static) { 2160 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2161 diag::err_static_out_of_line) 2162 << CodeModificationHint::CreateRemoval( 2163 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2164 } else if (SC == VarDecl::None) 2165 SC = VarDecl::Static; 2166 } 2167 if (SC == VarDecl::Static) { 2168 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2169 if (RD->isLocalClass()) 2170 Diag(D.getIdentifierLoc(), 2171 diag::err_static_data_member_not_allowed_in_local_class) 2172 << Name << RD->getDeclName(); 2173 } 2174 } 2175 2176 // Match up the template parameter lists with the scope specifier, then 2177 // determine whether we have a template or a template specialization. 2178 bool isExplicitSpecialization = false; 2179 if (TemplateParameterList *TemplateParams 2180 = MatchTemplateParametersToScopeSpecifier( 2181 D.getDeclSpec().getSourceRange().getBegin(), 2182 D.getCXXScopeSpec(), 2183 (TemplateParameterList**)TemplateParamLists.get(), 2184 TemplateParamLists.size(), 2185 isExplicitSpecialization)) { 2186 if (TemplateParams->size() > 0) { 2187 // There is no such thing as a variable template. 2188 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2189 << II 2190 << SourceRange(TemplateParams->getTemplateLoc(), 2191 TemplateParams->getRAngleLoc()); 2192 return 0; 2193 } else { 2194 // There is an extraneous 'template<>' for this variable. Complain 2195 // about it, but allow the declaration of the variable. 2196 Diag(TemplateParams->getTemplateLoc(), 2197 diag::err_template_variable_noparams) 2198 << II 2199 << SourceRange(TemplateParams->getTemplateLoc(), 2200 TemplateParams->getRAngleLoc()); 2201 2202 isExplicitSpecialization = true; 2203 } 2204 } 2205 2206 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2207 II, R, DInfo, SC); 2208 2209 if (D.isInvalidType()) 2210 NewVD->setInvalidDecl(); 2211 2212 if (D.getDeclSpec().isThreadSpecified()) { 2213 if (NewVD->hasLocalStorage()) 2214 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2215 else if (!Context.Target.isTLSSupported()) 2216 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2217 else 2218 NewVD->setThreadSpecified(true); 2219 } 2220 2221 // Set the lexical context. If the declarator has a C++ scope specifier, the 2222 // lexical context will be different from the semantic context. 2223 NewVD->setLexicalDeclContext(CurContext); 2224 2225 // Handle attributes prior to checking for duplicates in MergeVarDecl 2226 ProcessDeclAttributes(S, NewVD, D); 2227 2228 // Handle GNU asm-label extension (encoded as an attribute). 2229 if (Expr *E = (Expr*) D.getAsmLabel()) { 2230 // The parser guarantees this is a string. 2231 StringLiteral *SE = cast<StringLiteral>(E); 2232 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2233 SE->getByteLength()))); 2234 } 2235 2236 // If name lookup finds a previous declaration that is not in the 2237 // same scope as the new declaration, this may still be an 2238 // acceptable redeclaration. 2239 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2240 !(NewVD->hasLinkage() && 2241 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2242 PrevDecl = 0; 2243 2244 // Merge the decl with the existing one if appropriate. 2245 if (PrevDecl) { 2246 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2247 // The user tried to define a non-static data member 2248 // out-of-line (C++ [dcl.meaning]p1). 2249 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2250 << D.getCXXScopeSpec().getRange(); 2251 PrevDecl = 0; 2252 NewVD->setInvalidDecl(); 2253 } 2254 } else if (D.getCXXScopeSpec().isSet()) { 2255 // No previous declaration in the qualifying scope. 2256 Diag(D.getIdentifierLoc(), diag::err_no_member) 2257 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2258 << D.getCXXScopeSpec().getRange(); 2259 NewVD->setInvalidDecl(); 2260 } 2261 2262 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2263 2264 // This is an explicit specialization of a static data member. Check it. 2265 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2266 CheckMemberSpecialization(NewVD, PrevDecl)) 2267 NewVD->setInvalidDecl(); 2268 2269 // attributes declared post-definition are currently ignored 2270 if (PrevDecl) { 2271 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2272 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2273 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2274 Diag(Def->getLocation(), diag::note_previous_definition); 2275 } 2276 } 2277 2278 // If this is a locally-scoped extern C variable, update the map of 2279 // such variables. 2280 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2281 !NewVD->isInvalidDecl()) 2282 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2283 2284 return NewVD; 2285} 2286 2287/// \brief Perform semantic checking on a newly-created variable 2288/// declaration. 2289/// 2290/// This routine performs all of the type-checking required for a 2291/// variable declaration once it has been built. It is used both to 2292/// check variables after they have been parsed and their declarators 2293/// have been translated into a declaration, and to check variables 2294/// that have been instantiated from a template. 2295/// 2296/// Sets NewVD->isInvalidDecl() if an error was encountered. 2297void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2298 bool &Redeclaration) { 2299 // If the decl is already known invalid, don't check it. 2300 if (NewVD->isInvalidDecl()) 2301 return; 2302 2303 QualType T = NewVD->getType(); 2304 2305 if (T->isObjCInterfaceType()) { 2306 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2307 return NewVD->setInvalidDecl(); 2308 } 2309 2310 // The variable can not have an abstract class type. 2311 if (RequireNonAbstractType(NewVD->getLocation(), T, 2312 diag::err_abstract_type_in_decl, 2313 AbstractVariableType)) 2314 return NewVD->setInvalidDecl(); 2315 2316 // Emit an error if an address space was applied to decl with local storage. 2317 // This includes arrays of objects with address space qualifiers, but not 2318 // automatic variables that point to other address spaces. 2319 // ISO/IEC TR 18037 S5.1.2 2320 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2321 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2322 return NewVD->setInvalidDecl(); 2323 } 2324 2325 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2326 && !NewVD->hasAttr<BlocksAttr>()) 2327 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2328 2329 bool isVM = T->isVariablyModifiedType(); 2330 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2331 NewVD->hasAttr<BlocksAttr>()) 2332 CurFunctionNeedsScopeChecking = true; 2333 2334 if ((isVM && NewVD->hasLinkage()) || 2335 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2336 bool SizeIsNegative; 2337 QualType FixedTy = 2338 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2339 2340 if (FixedTy.isNull() && T->isVariableArrayType()) { 2341 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2342 // FIXME: This won't give the correct result for 2343 // int a[10][n]; 2344 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2345 2346 if (NewVD->isFileVarDecl()) 2347 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2348 << SizeRange; 2349 else if (NewVD->getStorageClass() == VarDecl::Static) 2350 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2351 << SizeRange; 2352 else 2353 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2354 << SizeRange; 2355 return NewVD->setInvalidDecl(); 2356 } 2357 2358 if (FixedTy.isNull()) { 2359 if (NewVD->isFileVarDecl()) 2360 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2361 else 2362 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2363 return NewVD->setInvalidDecl(); 2364 } 2365 2366 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2367 NewVD->setType(FixedTy); 2368 } 2369 2370 if (!PrevDecl && NewVD->isExternC()) { 2371 // Since we did not find anything by this name and we're declaring 2372 // an extern "C" variable, look for a non-visible extern "C" 2373 // declaration with the same name. 2374 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2375 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2376 if (Pos != LocallyScopedExternalDecls.end()) 2377 PrevDecl = Pos->second; 2378 } 2379 2380 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2381 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2382 << T; 2383 return NewVD->setInvalidDecl(); 2384 } 2385 2386 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2387 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2388 return NewVD->setInvalidDecl(); 2389 } 2390 2391 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2392 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2393 return NewVD->setInvalidDecl(); 2394 } 2395 2396 if (PrevDecl) { 2397 Redeclaration = true; 2398 MergeVarDecl(NewVD, PrevDecl); 2399 } 2400} 2401 2402static bool isUsingDecl(Decl *D) { 2403 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2404} 2405 2406/// \brief Data used with FindOverriddenMethod 2407struct FindOverriddenMethodData { 2408 Sema *S; 2409 CXXMethodDecl *Method; 2410}; 2411 2412/// \brief Member lookup function that determines whether a given C++ 2413/// method overrides a method in a base class, to be used with 2414/// CXXRecordDecl::lookupInBases(). 2415static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2416 CXXBasePath &Path, 2417 void *UserData) { 2418 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2419 2420 FindOverriddenMethodData *Data 2421 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2422 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2423 Path.Decls.first != Path.Decls.second; 2424 ++Path.Decls.first) { 2425 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2426 OverloadedFunctionDecl::function_iterator MatchedDecl; 2427 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2428 return true; 2429 } 2430 } 2431 2432 return false; 2433} 2434 2435NamedDecl* 2436Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2437 QualType R, DeclaratorInfo *DInfo, 2438 NamedDecl* PrevDecl, 2439 MultiTemplateParamsArg TemplateParamLists, 2440 bool IsFunctionDefinition, bool &Redeclaration) { 2441 assert(R.getTypePtr()->isFunctionType()); 2442 2443 DeclarationName Name = GetNameForDeclarator(D); 2444 FunctionDecl::StorageClass SC = FunctionDecl::None; 2445 switch (D.getDeclSpec().getStorageClassSpec()) { 2446 default: assert(0 && "Unknown storage class!"); 2447 case DeclSpec::SCS_auto: 2448 case DeclSpec::SCS_register: 2449 case DeclSpec::SCS_mutable: 2450 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2451 diag::err_typecheck_sclass_func); 2452 D.setInvalidType(); 2453 break; 2454 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2455 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2456 case DeclSpec::SCS_static: { 2457 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2458 // C99 6.7.1p5: 2459 // The declaration of an identifier for a function that has 2460 // block scope shall have no explicit storage-class specifier 2461 // other than extern 2462 // See also (C++ [dcl.stc]p4). 2463 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2464 diag::err_static_block_func); 2465 SC = FunctionDecl::None; 2466 } else 2467 SC = FunctionDecl::Static; 2468 break; 2469 } 2470 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2471 } 2472 2473 if (D.getDeclSpec().isThreadSpecified()) 2474 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2475 2476 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2477 bool isInline = D.getDeclSpec().isInlineSpecified(); 2478 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2479 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2480 2481 // Check that the return type is not an abstract class type. 2482 // For record types, this is done by the AbstractClassUsageDiagnoser once 2483 // the class has been completely parsed. 2484 if (!DC->isRecord() && 2485 RequireNonAbstractType(D.getIdentifierLoc(), 2486 R->getAs<FunctionType>()->getResultType(), 2487 diag::err_abstract_type_in_decl, 2488 AbstractReturnType)) 2489 D.setInvalidType(); 2490 2491 // Do not allow returning a objc interface by-value. 2492 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2493 Diag(D.getIdentifierLoc(), 2494 diag::err_object_cannot_be_passed_returned_by_value) << 0 2495 << R->getAs<FunctionType>()->getResultType(); 2496 D.setInvalidType(); 2497 } 2498 2499 bool isVirtualOkay = false; 2500 FunctionDecl *NewFD; 2501 2502 if (isFriend) { 2503 // DC is the namespace in which the function is being declared. 2504 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2505 "friend function being created in a non-namespace context"); 2506 2507 // C++ [class.friend]p5 2508 // A function can be defined in a friend declaration of a 2509 // class . . . . Such a function is implicitly inline. 2510 isInline |= IsFunctionDefinition; 2511 } 2512 2513 if (D.getKind() == Declarator::DK_Constructor) { 2514 // This is a C++ constructor declaration. 2515 assert(DC->isRecord() && 2516 "Constructors can only be declared in a member context"); 2517 2518 R = CheckConstructorDeclarator(D, R, SC); 2519 2520 // Create the new declaration 2521 NewFD = CXXConstructorDecl::Create(Context, 2522 cast<CXXRecordDecl>(DC), 2523 D.getIdentifierLoc(), Name, R, DInfo, 2524 isExplicit, isInline, 2525 /*isImplicitlyDeclared=*/false); 2526 } else if (D.getKind() == Declarator::DK_Destructor) { 2527 // This is a C++ destructor declaration. 2528 if (DC->isRecord()) { 2529 R = CheckDestructorDeclarator(D, SC); 2530 2531 NewFD = CXXDestructorDecl::Create(Context, 2532 cast<CXXRecordDecl>(DC), 2533 D.getIdentifierLoc(), Name, R, 2534 isInline, 2535 /*isImplicitlyDeclared=*/false); 2536 2537 isVirtualOkay = true; 2538 } else { 2539 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2540 2541 // Create a FunctionDecl to satisfy the function definition parsing 2542 // code path. 2543 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2544 Name, R, DInfo, SC, isInline, 2545 /*hasPrototype=*/true); 2546 D.setInvalidType(); 2547 } 2548 } else if (D.getKind() == Declarator::DK_Conversion) { 2549 if (!DC->isRecord()) { 2550 Diag(D.getIdentifierLoc(), 2551 diag::err_conv_function_not_member); 2552 return 0; 2553 } 2554 2555 CheckConversionDeclarator(D, R, SC); 2556 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2557 D.getIdentifierLoc(), Name, R, DInfo, 2558 isInline, isExplicit); 2559 2560 isVirtualOkay = true; 2561 } else if (DC->isRecord()) { 2562 // If the of the function is the same as the name of the record, then this 2563 // must be an invalid constructor that has a return type. 2564 // (The parser checks for a return type and makes the declarator a 2565 // constructor if it has no return type). 2566 // must have an invalid constructor that has a return type 2567 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2568 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2569 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2570 << SourceRange(D.getIdentifierLoc()); 2571 return 0; 2572 } 2573 2574 // This is a C++ method declaration. 2575 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2576 D.getIdentifierLoc(), Name, R, DInfo, 2577 (SC == FunctionDecl::Static), isInline); 2578 2579 isVirtualOkay = (SC != FunctionDecl::Static); 2580 } else { 2581 // Determine whether the function was written with a 2582 // prototype. This true when: 2583 // - we're in C++ (where every function has a prototype), 2584 // - there is a prototype in the declarator, or 2585 // - the type R of the function is some kind of typedef or other reference 2586 // to a type name (which eventually refers to a function type). 2587 bool HasPrototype = 2588 getLangOptions().CPlusPlus || 2589 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2590 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2591 2592 NewFD = FunctionDecl::Create(Context, DC, 2593 D.getIdentifierLoc(), 2594 Name, R, DInfo, SC, isInline, HasPrototype); 2595 } 2596 2597 if (D.isInvalidType()) 2598 NewFD->setInvalidDecl(); 2599 2600 // Set the lexical context. If the declarator has a C++ 2601 // scope specifier, or is the object of a friend declaration, the 2602 // lexical context will be different from the semantic context. 2603 NewFD->setLexicalDeclContext(CurContext); 2604 2605 // Match up the template parameter lists with the scope specifier, then 2606 // determine whether we have a template or a template specialization. 2607 FunctionTemplateDecl *FunctionTemplate = 0; 2608 bool isExplicitSpecialization = false; 2609 bool isFunctionTemplateSpecialization = false; 2610 if (TemplateParameterList *TemplateParams 2611 = MatchTemplateParametersToScopeSpecifier( 2612 D.getDeclSpec().getSourceRange().getBegin(), 2613 D.getCXXScopeSpec(), 2614 (TemplateParameterList**)TemplateParamLists.get(), 2615 TemplateParamLists.size(), 2616 isExplicitSpecialization)) { 2617 if (TemplateParams->size() > 0) { 2618 // This is a function template 2619 2620 // Check that we can declare a template here. 2621 if (CheckTemplateDeclScope(S, TemplateParams)) 2622 return 0; 2623 2624 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2625 NewFD->getLocation(), 2626 Name, TemplateParams, 2627 NewFD); 2628 FunctionTemplate->setLexicalDeclContext(CurContext); 2629 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2630 } else { 2631 // This is a function template specialization. 2632 isFunctionTemplateSpecialization = true; 2633 } 2634 2635 // FIXME: Free this memory properly. 2636 TemplateParamLists.release(); 2637 } 2638 2639 // C++ [dcl.fct.spec]p5: 2640 // The virtual specifier shall only be used in declarations of 2641 // nonstatic class member functions that appear within a 2642 // member-specification of a class declaration; see 10.3. 2643 // 2644 if (isVirtual && !NewFD->isInvalidDecl()) { 2645 if (!isVirtualOkay) { 2646 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2647 diag::err_virtual_non_function); 2648 } else if (!CurContext->isRecord()) { 2649 // 'virtual' was specified outside of the class. 2650 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2651 << CodeModificationHint::CreateRemoval( 2652 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2653 } else { 2654 // Okay: Add virtual to the method. 2655 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2656 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2657 CurClass->setAggregate(false); 2658 CurClass->setPOD(false); 2659 CurClass->setEmpty(false); 2660 CurClass->setPolymorphic(true); 2661 CurClass->setHasTrivialConstructor(false); 2662 CurClass->setHasTrivialCopyConstructor(false); 2663 CurClass->setHasTrivialCopyAssignment(false); 2664 } 2665 } 2666 2667 if (isFriend) { 2668 if (FunctionTemplate) { 2669 FunctionTemplate->setObjectOfFriendDecl( 2670 /* PreviouslyDeclared= */ PrevDecl != NULL); 2671 FunctionTemplate->setAccess(AS_public); 2672 } 2673 else 2674 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2675 2676 NewFD->setAccess(AS_public); 2677 } 2678 2679 2680 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2681 // Look for virtual methods in base classes that this method might override. 2682 CXXBasePaths Paths; 2683 FindOverriddenMethodData Data; 2684 Data.Method = NewMD; 2685 Data.S = this; 2686 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2687 Paths)) { 2688 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2689 E = Paths.found_decls_end(); I != E; ++I) { 2690 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2691 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2692 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2693 NewMD->addOverriddenMethod(OldMD); 2694 } 2695 } 2696 } 2697 } 2698 2699 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2700 !CurContext->isRecord()) { 2701 // C++ [class.static]p1: 2702 // A data or function member of a class may be declared static 2703 // in a class definition, in which case it is a static member of 2704 // the class. 2705 2706 // Complain about the 'static' specifier if it's on an out-of-line 2707 // member function definition. 2708 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2709 diag::err_static_out_of_line) 2710 << CodeModificationHint::CreateRemoval( 2711 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2712 } 2713 2714 // Handle GNU asm-label extension (encoded as an attribute). 2715 if (Expr *E = (Expr*) D.getAsmLabel()) { 2716 // The parser guarantees this is a string. 2717 StringLiteral *SE = cast<StringLiteral>(E); 2718 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2719 SE->getByteLength()))); 2720 } 2721 2722 // Copy the parameter declarations from the declarator D to the function 2723 // declaration NewFD, if they are available. First scavenge them into Params. 2724 llvm::SmallVector<ParmVarDecl*, 16> Params; 2725 if (D.getNumTypeObjects() > 0) { 2726 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2727 2728 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2729 // function that takes no arguments, not a function that takes a 2730 // single void argument. 2731 // We let through "const void" here because Sema::GetTypeForDeclarator 2732 // already checks for that case. 2733 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2734 FTI.ArgInfo[0].Param && 2735 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2736 // Empty arg list, don't push any params. 2737 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2738 2739 // In C++, the empty parameter-type-list must be spelled "void"; a 2740 // typedef of void is not permitted. 2741 if (getLangOptions().CPlusPlus && 2742 Param->getType().getUnqualifiedType() != Context.VoidTy) 2743 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2744 // FIXME: Leaks decl? 2745 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2746 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2747 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2748 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2749 Param->setDeclContext(NewFD); 2750 Params.push_back(Param); 2751 } 2752 } 2753 2754 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2755 // When we're declaring a function with a typedef, typeof, etc as in the 2756 // following example, we'll need to synthesize (unnamed) 2757 // parameters for use in the declaration. 2758 // 2759 // @code 2760 // typedef void fn(int); 2761 // fn f; 2762 // @endcode 2763 2764 // Synthesize a parameter for each argument type. 2765 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2766 AE = FT->arg_type_end(); AI != AE; ++AI) { 2767 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2768 SourceLocation(), 0, 2769 *AI, /*DInfo=*/0, 2770 VarDecl::None, 0); 2771 Param->setImplicit(); 2772 Params.push_back(Param); 2773 } 2774 } else { 2775 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2776 "Should not need args for typedef of non-prototype fn"); 2777 } 2778 // Finally, we know we have the right number of parameters, install them. 2779 NewFD->setParams(Context, Params.data(), Params.size()); 2780 2781 // If name lookup finds a previous declaration that is not in the 2782 // same scope as the new declaration, this may still be an 2783 // acceptable redeclaration. 2784 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2785 !(NewFD->hasLinkage() && 2786 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2787 PrevDecl = 0; 2788 2789 // If the declarator is a template-id, translate the parser's template 2790 // argument list into our AST format. 2791 bool HasExplicitTemplateArgs = false; 2792 llvm::SmallVector<TemplateArgument, 16> TemplateArgs; 2793 SourceLocation LAngleLoc, RAngleLoc; 2794 if (D.getKind() == Declarator::DK_TemplateId) { 2795 TemplateIdAnnotation *TemplateId = D.getTemplateId(); 2796 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2797 TemplateId->getTemplateArgs(), 2798 TemplateId->getTemplateArgIsType(), 2799 TemplateId->NumArgs); 2800 translateTemplateArguments(TemplateArgsPtr, 2801 TemplateId->getTemplateArgLocations(), 2802 TemplateArgs); 2803 TemplateArgsPtr.release(); 2804 2805 HasExplicitTemplateArgs = true; 2806 LAngleLoc = TemplateId->LAngleLoc; 2807 RAngleLoc = TemplateId->RAngleLoc; 2808 2809 if (FunctionTemplate) { 2810 // FIXME: Diagnose function template with explicit template 2811 // arguments. 2812 HasExplicitTemplateArgs = false; 2813 } else if (!isFunctionTemplateSpecialization && 2814 !D.getDeclSpec().isFriendSpecified()) { 2815 // We have encountered something that the user meant to be a 2816 // specialization (because it has explicitly-specified template 2817 // arguments) but that was not introduced with a "template<>" (or had 2818 // too few of them). 2819 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2820 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2821 << CodeModificationHint::CreateInsertion( 2822 D.getDeclSpec().getSourceRange().getBegin(), 2823 "template<> "); 2824 isFunctionTemplateSpecialization = true; 2825 } 2826 } 2827 2828 if (isFunctionTemplateSpecialization) { 2829 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2830 LAngleLoc, TemplateArgs.data(), 2831 TemplateArgs.size(), RAngleLoc, 2832 PrevDecl)) 2833 NewFD->setInvalidDecl(); 2834 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2835 CheckMemberSpecialization(NewFD, PrevDecl)) 2836 NewFD->setInvalidDecl(); 2837 2838 // Perform semantic checking on the function declaration. 2839 bool OverloadableAttrRequired = false; // FIXME: HACK! 2840 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2841 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2842 2843 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2844 // An out-of-line member function declaration must also be a 2845 // definition (C++ [dcl.meaning]p1). 2846 // Note that this is not the case for explicit specializations of 2847 // function templates or member functions of class templates, per 2848 // C++ [temp.expl.spec]p2. 2849 if (!IsFunctionDefinition && !isFriend && 2850 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2851 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2852 << D.getCXXScopeSpec().getRange(); 2853 NewFD->setInvalidDecl(); 2854 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2855 // The user tried to provide an out-of-line definition for a 2856 // function that is a member of a class or namespace, but there 2857 // was no such member function declared (C++ [class.mfct]p2, 2858 // C++ [namespace.memdef]p2). For example: 2859 // 2860 // class X { 2861 // void f() const; 2862 // }; 2863 // 2864 // void X::f() { } // ill-formed 2865 // 2866 // Complain about this problem, and attempt to suggest close 2867 // matches (e.g., those that differ only in cv-qualifiers and 2868 // whether the parameter types are references). 2869 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2870 << Name << DC << D.getCXXScopeSpec().getRange(); 2871 NewFD->setInvalidDecl(); 2872 2873 LookupResult Prev; 2874 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2875 assert(!Prev.isAmbiguous() && 2876 "Cannot have an ambiguity in previous-declaration lookup"); 2877 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2878 Func != FuncEnd; ++Func) { 2879 if (isa<FunctionDecl>(*Func) && 2880 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2881 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2882 } 2883 2884 PrevDecl = 0; 2885 } 2886 } 2887 2888 // Handle attributes. We need to have merged decls when handling attributes 2889 // (for example to check for conflicts, etc). 2890 // FIXME: This needs to happen before we merge declarations. Then, 2891 // let attribute merging cope with attribute conflicts. 2892 ProcessDeclAttributes(S, NewFD, D); 2893 2894 // attributes declared post-definition are currently ignored 2895 if (Redeclaration && PrevDecl) { 2896 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2897 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2898 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2899 Diag(Def->getLocation(), diag::note_previous_definition); 2900 } 2901 } 2902 2903 AddKnownFunctionAttributes(NewFD); 2904 2905 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2906 // If a function name is overloadable in C, then every function 2907 // with that name must be marked "overloadable". 2908 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2909 << Redeclaration << NewFD; 2910 if (PrevDecl) 2911 Diag(PrevDecl->getLocation(), 2912 diag::note_attribute_overloadable_prev_overload); 2913 NewFD->addAttr(::new (Context) OverloadableAttr()); 2914 } 2915 2916 // If this is a locally-scoped extern C function, update the 2917 // map of such names. 2918 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2919 && !NewFD->isInvalidDecl()) 2920 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2921 2922 // Set this FunctionDecl's range up to the right paren. 2923 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2924 2925 if (FunctionTemplate && NewFD->isInvalidDecl()) 2926 FunctionTemplate->setInvalidDecl(); 2927 2928 if (FunctionTemplate) 2929 return FunctionTemplate; 2930 2931 return NewFD; 2932} 2933 2934/// \brief Perform semantic checking of a new function declaration. 2935/// 2936/// Performs semantic analysis of the new function declaration 2937/// NewFD. This routine performs all semantic checking that does not 2938/// require the actual declarator involved in the declaration, and is 2939/// used both for the declaration of functions as they are parsed 2940/// (called via ActOnDeclarator) and for the declaration of functions 2941/// that have been instantiated via C++ template instantiation (called 2942/// via InstantiateDecl). 2943/// 2944/// \param IsExplicitSpecialiation whether this new function declaration is 2945/// an explicit specialization of the previous declaration. 2946/// 2947/// This sets NewFD->isInvalidDecl() to true if there was an error. 2948void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2949 bool IsExplicitSpecialization, 2950 bool &Redeclaration, 2951 bool &OverloadableAttrRequired) { 2952 // If NewFD is already known erroneous, don't do any of this checking. 2953 if (NewFD->isInvalidDecl()) 2954 return; 2955 2956 if (NewFD->getResultType()->isVariablyModifiedType()) { 2957 // Functions returning a variably modified type violate C99 6.7.5.2p2 2958 // because all functions have linkage. 2959 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2960 return NewFD->setInvalidDecl(); 2961 } 2962 2963 if (NewFD->isMain()) 2964 CheckMain(NewFD); 2965 2966 // Check for a previous declaration of this name. 2967 if (!PrevDecl && NewFD->isExternC()) { 2968 // Since we did not find anything by this name and we're declaring 2969 // an extern "C" function, look for a non-visible extern "C" 2970 // declaration with the same name. 2971 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2972 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2973 if (Pos != LocallyScopedExternalDecls.end()) 2974 PrevDecl = Pos->second; 2975 } 2976 2977 // Merge or overload the declaration with an existing declaration of 2978 // the same name, if appropriate. 2979 if (PrevDecl) { 2980 // Determine whether NewFD is an overload of PrevDecl or 2981 // a declaration that requires merging. If it's an overload, 2982 // there's no more work to do here; we'll just add the new 2983 // function to the scope. 2984 OverloadedFunctionDecl::function_iterator MatchedDecl; 2985 2986 if (!getLangOptions().CPlusPlus && 2987 AllowOverloadingOfFunction(PrevDecl, Context)) { 2988 OverloadableAttrRequired = true; 2989 2990 // Functions marked "overloadable" must have a prototype (that 2991 // we can't get through declaration merging). 2992 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 2993 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2994 << NewFD; 2995 Redeclaration = true; 2996 2997 // Turn this into a variadic function with no parameters. 2998 QualType R = Context.getFunctionType( 2999 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3000 0, 0, true, 0); 3001 NewFD->setType(R); 3002 return NewFD->setInvalidDecl(); 3003 } 3004 } 3005 3006 if (PrevDecl && 3007 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3008 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3009 Redeclaration = true; 3010 Decl *OldDecl = PrevDecl; 3011 3012 // If PrevDecl was an overloaded function, extract the 3013 // FunctionDecl that matched. 3014 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3015 OldDecl = *MatchedDecl; 3016 3017 // NewFD and OldDecl represent declarations that need to be 3018 // merged. 3019 if (MergeFunctionDecl(NewFD, OldDecl)) 3020 return NewFD->setInvalidDecl(); 3021 3022 if (FunctionTemplateDecl *OldTemplateDecl 3023 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3024 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3025 FunctionTemplateDecl *NewTemplateDecl 3026 = NewFD->getDescribedFunctionTemplate(); 3027 assert(NewTemplateDecl && "Template/non-template mismatch"); 3028 if (CXXMethodDecl *Method 3029 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3030 Method->setAccess(OldTemplateDecl->getAccess()); 3031 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3032 } 3033 3034 // If this is an explicit specialization of a member that is a function 3035 // template, mark it as a member specialization. 3036 if (IsExplicitSpecialization && 3037 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3038 NewTemplateDecl->setMemberSpecialization(); 3039 assert(OldTemplateDecl->isMemberSpecialization()); 3040 } 3041 } else { 3042 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3043 NewFD->setAccess(OldDecl->getAccess()); 3044 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3045 } 3046 } 3047 } 3048 3049 // Semantic checking for this function declaration (in isolation). 3050 if (getLangOptions().CPlusPlus) { 3051 // C++-specific checks. 3052 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3053 CheckConstructor(Constructor); 3054 } else if (isa<CXXDestructorDecl>(NewFD)) { 3055 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3056 QualType ClassType = Context.getTypeDeclType(Record); 3057 if (!ClassType->isDependentType()) { 3058 DeclarationName Name 3059 = Context.DeclarationNames.getCXXDestructorName( 3060 Context.getCanonicalType(ClassType)); 3061 if (NewFD->getDeclName() != Name) { 3062 Diag(NewFD->getLocation(), diag::err_destructor_name); 3063 return NewFD->setInvalidDecl(); 3064 } 3065 } 3066 Record->setUserDeclaredDestructor(true); 3067 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3068 // user-defined destructor. 3069 Record->setPOD(false); 3070 3071 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3072 // declared destructor. 3073 // FIXME: C++0x: don't do this for "= default" destructors 3074 Record->setHasTrivialDestructor(false); 3075 } else if (CXXConversionDecl *Conversion 3076 = dyn_cast<CXXConversionDecl>(NewFD)) 3077 ActOnConversionDeclarator(Conversion); 3078 3079 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3080 if (NewFD->isOverloadedOperator() && 3081 CheckOverloadedOperatorDeclaration(NewFD)) 3082 return NewFD->setInvalidDecl(); 3083 3084 // In C++, check default arguments now that we have merged decls. Unless 3085 // the lexical context is the class, because in this case this is done 3086 // during delayed parsing anyway. 3087 if (!CurContext->isRecord()) 3088 CheckCXXDefaultArguments(NewFD); 3089 } 3090} 3091 3092void Sema::CheckMain(FunctionDecl* FD) { 3093 // C++ [basic.start.main]p3: A program that declares main to be inline 3094 // or static is ill-formed. 3095 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3096 // shall not appear in a declaration of main. 3097 // static main is not an error under C99, but we should warn about it. 3098 bool isInline = FD->isInline(); 3099 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3100 if (isInline || isStatic) { 3101 unsigned diagID = diag::warn_unusual_main_decl; 3102 if (isInline || getLangOptions().CPlusPlus) 3103 diagID = diag::err_unusual_main_decl; 3104 3105 int which = isStatic + (isInline << 1) - 1; 3106 Diag(FD->getLocation(), diagID) << which; 3107 } 3108 3109 QualType T = FD->getType(); 3110 assert(T->isFunctionType() && "function decl is not of function type"); 3111 const FunctionType* FT = T->getAs<FunctionType>(); 3112 3113 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3114 // TODO: add a replacement fixit to turn the return type into 'int'. 3115 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3116 FD->setInvalidDecl(true); 3117 } 3118 3119 // Treat protoless main() as nullary. 3120 if (isa<FunctionNoProtoType>(FT)) return; 3121 3122 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3123 unsigned nparams = FTP->getNumArgs(); 3124 assert(FD->getNumParams() == nparams); 3125 3126 if (nparams > 3) { 3127 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3128 FD->setInvalidDecl(true); 3129 nparams = 3; 3130 } 3131 3132 // FIXME: a lot of the following diagnostics would be improved 3133 // if we had some location information about types. 3134 3135 QualType CharPP = 3136 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3137 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3138 3139 for (unsigned i = 0; i < nparams; ++i) { 3140 QualType AT = FTP->getArgType(i); 3141 3142 bool mismatch = true; 3143 3144 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3145 mismatch = false; 3146 else if (Expected[i] == CharPP) { 3147 // As an extension, the following forms are okay: 3148 // char const ** 3149 // char const * const * 3150 // char * const * 3151 3152 QualifierCollector qs; 3153 const PointerType* PT; 3154 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3155 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3156 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3157 qs.removeConst(); 3158 mismatch = !qs.empty(); 3159 } 3160 } 3161 3162 if (mismatch) { 3163 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3164 // TODO: suggest replacing given type with expected type 3165 FD->setInvalidDecl(true); 3166 } 3167 } 3168 3169 if (nparams == 1 && !FD->isInvalidDecl()) { 3170 Diag(FD->getLocation(), diag::warn_main_one_arg); 3171 } 3172} 3173 3174bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3175 // FIXME: Need strict checking. In C89, we need to check for 3176 // any assignment, increment, decrement, function-calls, or 3177 // commas outside of a sizeof. In C99, it's the same list, 3178 // except that the aforementioned are allowed in unevaluated 3179 // expressions. Everything else falls under the 3180 // "may accept other forms of constant expressions" exception. 3181 // (We never end up here for C++, so the constant expression 3182 // rules there don't matter.) 3183 if (Init->isConstantInitializer(Context)) 3184 return false; 3185 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3186 << Init->getSourceRange(); 3187 return true; 3188} 3189 3190void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3191 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3192} 3193 3194/// AddInitializerToDecl - Adds the initializer Init to the 3195/// declaration dcl. If DirectInit is true, this is C++ direct 3196/// initialization rather than copy initialization. 3197void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3198 Decl *RealDecl = dcl.getAs<Decl>(); 3199 // If there is no declaration, there was an error parsing it. Just ignore 3200 // the initializer. 3201 if (RealDecl == 0) 3202 return; 3203 3204 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3205 // With declarators parsed the way they are, the parser cannot 3206 // distinguish between a normal initializer and a pure-specifier. 3207 // Thus this grotesque test. 3208 IntegerLiteral *IL; 3209 Expr *Init = static_cast<Expr *>(init.get()); 3210 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3211 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3212 if (Method->isVirtualAsWritten()) { 3213 Method->setPure(); 3214 3215 // A class is abstract if at least one function is pure virtual. 3216 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3217 } else if (!Method->isInvalidDecl()) { 3218 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3219 << Method->getDeclName() << Init->getSourceRange(); 3220 Method->setInvalidDecl(); 3221 } 3222 } else { 3223 Diag(Method->getLocation(), diag::err_member_function_initialization) 3224 << Method->getDeclName() << Init->getSourceRange(); 3225 Method->setInvalidDecl(); 3226 } 3227 return; 3228 } 3229 3230 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3231 if (!VDecl) { 3232 if (getLangOptions().CPlusPlus && 3233 RealDecl->getLexicalDeclContext()->isRecord() && 3234 isa<NamedDecl>(RealDecl)) 3235 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3236 << cast<NamedDecl>(RealDecl)->getDeclName(); 3237 else 3238 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3239 RealDecl->setInvalidDecl(); 3240 return; 3241 } 3242 3243 if (!VDecl->getType()->isArrayType() && 3244 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3245 diag::err_typecheck_decl_incomplete_type)) { 3246 RealDecl->setInvalidDecl(); 3247 return; 3248 } 3249 3250 const VarDecl *Def = 0; 3251 if (VDecl->getDefinition(Def)) { 3252 Diag(VDecl->getLocation(), diag::err_redefinition) 3253 << VDecl->getDeclName(); 3254 Diag(Def->getLocation(), diag::note_previous_definition); 3255 VDecl->setInvalidDecl(); 3256 return; 3257 } 3258 3259 // Take ownership of the expression, now that we're sure we have somewhere 3260 // to put it. 3261 Expr *Init = init.takeAs<Expr>(); 3262 assert(Init && "missing initializer"); 3263 3264 // Get the decls type and save a reference for later, since 3265 // CheckInitializerTypes may change it. 3266 QualType DclT = VDecl->getType(), SavT = DclT; 3267 if (VDecl->isBlockVarDecl()) { 3268 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3269 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3270 VDecl->setInvalidDecl(); 3271 } else if (!VDecl->isInvalidDecl()) { 3272 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3273 VDecl->getDeclName(), DirectInit)) 3274 VDecl->setInvalidDecl(); 3275 3276 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3277 // Don't check invalid declarations to avoid emitting useless diagnostics. 3278 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3279 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3280 CheckForConstantInitializer(Init, DclT); 3281 } 3282 } 3283 } else if (VDecl->isStaticDataMember() && 3284 VDecl->getLexicalDeclContext()->isRecord()) { 3285 // This is an in-class initialization for a static data member, e.g., 3286 // 3287 // struct S { 3288 // static const int value = 17; 3289 // }; 3290 3291 // Attach the initializer 3292 VDecl->setInit(Context, Init); 3293 3294 // C++ [class.mem]p4: 3295 // A member-declarator can contain a constant-initializer only 3296 // if it declares a static member (9.4) of const integral or 3297 // const enumeration type, see 9.4.2. 3298 QualType T = VDecl->getType(); 3299 if (!T->isDependentType() && 3300 (!Context.getCanonicalType(T).isConstQualified() || 3301 !T->isIntegralType())) { 3302 Diag(VDecl->getLocation(), diag::err_member_initialization) 3303 << VDecl->getDeclName() << Init->getSourceRange(); 3304 VDecl->setInvalidDecl(); 3305 } else { 3306 // C++ [class.static.data]p4: 3307 // If a static data member is of const integral or const 3308 // enumeration type, its declaration in the class definition 3309 // can specify a constant-initializer which shall be an 3310 // integral constant expression (5.19). 3311 if (!Init->isTypeDependent() && 3312 !Init->getType()->isIntegralType()) { 3313 // We have a non-dependent, non-integral or enumeration type. 3314 Diag(Init->getSourceRange().getBegin(), 3315 diag::err_in_class_initializer_non_integral_type) 3316 << Init->getType() << Init->getSourceRange(); 3317 VDecl->setInvalidDecl(); 3318 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3319 // Check whether the expression is a constant expression. 3320 llvm::APSInt Value; 3321 SourceLocation Loc; 3322 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3323 Diag(Loc, diag::err_in_class_initializer_non_constant) 3324 << Init->getSourceRange(); 3325 VDecl->setInvalidDecl(); 3326 } else if (!VDecl->getType()->isDependentType()) 3327 ImpCastExprToType(Init, VDecl->getType()); 3328 } 3329 } 3330 } else if (VDecl->isFileVarDecl()) { 3331 if (VDecl->getStorageClass() == VarDecl::Extern) 3332 Diag(VDecl->getLocation(), diag::warn_extern_init); 3333 if (!VDecl->isInvalidDecl()) 3334 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3335 VDecl->getDeclName(), DirectInit)) 3336 VDecl->setInvalidDecl(); 3337 3338 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3339 // Don't check invalid declarations to avoid emitting useless diagnostics. 3340 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3341 // C99 6.7.8p4. All file scoped initializers need to be constant. 3342 CheckForConstantInitializer(Init, DclT); 3343 } 3344 } 3345 // If the type changed, it means we had an incomplete type that was 3346 // completed by the initializer. For example: 3347 // int ary[] = { 1, 3, 5 }; 3348 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3349 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3350 VDecl->setType(DclT); 3351 Init->setType(DclT); 3352 } 3353 3354 Init = MaybeCreateCXXExprWithTemporaries(Init, 3355 /*ShouldDestroyTemporaries=*/true); 3356 // Attach the initializer to the decl. 3357 VDecl->setInit(Context, Init); 3358 3359 // If the previous declaration of VDecl was a tentative definition, 3360 // remove it from the set of tentative definitions. 3361 if (VDecl->getPreviousDeclaration() && 3362 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3363 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3364 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3365 } 3366 3367 return; 3368} 3369 3370void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3371 bool TypeContainsUndeducedAuto) { 3372 Decl *RealDecl = dcl.getAs<Decl>(); 3373 3374 // If there is no declaration, there was an error parsing it. Just ignore it. 3375 if (RealDecl == 0) 3376 return; 3377 3378 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3379 QualType Type = Var->getType(); 3380 3381 // Record tentative definitions. 3382 if (Var->isTentativeDefinition(Context)) { 3383 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3384 InsertPair = 3385 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3386 3387 // Keep the latest definition in the map. If we see 'int i; int i;' we 3388 // want the second one in the map. 3389 InsertPair.first->second = Var; 3390 3391 // However, for the list, we don't care about the order, just make sure 3392 // that there are no dupes for a given declaration name. 3393 if (InsertPair.second) 3394 TentativeDefinitionList.push_back(Var->getDeclName()); 3395 } 3396 3397 // C++ [dcl.init.ref]p3: 3398 // The initializer can be omitted for a reference only in a 3399 // parameter declaration (8.3.5), in the declaration of a 3400 // function return type, in the declaration of a class member 3401 // within its class declaration (9.2), and where the extern 3402 // specifier is explicitly used. 3403 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3404 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3405 << Var->getDeclName() 3406 << SourceRange(Var->getLocation(), Var->getLocation()); 3407 Var->setInvalidDecl(); 3408 return; 3409 } 3410 3411 // C++0x [dcl.spec.auto]p3 3412 if (TypeContainsUndeducedAuto) { 3413 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3414 << Var->getDeclName() << Type; 3415 Var->setInvalidDecl(); 3416 return; 3417 } 3418 3419 // C++ [temp.expl.spec]p15: 3420 // An explicit specialization of a static data member of a template is a 3421 // definition if the declaration includes an initializer; otherwise, it 3422 // is a declaration. 3423 if (Var->isStaticDataMember() && 3424 Var->getInstantiatedFromStaticDataMember() && 3425 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3426 return; 3427 3428 // C++ [dcl.init]p9: 3429 // If no initializer is specified for an object, and the object 3430 // is of (possibly cv-qualified) non-POD class type (or array 3431 // thereof), the object shall be default-initialized; if the 3432 // object is of const-qualified type, the underlying class type 3433 // shall have a user-declared default constructor. 3434 // 3435 // FIXME: Diagnose the "user-declared default constructor" bit. 3436 if (getLangOptions().CPlusPlus) { 3437 QualType InitType = Type; 3438 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3439 InitType = Array->getElementType(); 3440 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3441 InitType->isRecordType() && !InitType->isDependentType()) { 3442 if (!RequireCompleteType(Var->getLocation(), InitType, 3443 diag::err_invalid_incomplete_type_use)) { 3444 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3445 3446 CXXConstructorDecl *Constructor 3447 = PerformInitializationByConstructor(InitType, 3448 MultiExprArg(*this, 0, 0), 3449 Var->getLocation(), 3450 SourceRange(Var->getLocation(), 3451 Var->getLocation()), 3452 Var->getDeclName(), 3453 IK_Default, 3454 ConstructorArgs); 3455 3456 // FIXME: Location info for the variable initialization? 3457 if (!Constructor) 3458 Var->setInvalidDecl(); 3459 else { 3460 // FIXME: Cope with initialization of arrays 3461 if (!Constructor->isTrivial() && 3462 InitializeVarWithConstructor(Var, Constructor, InitType, 3463 move_arg(ConstructorArgs))) 3464 Var->setInvalidDecl(); 3465 3466 FinalizeVarWithDestructor(Var, InitType); 3467 } 3468 } else { 3469 Var->setInvalidDecl(); 3470 } 3471 } 3472 } 3473 3474#if 0 3475 // FIXME: Temporarily disabled because we are not properly parsing 3476 // linkage specifications on declarations, e.g., 3477 // 3478 // extern "C" const CGPoint CGPointerZero; 3479 // 3480 // C++ [dcl.init]p9: 3481 // 3482 // If no initializer is specified for an object, and the 3483 // object is of (possibly cv-qualified) non-POD class type (or 3484 // array thereof), the object shall be default-initialized; if 3485 // the object is of const-qualified type, the underlying class 3486 // type shall have a user-declared default 3487 // constructor. Otherwise, if no initializer is specified for 3488 // an object, the object and its subobjects, if any, have an 3489 // indeterminate initial value; if the object or any of its 3490 // subobjects are of const-qualified type, the program is 3491 // ill-formed. 3492 // 3493 // This isn't technically an error in C, so we don't diagnose it. 3494 // 3495 // FIXME: Actually perform the POD/user-defined default 3496 // constructor check. 3497 if (getLangOptions().CPlusPlus && 3498 Context.getCanonicalType(Type).isConstQualified() && 3499 !Var->hasExternalStorage()) 3500 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3501 << Var->getName() 3502 << SourceRange(Var->getLocation(), Var->getLocation()); 3503#endif 3504 } 3505} 3506 3507Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3508 DeclPtrTy *Group, 3509 unsigned NumDecls) { 3510 llvm::SmallVector<Decl*, 8> Decls; 3511 3512 if (DS.isTypeSpecOwned()) 3513 Decls.push_back((Decl*)DS.getTypeRep()); 3514 3515 for (unsigned i = 0; i != NumDecls; ++i) 3516 if (Decl *D = Group[i].getAs<Decl>()) 3517 Decls.push_back(D); 3518 3519 // Perform semantic analysis that depends on having fully processed both 3520 // the declarator and initializer. 3521 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3522 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3523 if (!IDecl) 3524 continue; 3525 QualType T = IDecl->getType(); 3526 3527 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3528 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3529 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3530 if (!IDecl->isInvalidDecl() && 3531 RequireCompleteType(IDecl->getLocation(), T, 3532 diag::err_typecheck_decl_incomplete_type)) 3533 IDecl->setInvalidDecl(); 3534 } 3535 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3536 // object that has file scope without an initializer, and without a 3537 // storage-class specifier or with the storage-class specifier "static", 3538 // constitutes a tentative definition. Note: A tentative definition with 3539 // external linkage is valid (C99 6.2.2p5). 3540 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3541 if (const IncompleteArrayType *ArrayT 3542 = Context.getAsIncompleteArrayType(T)) { 3543 if (RequireCompleteType(IDecl->getLocation(), 3544 ArrayT->getElementType(), 3545 diag::err_illegal_decl_array_incomplete_type)) 3546 IDecl->setInvalidDecl(); 3547 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3548 // C99 6.9.2p3: If the declaration of an identifier for an object is 3549 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3550 // declared type shall not be an incomplete type. 3551 // NOTE: code such as the following 3552 // static struct s; 3553 // struct s { int a; }; 3554 // is accepted by gcc. Hence here we issue a warning instead of 3555 // an error and we do not invalidate the static declaration. 3556 // NOTE: to avoid multiple warnings, only check the first declaration. 3557 if (IDecl->getPreviousDeclaration() == 0) 3558 RequireCompleteType(IDecl->getLocation(), T, 3559 diag::ext_typecheck_decl_incomplete_type); 3560 } 3561 } 3562 } 3563 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3564 Decls.data(), Decls.size())); 3565} 3566 3567 3568/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3569/// to introduce parameters into function prototype scope. 3570Sema::DeclPtrTy 3571Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3572 const DeclSpec &DS = D.getDeclSpec(); 3573 3574 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3575 VarDecl::StorageClass StorageClass = VarDecl::None; 3576 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3577 StorageClass = VarDecl::Register; 3578 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3579 Diag(DS.getStorageClassSpecLoc(), 3580 diag::err_invalid_storage_class_in_func_decl); 3581 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3582 } 3583 3584 if (D.getDeclSpec().isThreadSpecified()) 3585 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3586 3587 DiagnoseFunctionSpecifiers(D); 3588 3589 // Check that there are no default arguments inside the type of this 3590 // parameter (C++ only). 3591 if (getLangOptions().CPlusPlus) 3592 CheckExtraCXXDefaultArguments(D); 3593 3594 DeclaratorInfo *DInfo = 0; 3595 TagDecl *OwnedDecl = 0; 3596 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3597 &OwnedDecl); 3598 3599 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3600 // C++ [dcl.fct]p6: 3601 // Types shall not be defined in return or parameter types. 3602 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3603 << Context.getTypeDeclType(OwnedDecl); 3604 } 3605 3606 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3607 // Can this happen for params? We already checked that they don't conflict 3608 // among each other. Here they can only shadow globals, which is ok. 3609 IdentifierInfo *II = D.getIdentifier(); 3610 if (II) { 3611 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3612 if (PrevDecl->isTemplateParameter()) { 3613 // Maybe we will complain about the shadowed template parameter. 3614 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3615 // Just pretend that we didn't see the previous declaration. 3616 PrevDecl = 0; 3617 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3618 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3619 3620 // Recover by removing the name 3621 II = 0; 3622 D.SetIdentifier(0, D.getIdentifierLoc()); 3623 } 3624 } 3625 } 3626 3627 // Parameters can not be abstract class types. 3628 // For record types, this is done by the AbstractClassUsageDiagnoser once 3629 // the class has been completely parsed. 3630 if (!CurContext->isRecord() && 3631 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3632 diag::err_abstract_type_in_decl, 3633 AbstractParamType)) 3634 D.setInvalidType(true); 3635 3636 QualType T = adjustParameterType(parmDeclType); 3637 3638 ParmVarDecl *New; 3639 if (T == parmDeclType) // parameter type did not need adjustment 3640 New = ParmVarDecl::Create(Context, CurContext, 3641 D.getIdentifierLoc(), II, 3642 parmDeclType, DInfo, StorageClass, 3643 0); 3644 else // keep track of both the adjusted and unadjusted types 3645 New = OriginalParmVarDecl::Create(Context, CurContext, 3646 D.getIdentifierLoc(), II, T, DInfo, 3647 parmDeclType, StorageClass, 0); 3648 3649 if (D.isInvalidType()) 3650 New->setInvalidDecl(); 3651 3652 // Parameter declarators cannot be interface types. All ObjC objects are 3653 // passed by reference. 3654 if (T->isObjCInterfaceType()) { 3655 Diag(D.getIdentifierLoc(), 3656 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3657 New->setInvalidDecl(); 3658 } 3659 3660 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3661 if (D.getCXXScopeSpec().isSet()) { 3662 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3663 << D.getCXXScopeSpec().getRange(); 3664 New->setInvalidDecl(); 3665 } 3666 3667 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3668 // duration shall not be qualified by an address-space qualifier." 3669 // Since all parameters have automatic store duration, they can not have 3670 // an address space. 3671 if (T.getAddressSpace() != 0) { 3672 Diag(D.getIdentifierLoc(), 3673 diag::err_arg_with_address_space); 3674 New->setInvalidDecl(); 3675 } 3676 3677 3678 // Add the parameter declaration into this scope. 3679 S->AddDecl(DeclPtrTy::make(New)); 3680 if (II) 3681 IdResolver.AddDecl(New); 3682 3683 ProcessDeclAttributes(S, New, D); 3684 3685 if (New->hasAttr<BlocksAttr>()) { 3686 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3687 } 3688 return DeclPtrTy::make(New); 3689} 3690 3691void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3692 SourceLocation LocAfterDecls) { 3693 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3694 "Not a function declarator!"); 3695 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3696 3697 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3698 // for a K&R function. 3699 if (!FTI.hasPrototype) { 3700 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3701 --i; 3702 if (FTI.ArgInfo[i].Param == 0) { 3703 std::string Code = " int "; 3704 Code += FTI.ArgInfo[i].Ident->getName(); 3705 Code += ";\n"; 3706 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3707 << FTI.ArgInfo[i].Ident 3708 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 3709 3710 // Implicitly declare the argument as type 'int' for lack of a better 3711 // type. 3712 DeclSpec DS; 3713 const char* PrevSpec; // unused 3714 unsigned DiagID; // unused 3715 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3716 PrevSpec, DiagID); 3717 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3718 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3719 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3720 } 3721 } 3722 } 3723} 3724 3725Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3726 Declarator &D) { 3727 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3728 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3729 "Not a function declarator!"); 3730 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3731 3732 if (FTI.hasPrototype) { 3733 // FIXME: Diagnose arguments without names in C. 3734 } 3735 3736 Scope *ParentScope = FnBodyScope->getParent(); 3737 3738 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3739 MultiTemplateParamsArg(*this), 3740 /*IsFunctionDefinition=*/true); 3741 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3742} 3743 3744Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3745 if (!D) 3746 return D; 3747 FunctionDecl *FD = 0; 3748 3749 if (FunctionTemplateDecl *FunTmpl 3750 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3751 FD = FunTmpl->getTemplatedDecl(); 3752 else 3753 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3754 3755 CurFunctionNeedsScopeChecking = false; 3756 3757 // See if this is a redefinition. 3758 const FunctionDecl *Definition; 3759 if (FD->getBody(Definition)) { 3760 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3761 Diag(Definition->getLocation(), diag::note_previous_definition); 3762 } 3763 3764 // Builtin functions cannot be defined. 3765 if (unsigned BuiltinID = FD->getBuiltinID()) { 3766 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3767 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3768 FD->setInvalidDecl(); 3769 } 3770 } 3771 3772 // The return type of a function definition must be complete 3773 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3774 QualType ResultType = FD->getResultType(); 3775 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3776 !FD->isInvalidDecl() && 3777 RequireCompleteType(FD->getLocation(), ResultType, 3778 diag::err_func_def_incomplete_result)) 3779 FD->setInvalidDecl(); 3780 3781 // GNU warning -Wmissing-prototypes: 3782 // Warn if a global function is defined without a previous 3783 // prototype declaration. This warning is issued even if the 3784 // definition itself provides a prototype. The aim is to detect 3785 // global functions that fail to be declared in header files. 3786 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3787 !FD->isMain()) { 3788 bool MissingPrototype = true; 3789 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3790 Prev; Prev = Prev->getPreviousDeclaration()) { 3791 // Ignore any declarations that occur in function or method 3792 // scope, because they aren't visible from the header. 3793 if (Prev->getDeclContext()->isFunctionOrMethod()) 3794 continue; 3795 3796 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3797 break; 3798 } 3799 3800 if (MissingPrototype) 3801 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3802 } 3803 3804 if (FnBodyScope) 3805 PushDeclContext(FnBodyScope, FD); 3806 3807 // Check the validity of our function parameters 3808 CheckParmsForFunctionDef(FD); 3809 3810 // Introduce our parameters into the function scope 3811 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3812 ParmVarDecl *Param = FD->getParamDecl(p); 3813 Param->setOwningFunction(FD); 3814 3815 // If this has an identifier, add it to the scope stack. 3816 if (Param->getIdentifier() && FnBodyScope) 3817 PushOnScopeChains(Param, FnBodyScope); 3818 } 3819 3820 // Checking attributes of current function definition 3821 // dllimport attribute. 3822 if (FD->getAttr<DLLImportAttr>() && 3823 (!FD->getAttr<DLLExportAttr>())) { 3824 // dllimport attribute cannot be applied to definition. 3825 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3826 Diag(FD->getLocation(), 3827 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3828 << "dllimport"; 3829 FD->setInvalidDecl(); 3830 return DeclPtrTy::make(FD); 3831 } else { 3832 // If a symbol previously declared dllimport is later defined, the 3833 // attribute is ignored in subsequent references, and a warning is 3834 // emitted. 3835 Diag(FD->getLocation(), 3836 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3837 << FD->getNameAsCString() << "dllimport"; 3838 } 3839 } 3840 return DeclPtrTy::make(FD); 3841} 3842 3843Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3844 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3845} 3846 3847Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3848 bool IsInstantiation) { 3849 Decl *dcl = D.getAs<Decl>(); 3850 Stmt *Body = BodyArg.takeAs<Stmt>(); 3851 3852 FunctionDecl *FD = 0; 3853 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3854 if (FunTmpl) 3855 FD = FunTmpl->getTemplatedDecl(); 3856 else 3857 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3858 3859 if (FD) { 3860 FD->setBody(Body); 3861 if (FD->isMain()) 3862 // C and C++ allow for main to automagically return 0. 3863 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3864 FD->setHasImplicitReturnZero(true); 3865 else 3866 CheckFallThroughForFunctionDef(FD, Body); 3867 3868 if (!FD->isInvalidDecl()) 3869 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3870 3871 // C++ [basic.def.odr]p2: 3872 // [...] A virtual member function is used if it is not pure. [...] 3873 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3874 if (Method->isVirtual() && !Method->isPure()) 3875 MarkDeclarationReferenced(Method->getLocation(), Method); 3876 3877 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3878 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3879 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3880 MD->setBody(Body); 3881 CheckFallThroughForFunctionDef(MD, Body); 3882 MD->setEndLoc(Body->getLocEnd()); 3883 3884 if (!MD->isInvalidDecl()) 3885 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3886 } else { 3887 Body->Destroy(Context); 3888 return DeclPtrTy(); 3889 } 3890 if (!IsInstantiation) 3891 PopDeclContext(); 3892 3893 // Verify and clean out per-function state. 3894 3895 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3896 3897 // Check goto/label use. 3898 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3899 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3900 LabelStmt *L = I->second; 3901 3902 // Verify that we have no forward references left. If so, there was a goto 3903 // or address of a label taken, but no definition of it. Label fwd 3904 // definitions are indicated with a null substmt. 3905 if (L->getSubStmt() != 0) 3906 continue; 3907 3908 // Emit error. 3909 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3910 3911 // At this point, we have gotos that use the bogus label. Stitch it into 3912 // the function body so that they aren't leaked and that the AST is well 3913 // formed. 3914 if (Body == 0) { 3915 // The whole function wasn't parsed correctly, just delete this. 3916 L->Destroy(Context); 3917 continue; 3918 } 3919 3920 // Otherwise, the body is valid: we want to stitch the label decl into the 3921 // function somewhere so that it is properly owned and so that the goto 3922 // has a valid target. Do this by creating a new compound stmt with the 3923 // label in it. 3924 3925 // Give the label a sub-statement. 3926 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3927 3928 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3929 cast<CXXTryStmt>(Body)->getTryBlock() : 3930 cast<CompoundStmt>(Body); 3931 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3932 Elements.push_back(L); 3933 Compound->setStmts(Context, &Elements[0], Elements.size()); 3934 } 3935 FunctionLabelMap.clear(); 3936 3937 if (!Body) return D; 3938 3939 // Verify that that gotos and switch cases don't jump into scopes illegally. 3940 if (CurFunctionNeedsScopeChecking) 3941 DiagnoseInvalidJumps(Body); 3942 3943 // C++ constructors that have function-try-blocks can't have return 3944 // statements in the handlers of that block. (C++ [except.handle]p14) 3945 // Verify this. 3946 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3947 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3948 3949 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3950 computeBaseOrMembersToDestroy(Destructor); 3951 return D; 3952} 3953 3954/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3955/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3956NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3957 IdentifierInfo &II, Scope *S) { 3958 // Before we produce a declaration for an implicitly defined 3959 // function, see whether there was a locally-scoped declaration of 3960 // this name as a function or variable. If so, use that 3961 // (non-visible) declaration, and complain about it. 3962 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3963 = LocallyScopedExternalDecls.find(&II); 3964 if (Pos != LocallyScopedExternalDecls.end()) { 3965 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3966 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3967 return Pos->second; 3968 } 3969 3970 // Extension in C99. Legal in C90, but warn about it. 3971 if (II.getNameStr().startswith("__builtin_")) 3972 Diag(Loc, diag::warn_builtin_unknown) << &II; 3973 else if (getLangOptions().C99) 3974 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3975 else 3976 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3977 3978 // Set a Declarator for the implicit definition: int foo(); 3979 const char *Dummy; 3980 DeclSpec DS; 3981 unsigned DiagID; 3982 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 3983 Error = Error; // Silence warning. 3984 assert(!Error && "Error setting up implicit decl!"); 3985 Declarator D(DS, Declarator::BlockContext); 3986 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3987 0, 0, false, SourceLocation(), 3988 false, 0,0,0, Loc, Loc, D), 3989 SourceLocation()); 3990 D.SetIdentifier(&II, Loc); 3991 3992 // Insert this function into translation-unit scope. 3993 3994 DeclContext *PrevDC = CurContext; 3995 CurContext = Context.getTranslationUnitDecl(); 3996 3997 FunctionDecl *FD = 3998 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 3999 FD->setImplicit(); 4000 4001 CurContext = PrevDC; 4002 4003 AddKnownFunctionAttributes(FD); 4004 4005 return FD; 4006} 4007 4008/// \brief Adds any function attributes that we know a priori based on 4009/// the declaration of this function. 4010/// 4011/// These attributes can apply both to implicitly-declared builtins 4012/// (like __builtin___printf_chk) or to library-declared functions 4013/// like NSLog or printf. 4014void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4015 if (FD->isInvalidDecl()) 4016 return; 4017 4018 // If this is a built-in function, map its builtin attributes to 4019 // actual attributes. 4020 if (unsigned BuiltinID = FD->getBuiltinID()) { 4021 // Handle printf-formatting attributes. 4022 unsigned FormatIdx; 4023 bool HasVAListArg; 4024 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4025 if (!FD->getAttr<FormatAttr>()) 4026 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4027 HasVAListArg ? 0 : FormatIdx + 2)); 4028 } 4029 4030 // Mark const if we don't care about errno and that is the only 4031 // thing preventing the function from being const. This allows 4032 // IRgen to use LLVM intrinsics for such functions. 4033 if (!getLangOptions().MathErrno && 4034 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4035 if (!FD->getAttr<ConstAttr>()) 4036 FD->addAttr(::new (Context) ConstAttr()); 4037 } 4038 4039 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4040 FD->addAttr(::new (Context) NoReturnAttr()); 4041 } 4042 4043 IdentifierInfo *Name = FD->getIdentifier(); 4044 if (!Name) 4045 return; 4046 if ((!getLangOptions().CPlusPlus && 4047 FD->getDeclContext()->isTranslationUnit()) || 4048 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4049 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4050 LinkageSpecDecl::lang_c)) { 4051 // Okay: this could be a libc/libm/Objective-C function we know 4052 // about. 4053 } else 4054 return; 4055 4056 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4057 // FIXME: NSLog and NSLogv should be target specific 4058 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4059 // FIXME: We known better than our headers. 4060 const_cast<FormatAttr *>(Format)->setType("printf"); 4061 } else 4062 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4063 Name->isStr("NSLogv") ? 0 : 2)); 4064 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4065 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4066 // target-specific builtins, perhaps? 4067 if (!FD->getAttr<FormatAttr>()) 4068 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4069 Name->isStr("vasprintf") ? 0 : 3)); 4070 } 4071} 4072 4073TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 4074 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4075 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4076 4077 // Scope manipulation handled by caller. 4078 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4079 D.getIdentifierLoc(), 4080 D.getIdentifier(), 4081 T); 4082 4083 if (const TagType *TT = T->getAs<TagType>()) { 4084 TagDecl *TD = TT->getDecl(); 4085 4086 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4087 // keep track of the TypedefDecl. 4088 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4089 TD->setTypedefForAnonDecl(NewTD); 4090 } 4091 4092 if (D.isInvalidType()) 4093 NewTD->setInvalidDecl(); 4094 return NewTD; 4095} 4096 4097 4098/// \brief Determine whether a tag with a given kind is acceptable 4099/// as a redeclaration of the given tag declaration. 4100/// 4101/// \returns true if the new tag kind is acceptable, false otherwise. 4102bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4103 TagDecl::TagKind NewTag, 4104 SourceLocation NewTagLoc, 4105 const IdentifierInfo &Name) { 4106 // C++ [dcl.type.elab]p3: 4107 // The class-key or enum keyword present in the 4108 // elaborated-type-specifier shall agree in kind with the 4109 // declaration to which the name in theelaborated-type-specifier 4110 // refers. This rule also applies to the form of 4111 // elaborated-type-specifier that declares a class-name or 4112 // friend class since it can be construed as referring to the 4113 // definition of the class. Thus, in any 4114 // elaborated-type-specifier, the enum keyword shall be used to 4115 // refer to an enumeration (7.2), the union class-keyshall be 4116 // used to refer to a union (clause 9), and either the class or 4117 // struct class-key shall be used to refer to a class (clause 9) 4118 // declared using the class or struct class-key. 4119 TagDecl::TagKind OldTag = Previous->getTagKind(); 4120 if (OldTag == NewTag) 4121 return true; 4122 4123 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4124 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4125 // Warn about the struct/class tag mismatch. 4126 bool isTemplate = false; 4127 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4128 isTemplate = Record->getDescribedClassTemplate(); 4129 4130 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4131 << (NewTag == TagDecl::TK_class) 4132 << isTemplate << &Name 4133 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4134 OldTag == TagDecl::TK_class? "class" : "struct"); 4135 Diag(Previous->getLocation(), diag::note_previous_use); 4136 return true; 4137 } 4138 return false; 4139} 4140 4141/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4142/// former case, Name will be non-null. In the later case, Name will be null. 4143/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4144/// reference/declaration/definition of a tag. 4145Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4146 SourceLocation KWLoc, const CXXScopeSpec &SS, 4147 IdentifierInfo *Name, SourceLocation NameLoc, 4148 AttributeList *Attr, AccessSpecifier AS, 4149 MultiTemplateParamsArg TemplateParameterLists, 4150 bool &OwnedDecl, bool &IsDependent) { 4151 // If this is not a definition, it must have a name. 4152 assert((Name != 0 || TUK == TUK_Definition) && 4153 "Nameless record must be a definition!"); 4154 4155 OwnedDecl = false; 4156 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4157 4158 // FIXME: Check explicit specializations more carefully. 4159 bool isExplicitSpecialization = false; 4160 if (TUK != TUK_Reference) { 4161 if (TemplateParameterList *TemplateParams 4162 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4163 (TemplateParameterList**)TemplateParameterLists.get(), 4164 TemplateParameterLists.size(), 4165 isExplicitSpecialization)) { 4166 if (TemplateParams->size() > 0) { 4167 // This is a declaration or definition of a class template (which may 4168 // be a member of another template). 4169 OwnedDecl = false; 4170 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4171 SS, Name, NameLoc, Attr, 4172 TemplateParams, 4173 AS); 4174 TemplateParameterLists.release(); 4175 return Result.get(); 4176 } else { 4177 // The "template<>" header is extraneous. 4178 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4179 << ElaboratedType::getNameForTagKind(Kind) << Name; 4180 isExplicitSpecialization = true; 4181 } 4182 } 4183 4184 TemplateParameterLists.release(); 4185 } 4186 4187 DeclContext *SearchDC = CurContext; 4188 DeclContext *DC = CurContext; 4189 NamedDecl *PrevDecl = 0; 4190 bool isStdBadAlloc = false; 4191 bool Invalid = false; 4192 4193 bool RedeclarationOnly = (TUK != TUK_Reference); 4194 4195 if (Name && SS.isNotEmpty()) { 4196 // We have a nested-name tag ('struct foo::bar'). 4197 4198 // Check for invalid 'foo::'. 4199 if (SS.isInvalid()) { 4200 Name = 0; 4201 goto CreateNewDecl; 4202 } 4203 4204 // If this is a friend or a reference to a class in a dependent 4205 // context, don't try to make a decl for it. 4206 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4207 DC = computeDeclContext(SS, false); 4208 if (!DC) { 4209 IsDependent = true; 4210 return DeclPtrTy(); 4211 } 4212 } 4213 4214 if (RequireCompleteDeclContext(SS)) 4215 return DeclPtrTy::make((Decl *)0); 4216 4217 DC = computeDeclContext(SS, true); 4218 SearchDC = DC; 4219 // Look-up name inside 'foo::'. 4220 LookupResult R; 4221 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4222 4223 if (R.isAmbiguous()) { 4224 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4225 return DeclPtrTy(); 4226 } 4227 4228 if (R.getKind() == LookupResult::Found) 4229 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4230 4231 // A tag 'foo::bar' must already exist. 4232 if (!PrevDecl) { 4233 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4234 Name = 0; 4235 Invalid = true; 4236 goto CreateNewDecl; 4237 } 4238 } else if (Name) { 4239 // If this is a named struct, check to see if there was a previous forward 4240 // declaration or definition. 4241 // FIXME: We're looking into outer scopes here, even when we 4242 // shouldn't be. Doing so can result in ambiguities that we 4243 // shouldn't be diagnosing. 4244 LookupResult R; 4245 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4246 if (R.isAmbiguous()) { 4247 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4248 // FIXME: This is not best way to recover from case like: 4249 // 4250 // struct S s; 4251 // 4252 // causes needless "incomplete type" error later. 4253 Name = 0; 4254 PrevDecl = 0; 4255 Invalid = true; 4256 } else 4257 PrevDecl = R.getAsSingleDecl(Context); 4258 4259 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4260 // FIXME: This makes sure that we ignore the contexts associated 4261 // with C structs, unions, and enums when looking for a matching 4262 // tag declaration or definition. See the similar lookup tweak 4263 // in Sema::LookupName; is there a better way to deal with this? 4264 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4265 SearchDC = SearchDC->getParent(); 4266 } 4267 } 4268 4269 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4270 // Maybe we will complain about the shadowed template parameter. 4271 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4272 // Just pretend that we didn't see the previous declaration. 4273 PrevDecl = 0; 4274 } 4275 4276 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4277 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4278 // This is a declaration of or a reference to "std::bad_alloc". 4279 isStdBadAlloc = true; 4280 4281 if (!PrevDecl && StdBadAlloc) { 4282 // std::bad_alloc has been implicitly declared (but made invisible to 4283 // name lookup). Fill in this implicit declaration as the previous 4284 // declaration, so that the declarations get chained appropriately. 4285 PrevDecl = StdBadAlloc; 4286 } 4287 } 4288 4289 if (PrevDecl) { 4290 // Check whether the previous declaration is usable. 4291 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4292 4293 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4294 // If this is a use of a previous tag, or if the tag is already declared 4295 // in the same scope (so that the definition/declaration completes or 4296 // rementions the tag), reuse the decl. 4297 if (TUK == TUK_Reference || TUK == TUK_Friend || 4298 isDeclInScope(PrevDecl, SearchDC, S)) { 4299 // Make sure that this wasn't declared as an enum and now used as a 4300 // struct or something similar. 4301 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4302 bool SafeToContinue 4303 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4304 Kind != TagDecl::TK_enum); 4305 if (SafeToContinue) 4306 Diag(KWLoc, diag::err_use_with_wrong_tag) 4307 << Name 4308 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4309 PrevTagDecl->getKindName()); 4310 else 4311 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4312 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4313 4314 if (SafeToContinue) 4315 Kind = PrevTagDecl->getTagKind(); 4316 else { 4317 // Recover by making this an anonymous redefinition. 4318 Name = 0; 4319 PrevDecl = 0; 4320 Invalid = true; 4321 } 4322 } 4323 4324 if (!Invalid) { 4325 // If this is a use, just return the declaration we found. 4326 4327 // FIXME: In the future, return a variant or some other clue 4328 // for the consumer of this Decl to know it doesn't own it. 4329 // For our current ASTs this shouldn't be a problem, but will 4330 // need to be changed with DeclGroups. 4331 if (TUK == TUK_Reference || TUK == TUK_Friend) 4332 return DeclPtrTy::make(PrevDecl); 4333 4334 // Diagnose attempts to redefine a tag. 4335 if (TUK == TUK_Definition) { 4336 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4337 // If we're defining a specialization and the previous definition 4338 // is from an implicit instantiation, don't emit an error 4339 // here; we'll catch this in the general case below. 4340 if (!isExplicitSpecialization || 4341 !isa<CXXRecordDecl>(Def) || 4342 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4343 == TSK_ExplicitSpecialization) { 4344 Diag(NameLoc, diag::err_redefinition) << Name; 4345 Diag(Def->getLocation(), diag::note_previous_definition); 4346 // If this is a redefinition, recover by making this 4347 // struct be anonymous, which will make any later 4348 // references get the previous definition. 4349 Name = 0; 4350 PrevDecl = 0; 4351 Invalid = true; 4352 } 4353 } else { 4354 // If the type is currently being defined, complain 4355 // about a nested redefinition. 4356 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4357 if (Tag->isBeingDefined()) { 4358 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4359 Diag(PrevTagDecl->getLocation(), 4360 diag::note_previous_definition); 4361 Name = 0; 4362 PrevDecl = 0; 4363 Invalid = true; 4364 } 4365 } 4366 4367 // Okay, this is definition of a previously declared or referenced 4368 // tag PrevDecl. We're going to create a new Decl for it. 4369 } 4370 } 4371 // If we get here we have (another) forward declaration or we 4372 // have a definition. Just create a new decl. 4373 4374 } else { 4375 // If we get here, this is a definition of a new tag type in a nested 4376 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4377 // new decl/type. We set PrevDecl to NULL so that the entities 4378 // have distinct types. 4379 PrevDecl = 0; 4380 } 4381 // If we get here, we're going to create a new Decl. If PrevDecl 4382 // is non-NULL, it's a definition of the tag declared by 4383 // PrevDecl. If it's NULL, we have a new definition. 4384 } else { 4385 // PrevDecl is a namespace, template, or anything else 4386 // that lives in the IDNS_Tag identifier namespace. 4387 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4388 // The tag name clashes with a namespace name, issue an error and 4389 // recover by making this tag be anonymous. 4390 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4391 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4392 Name = 0; 4393 PrevDecl = 0; 4394 Invalid = true; 4395 } else { 4396 // The existing declaration isn't relevant to us; we're in a 4397 // new scope, so clear out the previous declaration. 4398 PrevDecl = 0; 4399 } 4400 } 4401 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4402 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4403 // C++ [basic.scope.pdecl]p5: 4404 // -- for an elaborated-type-specifier of the form 4405 // 4406 // class-key identifier 4407 // 4408 // if the elaborated-type-specifier is used in the 4409 // decl-specifier-seq or parameter-declaration-clause of a 4410 // function defined in namespace scope, the identifier is 4411 // declared as a class-name in the namespace that contains 4412 // the declaration; otherwise, except as a friend 4413 // declaration, the identifier is declared in the smallest 4414 // non-class, non-function-prototype scope that contains the 4415 // declaration. 4416 // 4417 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4418 // C structs and unions. 4419 // 4420 // GNU C also supports this behavior as part of its incomplete 4421 // enum types extension, while GNU C++ does not. 4422 // 4423 // Find the context where we'll be declaring the tag. 4424 // FIXME: We would like to maintain the current DeclContext as the 4425 // lexical context, 4426 while (SearchDC->isRecord()) 4427 SearchDC = SearchDC->getParent(); 4428 4429 // Find the scope where we'll be declaring the tag. 4430 while (S->isClassScope() || 4431 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4432 ((S->getFlags() & Scope::DeclScope) == 0) || 4433 (S->getEntity() && 4434 ((DeclContext *)S->getEntity())->isTransparentContext())) 4435 S = S->getParent(); 4436 4437 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4438 // C++ [namespace.memdef]p3: 4439 // If a friend declaration in a non-local class first declares a 4440 // class or function, the friend class or function is a member of 4441 // the innermost enclosing namespace. 4442 while (!SearchDC->isFileContext()) 4443 SearchDC = SearchDC->getParent(); 4444 4445 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4446 while (S->getEntity() != SearchDC) 4447 S = S->getParent(); 4448 } 4449 4450CreateNewDecl: 4451 4452 // If there is an identifier, use the location of the identifier as the 4453 // location of the decl, otherwise use the location of the struct/union 4454 // keyword. 4455 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4456 4457 // Otherwise, create a new declaration. If there is a previous 4458 // declaration of the same entity, the two will be linked via 4459 // PrevDecl. 4460 TagDecl *New; 4461 4462 if (Kind == TagDecl::TK_enum) { 4463 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4464 // enum X { A, B, C } D; D should chain to X. 4465 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4466 cast_or_null<EnumDecl>(PrevDecl)); 4467 // If this is an undefined enum, warn. 4468 if (TUK != TUK_Definition && !Invalid) { 4469 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4470 : diag::ext_forward_ref_enum; 4471 Diag(Loc, DK); 4472 } 4473 } else { 4474 // struct/union/class 4475 4476 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4477 // struct X { int A; } D; D should chain to X. 4478 if (getLangOptions().CPlusPlus) { 4479 // FIXME: Look for a way to use RecordDecl for simple structs. 4480 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4481 cast_or_null<CXXRecordDecl>(PrevDecl)); 4482 4483 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4484 StdBadAlloc = cast<CXXRecordDecl>(New); 4485 } else 4486 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4487 cast_or_null<RecordDecl>(PrevDecl)); 4488 } 4489 4490 if (Kind != TagDecl::TK_enum) { 4491 // Handle #pragma pack: if the #pragma pack stack has non-default 4492 // alignment, make up a packed attribute for this decl. These 4493 // attributes are checked when the ASTContext lays out the 4494 // structure. 4495 // 4496 // It is important for implementing the correct semantics that this 4497 // happen here (in act on tag decl). The #pragma pack stack is 4498 // maintained as a result of parser callbacks which can occur at 4499 // many points during the parsing of a struct declaration (because 4500 // the #pragma tokens are effectively skipped over during the 4501 // parsing of the struct). 4502 if (unsigned Alignment = getPragmaPackAlignment()) 4503 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4504 } 4505 4506 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4507 // C++ [dcl.typedef]p3: 4508 // [...] Similarly, in a given scope, a class or enumeration 4509 // shall not be declared with the same name as a typedef-name 4510 // that is declared in that scope and refers to a type other 4511 // than the class or enumeration itself. 4512 LookupResult Lookup; 4513 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4514 TypedefDecl *PrevTypedef = 0; 4515 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4516 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4517 4518 NamedDecl *PrevTypedefNamed = PrevTypedef; 4519 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4520 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4521 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4522 Diag(Loc, diag::err_tag_definition_of_typedef) 4523 << Context.getTypeDeclType(New) 4524 << PrevTypedef->getUnderlyingType(); 4525 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4526 Invalid = true; 4527 } 4528 } 4529 4530 // If this is a specialization of a member class (of a class template), 4531 // check the specialization. 4532 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4533 Invalid = true; 4534 4535 if (Invalid) 4536 New->setInvalidDecl(); 4537 4538 if (Attr) 4539 ProcessDeclAttributeList(S, New, Attr); 4540 4541 // If we're declaring or defining a tag in function prototype scope 4542 // in C, note that this type can only be used within the function. 4543 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4544 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4545 4546 // Set the lexical context. If the tag has a C++ scope specifier, the 4547 // lexical context will be different from the semantic context. 4548 New->setLexicalDeclContext(CurContext); 4549 4550 // Mark this as a friend decl if applicable. 4551 if (TUK == TUK_Friend) 4552 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4553 4554 // Set the access specifier. 4555 if (!Invalid && TUK != TUK_Friend) 4556 SetMemberAccessSpecifier(New, PrevDecl, AS); 4557 4558 if (TUK == TUK_Definition) 4559 New->startDefinition(); 4560 4561 // If this has an identifier, add it to the scope stack. 4562 if (TUK == TUK_Friend) { 4563 // We might be replacing an existing declaration in the lookup tables; 4564 // if so, borrow its access specifier. 4565 if (PrevDecl) 4566 New->setAccess(PrevDecl->getAccess()); 4567 4568 // Friend tag decls are visible in fairly strange ways. 4569 if (!CurContext->isDependentContext()) { 4570 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4571 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4572 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4573 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4574 } 4575 } else if (Name) { 4576 S = getNonFieldDeclScope(S); 4577 PushOnScopeChains(New, S); 4578 } else { 4579 CurContext->addDecl(New); 4580 } 4581 4582 // If this is the C FILE type, notify the AST context. 4583 if (IdentifierInfo *II = New->getIdentifier()) 4584 if (!New->isInvalidDecl() && 4585 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4586 II->isStr("FILE")) 4587 Context.setFILEDecl(New); 4588 4589 OwnedDecl = true; 4590 return DeclPtrTy::make(New); 4591} 4592 4593void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4594 AdjustDeclIfTemplate(TagD); 4595 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4596 4597 // Enter the tag context. 4598 PushDeclContext(S, Tag); 4599 4600 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4601 FieldCollector->StartClass(); 4602 4603 if (Record->getIdentifier()) { 4604 // C++ [class]p2: 4605 // [...] The class-name is also inserted into the scope of the 4606 // class itself; this is known as the injected-class-name. For 4607 // purposes of access checking, the injected-class-name is treated 4608 // as if it were a public member name. 4609 CXXRecordDecl *InjectedClassName 4610 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4611 CurContext, Record->getLocation(), 4612 Record->getIdentifier(), 4613 Record->getTagKeywordLoc(), 4614 Record); 4615 InjectedClassName->setImplicit(); 4616 InjectedClassName->setAccess(AS_public); 4617 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4618 InjectedClassName->setDescribedClassTemplate(Template); 4619 PushOnScopeChains(InjectedClassName, S); 4620 assert(InjectedClassName->isInjectedClassName() && 4621 "Broken injected-class-name"); 4622 } 4623 } 4624} 4625 4626void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4627 SourceLocation RBraceLoc) { 4628 AdjustDeclIfTemplate(TagD); 4629 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4630 Tag->setRBraceLoc(RBraceLoc); 4631 4632 if (isa<CXXRecordDecl>(Tag)) 4633 FieldCollector->FinishClass(); 4634 4635 // Exit this scope of this tag's definition. 4636 PopDeclContext(); 4637 4638 // Notify the consumer that we've defined a tag. 4639 Consumer.HandleTagDeclDefinition(Tag); 4640} 4641 4642// Note that FieldName may be null for anonymous bitfields. 4643bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4644 QualType FieldTy, const Expr *BitWidth, 4645 bool *ZeroWidth) { 4646 // Default to true; that shouldn't confuse checks for emptiness 4647 if (ZeroWidth) 4648 *ZeroWidth = true; 4649 4650 // C99 6.7.2.1p4 - verify the field type. 4651 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4652 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4653 // Handle incomplete types with specific error. 4654 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4655 return true; 4656 if (FieldName) 4657 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4658 << FieldName << FieldTy << BitWidth->getSourceRange(); 4659 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4660 << FieldTy << BitWidth->getSourceRange(); 4661 } 4662 4663 // If the bit-width is type- or value-dependent, don't try to check 4664 // it now. 4665 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4666 return false; 4667 4668 llvm::APSInt Value; 4669 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4670 return true; 4671 4672 if (Value != 0 && ZeroWidth) 4673 *ZeroWidth = false; 4674 4675 // Zero-width bitfield is ok for anonymous field. 4676 if (Value == 0 && FieldName) 4677 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4678 4679 if (Value.isSigned() && Value.isNegative()) { 4680 if (FieldName) 4681 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4682 << FieldName << Value.toString(10); 4683 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4684 << Value.toString(10); 4685 } 4686 4687 if (!FieldTy->isDependentType()) { 4688 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4689 if (Value.getZExtValue() > TypeSize) { 4690 if (FieldName) 4691 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4692 << FieldName << (unsigned)TypeSize; 4693 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4694 << (unsigned)TypeSize; 4695 } 4696 } 4697 4698 return false; 4699} 4700 4701/// ActOnField - Each field of a struct/union/class is passed into this in order 4702/// to create a FieldDecl object for it. 4703Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4704 SourceLocation DeclStart, 4705 Declarator &D, ExprTy *BitfieldWidth) { 4706 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4707 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4708 AS_public); 4709 return DeclPtrTy::make(Res); 4710} 4711 4712/// HandleField - Analyze a field of a C struct or a C++ data member. 4713/// 4714FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4715 SourceLocation DeclStart, 4716 Declarator &D, Expr *BitWidth, 4717 AccessSpecifier AS) { 4718 IdentifierInfo *II = D.getIdentifier(); 4719 SourceLocation Loc = DeclStart; 4720 if (II) Loc = D.getIdentifierLoc(); 4721 4722 DeclaratorInfo *DInfo = 0; 4723 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4724 if (getLangOptions().CPlusPlus) 4725 CheckExtraCXXDefaultArguments(D); 4726 4727 DiagnoseFunctionSpecifiers(D); 4728 4729 if (D.getDeclSpec().isThreadSpecified()) 4730 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4731 4732 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4733 4734 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4735 // Maybe we will complain about the shadowed template parameter. 4736 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4737 // Just pretend that we didn't see the previous declaration. 4738 PrevDecl = 0; 4739 } 4740 4741 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4742 PrevDecl = 0; 4743 4744 bool Mutable 4745 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4746 SourceLocation TSSL = D.getSourceRange().getBegin(); 4747 FieldDecl *NewFD 4748 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4749 AS, PrevDecl, &D); 4750 if (NewFD->isInvalidDecl() && PrevDecl) { 4751 // Don't introduce NewFD into scope; there's already something 4752 // with the same name in the same scope. 4753 } else if (II) { 4754 PushOnScopeChains(NewFD, S); 4755 } else 4756 Record->addDecl(NewFD); 4757 4758 return NewFD; 4759} 4760 4761/// \brief Build a new FieldDecl and check its well-formedness. 4762/// 4763/// This routine builds a new FieldDecl given the fields name, type, 4764/// record, etc. \p PrevDecl should refer to any previous declaration 4765/// with the same name and in the same scope as the field to be 4766/// created. 4767/// 4768/// \returns a new FieldDecl. 4769/// 4770/// \todo The Declarator argument is a hack. It will be removed once 4771FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4772 DeclaratorInfo *DInfo, 4773 RecordDecl *Record, SourceLocation Loc, 4774 bool Mutable, Expr *BitWidth, 4775 SourceLocation TSSL, 4776 AccessSpecifier AS, NamedDecl *PrevDecl, 4777 Declarator *D) { 4778 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4779 bool InvalidDecl = false; 4780 if (D) InvalidDecl = D->isInvalidType(); 4781 4782 // If we receive a broken type, recover by assuming 'int' and 4783 // marking this declaration as invalid. 4784 if (T.isNull()) { 4785 InvalidDecl = true; 4786 T = Context.IntTy; 4787 } 4788 4789 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4790 // than a variably modified type. 4791 if (T->isVariablyModifiedType()) { 4792 bool SizeIsNegative; 4793 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4794 SizeIsNegative); 4795 if (!FixedTy.isNull()) { 4796 Diag(Loc, diag::warn_illegal_constant_array_size); 4797 T = FixedTy; 4798 } else { 4799 if (SizeIsNegative) 4800 Diag(Loc, diag::err_typecheck_negative_array_size); 4801 else 4802 Diag(Loc, diag::err_typecheck_field_variable_size); 4803 InvalidDecl = true; 4804 } 4805 } 4806 4807 // Fields can not have abstract class types 4808 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4809 AbstractFieldType)) 4810 InvalidDecl = true; 4811 4812 bool ZeroWidth = false; 4813 // If this is declared as a bit-field, check the bit-field. 4814 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4815 InvalidDecl = true; 4816 DeleteExpr(BitWidth); 4817 BitWidth = 0; 4818 ZeroWidth = false; 4819 } 4820 4821 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4822 BitWidth, Mutable); 4823 if (InvalidDecl) 4824 NewFD->setInvalidDecl(); 4825 4826 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4827 Diag(Loc, diag::err_duplicate_member) << II; 4828 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4829 NewFD->setInvalidDecl(); 4830 } 4831 4832 if (getLangOptions().CPlusPlus) { 4833 QualType EltTy = Context.getBaseElementType(T); 4834 4835 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4836 4837 if (!T->isPODType()) 4838 CXXRecord->setPOD(false); 4839 if (!ZeroWidth) 4840 CXXRecord->setEmpty(false); 4841 4842 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4843 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4844 4845 if (!RDecl->hasTrivialConstructor()) 4846 CXXRecord->setHasTrivialConstructor(false); 4847 if (!RDecl->hasTrivialCopyConstructor()) 4848 CXXRecord->setHasTrivialCopyConstructor(false); 4849 if (!RDecl->hasTrivialCopyAssignment()) 4850 CXXRecord->setHasTrivialCopyAssignment(false); 4851 if (!RDecl->hasTrivialDestructor()) 4852 CXXRecord->setHasTrivialDestructor(false); 4853 4854 // C++ 9.5p1: An object of a class with a non-trivial 4855 // constructor, a non-trivial copy constructor, a non-trivial 4856 // destructor, or a non-trivial copy assignment operator 4857 // cannot be a member of a union, nor can an array of such 4858 // objects. 4859 // TODO: C++0x alters this restriction significantly. 4860 if (Record->isUnion()) { 4861 // We check for copy constructors before constructors 4862 // because otherwise we'll never get complaints about 4863 // copy constructors. 4864 4865 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4866 4867 CXXSpecialMember member; 4868 if (!RDecl->hasTrivialCopyConstructor()) 4869 member = CXXCopyConstructor; 4870 else if (!RDecl->hasTrivialConstructor()) 4871 member = CXXDefaultConstructor; 4872 else if (!RDecl->hasTrivialCopyAssignment()) 4873 member = CXXCopyAssignment; 4874 else if (!RDecl->hasTrivialDestructor()) 4875 member = CXXDestructor; 4876 else 4877 member = invalid; 4878 4879 if (member != invalid) { 4880 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4881 DiagnoseNontrivial(RT, member); 4882 NewFD->setInvalidDecl(); 4883 } 4884 } 4885 } 4886 } 4887 4888 // FIXME: We need to pass in the attributes given an AST 4889 // representation, not a parser representation. 4890 if (D) 4891 // FIXME: What to pass instead of TUScope? 4892 ProcessDeclAttributes(TUScope, NewFD, *D); 4893 4894 if (T.isObjCGCWeak()) 4895 Diag(Loc, diag::warn_attribute_weak_on_field); 4896 4897 NewFD->setAccess(AS); 4898 4899 // C++ [dcl.init.aggr]p1: 4900 // An aggregate is an array or a class (clause 9) with [...] no 4901 // private or protected non-static data members (clause 11). 4902 // A POD must be an aggregate. 4903 if (getLangOptions().CPlusPlus && 4904 (AS == AS_private || AS == AS_protected)) { 4905 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4906 CXXRecord->setAggregate(false); 4907 CXXRecord->setPOD(false); 4908 } 4909 4910 return NewFD; 4911} 4912 4913/// DiagnoseNontrivial - Given that a class has a non-trivial 4914/// special member, figure out why. 4915void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4916 QualType QT(T, 0U); 4917 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4918 4919 // Check whether the member was user-declared. 4920 switch (member) { 4921 case CXXDefaultConstructor: 4922 if (RD->hasUserDeclaredConstructor()) { 4923 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4924 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4925 if (!ci->isImplicitlyDefined(Context)) { 4926 SourceLocation CtorLoc = ci->getLocation(); 4927 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4928 return; 4929 } 4930 4931 assert(0 && "found no user-declared constructors"); 4932 return; 4933 } 4934 break; 4935 4936 case CXXCopyConstructor: 4937 if (RD->hasUserDeclaredCopyConstructor()) { 4938 SourceLocation CtorLoc = 4939 RD->getCopyConstructor(Context, 0)->getLocation(); 4940 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4941 return; 4942 } 4943 break; 4944 4945 case CXXCopyAssignment: 4946 if (RD->hasUserDeclaredCopyAssignment()) { 4947 // FIXME: this should use the location of the copy 4948 // assignment, not the type. 4949 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4950 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4951 return; 4952 } 4953 break; 4954 4955 case CXXDestructor: 4956 if (RD->hasUserDeclaredDestructor()) { 4957 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4958 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4959 return; 4960 } 4961 break; 4962 } 4963 4964 typedef CXXRecordDecl::base_class_iterator base_iter; 4965 4966 // Virtual bases and members inhibit trivial copying/construction, 4967 // but not trivial destruction. 4968 if (member != CXXDestructor) { 4969 // Check for virtual bases. vbases includes indirect virtual bases, 4970 // so we just iterate through the direct bases. 4971 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4972 if (bi->isVirtual()) { 4973 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 4974 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 4975 return; 4976 } 4977 4978 // Check for virtual methods. 4979 typedef CXXRecordDecl::method_iterator meth_iter; 4980 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 4981 ++mi) { 4982 if (mi->isVirtual()) { 4983 SourceLocation MLoc = mi->getSourceRange().getBegin(); 4984 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 4985 return; 4986 } 4987 } 4988 } 4989 4990 bool (CXXRecordDecl::*hasTrivial)() const; 4991 switch (member) { 4992 case CXXDefaultConstructor: 4993 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 4994 case CXXCopyConstructor: 4995 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 4996 case CXXCopyAssignment: 4997 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 4998 case CXXDestructor: 4999 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5000 default: 5001 assert(0 && "unexpected special member"); return; 5002 } 5003 5004 // Check for nontrivial bases (and recurse). 5005 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5006 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5007 assert(BaseRT); 5008 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5009 if (!(BaseRecTy->*hasTrivial)()) { 5010 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5011 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5012 DiagnoseNontrivial(BaseRT, member); 5013 return; 5014 } 5015 } 5016 5017 // Check for nontrivial members (and recurse). 5018 typedef RecordDecl::field_iterator field_iter; 5019 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5020 ++fi) { 5021 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5022 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5023 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5024 5025 if (!(EltRD->*hasTrivial)()) { 5026 SourceLocation FLoc = (*fi)->getLocation(); 5027 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5028 DiagnoseNontrivial(EltRT, member); 5029 return; 5030 } 5031 } 5032 } 5033 5034 assert(0 && "found no explanation for non-trivial member"); 5035} 5036 5037/// TranslateIvarVisibility - Translate visibility from a token ID to an 5038/// AST enum value. 5039static ObjCIvarDecl::AccessControl 5040TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5041 switch (ivarVisibility) { 5042 default: assert(0 && "Unknown visitibility kind"); 5043 case tok::objc_private: return ObjCIvarDecl::Private; 5044 case tok::objc_public: return ObjCIvarDecl::Public; 5045 case tok::objc_protected: return ObjCIvarDecl::Protected; 5046 case tok::objc_package: return ObjCIvarDecl::Package; 5047 } 5048} 5049 5050/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5051/// in order to create an IvarDecl object for it. 5052Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5053 SourceLocation DeclStart, 5054 DeclPtrTy IntfDecl, 5055 Declarator &D, ExprTy *BitfieldWidth, 5056 tok::ObjCKeywordKind Visibility) { 5057 5058 IdentifierInfo *II = D.getIdentifier(); 5059 Expr *BitWidth = (Expr*)BitfieldWidth; 5060 SourceLocation Loc = DeclStart; 5061 if (II) Loc = D.getIdentifierLoc(); 5062 5063 // FIXME: Unnamed fields can be handled in various different ways, for 5064 // example, unnamed unions inject all members into the struct namespace! 5065 5066 DeclaratorInfo *DInfo = 0; 5067 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5068 5069 if (BitWidth) { 5070 // 6.7.2.1p3, 6.7.2.1p4 5071 if (VerifyBitField(Loc, II, T, BitWidth)) { 5072 D.setInvalidType(); 5073 DeleteExpr(BitWidth); 5074 BitWidth = 0; 5075 } 5076 } else { 5077 // Not a bitfield. 5078 5079 // validate II. 5080 5081 } 5082 5083 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5084 // than a variably modified type. 5085 if (T->isVariablyModifiedType()) { 5086 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5087 D.setInvalidType(); 5088 } 5089 5090 // Get the visibility (access control) for this ivar. 5091 ObjCIvarDecl::AccessControl ac = 5092 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5093 : ObjCIvarDecl::None; 5094 // Must set ivar's DeclContext to its enclosing interface. 5095 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5096 DeclContext *EnclosingContext; 5097 if (ObjCImplementationDecl *IMPDecl = 5098 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5099 // Case of ivar declared in an implementation. Context is that of its class. 5100 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5101 assert(IDecl && "No class- ActOnIvar"); 5102 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5103 } else 5104 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5105 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5106 5107 // Construct the decl. 5108 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5109 EnclosingContext, Loc, II, T, 5110 DInfo, ac, (Expr *)BitfieldWidth); 5111 5112 if (II) { 5113 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5114 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5115 && !isa<TagDecl>(PrevDecl)) { 5116 Diag(Loc, diag::err_duplicate_member) << II; 5117 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5118 NewID->setInvalidDecl(); 5119 } 5120 } 5121 5122 // Process attributes attached to the ivar. 5123 ProcessDeclAttributes(S, NewID, D); 5124 5125 if (D.isInvalidType()) 5126 NewID->setInvalidDecl(); 5127 5128 if (II) { 5129 // FIXME: When interfaces are DeclContexts, we'll need to add 5130 // these to the interface. 5131 S->AddDecl(DeclPtrTy::make(NewID)); 5132 IdResolver.AddDecl(NewID); 5133 } 5134 5135 return DeclPtrTy::make(NewID); 5136} 5137 5138void Sema::ActOnFields(Scope* S, 5139 SourceLocation RecLoc, DeclPtrTy RecDecl, 5140 DeclPtrTy *Fields, unsigned NumFields, 5141 SourceLocation LBrac, SourceLocation RBrac, 5142 AttributeList *Attr) { 5143 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5144 assert(EnclosingDecl && "missing record or interface decl"); 5145 5146 // If the decl this is being inserted into is invalid, then it may be a 5147 // redeclaration or some other bogus case. Don't try to add fields to it. 5148 if (EnclosingDecl->isInvalidDecl()) { 5149 // FIXME: Deallocate fields? 5150 return; 5151 } 5152 5153 5154 // Verify that all the fields are okay. 5155 unsigned NumNamedMembers = 0; 5156 llvm::SmallVector<FieldDecl*, 32> RecFields; 5157 5158 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5159 for (unsigned i = 0; i != NumFields; ++i) { 5160 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5161 5162 // Get the type for the field. 5163 Type *FDTy = FD->getType().getTypePtr(); 5164 5165 if (!FD->isAnonymousStructOrUnion()) { 5166 // Remember all fields written by the user. 5167 RecFields.push_back(FD); 5168 } 5169 5170 // If the field is already invalid for some reason, don't emit more 5171 // diagnostics about it. 5172 if (FD->isInvalidDecl()) 5173 continue; 5174 5175 // C99 6.7.2.1p2: 5176 // A structure or union shall not contain a member with 5177 // incomplete or function type (hence, a structure shall not 5178 // contain an instance of itself, but may contain a pointer to 5179 // an instance of itself), except that the last member of a 5180 // structure with more than one named member may have incomplete 5181 // array type; such a structure (and any union containing, 5182 // possibly recursively, a member that is such a structure) 5183 // shall not be a member of a structure or an element of an 5184 // array. 5185 if (FDTy->isFunctionType()) { 5186 // Field declared as a function. 5187 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5188 << FD->getDeclName(); 5189 FD->setInvalidDecl(); 5190 EnclosingDecl->setInvalidDecl(); 5191 continue; 5192 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5193 Record && Record->isStruct()) { 5194 // Flexible array member. 5195 if (NumNamedMembers < 1) { 5196 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5197 << FD->getDeclName(); 5198 FD->setInvalidDecl(); 5199 EnclosingDecl->setInvalidDecl(); 5200 continue; 5201 } 5202 // Okay, we have a legal flexible array member at the end of the struct. 5203 if (Record) 5204 Record->setHasFlexibleArrayMember(true); 5205 } else if (!FDTy->isDependentType() && 5206 RequireCompleteType(FD->getLocation(), FD->getType(), 5207 diag::err_field_incomplete)) { 5208 // Incomplete type 5209 FD->setInvalidDecl(); 5210 EnclosingDecl->setInvalidDecl(); 5211 continue; 5212 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5213 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5214 // If this is a member of a union, then entire union becomes "flexible". 5215 if (Record && Record->isUnion()) { 5216 Record->setHasFlexibleArrayMember(true); 5217 } else { 5218 // If this is a struct/class and this is not the last element, reject 5219 // it. Note that GCC supports variable sized arrays in the middle of 5220 // structures. 5221 if (i != NumFields-1) 5222 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5223 << FD->getDeclName() << FD->getType(); 5224 else { 5225 // We support flexible arrays at the end of structs in 5226 // other structs as an extension. 5227 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5228 << FD->getDeclName(); 5229 if (Record) 5230 Record->setHasFlexibleArrayMember(true); 5231 } 5232 } 5233 } 5234 if (Record && FDTTy->getDecl()->hasObjectMember()) 5235 Record->setHasObjectMember(true); 5236 } else if (FDTy->isObjCInterfaceType()) { 5237 /// A field cannot be an Objective-c object 5238 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5239 FD->setInvalidDecl(); 5240 EnclosingDecl->setInvalidDecl(); 5241 continue; 5242 } else if (getLangOptions().ObjC1 && 5243 getLangOptions().getGCMode() != LangOptions::NonGC && 5244 Record && 5245 (FD->getType()->isObjCObjectPointerType() || 5246 FD->getType().isObjCGCStrong())) 5247 Record->setHasObjectMember(true); 5248 // Keep track of the number of named members. 5249 if (FD->getIdentifier()) 5250 ++NumNamedMembers; 5251 } 5252 5253 // Okay, we successfully defined 'Record'. 5254 if (Record) { 5255 Record->completeDefinition(Context); 5256 } else { 5257 ObjCIvarDecl **ClsFields = 5258 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5259 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5260 ID->setIVarList(ClsFields, RecFields.size(), Context); 5261 ID->setLocEnd(RBrac); 5262 // Add ivar's to class's DeclContext. 5263 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5264 ClsFields[i]->setLexicalDeclContext(ID); 5265 ID->addDecl(ClsFields[i]); 5266 } 5267 // Must enforce the rule that ivars in the base classes may not be 5268 // duplicates. 5269 if (ID->getSuperClass()) { 5270 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5271 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5272 ObjCIvarDecl* Ivar = (*IVI); 5273 5274 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5275 ObjCIvarDecl* prevIvar = 5276 ID->getSuperClass()->lookupInstanceVariable(II); 5277 if (prevIvar) { 5278 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5279 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5280 } 5281 } 5282 } 5283 } 5284 } else if (ObjCImplementationDecl *IMPDecl = 5285 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5286 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5287 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5288 // Ivar declared in @implementation never belongs to the implementation. 5289 // Only it is in implementation's lexical context. 5290 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5291 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5292 } 5293 } 5294 5295 if (Attr) 5296 ProcessDeclAttributeList(S, Record, Attr); 5297} 5298 5299EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5300 EnumConstantDecl *LastEnumConst, 5301 SourceLocation IdLoc, 5302 IdentifierInfo *Id, 5303 ExprArg val) { 5304 Expr *Val = (Expr *)val.get(); 5305 5306 llvm::APSInt EnumVal(32); 5307 QualType EltTy; 5308 if (Val && !Val->isTypeDependent()) { 5309 // Make sure to promote the operand type to int. 5310 UsualUnaryConversions(Val); 5311 if (Val != val.get()) { 5312 val.release(); 5313 val = Val; 5314 } 5315 5316 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5317 SourceLocation ExpLoc; 5318 if (!Val->isValueDependent() && 5319 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5320 Val = 0; 5321 } else { 5322 EltTy = Val->getType(); 5323 } 5324 } 5325 5326 if (!Val) { 5327 if (LastEnumConst) { 5328 // Assign the last value + 1. 5329 EnumVal = LastEnumConst->getInitVal(); 5330 ++EnumVal; 5331 5332 // Check for overflow on increment. 5333 if (EnumVal < LastEnumConst->getInitVal()) 5334 Diag(IdLoc, diag::warn_enum_value_overflow); 5335 5336 EltTy = LastEnumConst->getType(); 5337 } else { 5338 // First value, set to zero. 5339 EltTy = Context.IntTy; 5340 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5341 } 5342 } 5343 5344 val.release(); 5345 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5346 Val, EnumVal); 5347} 5348 5349 5350Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5351 DeclPtrTy lastEnumConst, 5352 SourceLocation IdLoc, 5353 IdentifierInfo *Id, 5354 SourceLocation EqualLoc, ExprTy *val) { 5355 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5356 EnumConstantDecl *LastEnumConst = 5357 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5358 Expr *Val = static_cast<Expr*>(val); 5359 5360 // The scope passed in may not be a decl scope. Zip up the scope tree until 5361 // we find one that is. 5362 S = getNonFieldDeclScope(S); 5363 5364 // Verify that there isn't already something declared with this name in this 5365 // scope. 5366 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5367 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5368 // Maybe we will complain about the shadowed template parameter. 5369 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5370 // Just pretend that we didn't see the previous declaration. 5371 PrevDecl = 0; 5372 } 5373 5374 if (PrevDecl) { 5375 // When in C++, we may get a TagDecl with the same name; in this case the 5376 // enum constant will 'hide' the tag. 5377 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5378 "Received TagDecl when not in C++!"); 5379 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5380 if (isa<EnumConstantDecl>(PrevDecl)) 5381 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5382 else 5383 Diag(IdLoc, diag::err_redefinition) << Id; 5384 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5385 if (Val) Val->Destroy(Context); 5386 return DeclPtrTy(); 5387 } 5388 } 5389 5390 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5391 IdLoc, Id, Owned(Val)); 5392 5393 // Register this decl in the current scope stack. 5394 if (New) 5395 PushOnScopeChains(New, S); 5396 5397 return DeclPtrTy::make(New); 5398} 5399 5400void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5401 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5402 DeclPtrTy *Elements, unsigned NumElements, 5403 Scope *S, AttributeList *Attr) { 5404 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5405 QualType EnumType = Context.getTypeDeclType(Enum); 5406 5407 if (Attr) 5408 ProcessDeclAttributeList(S, Enum, Attr); 5409 5410 // TODO: If the result value doesn't fit in an int, it must be a long or long 5411 // long value. ISO C does not support this, but GCC does as an extension, 5412 // emit a warning. 5413 unsigned IntWidth = Context.Target.getIntWidth(); 5414 unsigned CharWidth = Context.Target.getCharWidth(); 5415 unsigned ShortWidth = Context.Target.getShortWidth(); 5416 5417 // Verify that all the values are okay, compute the size of the values, and 5418 // reverse the list. 5419 unsigned NumNegativeBits = 0; 5420 unsigned NumPositiveBits = 0; 5421 5422 // Keep track of whether all elements have type int. 5423 bool AllElementsInt = true; 5424 5425 for (unsigned i = 0; i != NumElements; ++i) { 5426 EnumConstantDecl *ECD = 5427 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5428 if (!ECD) continue; // Already issued a diagnostic. 5429 5430 // If the enum value doesn't fit in an int, emit an extension warning. 5431 const llvm::APSInt &InitVal = ECD->getInitVal(); 5432 assert(InitVal.getBitWidth() >= IntWidth && 5433 "Should have promoted value to int"); 5434 if (InitVal.getBitWidth() > IntWidth) { 5435 llvm::APSInt V(InitVal); 5436 V.trunc(IntWidth); 5437 V.extend(InitVal.getBitWidth()); 5438 if (V != InitVal) 5439 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5440 << InitVal.toString(10); 5441 } 5442 5443 // Keep track of the size of positive and negative values. 5444 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5445 NumPositiveBits = std::max(NumPositiveBits, 5446 (unsigned)InitVal.getActiveBits()); 5447 else 5448 NumNegativeBits = std::max(NumNegativeBits, 5449 (unsigned)InitVal.getMinSignedBits()); 5450 5451 // Keep track of whether every enum element has type int (very commmon). 5452 if (AllElementsInt) 5453 AllElementsInt = ECD->getType() == Context.IntTy; 5454 } 5455 5456 // Figure out the type that should be used for this enum. 5457 // FIXME: Support -fshort-enums. 5458 QualType BestType; 5459 unsigned BestWidth; 5460 5461 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5462 5463 if (NumNegativeBits) { 5464 // If there is a negative value, figure out the smallest integer type (of 5465 // int/long/longlong) that fits. 5466 // If it's packed, check also if it fits a char or a short. 5467 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5468 BestType = Context.SignedCharTy; 5469 BestWidth = CharWidth; 5470 } else if (Packed && NumNegativeBits <= ShortWidth && 5471 NumPositiveBits < ShortWidth) { 5472 BestType = Context.ShortTy; 5473 BestWidth = ShortWidth; 5474 } 5475 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5476 BestType = Context.IntTy; 5477 BestWidth = IntWidth; 5478 } else { 5479 BestWidth = Context.Target.getLongWidth(); 5480 5481 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5482 BestType = Context.LongTy; 5483 else { 5484 BestWidth = Context.Target.getLongLongWidth(); 5485 5486 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5487 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5488 BestType = Context.LongLongTy; 5489 } 5490 } 5491 } else { 5492 // If there is no negative value, figure out which of uint, ulong, ulonglong 5493 // fits. 5494 // If it's packed, check also if it fits a char or a short. 5495 if (Packed && NumPositiveBits <= CharWidth) { 5496 BestType = Context.UnsignedCharTy; 5497 BestWidth = CharWidth; 5498 } else if (Packed && NumPositiveBits <= ShortWidth) { 5499 BestType = Context.UnsignedShortTy; 5500 BestWidth = ShortWidth; 5501 } 5502 else if (NumPositiveBits <= IntWidth) { 5503 BestType = Context.UnsignedIntTy; 5504 BestWidth = IntWidth; 5505 } else if (NumPositiveBits <= 5506 (BestWidth = Context.Target.getLongWidth())) { 5507 BestType = Context.UnsignedLongTy; 5508 } else { 5509 BestWidth = Context.Target.getLongLongWidth(); 5510 assert(NumPositiveBits <= BestWidth && 5511 "How could an initializer get larger than ULL?"); 5512 BestType = Context.UnsignedLongLongTy; 5513 } 5514 } 5515 5516 // Loop over all of the enumerator constants, changing their types to match 5517 // the type of the enum if needed. 5518 for (unsigned i = 0; i != NumElements; ++i) { 5519 EnumConstantDecl *ECD = 5520 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5521 if (!ECD) continue; // Already issued a diagnostic. 5522 5523 // Standard C says the enumerators have int type, but we allow, as an 5524 // extension, the enumerators to be larger than int size. If each 5525 // enumerator value fits in an int, type it as an int, otherwise type it the 5526 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5527 // that X has type 'int', not 'unsigned'. 5528 if (ECD->getType() == Context.IntTy) { 5529 // Make sure the init value is signed. 5530 llvm::APSInt IV = ECD->getInitVal(); 5531 IV.setIsSigned(true); 5532 ECD->setInitVal(IV); 5533 5534 if (getLangOptions().CPlusPlus) 5535 // C++ [dcl.enum]p4: Following the closing brace of an 5536 // enum-specifier, each enumerator has the type of its 5537 // enumeration. 5538 ECD->setType(EnumType); 5539 continue; // Already int type. 5540 } 5541 5542 // Determine whether the value fits into an int. 5543 llvm::APSInt InitVal = ECD->getInitVal(); 5544 bool FitsInInt; 5545 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5546 FitsInInt = InitVal.getActiveBits() < IntWidth; 5547 else 5548 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5549 5550 // If it fits into an integer type, force it. Otherwise force it to match 5551 // the enum decl type. 5552 QualType NewTy; 5553 unsigned NewWidth; 5554 bool NewSign; 5555 if (FitsInInt) { 5556 NewTy = Context.IntTy; 5557 NewWidth = IntWidth; 5558 NewSign = true; 5559 } else if (ECD->getType() == BestType) { 5560 // Already the right type! 5561 if (getLangOptions().CPlusPlus) 5562 // C++ [dcl.enum]p4: Following the closing brace of an 5563 // enum-specifier, each enumerator has the type of its 5564 // enumeration. 5565 ECD->setType(EnumType); 5566 continue; 5567 } else { 5568 NewTy = BestType; 5569 NewWidth = BestWidth; 5570 NewSign = BestType->isSignedIntegerType(); 5571 } 5572 5573 // Adjust the APSInt value. 5574 InitVal.extOrTrunc(NewWidth); 5575 InitVal.setIsSigned(NewSign); 5576 ECD->setInitVal(InitVal); 5577 5578 // Adjust the Expr initializer and type. 5579 if (ECD->getInitExpr()) 5580 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5581 CastExpr::CK_Unknown, 5582 ECD->getInitExpr(), 5583 /*isLvalue=*/false)); 5584 if (getLangOptions().CPlusPlus) 5585 // C++ [dcl.enum]p4: Following the closing brace of an 5586 // enum-specifier, each enumerator has the type of its 5587 // enumeration. 5588 ECD->setType(EnumType); 5589 else 5590 ECD->setType(NewTy); 5591 } 5592 5593 Enum->completeDefinition(Context, BestType); 5594} 5595 5596Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5597 ExprArg expr) { 5598 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5599 5600 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5601 Loc, AsmString); 5602 CurContext->addDecl(New); 5603 return DeclPtrTy::make(New); 5604} 5605 5606void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5607 SourceLocation PragmaLoc, 5608 SourceLocation NameLoc) { 5609 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5610 5611 if (PrevDecl) { 5612 PrevDecl->addAttr(::new (Context) WeakAttr()); 5613 } else { 5614 (void)WeakUndeclaredIdentifiers.insert( 5615 std::pair<IdentifierInfo*,WeakInfo> 5616 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5617 } 5618} 5619 5620void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5621 IdentifierInfo* AliasName, 5622 SourceLocation PragmaLoc, 5623 SourceLocation NameLoc, 5624 SourceLocation AliasNameLoc) { 5625 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5626 WeakInfo W = WeakInfo(Name, NameLoc); 5627 5628 if (PrevDecl) { 5629 if (!PrevDecl->hasAttr<AliasAttr>()) 5630 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5631 DeclApplyPragmaWeak(TUScope, ND, W); 5632 } else { 5633 (void)WeakUndeclaredIdentifiers.insert( 5634 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5635 } 5636} 5637