SemaDecl.cpp revision 54d2596d47cc4ae9067d3b05f533d2176ef8492a
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/Analysis/CFG.h" 19#include "clang/AST/CXXInheritance.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Parse/ParseDiagnostic.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/BitVector.h" 34#include "llvm/ADT/STLExtras.h" 35#include <algorithm> 36#include <cstring> 37#include <functional> 38#include <queue> 39using namespace clang; 40 41/// getDeclName - Return a pretty name for the specified decl if possible, or 42/// an empty string if not. This is used for pretty crash reporting. 43std::string Sema::getDeclName(DeclPtrTy d) { 44 Decl *D = d.getAs<Decl>(); 45 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 46 return DN->getQualifiedNameAsString(); 47 return ""; 48} 49 50Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 51 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 52} 53 54/// \brief If the identifier refers to a type name within this scope, 55/// return the declaration of that type. 56/// 57/// This routine performs ordinary name lookup of the identifier II 58/// within the given scope, with optional C++ scope specifier SS, to 59/// determine whether the name refers to a type. If so, returns an 60/// opaque pointer (actually a QualType) corresponding to that 61/// type. Otherwise, returns NULL. 62/// 63/// If name lookup results in an ambiguity, this routine will complain 64/// and then return NULL. 65Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 66 Scope *S, const CXXScopeSpec *SS, 67 bool isClassName) { 68 // C++ [temp.res]p3: 69 // A qualified-id that refers to a type and in which the 70 // nested-name-specifier depends on a template-parameter (14.6.2) 71 // shall be prefixed by the keyword typename to indicate that the 72 // qualified-id denotes a type, forming an 73 // elaborated-type-specifier (7.1.5.3). 74 // 75 // We therefore do not perform any name lookup if the result would 76 // refer to a member of an unknown specialization. 77 if (SS && isUnknownSpecialization(*SS)) { 78 if (!isClassName) 79 return 0; 80 81 // We know from the grammar that this name refers to a type, so build a 82 // TypenameType node to describe the type. 83 // FIXME: Record somewhere that this TypenameType node has no "typename" 84 // keyword associated with it. 85 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 86 II, SS->getRange()).getAsOpaquePtr(); 87 } 88 89 LookupResult Result; 90 LookupParsedName(Result, S, SS, &II, LookupOrdinaryName, false, false); 91 92 NamedDecl *IIDecl = 0; 93 switch (Result.getKind()) { 94 case LookupResult::NotFound: 95 case LookupResult::FoundOverloaded: 96 return 0; 97 98 case LookupResult::Ambiguous: { 99 // Recover from type-hiding ambiguities by hiding the type. We'll 100 // do the lookup again when looking for an object, and we can 101 // diagnose the error then. If we don't do this, then the error 102 // about hiding the type will be immediately followed by an error 103 // that only makes sense if the identifier was treated like a type. 104 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) 105 return 0; 106 107 // Look to see if we have a type anywhere in the list of results. 108 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 109 Res != ResEnd; ++Res) { 110 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 111 if (!IIDecl || 112 (*Res)->getLocation().getRawEncoding() < 113 IIDecl->getLocation().getRawEncoding()) 114 IIDecl = *Res; 115 } 116 } 117 118 if (!IIDecl) { 119 // None of the entities we found is a type, so there is no way 120 // to even assume that the result is a type. In this case, don't 121 // complain about the ambiguity. The parser will either try to 122 // perform this lookup again (e.g., as an object name), which 123 // will produce the ambiguity, or will complain that it expected 124 // a type name. 125 return 0; 126 } 127 128 // We found a type within the ambiguous lookup; diagnose the 129 // ambiguity and then return that type. This might be the right 130 // answer, or it might not be, but it suppresses any attempt to 131 // perform the name lookup again. 132 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 133 break; 134 } 135 136 case LookupResult::Found: 137 IIDecl = Result.getFoundDecl(); 138 break; 139 } 140 141 if (IIDecl) { 142 QualType T; 143 144 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 145 // Check whether we can use this type 146 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 147 148 if (getLangOptions().CPlusPlus) { 149 // C++ [temp.local]p2: 150 // Within the scope of a class template specialization or 151 // partial specialization, when the injected-class-name is 152 // not followed by a <, it is equivalent to the 153 // injected-class-name followed by the template-argument s 154 // of the class template specialization or partial 155 // specialization enclosed in <>. 156 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 157 if (RD->isInjectedClassName()) 158 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 159 T = Template->getInjectedClassNameType(Context); 160 } 161 162 if (T.isNull()) 163 T = Context.getTypeDeclType(TD); 164 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 165 // Check whether we can use this interface. 166 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 167 168 T = Context.getObjCInterfaceType(IDecl); 169 } else 170 return 0; 171 172 if (SS) 173 T = getQualifiedNameType(*SS, T); 174 175 return T.getAsOpaquePtr(); 176 } 177 178 return 0; 179} 180 181/// isTagName() - This method is called *for error recovery purposes only* 182/// to determine if the specified name is a valid tag name ("struct foo"). If 183/// so, this returns the TST for the tag corresponding to it (TST_enum, 184/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 185/// where the user forgot to specify the tag. 186DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 187 // Do a tag name lookup in this scope. 188 LookupResult R; 189 LookupName(R, S, &II, LookupTagName, false, false); 190 if (R.getKind() == LookupResult::Found) 191 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 192 switch (TD->getTagKind()) { 193 case TagDecl::TK_struct: return DeclSpec::TST_struct; 194 case TagDecl::TK_union: return DeclSpec::TST_union; 195 case TagDecl::TK_class: return DeclSpec::TST_class; 196 case TagDecl::TK_enum: return DeclSpec::TST_enum; 197 } 198 } 199 200 return DeclSpec::TST_unspecified; 201} 202 203bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 204 SourceLocation IILoc, 205 Scope *S, 206 const CXXScopeSpec *SS, 207 TypeTy *&SuggestedType) { 208 // We don't have anything to suggest (yet). 209 SuggestedType = 0; 210 211 // FIXME: Should we move the logic that tries to recover from a missing tag 212 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 213 214 if (!SS) 215 Diag(IILoc, diag::err_unknown_typename) << &II; 216 else if (DeclContext *DC = computeDeclContext(*SS, false)) 217 Diag(IILoc, diag::err_typename_nested_not_found) 218 << &II << DC << SS->getRange(); 219 else if (isDependentScopeSpecifier(*SS)) { 220 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 221 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 222 << SourceRange(SS->getRange().getBegin(), IILoc) 223 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 224 "typename "); 225 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 226 } else { 227 assert(SS && SS->isInvalid() && 228 "Invalid scope specifier has already been diagnosed"); 229 } 230 231 return true; 232} 233 234// Determines the context to return to after temporarily entering a 235// context. This depends in an unnecessarily complicated way on the 236// exact ordering of callbacks from the parser. 237DeclContext *Sema::getContainingDC(DeclContext *DC) { 238 239 // Functions defined inline within classes aren't parsed until we've 240 // finished parsing the top-level class, so the top-level class is 241 // the context we'll need to return to. 242 if (isa<FunctionDecl>(DC)) { 243 DC = DC->getLexicalParent(); 244 245 // A function not defined within a class will always return to its 246 // lexical context. 247 if (!isa<CXXRecordDecl>(DC)) 248 return DC; 249 250 // A C++ inline method/friend is parsed *after* the topmost class 251 // it was declared in is fully parsed ("complete"); the topmost 252 // class is the context we need to return to. 253 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 254 DC = RD; 255 256 // Return the declaration context of the topmost class the inline method is 257 // declared in. 258 return DC; 259 } 260 261 if (isa<ObjCMethodDecl>(DC)) 262 return Context.getTranslationUnitDecl(); 263 264 return DC->getLexicalParent(); 265} 266 267void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 268 assert(getContainingDC(DC) == CurContext && 269 "The next DeclContext should be lexically contained in the current one."); 270 CurContext = DC; 271 S->setEntity(DC); 272} 273 274void Sema::PopDeclContext() { 275 assert(CurContext && "DeclContext imbalance!"); 276 277 CurContext = getContainingDC(CurContext); 278} 279 280/// EnterDeclaratorContext - Used when we must lookup names in the context 281/// of a declarator's nested name specifier. 282void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 283 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 284 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 285 CurContext = DC; 286 assert(CurContext && "No context?"); 287 S->setEntity(CurContext); 288} 289 290void Sema::ExitDeclaratorContext(Scope *S) { 291 S->setEntity(PreDeclaratorDC); 292 PreDeclaratorDC = 0; 293 294 // Reset CurContext to the nearest enclosing context. 295 while (!S->getEntity() && S->getParent()) 296 S = S->getParent(); 297 CurContext = static_cast<DeclContext*>(S->getEntity()); 298 assert(CurContext && "No context?"); 299} 300 301/// \brief Determine whether we allow overloading of the function 302/// PrevDecl with another declaration. 303/// 304/// This routine determines whether overloading is possible, not 305/// whether some new function is actually an overload. It will return 306/// true in C++ (where we can always provide overloads) or, as an 307/// extension, in C when the previous function is already an 308/// overloaded function declaration or has the "overloadable" 309/// attribute. 310static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 311 if (Context.getLangOptions().CPlusPlus) 312 return true; 313 314 if (isa<OverloadedFunctionDecl>(PrevDecl)) 315 return true; 316 317 return PrevDecl->getAttr<OverloadableAttr>() != 0; 318} 319 320/// Add this decl to the scope shadowed decl chains. 321void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 322 // Move up the scope chain until we find the nearest enclosing 323 // non-transparent context. The declaration will be introduced into this 324 // scope. 325 while (S->getEntity() && 326 ((DeclContext *)S->getEntity())->isTransparentContext()) 327 S = S->getParent(); 328 329 // Add scoped declarations into their context, so that they can be 330 // found later. Declarations without a context won't be inserted 331 // into any context. 332 if (AddToContext) 333 CurContext->addDecl(D); 334 335 // Out-of-line function and variable definitions should not be pushed into 336 // scope. 337 if ((isa<FunctionTemplateDecl>(D) && 338 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 339 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 340 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 341 return; 342 343 // If this replaces anything in the current scope, 344 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 345 IEnd = IdResolver.end(); 346 for (; I != IEnd; ++I) { 347 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 348 S->RemoveDecl(DeclPtrTy::make(*I)); 349 IdResolver.RemoveDecl(*I); 350 351 // Should only need to replace one decl. 352 break; 353 } 354 } 355 356 S->AddDecl(DeclPtrTy::make(D)); 357 IdResolver.AddDecl(D); 358} 359 360bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 361 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 362 // Look inside the overload set to determine if any of the declarations 363 // are in scope. (Possibly) build a new overload set containing only 364 // those declarations that are in scope. 365 OverloadedFunctionDecl *NewOvl = 0; 366 bool FoundInScope = false; 367 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 368 FEnd = Ovl->function_end(); 369 F != FEnd; ++F) { 370 NamedDecl *FD = F->get(); 371 if (!isDeclInScope(FD, Ctx, S)) { 372 if (!NewOvl && F != Ovl->function_begin()) { 373 NewOvl = OverloadedFunctionDecl::Create(Context, 374 F->get()->getDeclContext(), 375 F->get()->getDeclName()); 376 D = NewOvl; 377 for (OverloadedFunctionDecl::function_iterator 378 First = Ovl->function_begin(); 379 First != F; ++First) 380 NewOvl->addOverload(*First); 381 } 382 } else { 383 FoundInScope = true; 384 if (NewOvl) 385 NewOvl->addOverload(*F); 386 } 387 } 388 389 return FoundInScope; 390 } 391 392 return IdResolver.isDeclInScope(D, Ctx, Context, S); 393} 394 395void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 396 if (S->decl_empty()) return; 397 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 398 "Scope shouldn't contain decls!"); 399 400 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 401 I != E; ++I) { 402 Decl *TmpD = (*I).getAs<Decl>(); 403 assert(TmpD && "This decl didn't get pushed??"); 404 405 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 406 NamedDecl *D = cast<NamedDecl>(TmpD); 407 408 if (!D->getDeclName()) continue; 409 410 // Diagnose unused variables in this scope. 411 if (!D->isUsed() && !D->hasAttr<UnusedAttr>() && isa<VarDecl>(D) && 412 !isa<ParmVarDecl>(D) && !isa<ImplicitParamDecl>(D) && 413 D->getDeclContext()->isFunctionOrMethod()) 414 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 415 416 // Remove this name from our lexical scope. 417 IdResolver.RemoveDecl(D); 418 } 419} 420 421/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 422/// return 0 if one not found. 423ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 424 // The third "scope" argument is 0 since we aren't enabling lazy built-in 425 // creation from this context. 426 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 427 428 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 429} 430 431/// getNonFieldDeclScope - Retrieves the innermost scope, starting 432/// from S, where a non-field would be declared. This routine copes 433/// with the difference between C and C++ scoping rules in structs and 434/// unions. For example, the following code is well-formed in C but 435/// ill-formed in C++: 436/// @code 437/// struct S6 { 438/// enum { BAR } e; 439/// }; 440/// 441/// void test_S6() { 442/// struct S6 a; 443/// a.e = BAR; 444/// } 445/// @endcode 446/// For the declaration of BAR, this routine will return a different 447/// scope. The scope S will be the scope of the unnamed enumeration 448/// within S6. In C++, this routine will return the scope associated 449/// with S6, because the enumeration's scope is a transparent 450/// context but structures can contain non-field names. In C, this 451/// routine will return the translation unit scope, since the 452/// enumeration's scope is a transparent context and structures cannot 453/// contain non-field names. 454Scope *Sema::getNonFieldDeclScope(Scope *S) { 455 while (((S->getFlags() & Scope::DeclScope) == 0) || 456 (S->getEntity() && 457 ((DeclContext *)S->getEntity())->isTransparentContext()) || 458 (S->isClassScope() && !getLangOptions().CPlusPlus)) 459 S = S->getParent(); 460 return S; 461} 462 463void Sema::InitBuiltinVaListType() { 464 if (!Context.getBuiltinVaListType().isNull()) 465 return; 466 467 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 468 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 469 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 470 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 471} 472 473/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 474/// file scope. lazily create a decl for it. ForRedeclaration is true 475/// if we're creating this built-in in anticipation of redeclaring the 476/// built-in. 477NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 478 Scope *S, bool ForRedeclaration, 479 SourceLocation Loc) { 480 Builtin::ID BID = (Builtin::ID)bid; 481 482 if (Context.BuiltinInfo.hasVAListUse(BID)) 483 InitBuiltinVaListType(); 484 485 ASTContext::GetBuiltinTypeError Error; 486 QualType R = Context.GetBuiltinType(BID, Error); 487 switch (Error) { 488 case ASTContext::GE_None: 489 // Okay 490 break; 491 492 case ASTContext::GE_Missing_stdio: 493 if (ForRedeclaration) 494 Diag(Loc, diag::err_implicit_decl_requires_stdio) 495 << Context.BuiltinInfo.GetName(BID); 496 return 0; 497 498 case ASTContext::GE_Missing_setjmp: 499 if (ForRedeclaration) 500 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 501 << Context.BuiltinInfo.GetName(BID); 502 return 0; 503 } 504 505 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 506 Diag(Loc, diag::ext_implicit_lib_function_decl) 507 << Context.BuiltinInfo.GetName(BID) 508 << R; 509 if (Context.BuiltinInfo.getHeaderName(BID) && 510 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 511 != Diagnostic::Ignored) 512 Diag(Loc, diag::note_please_include_header) 513 << Context.BuiltinInfo.getHeaderName(BID) 514 << Context.BuiltinInfo.GetName(BID); 515 } 516 517 FunctionDecl *New = FunctionDecl::Create(Context, 518 Context.getTranslationUnitDecl(), 519 Loc, II, R, /*DInfo=*/0, 520 FunctionDecl::Extern, false, 521 /*hasPrototype=*/true); 522 New->setImplicit(); 523 524 // Create Decl objects for each parameter, adding them to the 525 // FunctionDecl. 526 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 527 llvm::SmallVector<ParmVarDecl*, 16> Params; 528 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 529 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 530 FT->getArgType(i), /*DInfo=*/0, 531 VarDecl::None, 0)); 532 New->setParams(Context, Params.data(), Params.size()); 533 } 534 535 AddKnownFunctionAttributes(New); 536 537 // TUScope is the translation-unit scope to insert this function into. 538 // FIXME: This is hideous. We need to teach PushOnScopeChains to 539 // relate Scopes to DeclContexts, and probably eliminate CurContext 540 // entirely, but we're not there yet. 541 DeclContext *SavedContext = CurContext; 542 CurContext = Context.getTranslationUnitDecl(); 543 PushOnScopeChains(New, TUScope); 544 CurContext = SavedContext; 545 return New; 546} 547 548/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 549/// same name and scope as a previous declaration 'Old'. Figure out 550/// how to resolve this situation, merging decls or emitting 551/// diagnostics as appropriate. If there was an error, set New to be invalid. 552/// 553void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 554 // If either decl is known invalid already, set the new one to be invalid and 555 // don't bother doing any merging checks. 556 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 557 return New->setInvalidDecl(); 558 559 // Allow multiple definitions for ObjC built-in typedefs. 560 // FIXME: Verify the underlying types are equivalent! 561 if (getLangOptions().ObjC1) { 562 const IdentifierInfo *TypeID = New->getIdentifier(); 563 switch (TypeID->getLength()) { 564 default: break; 565 case 2: 566 if (!TypeID->isStr("id")) 567 break; 568 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 569 // Install the built-in type for 'id', ignoring the current definition. 570 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 571 return; 572 case 5: 573 if (!TypeID->isStr("Class")) 574 break; 575 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 576 // Install the built-in type for 'Class', ignoring the current definition. 577 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 578 return; 579 case 3: 580 if (!TypeID->isStr("SEL")) 581 break; 582 Context.setObjCSelType(Context.getTypeDeclType(New)); 583 return; 584 case 8: 585 if (!TypeID->isStr("Protocol")) 586 break; 587 Context.setObjCProtoType(New->getUnderlyingType()); 588 return; 589 } 590 // Fall through - the typedef name was not a builtin type. 591 } 592 // Verify the old decl was also a type. 593 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 594 if (!Old) { 595 Diag(New->getLocation(), diag::err_redefinition_different_kind) 596 << New->getDeclName(); 597 if (OldD->getLocation().isValid()) 598 Diag(OldD->getLocation(), diag::note_previous_definition); 599 return New->setInvalidDecl(); 600 } 601 602 // Determine the "old" type we'll use for checking and diagnostics. 603 QualType OldType; 604 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 605 OldType = OldTypedef->getUnderlyingType(); 606 else 607 OldType = Context.getTypeDeclType(Old); 608 609 // If the typedef types are not identical, reject them in all languages and 610 // with any extensions enabled. 611 612 if (OldType != New->getUnderlyingType() && 613 Context.getCanonicalType(OldType) != 614 Context.getCanonicalType(New->getUnderlyingType())) { 615 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 616 << New->getUnderlyingType() << OldType; 617 if (Old->getLocation().isValid()) 618 Diag(Old->getLocation(), diag::note_previous_definition); 619 return New->setInvalidDecl(); 620 } 621 622 if (getLangOptions().Microsoft) 623 return; 624 625 // C++ [dcl.typedef]p2: 626 // In a given non-class scope, a typedef specifier can be used to 627 // redefine the name of any type declared in that scope to refer 628 // to the type to which it already refers. 629 if (getLangOptions().CPlusPlus) { 630 if (!isa<CXXRecordDecl>(CurContext)) 631 return; 632 Diag(New->getLocation(), diag::err_redefinition) 633 << New->getDeclName(); 634 Diag(Old->getLocation(), diag::note_previous_definition); 635 return New->setInvalidDecl(); 636 } 637 638 // If we have a redefinition of a typedef in C, emit a warning. This warning 639 // is normally mapped to an error, but can be controlled with 640 // -Wtypedef-redefinition. If either the original or the redefinition is 641 // in a system header, don't emit this for compatibility with GCC. 642 if (PP.getDiagnostics().getSuppressSystemWarnings() && 643 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 644 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 645 return; 646 647 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 648 << New->getDeclName(); 649 Diag(Old->getLocation(), diag::note_previous_definition); 650 return; 651} 652 653/// DeclhasAttr - returns true if decl Declaration already has the target 654/// attribute. 655static bool 656DeclHasAttr(const Decl *decl, const Attr *target) { 657 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 658 if (attr->getKind() == target->getKind()) 659 return true; 660 661 return false; 662} 663 664/// MergeAttributes - append attributes from the Old decl to the New one. 665static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 666 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 667 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 668 Attr *NewAttr = attr->clone(C); 669 NewAttr->setInherited(true); 670 New->addAttr(NewAttr); 671 } 672 } 673} 674 675/// Used in MergeFunctionDecl to keep track of function parameters in 676/// C. 677struct GNUCompatibleParamWarning { 678 ParmVarDecl *OldParm; 679 ParmVarDecl *NewParm; 680 QualType PromotedType; 681}; 682 683/// MergeFunctionDecl - We just parsed a function 'New' from 684/// declarator D which has the same name and scope as a previous 685/// declaration 'Old'. Figure out how to resolve this situation, 686/// merging decls or emitting diagnostics as appropriate. 687/// 688/// In C++, New and Old must be declarations that are not 689/// overloaded. Use IsOverload to determine whether New and Old are 690/// overloaded, and to select the Old declaration that New should be 691/// merged with. 692/// 693/// Returns true if there was an error, false otherwise. 694bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 695 assert(!isa<OverloadedFunctionDecl>(OldD) && 696 "Cannot merge with an overloaded function declaration"); 697 698 // Verify the old decl was also a function. 699 FunctionDecl *Old = 0; 700 if (FunctionTemplateDecl *OldFunctionTemplate 701 = dyn_cast<FunctionTemplateDecl>(OldD)) 702 Old = OldFunctionTemplate->getTemplatedDecl(); 703 else 704 Old = dyn_cast<FunctionDecl>(OldD); 705 if (!Old) { 706 Diag(New->getLocation(), diag::err_redefinition_different_kind) 707 << New->getDeclName(); 708 Diag(OldD->getLocation(), diag::note_previous_definition); 709 return true; 710 } 711 712 // Determine whether the previous declaration was a definition, 713 // implicit declaration, or a declaration. 714 diag::kind PrevDiag; 715 if (Old->isThisDeclarationADefinition()) 716 PrevDiag = diag::note_previous_definition; 717 else if (Old->isImplicit()) 718 PrevDiag = diag::note_previous_implicit_declaration; 719 else 720 PrevDiag = diag::note_previous_declaration; 721 722 QualType OldQType = Context.getCanonicalType(Old->getType()); 723 QualType NewQType = Context.getCanonicalType(New->getType()); 724 725 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 726 New->getStorageClass() == FunctionDecl::Static && 727 Old->getStorageClass() != FunctionDecl::Static) { 728 Diag(New->getLocation(), diag::err_static_non_static) 729 << New; 730 Diag(Old->getLocation(), PrevDiag); 731 return true; 732 } 733 734 if (getLangOptions().CPlusPlus) { 735 // (C++98 13.1p2): 736 // Certain function declarations cannot be overloaded: 737 // -- Function declarations that differ only in the return type 738 // cannot be overloaded. 739 QualType OldReturnType 740 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 741 QualType NewReturnType 742 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 743 if (OldReturnType != NewReturnType) { 744 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 745 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 746 return true; 747 } 748 749 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 750 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 751 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 752 NewMethod->getLexicalDeclContext()->isRecord()) { 753 // -- Member function declarations with the same name and the 754 // same parameter types cannot be overloaded if any of them 755 // is a static member function declaration. 756 if (OldMethod->isStatic() || NewMethod->isStatic()) { 757 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 758 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 759 return true; 760 } 761 762 // C++ [class.mem]p1: 763 // [...] A member shall not be declared twice in the 764 // member-specification, except that a nested class or member 765 // class template can be declared and then later defined. 766 unsigned NewDiag; 767 if (isa<CXXConstructorDecl>(OldMethod)) 768 NewDiag = diag::err_constructor_redeclared; 769 else if (isa<CXXDestructorDecl>(NewMethod)) 770 NewDiag = diag::err_destructor_redeclared; 771 else if (isa<CXXConversionDecl>(NewMethod)) 772 NewDiag = diag::err_conv_function_redeclared; 773 else 774 NewDiag = diag::err_member_redeclared; 775 776 Diag(New->getLocation(), NewDiag); 777 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 778 } 779 780 // (C++98 8.3.5p3): 781 // All declarations for a function shall agree exactly in both the 782 // return type and the parameter-type-list. 783 if (OldQType == NewQType) 784 return MergeCompatibleFunctionDecls(New, Old); 785 786 // Fall through for conflicting redeclarations and redefinitions. 787 } 788 789 // C: Function types need to be compatible, not identical. This handles 790 // duplicate function decls like "void f(int); void f(enum X);" properly. 791 if (!getLangOptions().CPlusPlus && 792 Context.typesAreCompatible(OldQType, NewQType)) { 793 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 794 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 795 const FunctionProtoType *OldProto = 0; 796 if (isa<FunctionNoProtoType>(NewFuncType) && 797 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 798 // The old declaration provided a function prototype, but the 799 // new declaration does not. Merge in the prototype. 800 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 801 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 802 OldProto->arg_type_end()); 803 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 804 ParamTypes.data(), ParamTypes.size(), 805 OldProto->isVariadic(), 806 OldProto->getTypeQuals()); 807 New->setType(NewQType); 808 New->setHasInheritedPrototype(); 809 810 // Synthesize a parameter for each argument type. 811 llvm::SmallVector<ParmVarDecl*, 16> Params; 812 for (FunctionProtoType::arg_type_iterator 813 ParamType = OldProto->arg_type_begin(), 814 ParamEnd = OldProto->arg_type_end(); 815 ParamType != ParamEnd; ++ParamType) { 816 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 817 SourceLocation(), 0, 818 *ParamType, /*DInfo=*/0, 819 VarDecl::None, 0); 820 Param->setImplicit(); 821 Params.push_back(Param); 822 } 823 824 New->setParams(Context, Params.data(), Params.size()); 825 } 826 827 return MergeCompatibleFunctionDecls(New, Old); 828 } 829 830 // GNU C permits a K&R definition to follow a prototype declaration 831 // if the declared types of the parameters in the K&R definition 832 // match the types in the prototype declaration, even when the 833 // promoted types of the parameters from the K&R definition differ 834 // from the types in the prototype. GCC then keeps the types from 835 // the prototype. 836 // 837 // If a variadic prototype is followed by a non-variadic K&R definition, 838 // the K&R definition becomes variadic. This is sort of an edge case, but 839 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 840 // C99 6.9.1p8. 841 if (!getLangOptions().CPlusPlus && 842 Old->hasPrototype() && !New->hasPrototype() && 843 New->getType()->getAs<FunctionProtoType>() && 844 Old->getNumParams() == New->getNumParams()) { 845 llvm::SmallVector<QualType, 16> ArgTypes; 846 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 847 const FunctionProtoType *OldProto 848 = Old->getType()->getAs<FunctionProtoType>(); 849 const FunctionProtoType *NewProto 850 = New->getType()->getAs<FunctionProtoType>(); 851 852 // Determine whether this is the GNU C extension. 853 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 854 NewProto->getResultType()); 855 bool LooseCompatible = !MergedReturn.isNull(); 856 for (unsigned Idx = 0, End = Old->getNumParams(); 857 LooseCompatible && Idx != End; ++Idx) { 858 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 859 ParmVarDecl *NewParm = New->getParamDecl(Idx); 860 if (Context.typesAreCompatible(OldParm->getType(), 861 NewProto->getArgType(Idx))) { 862 ArgTypes.push_back(NewParm->getType()); 863 } else if (Context.typesAreCompatible(OldParm->getType(), 864 NewParm->getType())) { 865 GNUCompatibleParamWarning Warn 866 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 867 Warnings.push_back(Warn); 868 ArgTypes.push_back(NewParm->getType()); 869 } else 870 LooseCompatible = false; 871 } 872 873 if (LooseCompatible) { 874 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 875 Diag(Warnings[Warn].NewParm->getLocation(), 876 diag::ext_param_promoted_not_compatible_with_prototype) 877 << Warnings[Warn].PromotedType 878 << Warnings[Warn].OldParm->getType(); 879 Diag(Warnings[Warn].OldParm->getLocation(), 880 diag::note_previous_declaration); 881 } 882 883 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 884 ArgTypes.size(), 885 OldProto->isVariadic(), 0)); 886 return MergeCompatibleFunctionDecls(New, Old); 887 } 888 889 // Fall through to diagnose conflicting types. 890 } 891 892 // A function that has already been declared has been redeclared or defined 893 // with a different type- show appropriate diagnostic 894 if (unsigned BuiltinID = Old->getBuiltinID()) { 895 // The user has declared a builtin function with an incompatible 896 // signature. 897 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 898 // The function the user is redeclaring is a library-defined 899 // function like 'malloc' or 'printf'. Warn about the 900 // redeclaration, then pretend that we don't know about this 901 // library built-in. 902 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 903 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 904 << Old << Old->getType(); 905 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 906 Old->setInvalidDecl(); 907 return false; 908 } 909 910 PrevDiag = diag::note_previous_builtin_declaration; 911 } 912 913 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 914 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 915 return true; 916} 917 918/// \brief Completes the merge of two function declarations that are 919/// known to be compatible. 920/// 921/// This routine handles the merging of attributes and other 922/// properties of function declarations form the old declaration to 923/// the new declaration, once we know that New is in fact a 924/// redeclaration of Old. 925/// 926/// \returns false 927bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 928 // Merge the attributes 929 MergeAttributes(New, Old, Context); 930 931 // Merge the storage class. 932 if (Old->getStorageClass() != FunctionDecl::Extern && 933 Old->getStorageClass() != FunctionDecl::None) 934 New->setStorageClass(Old->getStorageClass()); 935 936 // Merge "pure" flag. 937 if (Old->isPure()) 938 New->setPure(); 939 940 // Merge the "deleted" flag. 941 if (Old->isDeleted()) 942 New->setDeleted(); 943 944 if (getLangOptions().CPlusPlus) 945 return MergeCXXFunctionDecl(New, Old); 946 947 return false; 948} 949 950/// MergeVarDecl - We just parsed a variable 'New' which has the same name 951/// and scope as a previous declaration 'Old'. Figure out how to resolve this 952/// situation, merging decls or emitting diagnostics as appropriate. 953/// 954/// Tentative definition rules (C99 6.9.2p2) are checked by 955/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 956/// definitions here, since the initializer hasn't been attached. 957/// 958void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 959 // If either decl is invalid, make sure the new one is marked invalid and 960 // don't do any other checking. 961 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 962 return New->setInvalidDecl(); 963 964 // Verify the old decl was also a variable. 965 VarDecl *Old = dyn_cast<VarDecl>(OldD); 966 if (!Old) { 967 Diag(New->getLocation(), diag::err_redefinition_different_kind) 968 << New->getDeclName(); 969 Diag(OldD->getLocation(), diag::note_previous_definition); 970 return New->setInvalidDecl(); 971 } 972 973 MergeAttributes(New, Old, Context); 974 975 // Merge the types 976 QualType MergedT; 977 if (getLangOptions().CPlusPlus) { 978 if (Context.hasSameType(New->getType(), Old->getType())) 979 MergedT = New->getType(); 980 // C++ [basic.types]p7: 981 // [...] The declared type of an array object might be an array of 982 // unknown size and therefore be incomplete at one point in a 983 // translation unit and complete later on; [...] 984 else if (Old->getType()->isIncompleteArrayType() && 985 New->getType()->isArrayType()) { 986 CanQual<ArrayType> OldArray 987 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 988 CanQual<ArrayType> NewArray 989 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 990 if (OldArray->getElementType() == NewArray->getElementType()) 991 MergedT = New->getType(); 992 } 993 } else { 994 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 995 } 996 if (MergedT.isNull()) { 997 Diag(New->getLocation(), diag::err_redefinition_different_type) 998 << New->getDeclName(); 999 Diag(Old->getLocation(), diag::note_previous_definition); 1000 return New->setInvalidDecl(); 1001 } 1002 New->setType(MergedT); 1003 1004 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1005 if (New->getStorageClass() == VarDecl::Static && 1006 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1007 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1008 Diag(Old->getLocation(), diag::note_previous_definition); 1009 return New->setInvalidDecl(); 1010 } 1011 // C99 6.2.2p4: 1012 // For an identifier declared with the storage-class specifier 1013 // extern in a scope in which a prior declaration of that 1014 // identifier is visible,23) if the prior declaration specifies 1015 // internal or external linkage, the linkage of the identifier at 1016 // the later declaration is the same as the linkage specified at 1017 // the prior declaration. If no prior declaration is visible, or 1018 // if the prior declaration specifies no linkage, then the 1019 // identifier has external linkage. 1020 if (New->hasExternalStorage() && Old->hasLinkage()) 1021 /* Okay */; 1022 else if (New->getStorageClass() != VarDecl::Static && 1023 Old->getStorageClass() == VarDecl::Static) { 1024 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1025 Diag(Old->getLocation(), diag::note_previous_definition); 1026 return New->setInvalidDecl(); 1027 } 1028 1029 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1030 1031 // FIXME: The test for external storage here seems wrong? We still 1032 // need to check for mismatches. 1033 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1034 // Don't complain about out-of-line definitions of static members. 1035 !(Old->getLexicalDeclContext()->isRecord() && 1036 !New->getLexicalDeclContext()->isRecord())) { 1037 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1038 Diag(Old->getLocation(), diag::note_previous_definition); 1039 return New->setInvalidDecl(); 1040 } 1041 1042 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1043 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1044 Diag(Old->getLocation(), diag::note_previous_definition); 1045 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1046 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1047 Diag(Old->getLocation(), diag::note_previous_definition); 1048 } 1049 1050 // Keep a chain of previous declarations. 1051 New->setPreviousDeclaration(Old); 1052} 1053 1054/// CheckFallThrough - Check that we don't fall off the end of a 1055/// Statement that should return a value. 1056/// 1057/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1058/// MaybeFallThrough iff we might or might not fall off the end and 1059/// NeverFallThrough iff we never fall off the end of the statement. We assume 1060/// that functions not marked noreturn will return. 1061Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1062 // FIXME: Eventually share this CFG object when we have other warnings based 1063 // of the CFG. This can be done using AnalysisContext. 1064 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1065 1066 // FIXME: They should never return 0, fix that, delete this code. 1067 if (cfg == 0) 1068 return NeverFallThrough; 1069 // The CFG leaves in dead things, and we don't want to dead code paths to 1070 // confuse us, so we mark all live things first. 1071 std::queue<CFGBlock*> workq; 1072 llvm::BitVector live(cfg->getNumBlockIDs()); 1073 // Prep work queue 1074 workq.push(&cfg->getEntry()); 1075 // Solve 1076 while (!workq.empty()) { 1077 CFGBlock *item = workq.front(); 1078 workq.pop(); 1079 live.set(item->getBlockID()); 1080 for (CFGBlock::succ_iterator I=item->succ_begin(), 1081 E=item->succ_end(); 1082 I != E; 1083 ++I) { 1084 if ((*I) && !live[(*I)->getBlockID()]) { 1085 live.set((*I)->getBlockID()); 1086 workq.push(*I); 1087 } 1088 } 1089 } 1090 1091 // Now we know what is live, we check the live precessors of the exit block 1092 // and look for fall through paths, being careful to ignore normal returns, 1093 // and exceptional paths. 1094 bool HasLiveReturn = false; 1095 bool HasFakeEdge = false; 1096 bool HasPlainEdge = false; 1097 for (CFGBlock::succ_iterator I=cfg->getExit().pred_begin(), 1098 E = cfg->getExit().pred_end(); 1099 I != E; 1100 ++I) { 1101 CFGBlock& B = **I; 1102 if (!live[B.getBlockID()]) 1103 continue; 1104 if (B.size() == 0) { 1105 // A labeled empty statement, or the entry block... 1106 HasPlainEdge = true; 1107 continue; 1108 } 1109 Stmt *S = B[B.size()-1]; 1110 if (isa<ReturnStmt>(S)) { 1111 HasLiveReturn = true; 1112 continue; 1113 } 1114 if (isa<ObjCAtThrowStmt>(S)) { 1115 HasFakeEdge = true; 1116 continue; 1117 } 1118 if (isa<CXXThrowExpr>(S)) { 1119 HasFakeEdge = true; 1120 continue; 1121 } 1122 bool NoReturnEdge = false; 1123 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1124 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1125 if (CEE->getType().getNoReturnAttr()) { 1126 NoReturnEdge = true; 1127 HasFakeEdge = true; 1128 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1129 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1130 if (FD->hasAttr<NoReturnAttr>()) { 1131 NoReturnEdge = true; 1132 HasFakeEdge = true; 1133 } 1134 } 1135 } 1136 } 1137 // FIXME: Add noreturn message sends. 1138 if (NoReturnEdge == false) 1139 HasPlainEdge = true; 1140 } 1141 if (!HasPlainEdge) 1142 return NeverFallThrough; 1143 if (HasFakeEdge || HasLiveReturn) 1144 return MaybeFallThrough; 1145 // This says AlwaysFallThrough for calls to functions that are not marked 1146 // noreturn, that don't return. If people would like this warning to be more 1147 // accurate, such functions should be marked as noreturn. 1148 return AlwaysFallThrough; 1149} 1150 1151/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1152/// function that should return a value. Check that we don't fall off the end 1153/// of a noreturn function. We assume that functions and blocks not marked 1154/// noreturn will return. 1155void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1156 // FIXME: Would be nice if we had a better way to control cascading errors, 1157 // but for now, avoid them. The problem is that when Parse sees: 1158 // int foo() { return a; } 1159 // The return is eaten and the Sema code sees just: 1160 // int foo() { } 1161 // which this code would then warn about. 1162 if (getDiagnostics().hasErrorOccurred()) 1163 return; 1164 bool ReturnsVoid = false; 1165 bool HasNoReturn = false; 1166 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1167 // If the result type of the function is a dependent type, we don't know 1168 // whether it will be void or not, so don't 1169 if (FD->getResultType()->isDependentType()) 1170 return; 1171 if (FD->getResultType()->isVoidType()) 1172 ReturnsVoid = true; 1173 if (FD->hasAttr<NoReturnAttr>()) 1174 HasNoReturn = true; 1175 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1176 if (MD->getResultType()->isVoidType()) 1177 ReturnsVoid = true; 1178 if (MD->hasAttr<NoReturnAttr>()) 1179 HasNoReturn = true; 1180 } 1181 1182 // Short circuit for compilation speed. 1183 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1184 == Diagnostic::Ignored || ReturnsVoid) 1185 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1186 == Diagnostic::Ignored || !HasNoReturn) 1187 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1188 == Diagnostic::Ignored || !ReturnsVoid)) 1189 return; 1190 // FIXME: Function try block 1191 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1192 switch (CheckFallThrough(Body)) { 1193 case MaybeFallThrough: 1194 if (HasNoReturn) 1195 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1196 else if (!ReturnsVoid) 1197 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1198 break; 1199 case AlwaysFallThrough: 1200 if (HasNoReturn) 1201 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1202 else if (!ReturnsVoid) 1203 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1204 break; 1205 case NeverFallThrough: 1206 if (ReturnsVoid) 1207 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1208 break; 1209 } 1210 } 1211} 1212 1213/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1214/// that should return a value. Check that we don't fall off the end of a 1215/// noreturn block. We assume that functions and blocks not marked noreturn 1216/// will return. 1217void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1218 // FIXME: Would be nice if we had a better way to control cascading errors, 1219 // but for now, avoid them. The problem is that when Parse sees: 1220 // int foo() { return a; } 1221 // The return is eaten and the Sema code sees just: 1222 // int foo() { } 1223 // which this code would then warn about. 1224 if (getDiagnostics().hasErrorOccurred()) 1225 return; 1226 bool ReturnsVoid = false; 1227 bool HasNoReturn = false; 1228 if (const FunctionType *FT = BlockTy->getPointeeType()->getAs<FunctionType>()) { 1229 if (FT->getResultType()->isVoidType()) 1230 ReturnsVoid = true; 1231 if (FT->getNoReturnAttr()) 1232 HasNoReturn = true; 1233 } 1234 1235 // Short circuit for compilation speed. 1236 if (ReturnsVoid 1237 && !HasNoReturn 1238 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1239 == Diagnostic::Ignored || !ReturnsVoid)) 1240 return; 1241 // FIXME: Funtion try block 1242 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1243 switch (CheckFallThrough(Body)) { 1244 case MaybeFallThrough: 1245 if (HasNoReturn) 1246 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1247 else if (!ReturnsVoid) 1248 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1249 break; 1250 case AlwaysFallThrough: 1251 if (HasNoReturn) 1252 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1253 else if (!ReturnsVoid) 1254 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1255 break; 1256 case NeverFallThrough: 1257 if (ReturnsVoid) 1258 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1259 break; 1260 } 1261 } 1262} 1263 1264/// CheckParmsForFunctionDef - Check that the parameters of the given 1265/// function are appropriate for the definition of a function. This 1266/// takes care of any checks that cannot be performed on the 1267/// declaration itself, e.g., that the types of each of the function 1268/// parameters are complete. 1269bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1270 bool HasInvalidParm = false; 1271 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1272 ParmVarDecl *Param = FD->getParamDecl(p); 1273 1274 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1275 // function declarator that is part of a function definition of 1276 // that function shall not have incomplete type. 1277 // 1278 // This is also C++ [dcl.fct]p6. 1279 if (!Param->isInvalidDecl() && 1280 RequireCompleteType(Param->getLocation(), Param->getType(), 1281 diag::err_typecheck_decl_incomplete_type)) { 1282 Param->setInvalidDecl(); 1283 HasInvalidParm = true; 1284 } 1285 1286 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1287 // declaration of each parameter shall include an identifier. 1288 if (Param->getIdentifier() == 0 && 1289 !Param->isImplicit() && 1290 !getLangOptions().CPlusPlus) 1291 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1292 } 1293 1294 return HasInvalidParm; 1295} 1296 1297/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1298/// no declarator (e.g. "struct foo;") is parsed. 1299Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1300 // FIXME: Error on auto/register at file scope 1301 // FIXME: Error on inline/virtual/explicit 1302 // FIXME: Error on invalid restrict 1303 // FIXME: Warn on useless __thread 1304 // FIXME: Warn on useless const/volatile 1305 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1306 // FIXME: Warn on useless attributes 1307 Decl *TagD = 0; 1308 TagDecl *Tag = 0; 1309 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1310 DS.getTypeSpecType() == DeclSpec::TST_struct || 1311 DS.getTypeSpecType() == DeclSpec::TST_union || 1312 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1313 TagD = static_cast<Decl *>(DS.getTypeRep()); 1314 1315 if (!TagD) // We probably had an error 1316 return DeclPtrTy(); 1317 1318 // Note that the above type specs guarantee that the 1319 // type rep is a Decl, whereas in many of the others 1320 // it's a Type. 1321 Tag = dyn_cast<TagDecl>(TagD); 1322 } 1323 1324 if (DS.isFriendSpecified()) { 1325 // If we're dealing with a class template decl, assume that the 1326 // template routines are handling it. 1327 if (TagD && isa<ClassTemplateDecl>(TagD)) 1328 return DeclPtrTy(); 1329 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1330 } 1331 1332 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1333 if (!Record->getDeclName() && Record->isDefinition() && 1334 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1335 if (getLangOptions().CPlusPlus || 1336 Record->getDeclContext()->isRecord()) 1337 return BuildAnonymousStructOrUnion(S, DS, Record); 1338 1339 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1340 << DS.getSourceRange(); 1341 } 1342 1343 // Microsoft allows unnamed struct/union fields. Don't complain 1344 // about them. 1345 // FIXME: Should we support Microsoft's extensions in this area? 1346 if (Record->getDeclName() && getLangOptions().Microsoft) 1347 return DeclPtrTy::make(Tag); 1348 } 1349 1350 if (!DS.isMissingDeclaratorOk() && 1351 DS.getTypeSpecType() != DeclSpec::TST_error) { 1352 // Warn about typedefs of enums without names, since this is an 1353 // extension in both Microsoft an GNU. 1354 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1355 Tag && isa<EnumDecl>(Tag)) { 1356 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1357 << DS.getSourceRange(); 1358 return DeclPtrTy::make(Tag); 1359 } 1360 1361 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1362 << DS.getSourceRange(); 1363 return DeclPtrTy(); 1364 } 1365 1366 return DeclPtrTy::make(Tag); 1367} 1368 1369/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1370/// anonymous struct or union AnonRecord into the owning context Owner 1371/// and scope S. This routine will be invoked just after we realize 1372/// that an unnamed union or struct is actually an anonymous union or 1373/// struct, e.g., 1374/// 1375/// @code 1376/// union { 1377/// int i; 1378/// float f; 1379/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1380/// // f into the surrounding scope.x 1381/// @endcode 1382/// 1383/// This routine is recursive, injecting the names of nested anonymous 1384/// structs/unions into the owning context and scope as well. 1385bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1386 RecordDecl *AnonRecord) { 1387 bool Invalid = false; 1388 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1389 FEnd = AnonRecord->field_end(); 1390 F != FEnd; ++F) { 1391 if ((*F)->getDeclName()) { 1392 LookupResult R; 1393 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1394 LookupOrdinaryName, true); 1395 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1396 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1397 // C++ [class.union]p2: 1398 // The names of the members of an anonymous union shall be 1399 // distinct from the names of any other entity in the 1400 // scope in which the anonymous union is declared. 1401 unsigned diagKind 1402 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1403 : diag::err_anonymous_struct_member_redecl; 1404 Diag((*F)->getLocation(), diagKind) 1405 << (*F)->getDeclName(); 1406 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1407 Invalid = true; 1408 } else { 1409 // C++ [class.union]p2: 1410 // For the purpose of name lookup, after the anonymous union 1411 // definition, the members of the anonymous union are 1412 // considered to have been defined in the scope in which the 1413 // anonymous union is declared. 1414 Owner->makeDeclVisibleInContext(*F); 1415 S->AddDecl(DeclPtrTy::make(*F)); 1416 IdResolver.AddDecl(*F); 1417 } 1418 } else if (const RecordType *InnerRecordType 1419 = (*F)->getType()->getAs<RecordType>()) { 1420 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1421 if (InnerRecord->isAnonymousStructOrUnion()) 1422 Invalid = Invalid || 1423 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1424 } 1425 } 1426 1427 return Invalid; 1428} 1429 1430/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1431/// anonymous structure or union. Anonymous unions are a C++ feature 1432/// (C++ [class.union]) and a GNU C extension; anonymous structures 1433/// are a GNU C and GNU C++ extension. 1434Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1435 RecordDecl *Record) { 1436 DeclContext *Owner = Record->getDeclContext(); 1437 1438 // Diagnose whether this anonymous struct/union is an extension. 1439 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1440 Diag(Record->getLocation(), diag::ext_anonymous_union); 1441 else if (!Record->isUnion()) 1442 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1443 1444 // C and C++ require different kinds of checks for anonymous 1445 // structs/unions. 1446 bool Invalid = false; 1447 if (getLangOptions().CPlusPlus) { 1448 const char* PrevSpec = 0; 1449 unsigned DiagID; 1450 // C++ [class.union]p3: 1451 // Anonymous unions declared in a named namespace or in the 1452 // global namespace shall be declared static. 1453 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1454 (isa<TranslationUnitDecl>(Owner) || 1455 (isa<NamespaceDecl>(Owner) && 1456 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1457 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1458 Invalid = true; 1459 1460 // Recover by adding 'static'. 1461 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1462 PrevSpec, DiagID); 1463 } 1464 // C++ [class.union]p3: 1465 // A storage class is not allowed in a declaration of an 1466 // anonymous union in a class scope. 1467 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1468 isa<RecordDecl>(Owner)) { 1469 Diag(DS.getStorageClassSpecLoc(), 1470 diag::err_anonymous_union_with_storage_spec); 1471 Invalid = true; 1472 1473 // Recover by removing the storage specifier. 1474 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1475 PrevSpec, DiagID); 1476 } 1477 1478 // C++ [class.union]p2: 1479 // The member-specification of an anonymous union shall only 1480 // define non-static data members. [Note: nested types and 1481 // functions cannot be declared within an anonymous union. ] 1482 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1483 MemEnd = Record->decls_end(); 1484 Mem != MemEnd; ++Mem) { 1485 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1486 // C++ [class.union]p3: 1487 // An anonymous union shall not have private or protected 1488 // members (clause 11). 1489 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1490 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1491 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1492 Invalid = true; 1493 } 1494 } else if ((*Mem)->isImplicit()) { 1495 // Any implicit members are fine. 1496 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1497 // This is a type that showed up in an 1498 // elaborated-type-specifier inside the anonymous struct or 1499 // union, but which actually declares a type outside of the 1500 // anonymous struct or union. It's okay. 1501 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1502 if (!MemRecord->isAnonymousStructOrUnion() && 1503 MemRecord->getDeclName()) { 1504 // This is a nested type declaration. 1505 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1506 << (int)Record->isUnion(); 1507 Invalid = true; 1508 } 1509 } else { 1510 // We have something that isn't a non-static data 1511 // member. Complain about it. 1512 unsigned DK = diag::err_anonymous_record_bad_member; 1513 if (isa<TypeDecl>(*Mem)) 1514 DK = diag::err_anonymous_record_with_type; 1515 else if (isa<FunctionDecl>(*Mem)) 1516 DK = diag::err_anonymous_record_with_function; 1517 else if (isa<VarDecl>(*Mem)) 1518 DK = diag::err_anonymous_record_with_static; 1519 Diag((*Mem)->getLocation(), DK) 1520 << (int)Record->isUnion(); 1521 Invalid = true; 1522 } 1523 } 1524 } 1525 1526 if (!Record->isUnion() && !Owner->isRecord()) { 1527 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1528 << (int)getLangOptions().CPlusPlus; 1529 Invalid = true; 1530 } 1531 1532 // Mock up a declarator. 1533 Declarator Dc(DS, Declarator::TypeNameContext); 1534 DeclaratorInfo *DInfo = 0; 1535 GetTypeForDeclarator(Dc, S, &DInfo); 1536 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1537 1538 // Create a declaration for this anonymous struct/union. 1539 NamedDecl *Anon = 0; 1540 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1541 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1542 /*IdentifierInfo=*/0, 1543 Context.getTypeDeclType(Record), 1544 DInfo, 1545 /*BitWidth=*/0, /*Mutable=*/false); 1546 Anon->setAccess(AS_public); 1547 if (getLangOptions().CPlusPlus) 1548 FieldCollector->Add(cast<FieldDecl>(Anon)); 1549 } else { 1550 VarDecl::StorageClass SC; 1551 switch (DS.getStorageClassSpec()) { 1552 default: assert(0 && "Unknown storage class!"); 1553 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1554 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1555 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1556 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1557 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1558 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1559 case DeclSpec::SCS_mutable: 1560 // mutable can only appear on non-static class members, so it's always 1561 // an error here 1562 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1563 Invalid = true; 1564 SC = VarDecl::None; 1565 break; 1566 } 1567 1568 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1569 /*IdentifierInfo=*/0, 1570 Context.getTypeDeclType(Record), 1571 DInfo, 1572 SC); 1573 } 1574 Anon->setImplicit(); 1575 1576 // Add the anonymous struct/union object to the current 1577 // context. We'll be referencing this object when we refer to one of 1578 // its members. 1579 Owner->addDecl(Anon); 1580 1581 // Inject the members of the anonymous struct/union into the owning 1582 // context and into the identifier resolver chain for name lookup 1583 // purposes. 1584 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1585 Invalid = true; 1586 1587 // Mark this as an anonymous struct/union type. Note that we do not 1588 // do this until after we have already checked and injected the 1589 // members of this anonymous struct/union type, because otherwise 1590 // the members could be injected twice: once by DeclContext when it 1591 // builds its lookup table, and once by 1592 // InjectAnonymousStructOrUnionMembers. 1593 Record->setAnonymousStructOrUnion(true); 1594 1595 if (Invalid) 1596 Anon->setInvalidDecl(); 1597 1598 return DeclPtrTy::make(Anon); 1599} 1600 1601 1602/// GetNameForDeclarator - Determine the full declaration name for the 1603/// given Declarator. 1604DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1605 switch (D.getKind()) { 1606 case Declarator::DK_Abstract: 1607 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1608 return DeclarationName(); 1609 1610 case Declarator::DK_Normal: 1611 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1612 return DeclarationName(D.getIdentifier()); 1613 1614 case Declarator::DK_Constructor: { 1615 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1616 return Context.DeclarationNames.getCXXConstructorName( 1617 Context.getCanonicalType(Ty)); 1618 } 1619 1620 case Declarator::DK_Destructor: { 1621 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1622 return Context.DeclarationNames.getCXXDestructorName( 1623 Context.getCanonicalType(Ty)); 1624 } 1625 1626 case Declarator::DK_Conversion: { 1627 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1628 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1629 return Context.DeclarationNames.getCXXConversionFunctionName( 1630 Context.getCanonicalType(Ty)); 1631 } 1632 1633 case Declarator::DK_Operator: 1634 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1635 return Context.DeclarationNames.getCXXOperatorName( 1636 D.getOverloadedOperator()); 1637 1638 case Declarator::DK_TemplateId: { 1639 TemplateName Name 1640 = TemplateName::getFromVoidPointer(D.getTemplateId()->Template); 1641 if (TemplateDecl *Template = Name.getAsTemplateDecl()) 1642 return Template->getDeclName(); 1643 if (OverloadedFunctionDecl *Ovl = Name.getAsOverloadedFunctionDecl()) 1644 return Ovl->getDeclName(); 1645 1646 return DeclarationName(); 1647 } 1648 } 1649 1650 assert(false && "Unknown name kind"); 1651 return DeclarationName(); 1652} 1653 1654/// isNearlyMatchingFunction - Determine whether the C++ functions 1655/// Declaration and Definition are "nearly" matching. This heuristic 1656/// is used to improve diagnostics in the case where an out-of-line 1657/// function definition doesn't match any declaration within 1658/// the class or namespace. 1659static bool isNearlyMatchingFunction(ASTContext &Context, 1660 FunctionDecl *Declaration, 1661 FunctionDecl *Definition) { 1662 if (Declaration->param_size() != Definition->param_size()) 1663 return false; 1664 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1665 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1666 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1667 1668 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1669 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1670 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1671 return false; 1672 } 1673 1674 return true; 1675} 1676 1677Sema::DeclPtrTy 1678Sema::HandleDeclarator(Scope *S, Declarator &D, 1679 MultiTemplateParamsArg TemplateParamLists, 1680 bool IsFunctionDefinition) { 1681 DeclarationName Name = GetNameForDeclarator(D); 1682 1683 // All of these full declarators require an identifier. If it doesn't have 1684 // one, the ParsedFreeStandingDeclSpec action should be used. 1685 if (!Name) { 1686 if (!D.isInvalidType()) // Reject this if we think it is valid. 1687 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1688 diag::err_declarator_need_ident) 1689 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1690 return DeclPtrTy(); 1691 } 1692 1693 // The scope passed in may not be a decl scope. Zip up the scope tree until 1694 // we find one that is. 1695 while ((S->getFlags() & Scope::DeclScope) == 0 || 1696 (S->getFlags() & Scope::TemplateParamScope) != 0) 1697 S = S->getParent(); 1698 1699 // If this is an out-of-line definition of a member of a class template 1700 // or class template partial specialization, we may need to rebuild the 1701 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1702 // for more information. 1703 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1704 // handle expressions properly. 1705 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1706 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1707 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1708 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1709 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1710 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1711 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1712 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1713 // FIXME: Preserve type source info. 1714 QualType T = GetTypeFromParser(DS.getTypeRep()); 1715 EnterDeclaratorContext(S, DC); 1716 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1717 ExitDeclaratorContext(S); 1718 if (T.isNull()) 1719 return DeclPtrTy(); 1720 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1721 } 1722 } 1723 1724 DeclContext *DC; 1725 NamedDecl *PrevDecl; 1726 NamedDecl *New; 1727 1728 DeclaratorInfo *DInfo = 0; 1729 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1730 1731 // See if this is a redefinition of a variable in the same scope. 1732 if (D.getCXXScopeSpec().isInvalid()) { 1733 DC = CurContext; 1734 PrevDecl = 0; 1735 D.setInvalidType(); 1736 } else if (!D.getCXXScopeSpec().isSet()) { 1737 LookupNameKind NameKind = LookupOrdinaryName; 1738 1739 // If the declaration we're planning to build will be a function 1740 // or object with linkage, then look for another declaration with 1741 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1742 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1743 /* Do nothing*/; 1744 else if (R->isFunctionType()) { 1745 if (CurContext->isFunctionOrMethod() || 1746 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1747 NameKind = LookupRedeclarationWithLinkage; 1748 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1749 NameKind = LookupRedeclarationWithLinkage; 1750 else if (CurContext->getLookupContext()->isTranslationUnit() && 1751 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1752 NameKind = LookupRedeclarationWithLinkage; 1753 1754 DC = CurContext; 1755 LookupResult R; 1756 LookupName(R, S, Name, NameKind, true, 1757 NameKind == LookupRedeclarationWithLinkage, 1758 D.getIdentifierLoc()); 1759 PrevDecl = R.getAsSingleDecl(Context); 1760 } else { // Something like "int foo::x;" 1761 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1762 1763 if (!DC) { 1764 // If we could not compute the declaration context, it's because the 1765 // declaration context is dependent but does not refer to a class, 1766 // class template, or class template partial specialization. Complain 1767 // and return early, to avoid the coming semantic disaster. 1768 Diag(D.getIdentifierLoc(), 1769 diag::err_template_qualified_declarator_no_match) 1770 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1771 << D.getCXXScopeSpec().getRange(); 1772 return DeclPtrTy(); 1773 } 1774 1775 if (!DC->isDependentContext() && 1776 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1777 return DeclPtrTy(); 1778 1779 LookupResult Res; 1780 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1781 PrevDecl = Res.getAsSingleDecl(Context); 1782 1783 // C++ 7.3.1.2p2: 1784 // Members (including explicit specializations of templates) of a named 1785 // namespace can also be defined outside that namespace by explicit 1786 // qualification of the name being defined, provided that the entity being 1787 // defined was already declared in the namespace and the definition appears 1788 // after the point of declaration in a namespace that encloses the 1789 // declarations namespace. 1790 // 1791 // Note that we only check the context at this point. We don't yet 1792 // have enough information to make sure that PrevDecl is actually 1793 // the declaration we want to match. For example, given: 1794 // 1795 // class X { 1796 // void f(); 1797 // void f(float); 1798 // }; 1799 // 1800 // void X::f(int) { } // ill-formed 1801 // 1802 // In this case, PrevDecl will point to the overload set 1803 // containing the two f's declared in X, but neither of them 1804 // matches. 1805 1806 // First check whether we named the global scope. 1807 if (isa<TranslationUnitDecl>(DC)) { 1808 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1809 << Name << D.getCXXScopeSpec().getRange(); 1810 } else if (!CurContext->Encloses(DC)) { 1811 // The qualifying scope doesn't enclose the original declaration. 1812 // Emit diagnostic based on current scope. 1813 SourceLocation L = D.getIdentifierLoc(); 1814 SourceRange R = D.getCXXScopeSpec().getRange(); 1815 if (isa<FunctionDecl>(CurContext)) 1816 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1817 else 1818 Diag(L, diag::err_invalid_declarator_scope) 1819 << Name << cast<NamedDecl>(DC) << R; 1820 D.setInvalidType(); 1821 } 1822 } 1823 1824 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1825 // Maybe we will complain about the shadowed template parameter. 1826 if (!D.isInvalidType()) 1827 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1828 D.setInvalidType(); 1829 1830 // Just pretend that we didn't see the previous declaration. 1831 PrevDecl = 0; 1832 } 1833 1834 // In C++, the previous declaration we find might be a tag type 1835 // (class or enum). In this case, the new declaration will hide the 1836 // tag type. Note that this does does not apply if we're declaring a 1837 // typedef (C++ [dcl.typedef]p4). 1838 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1839 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1840 PrevDecl = 0; 1841 1842 bool Redeclaration = false; 1843 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1844 if (TemplateParamLists.size()) { 1845 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1846 return DeclPtrTy(); 1847 } 1848 1849 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1850 } else if (R->isFunctionType()) { 1851 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1852 move(TemplateParamLists), 1853 IsFunctionDefinition, Redeclaration); 1854 } else { 1855 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1856 move(TemplateParamLists), 1857 Redeclaration); 1858 } 1859 1860 if (New == 0) 1861 return DeclPtrTy(); 1862 1863 // If this has an identifier and is not an invalid redeclaration or 1864 // function template specialization, add it to the scope stack. 1865 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1866 !(isa<FunctionDecl>(New) && 1867 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1868 PushOnScopeChains(New, S); 1869 1870 return DeclPtrTy::make(New); 1871} 1872 1873/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1874/// types into constant array types in certain situations which would otherwise 1875/// be errors (for GCC compatibility). 1876static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1877 ASTContext &Context, 1878 bool &SizeIsNegative) { 1879 // This method tries to turn a variable array into a constant 1880 // array even when the size isn't an ICE. This is necessary 1881 // for compatibility with code that depends on gcc's buggy 1882 // constant expression folding, like struct {char x[(int)(char*)2];} 1883 SizeIsNegative = false; 1884 1885 QualifierCollector Qs; 1886 const Type *Ty = Qs.strip(T); 1887 1888 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1889 QualType Pointee = PTy->getPointeeType(); 1890 QualType FixedType = 1891 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1892 if (FixedType.isNull()) return FixedType; 1893 FixedType = Context.getPointerType(FixedType); 1894 return Qs.apply(FixedType); 1895 } 1896 1897 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1898 if (!VLATy) 1899 return QualType(); 1900 // FIXME: We should probably handle this case 1901 if (VLATy->getElementType()->isVariablyModifiedType()) 1902 return QualType(); 1903 1904 Expr::EvalResult EvalResult; 1905 if (!VLATy->getSizeExpr() || 1906 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1907 !EvalResult.Val.isInt()) 1908 return QualType(); 1909 1910 llvm::APSInt &Res = EvalResult.Val.getInt(); 1911 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1912 // TODO: preserve the size expression in declarator info 1913 return Context.getConstantArrayType(VLATy->getElementType(), 1914 Res, ArrayType::Normal, 0); 1915 } 1916 1917 SizeIsNegative = true; 1918 return QualType(); 1919} 1920 1921/// \brief Register the given locally-scoped external C declaration so 1922/// that it can be found later for redeclarations 1923void 1924Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1925 Scope *S) { 1926 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1927 "Decl is not a locally-scoped decl!"); 1928 // Note that we have a locally-scoped external with this name. 1929 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1930 1931 if (!PrevDecl) 1932 return; 1933 1934 // If there was a previous declaration of this variable, it may be 1935 // in our identifier chain. Update the identifier chain with the new 1936 // declaration. 1937 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1938 // The previous declaration was found on the identifer resolver 1939 // chain, so remove it from its scope. 1940 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1941 S = S->getParent(); 1942 1943 if (S) 1944 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1945 } 1946} 1947 1948/// \brief Diagnose function specifiers on a declaration of an identifier that 1949/// does not identify a function. 1950void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1951 // FIXME: We should probably indicate the identifier in question to avoid 1952 // confusion for constructs like "inline int a(), b;" 1953 if (D.getDeclSpec().isInlineSpecified()) 1954 Diag(D.getDeclSpec().getInlineSpecLoc(), 1955 diag::err_inline_non_function); 1956 1957 if (D.getDeclSpec().isVirtualSpecified()) 1958 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1959 diag::err_virtual_non_function); 1960 1961 if (D.getDeclSpec().isExplicitSpecified()) 1962 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1963 diag::err_explicit_non_function); 1964} 1965 1966NamedDecl* 1967Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1968 QualType R, DeclaratorInfo *DInfo, 1969 NamedDecl* PrevDecl, bool &Redeclaration) { 1970 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1971 if (D.getCXXScopeSpec().isSet()) { 1972 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1973 << D.getCXXScopeSpec().getRange(); 1974 D.setInvalidType(); 1975 // Pretend we didn't see the scope specifier. 1976 DC = 0; 1977 } 1978 1979 if (getLangOptions().CPlusPlus) { 1980 // Check that there are no default arguments (C++ only). 1981 CheckExtraCXXDefaultArguments(D); 1982 } 1983 1984 DiagnoseFunctionSpecifiers(D); 1985 1986 if (D.getDeclSpec().isThreadSpecified()) 1987 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1988 1989 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1990 if (!NewTD) return 0; 1991 1992 if (D.isInvalidType()) 1993 NewTD->setInvalidDecl(); 1994 1995 // Handle attributes prior to checking for duplicates in MergeVarDecl 1996 ProcessDeclAttributes(S, NewTD, D); 1997 // Merge the decl with the existing one if appropriate. If the decl is 1998 // in an outer scope, it isn't the same thing. 1999 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2000 Redeclaration = true; 2001 MergeTypeDefDecl(NewTD, PrevDecl); 2002 } 2003 2004 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2005 // then it shall have block scope. 2006 QualType T = NewTD->getUnderlyingType(); 2007 if (T->isVariablyModifiedType()) { 2008 CurFunctionNeedsScopeChecking = true; 2009 2010 if (S->getFnParent() == 0) { 2011 bool SizeIsNegative; 2012 QualType FixedTy = 2013 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2014 if (!FixedTy.isNull()) { 2015 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2016 NewTD->setUnderlyingType(FixedTy); 2017 } else { 2018 if (SizeIsNegative) 2019 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2020 else if (T->isVariableArrayType()) 2021 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2022 else 2023 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2024 NewTD->setInvalidDecl(); 2025 } 2026 } 2027 } 2028 2029 // If this is the C FILE type, notify the AST context. 2030 if (IdentifierInfo *II = NewTD->getIdentifier()) 2031 if (!NewTD->isInvalidDecl() && 2032 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2033 if (II->isStr("FILE")) 2034 Context.setFILEDecl(NewTD); 2035 else if (II->isStr("jmp_buf")) 2036 Context.setjmp_bufDecl(NewTD); 2037 else if (II->isStr("sigjmp_buf")) 2038 Context.setsigjmp_bufDecl(NewTD); 2039 } 2040 2041 return NewTD; 2042} 2043 2044/// \brief Determines whether the given declaration is an out-of-scope 2045/// previous declaration. 2046/// 2047/// This routine should be invoked when name lookup has found a 2048/// previous declaration (PrevDecl) that is not in the scope where a 2049/// new declaration by the same name is being introduced. If the new 2050/// declaration occurs in a local scope, previous declarations with 2051/// linkage may still be considered previous declarations (C99 2052/// 6.2.2p4-5, C++ [basic.link]p6). 2053/// 2054/// \param PrevDecl the previous declaration found by name 2055/// lookup 2056/// 2057/// \param DC the context in which the new declaration is being 2058/// declared. 2059/// 2060/// \returns true if PrevDecl is an out-of-scope previous declaration 2061/// for a new delcaration with the same name. 2062static bool 2063isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2064 ASTContext &Context) { 2065 if (!PrevDecl) 2066 return 0; 2067 2068 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2069 // case we need to check each of the overloaded functions. 2070 if (!PrevDecl->hasLinkage()) 2071 return false; 2072 2073 if (Context.getLangOptions().CPlusPlus) { 2074 // C++ [basic.link]p6: 2075 // If there is a visible declaration of an entity with linkage 2076 // having the same name and type, ignoring entities declared 2077 // outside the innermost enclosing namespace scope, the block 2078 // scope declaration declares that same entity and receives the 2079 // linkage of the previous declaration. 2080 DeclContext *OuterContext = DC->getLookupContext(); 2081 if (!OuterContext->isFunctionOrMethod()) 2082 // This rule only applies to block-scope declarations. 2083 return false; 2084 else { 2085 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2086 if (PrevOuterContext->isRecord()) 2087 // We found a member function: ignore it. 2088 return false; 2089 else { 2090 // Find the innermost enclosing namespace for the new and 2091 // previous declarations. 2092 while (!OuterContext->isFileContext()) 2093 OuterContext = OuterContext->getParent(); 2094 while (!PrevOuterContext->isFileContext()) 2095 PrevOuterContext = PrevOuterContext->getParent(); 2096 2097 // The previous declaration is in a different namespace, so it 2098 // isn't the same function. 2099 if (OuterContext->getPrimaryContext() != 2100 PrevOuterContext->getPrimaryContext()) 2101 return false; 2102 } 2103 } 2104 } 2105 2106 return true; 2107} 2108 2109NamedDecl* 2110Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2111 QualType R, DeclaratorInfo *DInfo, 2112 NamedDecl* PrevDecl, 2113 MultiTemplateParamsArg TemplateParamLists, 2114 bool &Redeclaration) { 2115 DeclarationName Name = GetNameForDeclarator(D); 2116 2117 // Check that there are no default arguments (C++ only). 2118 if (getLangOptions().CPlusPlus) 2119 CheckExtraCXXDefaultArguments(D); 2120 2121 VarDecl *NewVD; 2122 VarDecl::StorageClass SC; 2123 switch (D.getDeclSpec().getStorageClassSpec()) { 2124 default: assert(0 && "Unknown storage class!"); 2125 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2126 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2127 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2128 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2129 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2130 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2131 case DeclSpec::SCS_mutable: 2132 // mutable can only appear on non-static class members, so it's always 2133 // an error here 2134 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2135 D.setInvalidType(); 2136 SC = VarDecl::None; 2137 break; 2138 } 2139 2140 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2141 if (!II) { 2142 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2143 << Name.getAsString(); 2144 return 0; 2145 } 2146 2147 DiagnoseFunctionSpecifiers(D); 2148 2149 if (!DC->isRecord() && S->getFnParent() == 0) { 2150 // C99 6.9p2: The storage-class specifiers auto and register shall not 2151 // appear in the declaration specifiers in an external declaration. 2152 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2153 2154 // If this is a register variable with an asm label specified, then this 2155 // is a GNU extension. 2156 if (SC == VarDecl::Register && D.getAsmLabel()) 2157 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2158 else 2159 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2160 D.setInvalidType(); 2161 } 2162 } 2163 if (DC->isRecord() && !CurContext->isRecord()) { 2164 // This is an out-of-line definition of a static data member. 2165 if (SC == VarDecl::Static) { 2166 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2167 diag::err_static_out_of_line) 2168 << CodeModificationHint::CreateRemoval( 2169 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2170 } else if (SC == VarDecl::None) 2171 SC = VarDecl::Static; 2172 } 2173 if (SC == VarDecl::Static) { 2174 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2175 if (RD->isLocalClass()) 2176 Diag(D.getIdentifierLoc(), 2177 diag::err_static_data_member_not_allowed_in_local_class) 2178 << Name << RD->getDeclName(); 2179 } 2180 } 2181 2182 // Match up the template parameter lists with the scope specifier, then 2183 // determine whether we have a template or a template specialization. 2184 bool isExplicitSpecialization = false; 2185 if (TemplateParameterList *TemplateParams 2186 = MatchTemplateParametersToScopeSpecifier( 2187 D.getDeclSpec().getSourceRange().getBegin(), 2188 D.getCXXScopeSpec(), 2189 (TemplateParameterList**)TemplateParamLists.get(), 2190 TemplateParamLists.size(), 2191 isExplicitSpecialization)) { 2192 if (TemplateParams->size() > 0) { 2193 // There is no such thing as a variable template. 2194 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2195 << II 2196 << SourceRange(TemplateParams->getTemplateLoc(), 2197 TemplateParams->getRAngleLoc()); 2198 return 0; 2199 } else { 2200 // There is an extraneous 'template<>' for this variable. Complain 2201 // about it, but allow the declaration of the variable. 2202 Diag(TemplateParams->getTemplateLoc(), 2203 diag::err_template_variable_noparams) 2204 << II 2205 << SourceRange(TemplateParams->getTemplateLoc(), 2206 TemplateParams->getRAngleLoc()); 2207 2208 isExplicitSpecialization = true; 2209 } 2210 } 2211 2212 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2213 II, R, DInfo, SC); 2214 2215 if (D.isInvalidType()) 2216 NewVD->setInvalidDecl(); 2217 2218 if (D.getDeclSpec().isThreadSpecified()) { 2219 if (NewVD->hasLocalStorage()) 2220 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2221 else if (!Context.Target.isTLSSupported()) 2222 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2223 else 2224 NewVD->setThreadSpecified(true); 2225 } 2226 2227 // Set the lexical context. If the declarator has a C++ scope specifier, the 2228 // lexical context will be different from the semantic context. 2229 NewVD->setLexicalDeclContext(CurContext); 2230 2231 // Handle attributes prior to checking for duplicates in MergeVarDecl 2232 ProcessDeclAttributes(S, NewVD, D); 2233 2234 // Handle GNU asm-label extension (encoded as an attribute). 2235 if (Expr *E = (Expr*) D.getAsmLabel()) { 2236 // The parser guarantees this is a string. 2237 StringLiteral *SE = cast<StringLiteral>(E); 2238 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2239 SE->getByteLength()))); 2240 } 2241 2242 // If name lookup finds a previous declaration that is not in the 2243 // same scope as the new declaration, this may still be an 2244 // acceptable redeclaration. 2245 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2246 !(NewVD->hasLinkage() && 2247 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2248 PrevDecl = 0; 2249 2250 // Merge the decl with the existing one if appropriate. 2251 if (PrevDecl) { 2252 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2253 // The user tried to define a non-static data member 2254 // out-of-line (C++ [dcl.meaning]p1). 2255 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2256 << D.getCXXScopeSpec().getRange(); 2257 PrevDecl = 0; 2258 NewVD->setInvalidDecl(); 2259 } 2260 } else if (D.getCXXScopeSpec().isSet()) { 2261 // No previous declaration in the qualifying scope. 2262 Diag(D.getIdentifierLoc(), diag::err_no_member) 2263 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2264 << D.getCXXScopeSpec().getRange(); 2265 NewVD->setInvalidDecl(); 2266 } 2267 2268 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2269 2270 // This is an explicit specialization of a static data member. Check it. 2271 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2272 CheckMemberSpecialization(NewVD, PrevDecl)) 2273 NewVD->setInvalidDecl(); 2274 2275 // attributes declared post-definition are currently ignored 2276 if (PrevDecl) { 2277 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2278 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2279 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2280 Diag(Def->getLocation(), diag::note_previous_definition); 2281 } 2282 } 2283 2284 // If this is a locally-scoped extern C variable, update the map of 2285 // such variables. 2286 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2287 !NewVD->isInvalidDecl()) 2288 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2289 2290 return NewVD; 2291} 2292 2293/// \brief Perform semantic checking on a newly-created variable 2294/// declaration. 2295/// 2296/// This routine performs all of the type-checking required for a 2297/// variable declaration once it has been built. It is used both to 2298/// check variables after they have been parsed and their declarators 2299/// have been translated into a declaration, and to check variables 2300/// that have been instantiated from a template. 2301/// 2302/// Sets NewVD->isInvalidDecl() if an error was encountered. 2303void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2304 bool &Redeclaration) { 2305 // If the decl is already known invalid, don't check it. 2306 if (NewVD->isInvalidDecl()) 2307 return; 2308 2309 QualType T = NewVD->getType(); 2310 2311 if (T->isObjCInterfaceType()) { 2312 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2313 return NewVD->setInvalidDecl(); 2314 } 2315 2316 // The variable can not have an abstract class type. 2317 if (RequireNonAbstractType(NewVD->getLocation(), T, 2318 diag::err_abstract_type_in_decl, 2319 AbstractVariableType)) 2320 return NewVD->setInvalidDecl(); 2321 2322 // Emit an error if an address space was applied to decl with local storage. 2323 // This includes arrays of objects with address space qualifiers, but not 2324 // automatic variables that point to other address spaces. 2325 // ISO/IEC TR 18037 S5.1.2 2326 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2327 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2328 return NewVD->setInvalidDecl(); 2329 } 2330 2331 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2332 && !NewVD->hasAttr<BlocksAttr>()) 2333 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2334 2335 bool isVM = T->isVariablyModifiedType(); 2336 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2337 NewVD->hasAttr<BlocksAttr>()) 2338 CurFunctionNeedsScopeChecking = true; 2339 2340 if ((isVM && NewVD->hasLinkage()) || 2341 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2342 bool SizeIsNegative; 2343 QualType FixedTy = 2344 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2345 2346 if (FixedTy.isNull() && T->isVariableArrayType()) { 2347 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2348 // FIXME: This won't give the correct result for 2349 // int a[10][n]; 2350 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2351 2352 if (NewVD->isFileVarDecl()) 2353 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2354 << SizeRange; 2355 else if (NewVD->getStorageClass() == VarDecl::Static) 2356 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2357 << SizeRange; 2358 else 2359 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2360 << SizeRange; 2361 return NewVD->setInvalidDecl(); 2362 } 2363 2364 if (FixedTy.isNull()) { 2365 if (NewVD->isFileVarDecl()) 2366 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2367 else 2368 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2369 return NewVD->setInvalidDecl(); 2370 } 2371 2372 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2373 NewVD->setType(FixedTy); 2374 } 2375 2376 if (!PrevDecl && NewVD->isExternC()) { 2377 // Since we did not find anything by this name and we're declaring 2378 // an extern "C" variable, look for a non-visible extern "C" 2379 // declaration with the same name. 2380 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2381 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2382 if (Pos != LocallyScopedExternalDecls.end()) 2383 PrevDecl = Pos->second; 2384 } 2385 2386 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2387 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2388 << T; 2389 return NewVD->setInvalidDecl(); 2390 } 2391 2392 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2393 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2394 return NewVD->setInvalidDecl(); 2395 } 2396 2397 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2398 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2399 return NewVD->setInvalidDecl(); 2400 } 2401 2402 if (PrevDecl) { 2403 Redeclaration = true; 2404 MergeVarDecl(NewVD, PrevDecl); 2405 } 2406} 2407 2408static bool isUsingDecl(Decl *D) { 2409 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2410} 2411 2412/// \brief Data used with FindOverriddenMethod 2413struct FindOverriddenMethodData { 2414 Sema *S; 2415 CXXMethodDecl *Method; 2416}; 2417 2418/// \brief Member lookup function that determines whether a given C++ 2419/// method overrides a method in a base class, to be used with 2420/// CXXRecordDecl::lookupInBases(). 2421static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2422 CXXBasePath &Path, 2423 void *UserData) { 2424 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2425 2426 FindOverriddenMethodData *Data 2427 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2428 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2429 Path.Decls.first != Path.Decls.second; 2430 ++Path.Decls.first) { 2431 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2432 OverloadedFunctionDecl::function_iterator MatchedDecl; 2433 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2434 return true; 2435 } 2436 } 2437 2438 return false; 2439} 2440 2441NamedDecl* 2442Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2443 QualType R, DeclaratorInfo *DInfo, 2444 NamedDecl* PrevDecl, 2445 MultiTemplateParamsArg TemplateParamLists, 2446 bool IsFunctionDefinition, bool &Redeclaration) { 2447 assert(R.getTypePtr()->isFunctionType()); 2448 2449 DeclarationName Name = GetNameForDeclarator(D); 2450 FunctionDecl::StorageClass SC = FunctionDecl::None; 2451 switch (D.getDeclSpec().getStorageClassSpec()) { 2452 default: assert(0 && "Unknown storage class!"); 2453 case DeclSpec::SCS_auto: 2454 case DeclSpec::SCS_register: 2455 case DeclSpec::SCS_mutable: 2456 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2457 diag::err_typecheck_sclass_func); 2458 D.setInvalidType(); 2459 break; 2460 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2461 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2462 case DeclSpec::SCS_static: { 2463 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2464 // C99 6.7.1p5: 2465 // The declaration of an identifier for a function that has 2466 // block scope shall have no explicit storage-class specifier 2467 // other than extern 2468 // See also (C++ [dcl.stc]p4). 2469 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2470 diag::err_static_block_func); 2471 SC = FunctionDecl::None; 2472 } else 2473 SC = FunctionDecl::Static; 2474 break; 2475 } 2476 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2477 } 2478 2479 if (D.getDeclSpec().isThreadSpecified()) 2480 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2481 2482 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2483 bool isInline = D.getDeclSpec().isInlineSpecified(); 2484 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2485 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2486 2487 // Check that the return type is not an abstract class type. 2488 // For record types, this is done by the AbstractClassUsageDiagnoser once 2489 // the class has been completely parsed. 2490 if (!DC->isRecord() && 2491 RequireNonAbstractType(D.getIdentifierLoc(), 2492 R->getAs<FunctionType>()->getResultType(), 2493 diag::err_abstract_type_in_decl, 2494 AbstractReturnType)) 2495 D.setInvalidType(); 2496 2497 // Do not allow returning a objc interface by-value. 2498 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2499 Diag(D.getIdentifierLoc(), 2500 diag::err_object_cannot_be_passed_returned_by_value) << 0 2501 << R->getAs<FunctionType>()->getResultType(); 2502 D.setInvalidType(); 2503 } 2504 2505 bool isVirtualOkay = false; 2506 FunctionDecl *NewFD; 2507 2508 if (isFriend) { 2509 // DC is the namespace in which the function is being declared. 2510 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2511 "friend function being created in a non-namespace context"); 2512 2513 // C++ [class.friend]p5 2514 // A function can be defined in a friend declaration of a 2515 // class . . . . Such a function is implicitly inline. 2516 isInline |= IsFunctionDefinition; 2517 } 2518 2519 if (D.getKind() == Declarator::DK_Constructor) { 2520 // This is a C++ constructor declaration. 2521 assert(DC->isRecord() && 2522 "Constructors can only be declared in a member context"); 2523 2524 R = CheckConstructorDeclarator(D, R, SC); 2525 2526 // Create the new declaration 2527 NewFD = CXXConstructorDecl::Create(Context, 2528 cast<CXXRecordDecl>(DC), 2529 D.getIdentifierLoc(), Name, R, DInfo, 2530 isExplicit, isInline, 2531 /*isImplicitlyDeclared=*/false); 2532 } else if (D.getKind() == Declarator::DK_Destructor) { 2533 // This is a C++ destructor declaration. 2534 if (DC->isRecord()) { 2535 R = CheckDestructorDeclarator(D, SC); 2536 2537 NewFD = CXXDestructorDecl::Create(Context, 2538 cast<CXXRecordDecl>(DC), 2539 D.getIdentifierLoc(), Name, R, 2540 isInline, 2541 /*isImplicitlyDeclared=*/false); 2542 2543 isVirtualOkay = true; 2544 } else { 2545 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2546 2547 // Create a FunctionDecl to satisfy the function definition parsing 2548 // code path. 2549 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2550 Name, R, DInfo, SC, isInline, 2551 /*hasPrototype=*/true); 2552 D.setInvalidType(); 2553 } 2554 } else if (D.getKind() == Declarator::DK_Conversion) { 2555 if (!DC->isRecord()) { 2556 Diag(D.getIdentifierLoc(), 2557 diag::err_conv_function_not_member); 2558 return 0; 2559 } 2560 2561 CheckConversionDeclarator(D, R, SC); 2562 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2563 D.getIdentifierLoc(), Name, R, DInfo, 2564 isInline, isExplicit); 2565 2566 isVirtualOkay = true; 2567 } else if (DC->isRecord()) { 2568 // If the of the function is the same as the name of the record, then this 2569 // must be an invalid constructor that has a return type. 2570 // (The parser checks for a return type and makes the declarator a 2571 // constructor if it has no return type). 2572 // must have an invalid constructor that has a return type 2573 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2574 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2575 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2576 << SourceRange(D.getIdentifierLoc()); 2577 return 0; 2578 } 2579 2580 // This is a C++ method declaration. 2581 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2582 D.getIdentifierLoc(), Name, R, DInfo, 2583 (SC == FunctionDecl::Static), isInline); 2584 2585 isVirtualOkay = (SC != FunctionDecl::Static); 2586 } else { 2587 // Determine whether the function was written with a 2588 // prototype. This true when: 2589 // - we're in C++ (where every function has a prototype), 2590 // - there is a prototype in the declarator, or 2591 // - the type R of the function is some kind of typedef or other reference 2592 // to a type name (which eventually refers to a function type). 2593 bool HasPrototype = 2594 getLangOptions().CPlusPlus || 2595 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2596 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2597 2598 NewFD = FunctionDecl::Create(Context, DC, 2599 D.getIdentifierLoc(), 2600 Name, R, DInfo, SC, isInline, HasPrototype); 2601 } 2602 2603 if (D.isInvalidType()) 2604 NewFD->setInvalidDecl(); 2605 2606 // Set the lexical context. If the declarator has a C++ 2607 // scope specifier, or is the object of a friend declaration, the 2608 // lexical context will be different from the semantic context. 2609 NewFD->setLexicalDeclContext(CurContext); 2610 2611 // Match up the template parameter lists with the scope specifier, then 2612 // determine whether we have a template or a template specialization. 2613 FunctionTemplateDecl *FunctionTemplate = 0; 2614 bool isExplicitSpecialization = false; 2615 bool isFunctionTemplateSpecialization = false; 2616 if (TemplateParameterList *TemplateParams 2617 = MatchTemplateParametersToScopeSpecifier( 2618 D.getDeclSpec().getSourceRange().getBegin(), 2619 D.getCXXScopeSpec(), 2620 (TemplateParameterList**)TemplateParamLists.get(), 2621 TemplateParamLists.size(), 2622 isExplicitSpecialization)) { 2623 if (TemplateParams->size() > 0) { 2624 // This is a function template 2625 2626 // Check that we can declare a template here. 2627 if (CheckTemplateDeclScope(S, TemplateParams)) 2628 return 0; 2629 2630 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2631 NewFD->getLocation(), 2632 Name, TemplateParams, 2633 NewFD); 2634 FunctionTemplate->setLexicalDeclContext(CurContext); 2635 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2636 } else { 2637 // This is a function template specialization. 2638 isFunctionTemplateSpecialization = true; 2639 } 2640 2641 // FIXME: Free this memory properly. 2642 TemplateParamLists.release(); 2643 } 2644 2645 // C++ [dcl.fct.spec]p5: 2646 // The virtual specifier shall only be used in declarations of 2647 // nonstatic class member functions that appear within a 2648 // member-specification of a class declaration; see 10.3. 2649 // 2650 if (isVirtual && !NewFD->isInvalidDecl()) { 2651 if (!isVirtualOkay) { 2652 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2653 diag::err_virtual_non_function); 2654 } else if (!CurContext->isRecord()) { 2655 // 'virtual' was specified outside of the class. 2656 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2657 << CodeModificationHint::CreateRemoval( 2658 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2659 } else { 2660 // Okay: Add virtual to the method. 2661 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2662 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2663 CurClass->setAggregate(false); 2664 CurClass->setPOD(false); 2665 CurClass->setEmpty(false); 2666 CurClass->setPolymorphic(true); 2667 CurClass->setHasTrivialConstructor(false); 2668 CurClass->setHasTrivialCopyConstructor(false); 2669 CurClass->setHasTrivialCopyAssignment(false); 2670 } 2671 } 2672 2673 if (isFriend) { 2674 if (FunctionTemplate) { 2675 FunctionTemplate->setObjectOfFriendDecl( 2676 /* PreviouslyDeclared= */ PrevDecl != NULL); 2677 FunctionTemplate->setAccess(AS_public); 2678 } 2679 else 2680 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2681 2682 NewFD->setAccess(AS_public); 2683 } 2684 2685 2686 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2687 // Look for virtual methods in base classes that this method might override. 2688 CXXBasePaths Paths; 2689 FindOverriddenMethodData Data; 2690 Data.Method = NewMD; 2691 Data.S = this; 2692 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2693 Paths)) { 2694 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2695 E = Paths.found_decls_end(); I != E; ++I) { 2696 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2697 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2698 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2699 NewMD->addOverriddenMethod(OldMD); 2700 } 2701 } 2702 } 2703 } 2704 2705 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2706 !CurContext->isRecord()) { 2707 // C++ [class.static]p1: 2708 // A data or function member of a class may be declared static 2709 // in a class definition, in which case it is a static member of 2710 // the class. 2711 2712 // Complain about the 'static' specifier if it's on an out-of-line 2713 // member function definition. 2714 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2715 diag::err_static_out_of_line) 2716 << CodeModificationHint::CreateRemoval( 2717 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2718 } 2719 2720 // Handle GNU asm-label extension (encoded as an attribute). 2721 if (Expr *E = (Expr*) D.getAsmLabel()) { 2722 // The parser guarantees this is a string. 2723 StringLiteral *SE = cast<StringLiteral>(E); 2724 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2725 SE->getByteLength()))); 2726 } 2727 2728 // Copy the parameter declarations from the declarator D to the function 2729 // declaration NewFD, if they are available. First scavenge them into Params. 2730 llvm::SmallVector<ParmVarDecl*, 16> Params; 2731 if (D.getNumTypeObjects() > 0) { 2732 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2733 2734 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2735 // function that takes no arguments, not a function that takes a 2736 // single void argument. 2737 // We let through "const void" here because Sema::GetTypeForDeclarator 2738 // already checks for that case. 2739 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2740 FTI.ArgInfo[0].Param && 2741 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2742 // Empty arg list, don't push any params. 2743 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2744 2745 // In C++, the empty parameter-type-list must be spelled "void"; a 2746 // typedef of void is not permitted. 2747 if (getLangOptions().CPlusPlus && 2748 Param->getType().getUnqualifiedType() != Context.VoidTy) 2749 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2750 // FIXME: Leaks decl? 2751 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2752 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2753 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2754 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2755 Param->setDeclContext(NewFD); 2756 Params.push_back(Param); 2757 } 2758 } 2759 2760 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2761 // When we're declaring a function with a typedef, typeof, etc as in the 2762 // following example, we'll need to synthesize (unnamed) 2763 // parameters for use in the declaration. 2764 // 2765 // @code 2766 // typedef void fn(int); 2767 // fn f; 2768 // @endcode 2769 2770 // Synthesize a parameter for each argument type. 2771 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2772 AE = FT->arg_type_end(); AI != AE; ++AI) { 2773 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2774 SourceLocation(), 0, 2775 *AI, /*DInfo=*/0, 2776 VarDecl::None, 0); 2777 Param->setImplicit(); 2778 Params.push_back(Param); 2779 } 2780 } else { 2781 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2782 "Should not need args for typedef of non-prototype fn"); 2783 } 2784 // Finally, we know we have the right number of parameters, install them. 2785 NewFD->setParams(Context, Params.data(), Params.size()); 2786 2787 // If name lookup finds a previous declaration that is not in the 2788 // same scope as the new declaration, this may still be an 2789 // acceptable redeclaration. 2790 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2791 !(NewFD->hasLinkage() && 2792 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2793 PrevDecl = 0; 2794 2795 // If the declarator is a template-id, translate the parser's template 2796 // argument list into our AST format. 2797 bool HasExplicitTemplateArgs = false; 2798 llvm::SmallVector<TemplateArgument, 16> TemplateArgs; 2799 SourceLocation LAngleLoc, RAngleLoc; 2800 if (D.getKind() == Declarator::DK_TemplateId) { 2801 TemplateIdAnnotation *TemplateId = D.getTemplateId(); 2802 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2803 TemplateId->getTemplateArgs(), 2804 TemplateId->getTemplateArgIsType(), 2805 TemplateId->NumArgs); 2806 translateTemplateArguments(TemplateArgsPtr, 2807 TemplateId->getTemplateArgLocations(), 2808 TemplateArgs); 2809 TemplateArgsPtr.release(); 2810 2811 HasExplicitTemplateArgs = true; 2812 LAngleLoc = TemplateId->LAngleLoc; 2813 RAngleLoc = TemplateId->RAngleLoc; 2814 2815 if (FunctionTemplate) { 2816 // FIXME: Diagnose function template with explicit template 2817 // arguments. 2818 HasExplicitTemplateArgs = false; 2819 } else if (!isFunctionTemplateSpecialization && 2820 !D.getDeclSpec().isFriendSpecified()) { 2821 // We have encountered something that the user meant to be a 2822 // specialization (because it has explicitly-specified template 2823 // arguments) but that was not introduced with a "template<>" (or had 2824 // too few of them). 2825 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2826 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2827 << CodeModificationHint::CreateInsertion( 2828 D.getDeclSpec().getSourceRange().getBegin(), 2829 "template<> "); 2830 isFunctionTemplateSpecialization = true; 2831 } 2832 } 2833 2834 if (isFunctionTemplateSpecialization) { 2835 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2836 LAngleLoc, TemplateArgs.data(), 2837 TemplateArgs.size(), RAngleLoc, 2838 PrevDecl)) 2839 NewFD->setInvalidDecl(); 2840 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2841 CheckMemberSpecialization(NewFD, PrevDecl)) 2842 NewFD->setInvalidDecl(); 2843 2844 // Perform semantic checking on the function declaration. 2845 bool OverloadableAttrRequired = false; // FIXME: HACK! 2846 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2847 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2848 2849 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2850 // An out-of-line member function declaration must also be a 2851 // definition (C++ [dcl.meaning]p1). 2852 // Note that this is not the case for explicit specializations of 2853 // function templates or member functions of class templates, per 2854 // C++ [temp.expl.spec]p2. 2855 if (!IsFunctionDefinition && !isFriend && 2856 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2857 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2858 << D.getCXXScopeSpec().getRange(); 2859 NewFD->setInvalidDecl(); 2860 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2861 // The user tried to provide an out-of-line definition for a 2862 // function that is a member of a class or namespace, but there 2863 // was no such member function declared (C++ [class.mfct]p2, 2864 // C++ [namespace.memdef]p2). For example: 2865 // 2866 // class X { 2867 // void f() const; 2868 // }; 2869 // 2870 // void X::f() { } // ill-formed 2871 // 2872 // Complain about this problem, and attempt to suggest close 2873 // matches (e.g., those that differ only in cv-qualifiers and 2874 // whether the parameter types are references). 2875 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2876 << Name << DC << D.getCXXScopeSpec().getRange(); 2877 NewFD->setInvalidDecl(); 2878 2879 LookupResult Prev; 2880 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2881 assert(!Prev.isAmbiguous() && 2882 "Cannot have an ambiguity in previous-declaration lookup"); 2883 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2884 Func != FuncEnd; ++Func) { 2885 if (isa<FunctionDecl>(*Func) && 2886 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2887 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2888 } 2889 2890 PrevDecl = 0; 2891 } 2892 } 2893 2894 // Handle attributes. We need to have merged decls when handling attributes 2895 // (for example to check for conflicts, etc). 2896 // FIXME: This needs to happen before we merge declarations. Then, 2897 // let attribute merging cope with attribute conflicts. 2898 ProcessDeclAttributes(S, NewFD, D); 2899 2900 // attributes declared post-definition are currently ignored 2901 if (Redeclaration && PrevDecl) { 2902 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2903 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2904 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2905 Diag(Def->getLocation(), diag::note_previous_definition); 2906 } 2907 } 2908 2909 AddKnownFunctionAttributes(NewFD); 2910 2911 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2912 // If a function name is overloadable in C, then every function 2913 // with that name must be marked "overloadable". 2914 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2915 << Redeclaration << NewFD; 2916 if (PrevDecl) 2917 Diag(PrevDecl->getLocation(), 2918 diag::note_attribute_overloadable_prev_overload); 2919 NewFD->addAttr(::new (Context) OverloadableAttr()); 2920 } 2921 2922 // If this is a locally-scoped extern C function, update the 2923 // map of such names. 2924 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2925 && !NewFD->isInvalidDecl()) 2926 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2927 2928 // Set this FunctionDecl's range up to the right paren. 2929 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2930 2931 if (FunctionTemplate && NewFD->isInvalidDecl()) 2932 FunctionTemplate->setInvalidDecl(); 2933 2934 if (FunctionTemplate) 2935 return FunctionTemplate; 2936 2937 return NewFD; 2938} 2939 2940/// \brief Perform semantic checking of a new function declaration. 2941/// 2942/// Performs semantic analysis of the new function declaration 2943/// NewFD. This routine performs all semantic checking that does not 2944/// require the actual declarator involved in the declaration, and is 2945/// used both for the declaration of functions as they are parsed 2946/// (called via ActOnDeclarator) and for the declaration of functions 2947/// that have been instantiated via C++ template instantiation (called 2948/// via InstantiateDecl). 2949/// 2950/// \param IsExplicitSpecialiation whether this new function declaration is 2951/// an explicit specialization of the previous declaration. 2952/// 2953/// This sets NewFD->isInvalidDecl() to true if there was an error. 2954void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2955 bool IsExplicitSpecialization, 2956 bool &Redeclaration, 2957 bool &OverloadableAttrRequired) { 2958 // If NewFD is already known erroneous, don't do any of this checking. 2959 if (NewFD->isInvalidDecl()) 2960 return; 2961 2962 if (NewFD->getResultType()->isVariablyModifiedType()) { 2963 // Functions returning a variably modified type violate C99 6.7.5.2p2 2964 // because all functions have linkage. 2965 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2966 return NewFD->setInvalidDecl(); 2967 } 2968 2969 if (NewFD->isMain()) 2970 CheckMain(NewFD); 2971 2972 // Check for a previous declaration of this name. 2973 if (!PrevDecl && NewFD->isExternC()) { 2974 // Since we did not find anything by this name and we're declaring 2975 // an extern "C" function, look for a non-visible extern "C" 2976 // declaration with the same name. 2977 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2978 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2979 if (Pos != LocallyScopedExternalDecls.end()) 2980 PrevDecl = Pos->second; 2981 } 2982 2983 // Merge or overload the declaration with an existing declaration of 2984 // the same name, if appropriate. 2985 if (PrevDecl) { 2986 // Determine whether NewFD is an overload of PrevDecl or 2987 // a declaration that requires merging. If it's an overload, 2988 // there's no more work to do here; we'll just add the new 2989 // function to the scope. 2990 OverloadedFunctionDecl::function_iterator MatchedDecl; 2991 2992 if (!getLangOptions().CPlusPlus && 2993 AllowOverloadingOfFunction(PrevDecl, Context)) { 2994 OverloadableAttrRequired = true; 2995 2996 // Functions marked "overloadable" must have a prototype (that 2997 // we can't get through declaration merging). 2998 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 2999 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3000 << NewFD; 3001 Redeclaration = true; 3002 3003 // Turn this into a variadic function with no parameters. 3004 QualType R = Context.getFunctionType( 3005 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3006 0, 0, true, 0); 3007 NewFD->setType(R); 3008 return NewFD->setInvalidDecl(); 3009 } 3010 } 3011 3012 if (PrevDecl && 3013 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3014 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3015 Redeclaration = true; 3016 Decl *OldDecl = PrevDecl; 3017 3018 // If PrevDecl was an overloaded function, extract the 3019 // FunctionDecl that matched. 3020 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3021 OldDecl = *MatchedDecl; 3022 3023 // NewFD and OldDecl represent declarations that need to be 3024 // merged. 3025 if (MergeFunctionDecl(NewFD, OldDecl)) 3026 return NewFD->setInvalidDecl(); 3027 3028 if (FunctionTemplateDecl *OldTemplateDecl 3029 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3030 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3031 FunctionTemplateDecl *NewTemplateDecl 3032 = NewFD->getDescribedFunctionTemplate(); 3033 assert(NewTemplateDecl && "Template/non-template mismatch"); 3034 if (CXXMethodDecl *Method 3035 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3036 Method->setAccess(OldTemplateDecl->getAccess()); 3037 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3038 } 3039 3040 // If this is an explicit specialization of a member that is a function 3041 // template, mark it as a member specialization. 3042 if (IsExplicitSpecialization && 3043 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3044 NewTemplateDecl->setMemberSpecialization(); 3045 assert(OldTemplateDecl->isMemberSpecialization()); 3046 } 3047 } else { 3048 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3049 NewFD->setAccess(OldDecl->getAccess()); 3050 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3051 } 3052 } 3053 } 3054 3055 // Semantic checking for this function declaration (in isolation). 3056 if (getLangOptions().CPlusPlus) { 3057 // C++-specific checks. 3058 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3059 CheckConstructor(Constructor); 3060 } else if (isa<CXXDestructorDecl>(NewFD)) { 3061 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3062 QualType ClassType = Context.getTypeDeclType(Record); 3063 if (!ClassType->isDependentType()) { 3064 DeclarationName Name 3065 = Context.DeclarationNames.getCXXDestructorName( 3066 Context.getCanonicalType(ClassType)); 3067 if (NewFD->getDeclName() != Name) { 3068 Diag(NewFD->getLocation(), diag::err_destructor_name); 3069 return NewFD->setInvalidDecl(); 3070 } 3071 } 3072 Record->setUserDeclaredDestructor(true); 3073 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3074 // user-defined destructor. 3075 Record->setPOD(false); 3076 3077 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3078 // declared destructor. 3079 // FIXME: C++0x: don't do this for "= default" destructors 3080 Record->setHasTrivialDestructor(false); 3081 } else if (CXXConversionDecl *Conversion 3082 = dyn_cast<CXXConversionDecl>(NewFD)) 3083 ActOnConversionDeclarator(Conversion); 3084 3085 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3086 if (NewFD->isOverloadedOperator() && 3087 CheckOverloadedOperatorDeclaration(NewFD)) 3088 return NewFD->setInvalidDecl(); 3089 3090 // In C++, check default arguments now that we have merged decls. Unless 3091 // the lexical context is the class, because in this case this is done 3092 // during delayed parsing anyway. 3093 if (!CurContext->isRecord()) 3094 CheckCXXDefaultArguments(NewFD); 3095 } 3096} 3097 3098void Sema::CheckMain(FunctionDecl* FD) { 3099 // C++ [basic.start.main]p3: A program that declares main to be inline 3100 // or static is ill-formed. 3101 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3102 // shall not appear in a declaration of main. 3103 // static main is not an error under C99, but we should warn about it. 3104 bool isInline = FD->isInline(); 3105 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3106 if (isInline || isStatic) { 3107 unsigned diagID = diag::warn_unusual_main_decl; 3108 if (isInline || getLangOptions().CPlusPlus) 3109 diagID = diag::err_unusual_main_decl; 3110 3111 int which = isStatic + (isInline << 1) - 1; 3112 Diag(FD->getLocation(), diagID) << which; 3113 } 3114 3115 QualType T = FD->getType(); 3116 assert(T->isFunctionType() && "function decl is not of function type"); 3117 const FunctionType* FT = T->getAs<FunctionType>(); 3118 3119 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3120 // TODO: add a replacement fixit to turn the return type into 'int'. 3121 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3122 FD->setInvalidDecl(true); 3123 } 3124 3125 // Treat protoless main() as nullary. 3126 if (isa<FunctionNoProtoType>(FT)) return; 3127 3128 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3129 unsigned nparams = FTP->getNumArgs(); 3130 assert(FD->getNumParams() == nparams); 3131 3132 if (nparams > 3) { 3133 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3134 FD->setInvalidDecl(true); 3135 nparams = 3; 3136 } 3137 3138 // FIXME: a lot of the following diagnostics would be improved 3139 // if we had some location information about types. 3140 3141 QualType CharPP = 3142 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3143 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3144 3145 for (unsigned i = 0; i < nparams; ++i) { 3146 QualType AT = FTP->getArgType(i); 3147 3148 bool mismatch = true; 3149 3150 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3151 mismatch = false; 3152 else if (Expected[i] == CharPP) { 3153 // As an extension, the following forms are okay: 3154 // char const ** 3155 // char const * const * 3156 // char * const * 3157 3158 QualifierCollector qs; 3159 const PointerType* PT; 3160 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3161 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3162 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3163 qs.removeConst(); 3164 mismatch = !qs.empty(); 3165 } 3166 } 3167 3168 if (mismatch) { 3169 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3170 // TODO: suggest replacing given type with expected type 3171 FD->setInvalidDecl(true); 3172 } 3173 } 3174 3175 if (nparams == 1 && !FD->isInvalidDecl()) { 3176 Diag(FD->getLocation(), diag::warn_main_one_arg); 3177 } 3178} 3179 3180bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3181 // FIXME: Need strict checking. In C89, we need to check for 3182 // any assignment, increment, decrement, function-calls, or 3183 // commas outside of a sizeof. In C99, it's the same list, 3184 // except that the aforementioned are allowed in unevaluated 3185 // expressions. Everything else falls under the 3186 // "may accept other forms of constant expressions" exception. 3187 // (We never end up here for C++, so the constant expression 3188 // rules there don't matter.) 3189 if (Init->isConstantInitializer(Context)) 3190 return false; 3191 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3192 << Init->getSourceRange(); 3193 return true; 3194} 3195 3196void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3197 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3198} 3199 3200/// AddInitializerToDecl - Adds the initializer Init to the 3201/// declaration dcl. If DirectInit is true, this is C++ direct 3202/// initialization rather than copy initialization. 3203void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3204 Decl *RealDecl = dcl.getAs<Decl>(); 3205 // If there is no declaration, there was an error parsing it. Just ignore 3206 // the initializer. 3207 if (RealDecl == 0) 3208 return; 3209 3210 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3211 // With declarators parsed the way they are, the parser cannot 3212 // distinguish between a normal initializer and a pure-specifier. 3213 // Thus this grotesque test. 3214 IntegerLiteral *IL; 3215 Expr *Init = static_cast<Expr *>(init.get()); 3216 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3217 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3218 if (Method->isVirtualAsWritten()) { 3219 Method->setPure(); 3220 3221 // A class is abstract if at least one function is pure virtual. 3222 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3223 } else if (!Method->isInvalidDecl()) { 3224 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3225 << Method->getDeclName() << Init->getSourceRange(); 3226 Method->setInvalidDecl(); 3227 } 3228 } else { 3229 Diag(Method->getLocation(), diag::err_member_function_initialization) 3230 << Method->getDeclName() << Init->getSourceRange(); 3231 Method->setInvalidDecl(); 3232 } 3233 return; 3234 } 3235 3236 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3237 if (!VDecl) { 3238 if (getLangOptions().CPlusPlus && 3239 RealDecl->getLexicalDeclContext()->isRecord() && 3240 isa<NamedDecl>(RealDecl)) 3241 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3242 << cast<NamedDecl>(RealDecl)->getDeclName(); 3243 else 3244 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3245 RealDecl->setInvalidDecl(); 3246 return; 3247 } 3248 3249 if (!VDecl->getType()->isArrayType() && 3250 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3251 diag::err_typecheck_decl_incomplete_type)) { 3252 RealDecl->setInvalidDecl(); 3253 return; 3254 } 3255 3256 const VarDecl *Def = 0; 3257 if (VDecl->getDefinition(Def)) { 3258 Diag(VDecl->getLocation(), diag::err_redefinition) 3259 << VDecl->getDeclName(); 3260 Diag(Def->getLocation(), diag::note_previous_definition); 3261 VDecl->setInvalidDecl(); 3262 return; 3263 } 3264 3265 // Take ownership of the expression, now that we're sure we have somewhere 3266 // to put it. 3267 Expr *Init = init.takeAs<Expr>(); 3268 assert(Init && "missing initializer"); 3269 3270 // Get the decls type and save a reference for later, since 3271 // CheckInitializerTypes may change it. 3272 QualType DclT = VDecl->getType(), SavT = DclT; 3273 if (VDecl->isBlockVarDecl()) { 3274 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3275 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3276 VDecl->setInvalidDecl(); 3277 } else if (!VDecl->isInvalidDecl()) { 3278 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3279 VDecl->getDeclName(), DirectInit)) 3280 VDecl->setInvalidDecl(); 3281 3282 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3283 // Don't check invalid declarations to avoid emitting useless diagnostics. 3284 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3285 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3286 CheckForConstantInitializer(Init, DclT); 3287 } 3288 } 3289 } else if (VDecl->isStaticDataMember() && 3290 VDecl->getLexicalDeclContext()->isRecord()) { 3291 // This is an in-class initialization for a static data member, e.g., 3292 // 3293 // struct S { 3294 // static const int value = 17; 3295 // }; 3296 3297 // Attach the initializer 3298 VDecl->setInit(Context, Init); 3299 3300 // C++ [class.mem]p4: 3301 // A member-declarator can contain a constant-initializer only 3302 // if it declares a static member (9.4) of const integral or 3303 // const enumeration type, see 9.4.2. 3304 QualType T = VDecl->getType(); 3305 if (!T->isDependentType() && 3306 (!Context.getCanonicalType(T).isConstQualified() || 3307 !T->isIntegralType())) { 3308 Diag(VDecl->getLocation(), diag::err_member_initialization) 3309 << VDecl->getDeclName() << Init->getSourceRange(); 3310 VDecl->setInvalidDecl(); 3311 } else { 3312 // C++ [class.static.data]p4: 3313 // If a static data member is of const integral or const 3314 // enumeration type, its declaration in the class definition 3315 // can specify a constant-initializer which shall be an 3316 // integral constant expression (5.19). 3317 if (!Init->isTypeDependent() && 3318 !Init->getType()->isIntegralType()) { 3319 // We have a non-dependent, non-integral or enumeration type. 3320 Diag(Init->getSourceRange().getBegin(), 3321 diag::err_in_class_initializer_non_integral_type) 3322 << Init->getType() << Init->getSourceRange(); 3323 VDecl->setInvalidDecl(); 3324 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3325 // Check whether the expression is a constant expression. 3326 llvm::APSInt Value; 3327 SourceLocation Loc; 3328 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3329 Diag(Loc, diag::err_in_class_initializer_non_constant) 3330 << Init->getSourceRange(); 3331 VDecl->setInvalidDecl(); 3332 } else if (!VDecl->getType()->isDependentType()) 3333 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3334 } 3335 } 3336 } else if (VDecl->isFileVarDecl()) { 3337 if (VDecl->getStorageClass() == VarDecl::Extern) 3338 Diag(VDecl->getLocation(), diag::warn_extern_init); 3339 if (!VDecl->isInvalidDecl()) 3340 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3341 VDecl->getDeclName(), DirectInit)) 3342 VDecl->setInvalidDecl(); 3343 3344 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3345 // Don't check invalid declarations to avoid emitting useless diagnostics. 3346 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3347 // C99 6.7.8p4. All file scoped initializers need to be constant. 3348 CheckForConstantInitializer(Init, DclT); 3349 } 3350 } 3351 // If the type changed, it means we had an incomplete type that was 3352 // completed by the initializer. For example: 3353 // int ary[] = { 1, 3, 5 }; 3354 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3355 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3356 VDecl->setType(DclT); 3357 Init->setType(DclT); 3358 } 3359 3360 Init = MaybeCreateCXXExprWithTemporaries(Init, 3361 /*ShouldDestroyTemporaries=*/true); 3362 // Attach the initializer to the decl. 3363 VDecl->setInit(Context, Init); 3364 3365 // If the previous declaration of VDecl was a tentative definition, 3366 // remove it from the set of tentative definitions. 3367 if (VDecl->getPreviousDeclaration() && 3368 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3369 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3370 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3371 } 3372 3373 return; 3374} 3375 3376void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3377 bool TypeContainsUndeducedAuto) { 3378 Decl *RealDecl = dcl.getAs<Decl>(); 3379 3380 // If there is no declaration, there was an error parsing it. Just ignore it. 3381 if (RealDecl == 0) 3382 return; 3383 3384 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3385 QualType Type = Var->getType(); 3386 3387 // Record tentative definitions. 3388 if (Var->isTentativeDefinition(Context)) { 3389 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3390 InsertPair = 3391 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3392 3393 // Keep the latest definition in the map. If we see 'int i; int i;' we 3394 // want the second one in the map. 3395 InsertPair.first->second = Var; 3396 3397 // However, for the list, we don't care about the order, just make sure 3398 // that there are no dupes for a given declaration name. 3399 if (InsertPair.second) 3400 TentativeDefinitionList.push_back(Var->getDeclName()); 3401 } 3402 3403 // C++ [dcl.init.ref]p3: 3404 // The initializer can be omitted for a reference only in a 3405 // parameter declaration (8.3.5), in the declaration of a 3406 // function return type, in the declaration of a class member 3407 // within its class declaration (9.2), and where the extern 3408 // specifier is explicitly used. 3409 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3410 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3411 << Var->getDeclName() 3412 << SourceRange(Var->getLocation(), Var->getLocation()); 3413 Var->setInvalidDecl(); 3414 return; 3415 } 3416 3417 // C++0x [dcl.spec.auto]p3 3418 if (TypeContainsUndeducedAuto) { 3419 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3420 << Var->getDeclName() << Type; 3421 Var->setInvalidDecl(); 3422 return; 3423 } 3424 3425 // C++ [temp.expl.spec]p15: 3426 // An explicit specialization of a static data member of a template is a 3427 // definition if the declaration includes an initializer; otherwise, it 3428 // is a declaration. 3429 if (Var->isStaticDataMember() && 3430 Var->getInstantiatedFromStaticDataMember() && 3431 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3432 return; 3433 3434 // C++ [dcl.init]p9: 3435 // If no initializer is specified for an object, and the object 3436 // is of (possibly cv-qualified) non-POD class type (or array 3437 // thereof), the object shall be default-initialized; if the 3438 // object is of const-qualified type, the underlying class type 3439 // shall have a user-declared default constructor. 3440 // 3441 // FIXME: Diagnose the "user-declared default constructor" bit. 3442 if (getLangOptions().CPlusPlus) { 3443 QualType InitType = Type; 3444 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3445 InitType = Array->getElementType(); 3446 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3447 InitType->isRecordType() && !InitType->isDependentType()) { 3448 if (!RequireCompleteType(Var->getLocation(), InitType, 3449 diag::err_invalid_incomplete_type_use)) { 3450 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3451 3452 CXXConstructorDecl *Constructor 3453 = PerformInitializationByConstructor(InitType, 3454 MultiExprArg(*this, 0, 0), 3455 Var->getLocation(), 3456 SourceRange(Var->getLocation(), 3457 Var->getLocation()), 3458 Var->getDeclName(), 3459 IK_Default, 3460 ConstructorArgs); 3461 3462 // FIXME: Location info for the variable initialization? 3463 if (!Constructor) 3464 Var->setInvalidDecl(); 3465 else { 3466 // FIXME: Cope with initialization of arrays 3467 if (!Constructor->isTrivial() && 3468 InitializeVarWithConstructor(Var, Constructor, InitType, 3469 move_arg(ConstructorArgs))) 3470 Var->setInvalidDecl(); 3471 3472 FinalizeVarWithDestructor(Var, InitType); 3473 } 3474 } else { 3475 Var->setInvalidDecl(); 3476 } 3477 } 3478 } 3479 3480#if 0 3481 // FIXME: Temporarily disabled because we are not properly parsing 3482 // linkage specifications on declarations, e.g., 3483 // 3484 // extern "C" const CGPoint CGPointerZero; 3485 // 3486 // C++ [dcl.init]p9: 3487 // 3488 // If no initializer is specified for an object, and the 3489 // object is of (possibly cv-qualified) non-POD class type (or 3490 // array thereof), the object shall be default-initialized; if 3491 // the object is of const-qualified type, the underlying class 3492 // type shall have a user-declared default 3493 // constructor. Otherwise, if no initializer is specified for 3494 // an object, the object and its subobjects, if any, have an 3495 // indeterminate initial value; if the object or any of its 3496 // subobjects are of const-qualified type, the program is 3497 // ill-formed. 3498 // 3499 // This isn't technically an error in C, so we don't diagnose it. 3500 // 3501 // FIXME: Actually perform the POD/user-defined default 3502 // constructor check. 3503 if (getLangOptions().CPlusPlus && 3504 Context.getCanonicalType(Type).isConstQualified() && 3505 !Var->hasExternalStorage()) 3506 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3507 << Var->getName() 3508 << SourceRange(Var->getLocation(), Var->getLocation()); 3509#endif 3510 } 3511} 3512 3513Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3514 DeclPtrTy *Group, 3515 unsigned NumDecls) { 3516 llvm::SmallVector<Decl*, 8> Decls; 3517 3518 if (DS.isTypeSpecOwned()) 3519 Decls.push_back((Decl*)DS.getTypeRep()); 3520 3521 for (unsigned i = 0; i != NumDecls; ++i) 3522 if (Decl *D = Group[i].getAs<Decl>()) 3523 Decls.push_back(D); 3524 3525 // Perform semantic analysis that depends on having fully processed both 3526 // the declarator and initializer. 3527 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3528 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3529 if (!IDecl) 3530 continue; 3531 QualType T = IDecl->getType(); 3532 3533 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3534 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3535 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3536 if (T->isDependentType()) { 3537 // If T is dependent, we should not require a complete type. 3538 // (RequireCompleteType shouldn't be called with dependent types.) 3539 // But we still can at least check if we've got an array of unspecified 3540 // size without an initializer. 3541 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3542 !IDecl->getInit()) { 3543 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3544 << T; 3545 IDecl->setInvalidDecl(); 3546 } 3547 } else if (!IDecl->isInvalidDecl()) { 3548 // If T is an incomplete array type with an initializer list that is 3549 // dependent on something, its size has not been fixed. We could attempt 3550 // to fix the size for such arrays, but we would still have to check 3551 // here for initializers containing a C++0x vararg expansion, e.g. 3552 // template <typename... Args> void f(Args... args) { 3553 // int vals[] = { args }; 3554 // } 3555 const IncompleteArrayType *IAT = T->getAs<IncompleteArrayType>(); 3556 Expr *Init = IDecl->getInit(); 3557 if (IAT && Init && 3558 (Init->isTypeDependent() || Init->isValueDependent())) { 3559 // Check that the member type of the array is complete, at least. 3560 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3561 diag::err_typecheck_decl_incomplete_type)) 3562 IDecl->setInvalidDecl(); 3563 } else if (RequireCompleteType(IDecl->getLocation(), T, 3564 diag::err_typecheck_decl_incomplete_type)) 3565 IDecl->setInvalidDecl(); 3566 } 3567 } 3568 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3569 // object that has file scope without an initializer, and without a 3570 // storage-class specifier or with the storage-class specifier "static", 3571 // constitutes a tentative definition. Note: A tentative definition with 3572 // external linkage is valid (C99 6.2.2p5). 3573 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3574 if (const IncompleteArrayType *ArrayT 3575 = Context.getAsIncompleteArrayType(T)) { 3576 if (RequireCompleteType(IDecl->getLocation(), 3577 ArrayT->getElementType(), 3578 diag::err_illegal_decl_array_incomplete_type)) 3579 IDecl->setInvalidDecl(); 3580 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3581 // C99 6.9.2p3: If the declaration of an identifier for an object is 3582 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3583 // declared type shall not be an incomplete type. 3584 // NOTE: code such as the following 3585 // static struct s; 3586 // struct s { int a; }; 3587 // is accepted by gcc. Hence here we issue a warning instead of 3588 // an error and we do not invalidate the static declaration. 3589 // NOTE: to avoid multiple warnings, only check the first declaration. 3590 if (IDecl->getPreviousDeclaration() == 0) 3591 RequireCompleteType(IDecl->getLocation(), T, 3592 diag::ext_typecheck_decl_incomplete_type); 3593 } 3594 } 3595 } 3596 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3597 Decls.data(), Decls.size())); 3598} 3599 3600 3601/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3602/// to introduce parameters into function prototype scope. 3603Sema::DeclPtrTy 3604Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3605 const DeclSpec &DS = D.getDeclSpec(); 3606 3607 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3608 VarDecl::StorageClass StorageClass = VarDecl::None; 3609 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3610 StorageClass = VarDecl::Register; 3611 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3612 Diag(DS.getStorageClassSpecLoc(), 3613 diag::err_invalid_storage_class_in_func_decl); 3614 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3615 } 3616 3617 if (D.getDeclSpec().isThreadSpecified()) 3618 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3619 3620 DiagnoseFunctionSpecifiers(D); 3621 3622 // Check that there are no default arguments inside the type of this 3623 // parameter (C++ only). 3624 if (getLangOptions().CPlusPlus) 3625 CheckExtraCXXDefaultArguments(D); 3626 3627 DeclaratorInfo *DInfo = 0; 3628 TagDecl *OwnedDecl = 0; 3629 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, /*Skip=*/0, 3630 &OwnedDecl); 3631 3632 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3633 // C++ [dcl.fct]p6: 3634 // Types shall not be defined in return or parameter types. 3635 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3636 << Context.getTypeDeclType(OwnedDecl); 3637 } 3638 3639 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3640 // Can this happen for params? We already checked that they don't conflict 3641 // among each other. Here they can only shadow globals, which is ok. 3642 IdentifierInfo *II = D.getIdentifier(); 3643 if (II) { 3644 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3645 if (PrevDecl->isTemplateParameter()) { 3646 // Maybe we will complain about the shadowed template parameter. 3647 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3648 // Just pretend that we didn't see the previous declaration. 3649 PrevDecl = 0; 3650 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3651 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3652 3653 // Recover by removing the name 3654 II = 0; 3655 D.SetIdentifier(0, D.getIdentifierLoc()); 3656 } 3657 } 3658 } 3659 3660 // Parameters can not be abstract class types. 3661 // For record types, this is done by the AbstractClassUsageDiagnoser once 3662 // the class has been completely parsed. 3663 if (!CurContext->isRecord() && 3664 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3665 diag::err_abstract_type_in_decl, 3666 AbstractParamType)) 3667 D.setInvalidType(true); 3668 3669 QualType T = adjustParameterType(parmDeclType); 3670 3671 ParmVarDecl *New 3672 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3673 T, DInfo, StorageClass, 0); 3674 3675 if (D.isInvalidType()) 3676 New->setInvalidDecl(); 3677 3678 // Parameter declarators cannot be interface types. All ObjC objects are 3679 // passed by reference. 3680 if (T->isObjCInterfaceType()) { 3681 Diag(D.getIdentifierLoc(), 3682 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3683 New->setInvalidDecl(); 3684 } 3685 3686 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3687 if (D.getCXXScopeSpec().isSet()) { 3688 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3689 << D.getCXXScopeSpec().getRange(); 3690 New->setInvalidDecl(); 3691 } 3692 3693 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3694 // duration shall not be qualified by an address-space qualifier." 3695 // Since all parameters have automatic store duration, they can not have 3696 // an address space. 3697 if (T.getAddressSpace() != 0) { 3698 Diag(D.getIdentifierLoc(), 3699 diag::err_arg_with_address_space); 3700 New->setInvalidDecl(); 3701 } 3702 3703 3704 // Add the parameter declaration into this scope. 3705 S->AddDecl(DeclPtrTy::make(New)); 3706 if (II) 3707 IdResolver.AddDecl(New); 3708 3709 ProcessDeclAttributes(S, New, D); 3710 3711 if (New->hasAttr<BlocksAttr>()) { 3712 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3713 } 3714 return DeclPtrTy::make(New); 3715} 3716 3717void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3718 SourceLocation LocAfterDecls) { 3719 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3720 "Not a function declarator!"); 3721 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3722 3723 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3724 // for a K&R function. 3725 if (!FTI.hasPrototype) { 3726 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3727 --i; 3728 if (FTI.ArgInfo[i].Param == 0) { 3729 llvm::SmallString<256> Code; 3730 llvm::raw_svector_ostream(Code) << " int " 3731 << FTI.ArgInfo[i].Ident->getName() 3732 << ";\n"; 3733 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3734 << FTI.ArgInfo[i].Ident 3735 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3736 3737 // Implicitly declare the argument as type 'int' for lack of a better 3738 // type. 3739 DeclSpec DS; 3740 const char* PrevSpec; // unused 3741 unsigned DiagID; // unused 3742 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3743 PrevSpec, DiagID); 3744 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3745 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3746 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3747 } 3748 } 3749 } 3750} 3751 3752Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3753 Declarator &D) { 3754 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3755 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3756 "Not a function declarator!"); 3757 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3758 3759 if (FTI.hasPrototype) { 3760 // FIXME: Diagnose arguments without names in C. 3761 } 3762 3763 Scope *ParentScope = FnBodyScope->getParent(); 3764 3765 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3766 MultiTemplateParamsArg(*this), 3767 /*IsFunctionDefinition=*/true); 3768 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3769} 3770 3771Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3772 if (!D) 3773 return D; 3774 FunctionDecl *FD = 0; 3775 3776 if (FunctionTemplateDecl *FunTmpl 3777 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3778 FD = FunTmpl->getTemplatedDecl(); 3779 else 3780 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3781 3782 CurFunctionNeedsScopeChecking = false; 3783 3784 // See if this is a redefinition. 3785 const FunctionDecl *Definition; 3786 if (FD->getBody(Definition)) { 3787 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3788 Diag(Definition->getLocation(), diag::note_previous_definition); 3789 } 3790 3791 // Builtin functions cannot be defined. 3792 if (unsigned BuiltinID = FD->getBuiltinID()) { 3793 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3794 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3795 FD->setInvalidDecl(); 3796 } 3797 } 3798 3799 // The return type of a function definition must be complete 3800 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3801 QualType ResultType = FD->getResultType(); 3802 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3803 !FD->isInvalidDecl() && 3804 RequireCompleteType(FD->getLocation(), ResultType, 3805 diag::err_func_def_incomplete_result)) 3806 FD->setInvalidDecl(); 3807 3808 // GNU warning -Wmissing-prototypes: 3809 // Warn if a global function is defined without a previous 3810 // prototype declaration. This warning is issued even if the 3811 // definition itself provides a prototype. The aim is to detect 3812 // global functions that fail to be declared in header files. 3813 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3814 !FD->isMain()) { 3815 bool MissingPrototype = true; 3816 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3817 Prev; Prev = Prev->getPreviousDeclaration()) { 3818 // Ignore any declarations that occur in function or method 3819 // scope, because they aren't visible from the header. 3820 if (Prev->getDeclContext()->isFunctionOrMethod()) 3821 continue; 3822 3823 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3824 break; 3825 } 3826 3827 if (MissingPrototype) 3828 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3829 } 3830 3831 if (FnBodyScope) 3832 PushDeclContext(FnBodyScope, FD); 3833 3834 // Check the validity of our function parameters 3835 CheckParmsForFunctionDef(FD); 3836 3837 // Introduce our parameters into the function scope 3838 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3839 ParmVarDecl *Param = FD->getParamDecl(p); 3840 Param->setOwningFunction(FD); 3841 3842 // If this has an identifier, add it to the scope stack. 3843 if (Param->getIdentifier() && FnBodyScope) 3844 PushOnScopeChains(Param, FnBodyScope); 3845 } 3846 3847 // Checking attributes of current function definition 3848 // dllimport attribute. 3849 if (FD->getAttr<DLLImportAttr>() && 3850 (!FD->getAttr<DLLExportAttr>())) { 3851 // dllimport attribute cannot be applied to definition. 3852 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3853 Diag(FD->getLocation(), 3854 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3855 << "dllimport"; 3856 FD->setInvalidDecl(); 3857 return DeclPtrTy::make(FD); 3858 } else { 3859 // If a symbol previously declared dllimport is later defined, the 3860 // attribute is ignored in subsequent references, and a warning is 3861 // emitted. 3862 Diag(FD->getLocation(), 3863 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3864 << FD->getNameAsCString() << "dllimport"; 3865 } 3866 } 3867 return DeclPtrTy::make(FD); 3868} 3869 3870Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3871 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3872} 3873 3874Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3875 bool IsInstantiation) { 3876 Decl *dcl = D.getAs<Decl>(); 3877 Stmt *Body = BodyArg.takeAs<Stmt>(); 3878 3879 FunctionDecl *FD = 0; 3880 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3881 if (FunTmpl) 3882 FD = FunTmpl->getTemplatedDecl(); 3883 else 3884 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3885 3886 if (FD) { 3887 FD->setBody(Body); 3888 if (FD->isMain()) 3889 // C and C++ allow for main to automagically return 0. 3890 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3891 FD->setHasImplicitReturnZero(true); 3892 else 3893 CheckFallThroughForFunctionDef(FD, Body); 3894 3895 if (!FD->isInvalidDecl()) 3896 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3897 3898 // C++ [basic.def.odr]p2: 3899 // [...] A virtual member function is used if it is not pure. [...] 3900 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3901 if (Method->isVirtual() && !Method->isPure()) 3902 MarkDeclarationReferenced(Method->getLocation(), Method); 3903 3904 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3905 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3906 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3907 MD->setBody(Body); 3908 CheckFallThroughForFunctionDef(MD, Body); 3909 MD->setEndLoc(Body->getLocEnd()); 3910 3911 if (!MD->isInvalidDecl()) 3912 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3913 } else { 3914 Body->Destroy(Context); 3915 return DeclPtrTy(); 3916 } 3917 if (!IsInstantiation) 3918 PopDeclContext(); 3919 3920 // Verify and clean out per-function state. 3921 3922 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3923 3924 // Check goto/label use. 3925 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3926 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3927 LabelStmt *L = I->second; 3928 3929 // Verify that we have no forward references left. If so, there was a goto 3930 // or address of a label taken, but no definition of it. Label fwd 3931 // definitions are indicated with a null substmt. 3932 if (L->getSubStmt() != 0) 3933 continue; 3934 3935 // Emit error. 3936 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3937 3938 // At this point, we have gotos that use the bogus label. Stitch it into 3939 // the function body so that they aren't leaked and that the AST is well 3940 // formed. 3941 if (Body == 0) { 3942 // The whole function wasn't parsed correctly, just delete this. 3943 L->Destroy(Context); 3944 continue; 3945 } 3946 3947 // Otherwise, the body is valid: we want to stitch the label decl into the 3948 // function somewhere so that it is properly owned and so that the goto 3949 // has a valid target. Do this by creating a new compound stmt with the 3950 // label in it. 3951 3952 // Give the label a sub-statement. 3953 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3954 3955 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3956 cast<CXXTryStmt>(Body)->getTryBlock() : 3957 cast<CompoundStmt>(Body); 3958 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3959 Elements.push_back(L); 3960 Compound->setStmts(Context, &Elements[0], Elements.size()); 3961 } 3962 FunctionLabelMap.clear(); 3963 3964 if (!Body) return D; 3965 3966 // Verify that that gotos and switch cases don't jump into scopes illegally. 3967 if (CurFunctionNeedsScopeChecking) 3968 DiagnoseInvalidJumps(Body); 3969 3970 // C++ constructors that have function-try-blocks can't have return 3971 // statements in the handlers of that block. (C++ [except.handle]p14) 3972 // Verify this. 3973 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3974 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3975 3976 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3977 computeBaseOrMembersToDestroy(Destructor); 3978 return D; 3979} 3980 3981/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3982/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3983NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3984 IdentifierInfo &II, Scope *S) { 3985 // Before we produce a declaration for an implicitly defined 3986 // function, see whether there was a locally-scoped declaration of 3987 // this name as a function or variable. If so, use that 3988 // (non-visible) declaration, and complain about it. 3989 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3990 = LocallyScopedExternalDecls.find(&II); 3991 if (Pos != LocallyScopedExternalDecls.end()) { 3992 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3993 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3994 return Pos->second; 3995 } 3996 3997 // Extension in C99. Legal in C90, but warn about it. 3998 if (II.getName().startswith("__builtin_")) 3999 Diag(Loc, diag::warn_builtin_unknown) << &II; 4000 else if (getLangOptions().C99) 4001 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4002 else 4003 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4004 4005 // Set a Declarator for the implicit definition: int foo(); 4006 const char *Dummy; 4007 DeclSpec DS; 4008 unsigned DiagID; 4009 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4010 Error = Error; // Silence warning. 4011 assert(!Error && "Error setting up implicit decl!"); 4012 Declarator D(DS, Declarator::BlockContext); 4013 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4014 0, 0, false, SourceLocation(), 4015 false, 0,0,0, Loc, Loc, D), 4016 SourceLocation()); 4017 D.SetIdentifier(&II, Loc); 4018 4019 // Insert this function into translation-unit scope. 4020 4021 DeclContext *PrevDC = CurContext; 4022 CurContext = Context.getTranslationUnitDecl(); 4023 4024 FunctionDecl *FD = 4025 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4026 FD->setImplicit(); 4027 4028 CurContext = PrevDC; 4029 4030 AddKnownFunctionAttributes(FD); 4031 4032 return FD; 4033} 4034 4035/// \brief Adds any function attributes that we know a priori based on 4036/// the declaration of this function. 4037/// 4038/// These attributes can apply both to implicitly-declared builtins 4039/// (like __builtin___printf_chk) or to library-declared functions 4040/// like NSLog or printf. 4041void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4042 if (FD->isInvalidDecl()) 4043 return; 4044 4045 // If this is a built-in function, map its builtin attributes to 4046 // actual attributes. 4047 if (unsigned BuiltinID = FD->getBuiltinID()) { 4048 // Handle printf-formatting attributes. 4049 unsigned FormatIdx; 4050 bool HasVAListArg; 4051 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4052 if (!FD->getAttr<FormatAttr>()) 4053 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4054 HasVAListArg ? 0 : FormatIdx + 2)); 4055 } 4056 4057 // Mark const if we don't care about errno and that is the only 4058 // thing preventing the function from being const. This allows 4059 // IRgen to use LLVM intrinsics for such functions. 4060 if (!getLangOptions().MathErrno && 4061 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4062 if (!FD->getAttr<ConstAttr>()) 4063 FD->addAttr(::new (Context) ConstAttr()); 4064 } 4065 4066 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4067 FD->addAttr(::new (Context) NoReturnAttr()); 4068 } 4069 4070 IdentifierInfo *Name = FD->getIdentifier(); 4071 if (!Name) 4072 return; 4073 if ((!getLangOptions().CPlusPlus && 4074 FD->getDeclContext()->isTranslationUnit()) || 4075 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4076 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4077 LinkageSpecDecl::lang_c)) { 4078 // Okay: this could be a libc/libm/Objective-C function we know 4079 // about. 4080 } else 4081 return; 4082 4083 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4084 // FIXME: NSLog and NSLogv should be target specific 4085 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4086 // FIXME: We known better than our headers. 4087 const_cast<FormatAttr *>(Format)->setType("printf"); 4088 } else 4089 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4090 Name->isStr("NSLogv") ? 0 : 2)); 4091 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4092 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4093 // target-specific builtins, perhaps? 4094 if (!FD->getAttr<FormatAttr>()) 4095 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4096 Name->isStr("vasprintf") ? 0 : 3)); 4097 } 4098} 4099 4100TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 4101 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4102 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4103 4104 // Scope manipulation handled by caller. 4105 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4106 D.getIdentifierLoc(), 4107 D.getIdentifier(), 4108 T); 4109 4110 if (const TagType *TT = T->getAs<TagType>()) { 4111 TagDecl *TD = TT->getDecl(); 4112 4113 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4114 // keep track of the TypedefDecl. 4115 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4116 TD->setTypedefForAnonDecl(NewTD); 4117 } 4118 4119 if (D.isInvalidType()) 4120 NewTD->setInvalidDecl(); 4121 return NewTD; 4122} 4123 4124 4125/// \brief Determine whether a tag with a given kind is acceptable 4126/// as a redeclaration of the given tag declaration. 4127/// 4128/// \returns true if the new tag kind is acceptable, false otherwise. 4129bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4130 TagDecl::TagKind NewTag, 4131 SourceLocation NewTagLoc, 4132 const IdentifierInfo &Name) { 4133 // C++ [dcl.type.elab]p3: 4134 // The class-key or enum keyword present in the 4135 // elaborated-type-specifier shall agree in kind with the 4136 // declaration to which the name in theelaborated-type-specifier 4137 // refers. This rule also applies to the form of 4138 // elaborated-type-specifier that declares a class-name or 4139 // friend class since it can be construed as referring to the 4140 // definition of the class. Thus, in any 4141 // elaborated-type-specifier, the enum keyword shall be used to 4142 // refer to an enumeration (7.2), the union class-keyshall be 4143 // used to refer to a union (clause 9), and either the class or 4144 // struct class-key shall be used to refer to a class (clause 9) 4145 // declared using the class or struct class-key. 4146 TagDecl::TagKind OldTag = Previous->getTagKind(); 4147 if (OldTag == NewTag) 4148 return true; 4149 4150 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4151 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4152 // Warn about the struct/class tag mismatch. 4153 bool isTemplate = false; 4154 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4155 isTemplate = Record->getDescribedClassTemplate(); 4156 4157 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4158 << (NewTag == TagDecl::TK_class) 4159 << isTemplate << &Name 4160 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4161 OldTag == TagDecl::TK_class? "class" : "struct"); 4162 Diag(Previous->getLocation(), diag::note_previous_use); 4163 return true; 4164 } 4165 return false; 4166} 4167 4168/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4169/// former case, Name will be non-null. In the later case, Name will be null. 4170/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4171/// reference/declaration/definition of a tag. 4172Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4173 SourceLocation KWLoc, const CXXScopeSpec &SS, 4174 IdentifierInfo *Name, SourceLocation NameLoc, 4175 AttributeList *Attr, AccessSpecifier AS, 4176 MultiTemplateParamsArg TemplateParameterLists, 4177 bool &OwnedDecl, bool &IsDependent) { 4178 // If this is not a definition, it must have a name. 4179 assert((Name != 0 || TUK == TUK_Definition) && 4180 "Nameless record must be a definition!"); 4181 4182 OwnedDecl = false; 4183 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4184 4185 // FIXME: Check explicit specializations more carefully. 4186 bool isExplicitSpecialization = false; 4187 if (TUK != TUK_Reference) { 4188 if (TemplateParameterList *TemplateParams 4189 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4190 (TemplateParameterList**)TemplateParameterLists.get(), 4191 TemplateParameterLists.size(), 4192 isExplicitSpecialization)) { 4193 if (TemplateParams->size() > 0) { 4194 // This is a declaration or definition of a class template (which may 4195 // be a member of another template). 4196 OwnedDecl = false; 4197 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4198 SS, Name, NameLoc, Attr, 4199 TemplateParams, 4200 AS); 4201 TemplateParameterLists.release(); 4202 return Result.get(); 4203 } else { 4204 // The "template<>" header is extraneous. 4205 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4206 << ElaboratedType::getNameForTagKind(Kind) << Name; 4207 isExplicitSpecialization = true; 4208 } 4209 } 4210 4211 TemplateParameterLists.release(); 4212 } 4213 4214 DeclContext *SearchDC = CurContext; 4215 DeclContext *DC = CurContext; 4216 NamedDecl *PrevDecl = 0; 4217 bool isStdBadAlloc = false; 4218 bool Invalid = false; 4219 4220 bool RedeclarationOnly = (TUK != TUK_Reference); 4221 4222 if (Name && SS.isNotEmpty()) { 4223 // We have a nested-name tag ('struct foo::bar'). 4224 4225 // Check for invalid 'foo::'. 4226 if (SS.isInvalid()) { 4227 Name = 0; 4228 goto CreateNewDecl; 4229 } 4230 4231 // If this is a friend or a reference to a class in a dependent 4232 // context, don't try to make a decl for it. 4233 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4234 DC = computeDeclContext(SS, false); 4235 if (!DC) { 4236 IsDependent = true; 4237 return DeclPtrTy(); 4238 } 4239 } 4240 4241 if (RequireCompleteDeclContext(SS)) 4242 return DeclPtrTy::make((Decl *)0); 4243 4244 DC = computeDeclContext(SS, true); 4245 SearchDC = DC; 4246 // Look-up name inside 'foo::'. 4247 LookupResult R; 4248 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4249 4250 if (R.isAmbiguous()) { 4251 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4252 return DeclPtrTy(); 4253 } 4254 4255 if (R.getKind() == LookupResult::Found) 4256 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4257 4258 // A tag 'foo::bar' must already exist. 4259 if (!PrevDecl) { 4260 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4261 Name = 0; 4262 Invalid = true; 4263 goto CreateNewDecl; 4264 } 4265 } else if (Name) { 4266 // If this is a named struct, check to see if there was a previous forward 4267 // declaration or definition. 4268 // FIXME: We're looking into outer scopes here, even when we 4269 // shouldn't be. Doing so can result in ambiguities that we 4270 // shouldn't be diagnosing. 4271 LookupResult R; 4272 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4273 if (R.isAmbiguous()) { 4274 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4275 // FIXME: This is not best way to recover from case like: 4276 // 4277 // struct S s; 4278 // 4279 // causes needless "incomplete type" error later. 4280 Name = 0; 4281 PrevDecl = 0; 4282 Invalid = true; 4283 } else 4284 PrevDecl = R.getAsSingleDecl(Context); 4285 4286 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4287 // FIXME: This makes sure that we ignore the contexts associated 4288 // with C structs, unions, and enums when looking for a matching 4289 // tag declaration or definition. See the similar lookup tweak 4290 // in Sema::LookupName; is there a better way to deal with this? 4291 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4292 SearchDC = SearchDC->getParent(); 4293 } 4294 } 4295 4296 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4297 // Maybe we will complain about the shadowed template parameter. 4298 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4299 // Just pretend that we didn't see the previous declaration. 4300 PrevDecl = 0; 4301 } 4302 4303 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4304 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4305 // This is a declaration of or a reference to "std::bad_alloc". 4306 isStdBadAlloc = true; 4307 4308 if (!PrevDecl && StdBadAlloc) { 4309 // std::bad_alloc has been implicitly declared (but made invisible to 4310 // name lookup). Fill in this implicit declaration as the previous 4311 // declaration, so that the declarations get chained appropriately. 4312 PrevDecl = StdBadAlloc; 4313 } 4314 } 4315 4316 if (PrevDecl) { 4317 // Check whether the previous declaration is usable. 4318 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 4319 4320 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4321 // If this is a use of a previous tag, or if the tag is already declared 4322 // in the same scope (so that the definition/declaration completes or 4323 // rementions the tag), reuse the decl. 4324 if (TUK == TUK_Reference || TUK == TUK_Friend || 4325 isDeclInScope(PrevDecl, SearchDC, S)) { 4326 // Make sure that this wasn't declared as an enum and now used as a 4327 // struct or something similar. 4328 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4329 bool SafeToContinue 4330 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4331 Kind != TagDecl::TK_enum); 4332 if (SafeToContinue) 4333 Diag(KWLoc, diag::err_use_with_wrong_tag) 4334 << Name 4335 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4336 PrevTagDecl->getKindName()); 4337 else 4338 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4339 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4340 4341 if (SafeToContinue) 4342 Kind = PrevTagDecl->getTagKind(); 4343 else { 4344 // Recover by making this an anonymous redefinition. 4345 Name = 0; 4346 PrevDecl = 0; 4347 Invalid = true; 4348 } 4349 } 4350 4351 if (!Invalid) { 4352 // If this is a use, just return the declaration we found. 4353 4354 // FIXME: In the future, return a variant or some other clue 4355 // for the consumer of this Decl to know it doesn't own it. 4356 // For our current ASTs this shouldn't be a problem, but will 4357 // need to be changed with DeclGroups. 4358 if (TUK == TUK_Reference || TUK == TUK_Friend) 4359 return DeclPtrTy::make(PrevDecl); 4360 4361 // Diagnose attempts to redefine a tag. 4362 if (TUK == TUK_Definition) { 4363 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4364 // If we're defining a specialization and the previous definition 4365 // is from an implicit instantiation, don't emit an error 4366 // here; we'll catch this in the general case below. 4367 if (!isExplicitSpecialization || 4368 !isa<CXXRecordDecl>(Def) || 4369 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4370 == TSK_ExplicitSpecialization) { 4371 Diag(NameLoc, diag::err_redefinition) << Name; 4372 Diag(Def->getLocation(), diag::note_previous_definition); 4373 // If this is a redefinition, recover by making this 4374 // struct be anonymous, which will make any later 4375 // references get the previous definition. 4376 Name = 0; 4377 PrevDecl = 0; 4378 Invalid = true; 4379 } 4380 } else { 4381 // If the type is currently being defined, complain 4382 // about a nested redefinition. 4383 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4384 if (Tag->isBeingDefined()) { 4385 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4386 Diag(PrevTagDecl->getLocation(), 4387 diag::note_previous_definition); 4388 Name = 0; 4389 PrevDecl = 0; 4390 Invalid = true; 4391 } 4392 } 4393 4394 // Okay, this is definition of a previously declared or referenced 4395 // tag PrevDecl. We're going to create a new Decl for it. 4396 } 4397 } 4398 // If we get here we have (another) forward declaration or we 4399 // have a definition. Just create a new decl. 4400 4401 } else { 4402 // If we get here, this is a definition of a new tag type in a nested 4403 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4404 // new decl/type. We set PrevDecl to NULL so that the entities 4405 // have distinct types. 4406 PrevDecl = 0; 4407 } 4408 // If we get here, we're going to create a new Decl. If PrevDecl 4409 // is non-NULL, it's a definition of the tag declared by 4410 // PrevDecl. If it's NULL, we have a new definition. 4411 } else { 4412 // PrevDecl is a namespace, template, or anything else 4413 // that lives in the IDNS_Tag identifier namespace. 4414 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4415 // The tag name clashes with a namespace name, issue an error and 4416 // recover by making this tag be anonymous. 4417 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4418 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4419 Name = 0; 4420 PrevDecl = 0; 4421 Invalid = true; 4422 } else { 4423 // The existing declaration isn't relevant to us; we're in a 4424 // new scope, so clear out the previous declaration. 4425 PrevDecl = 0; 4426 } 4427 } 4428 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4429 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4430 // C++ [basic.scope.pdecl]p5: 4431 // -- for an elaborated-type-specifier of the form 4432 // 4433 // class-key identifier 4434 // 4435 // if the elaborated-type-specifier is used in the 4436 // decl-specifier-seq or parameter-declaration-clause of a 4437 // function defined in namespace scope, the identifier is 4438 // declared as a class-name in the namespace that contains 4439 // the declaration; otherwise, except as a friend 4440 // declaration, the identifier is declared in the smallest 4441 // non-class, non-function-prototype scope that contains the 4442 // declaration. 4443 // 4444 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4445 // C structs and unions. 4446 // 4447 // GNU C also supports this behavior as part of its incomplete 4448 // enum types extension, while GNU C++ does not. 4449 // 4450 // Find the context where we'll be declaring the tag. 4451 // FIXME: We would like to maintain the current DeclContext as the 4452 // lexical context, 4453 while (SearchDC->isRecord()) 4454 SearchDC = SearchDC->getParent(); 4455 4456 // Find the scope where we'll be declaring the tag. 4457 while (S->isClassScope() || 4458 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4459 ((S->getFlags() & Scope::DeclScope) == 0) || 4460 (S->getEntity() && 4461 ((DeclContext *)S->getEntity())->isTransparentContext())) 4462 S = S->getParent(); 4463 4464 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4465 // C++ [namespace.memdef]p3: 4466 // If a friend declaration in a non-local class first declares a 4467 // class or function, the friend class or function is a member of 4468 // the innermost enclosing namespace. 4469 while (!SearchDC->isFileContext()) 4470 SearchDC = SearchDC->getParent(); 4471 4472 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4473 while (S->getEntity() != SearchDC) 4474 S = S->getParent(); 4475 } 4476 4477CreateNewDecl: 4478 4479 // If there is an identifier, use the location of the identifier as the 4480 // location of the decl, otherwise use the location of the struct/union 4481 // keyword. 4482 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4483 4484 // Otherwise, create a new declaration. If there is a previous 4485 // declaration of the same entity, the two will be linked via 4486 // PrevDecl. 4487 TagDecl *New; 4488 4489 if (Kind == TagDecl::TK_enum) { 4490 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4491 // enum X { A, B, C } D; D should chain to X. 4492 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4493 cast_or_null<EnumDecl>(PrevDecl)); 4494 // If this is an undefined enum, warn. 4495 if (TUK != TUK_Definition && !Invalid) { 4496 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4497 : diag::ext_forward_ref_enum; 4498 Diag(Loc, DK); 4499 } 4500 } else { 4501 // struct/union/class 4502 4503 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4504 // struct X { int A; } D; D should chain to X. 4505 if (getLangOptions().CPlusPlus) { 4506 // FIXME: Look for a way to use RecordDecl for simple structs. 4507 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4508 cast_or_null<CXXRecordDecl>(PrevDecl)); 4509 4510 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4511 StdBadAlloc = cast<CXXRecordDecl>(New); 4512 } else 4513 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4514 cast_or_null<RecordDecl>(PrevDecl)); 4515 } 4516 4517 if (Kind != TagDecl::TK_enum) { 4518 // Handle #pragma pack: if the #pragma pack stack has non-default 4519 // alignment, make up a packed attribute for this decl. These 4520 // attributes are checked when the ASTContext lays out the 4521 // structure. 4522 // 4523 // It is important for implementing the correct semantics that this 4524 // happen here (in act on tag decl). The #pragma pack stack is 4525 // maintained as a result of parser callbacks which can occur at 4526 // many points during the parsing of a struct declaration (because 4527 // the #pragma tokens are effectively skipped over during the 4528 // parsing of the struct). 4529 if (unsigned Alignment = getPragmaPackAlignment()) 4530 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4531 } 4532 4533 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4534 // C++ [dcl.typedef]p3: 4535 // [...] Similarly, in a given scope, a class or enumeration 4536 // shall not be declared with the same name as a typedef-name 4537 // that is declared in that scope and refers to a type other 4538 // than the class or enumeration itself. 4539 LookupResult Lookup; 4540 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4541 TypedefDecl *PrevTypedef = 0; 4542 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4543 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4544 4545 NamedDecl *PrevTypedefNamed = PrevTypedef; 4546 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4547 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4548 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4549 Diag(Loc, diag::err_tag_definition_of_typedef) 4550 << Context.getTypeDeclType(New) 4551 << PrevTypedef->getUnderlyingType(); 4552 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4553 Invalid = true; 4554 } 4555 } 4556 4557 // If this is a specialization of a member class (of a class template), 4558 // check the specialization. 4559 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4560 Invalid = true; 4561 4562 if (Invalid) 4563 New->setInvalidDecl(); 4564 4565 if (Attr) 4566 ProcessDeclAttributeList(S, New, Attr); 4567 4568 // If we're declaring or defining a tag in function prototype scope 4569 // in C, note that this type can only be used within the function. 4570 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4571 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4572 4573 // Set the lexical context. If the tag has a C++ scope specifier, the 4574 // lexical context will be different from the semantic context. 4575 New->setLexicalDeclContext(CurContext); 4576 4577 // Mark this as a friend decl if applicable. 4578 if (TUK == TUK_Friend) 4579 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4580 4581 // Set the access specifier. 4582 if (!Invalid && TUK != TUK_Friend) 4583 SetMemberAccessSpecifier(New, PrevDecl, AS); 4584 4585 if (TUK == TUK_Definition) 4586 New->startDefinition(); 4587 4588 // If this has an identifier, add it to the scope stack. 4589 if (TUK == TUK_Friend) { 4590 // We might be replacing an existing declaration in the lookup tables; 4591 // if so, borrow its access specifier. 4592 if (PrevDecl) 4593 New->setAccess(PrevDecl->getAccess()); 4594 4595 // Friend tag decls are visible in fairly strange ways. 4596 if (!CurContext->isDependentContext()) { 4597 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4598 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4599 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4600 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4601 } 4602 } else if (Name) { 4603 S = getNonFieldDeclScope(S); 4604 PushOnScopeChains(New, S); 4605 } else { 4606 CurContext->addDecl(New); 4607 } 4608 4609 // If this is the C FILE type, notify the AST context. 4610 if (IdentifierInfo *II = New->getIdentifier()) 4611 if (!New->isInvalidDecl() && 4612 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4613 II->isStr("FILE")) 4614 Context.setFILEDecl(New); 4615 4616 OwnedDecl = true; 4617 return DeclPtrTy::make(New); 4618} 4619 4620void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4621 AdjustDeclIfTemplate(TagD); 4622 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4623 4624 // Enter the tag context. 4625 PushDeclContext(S, Tag); 4626 4627 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4628 FieldCollector->StartClass(); 4629 4630 if (Record->getIdentifier()) { 4631 // C++ [class]p2: 4632 // [...] The class-name is also inserted into the scope of the 4633 // class itself; this is known as the injected-class-name. For 4634 // purposes of access checking, the injected-class-name is treated 4635 // as if it were a public member name. 4636 CXXRecordDecl *InjectedClassName 4637 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4638 CurContext, Record->getLocation(), 4639 Record->getIdentifier(), 4640 Record->getTagKeywordLoc(), 4641 Record); 4642 InjectedClassName->setImplicit(); 4643 InjectedClassName->setAccess(AS_public); 4644 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4645 InjectedClassName->setDescribedClassTemplate(Template); 4646 PushOnScopeChains(InjectedClassName, S); 4647 assert(InjectedClassName->isInjectedClassName() && 4648 "Broken injected-class-name"); 4649 } 4650 } 4651} 4652 4653void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4654 SourceLocation RBraceLoc) { 4655 AdjustDeclIfTemplate(TagD); 4656 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4657 Tag->setRBraceLoc(RBraceLoc); 4658 4659 if (isa<CXXRecordDecl>(Tag)) 4660 FieldCollector->FinishClass(); 4661 4662 // Exit this scope of this tag's definition. 4663 PopDeclContext(); 4664 4665 // Notify the consumer that we've defined a tag. 4666 Consumer.HandleTagDeclDefinition(Tag); 4667} 4668 4669// Note that FieldName may be null for anonymous bitfields. 4670bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4671 QualType FieldTy, const Expr *BitWidth, 4672 bool *ZeroWidth) { 4673 // Default to true; that shouldn't confuse checks for emptiness 4674 if (ZeroWidth) 4675 *ZeroWidth = true; 4676 4677 // C99 6.7.2.1p4 - verify the field type. 4678 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4679 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4680 // Handle incomplete types with specific error. 4681 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4682 return true; 4683 if (FieldName) 4684 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4685 << FieldName << FieldTy << BitWidth->getSourceRange(); 4686 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4687 << FieldTy << BitWidth->getSourceRange(); 4688 } 4689 4690 // If the bit-width is type- or value-dependent, don't try to check 4691 // it now. 4692 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4693 return false; 4694 4695 llvm::APSInt Value; 4696 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4697 return true; 4698 4699 if (Value != 0 && ZeroWidth) 4700 *ZeroWidth = false; 4701 4702 // Zero-width bitfield is ok for anonymous field. 4703 if (Value == 0 && FieldName) 4704 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4705 4706 if (Value.isSigned() && Value.isNegative()) { 4707 if (FieldName) 4708 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4709 << FieldName << Value.toString(10); 4710 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4711 << Value.toString(10); 4712 } 4713 4714 if (!FieldTy->isDependentType()) { 4715 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4716 if (Value.getZExtValue() > TypeSize) { 4717 if (FieldName) 4718 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4719 << FieldName << (unsigned)TypeSize; 4720 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4721 << (unsigned)TypeSize; 4722 } 4723 } 4724 4725 return false; 4726} 4727 4728/// ActOnField - Each field of a struct/union/class is passed into this in order 4729/// to create a FieldDecl object for it. 4730Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4731 SourceLocation DeclStart, 4732 Declarator &D, ExprTy *BitfieldWidth) { 4733 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4734 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4735 AS_public); 4736 return DeclPtrTy::make(Res); 4737} 4738 4739/// HandleField - Analyze a field of a C struct or a C++ data member. 4740/// 4741FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4742 SourceLocation DeclStart, 4743 Declarator &D, Expr *BitWidth, 4744 AccessSpecifier AS) { 4745 IdentifierInfo *II = D.getIdentifier(); 4746 SourceLocation Loc = DeclStart; 4747 if (II) Loc = D.getIdentifierLoc(); 4748 4749 DeclaratorInfo *DInfo = 0; 4750 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4751 if (getLangOptions().CPlusPlus) 4752 CheckExtraCXXDefaultArguments(D); 4753 4754 DiagnoseFunctionSpecifiers(D); 4755 4756 if (D.getDeclSpec().isThreadSpecified()) 4757 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4758 4759 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4760 4761 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4762 // Maybe we will complain about the shadowed template parameter. 4763 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4764 // Just pretend that we didn't see the previous declaration. 4765 PrevDecl = 0; 4766 } 4767 4768 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4769 PrevDecl = 0; 4770 4771 bool Mutable 4772 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4773 SourceLocation TSSL = D.getSourceRange().getBegin(); 4774 FieldDecl *NewFD 4775 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4776 AS, PrevDecl, &D); 4777 if (NewFD->isInvalidDecl() && PrevDecl) { 4778 // Don't introduce NewFD into scope; there's already something 4779 // with the same name in the same scope. 4780 } else if (II) { 4781 PushOnScopeChains(NewFD, S); 4782 } else 4783 Record->addDecl(NewFD); 4784 4785 return NewFD; 4786} 4787 4788/// \brief Build a new FieldDecl and check its well-formedness. 4789/// 4790/// This routine builds a new FieldDecl given the fields name, type, 4791/// record, etc. \p PrevDecl should refer to any previous declaration 4792/// with the same name and in the same scope as the field to be 4793/// created. 4794/// 4795/// \returns a new FieldDecl. 4796/// 4797/// \todo The Declarator argument is a hack. It will be removed once 4798FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4799 DeclaratorInfo *DInfo, 4800 RecordDecl *Record, SourceLocation Loc, 4801 bool Mutable, Expr *BitWidth, 4802 SourceLocation TSSL, 4803 AccessSpecifier AS, NamedDecl *PrevDecl, 4804 Declarator *D) { 4805 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4806 bool InvalidDecl = false; 4807 if (D) InvalidDecl = D->isInvalidType(); 4808 4809 // If we receive a broken type, recover by assuming 'int' and 4810 // marking this declaration as invalid. 4811 if (T.isNull()) { 4812 InvalidDecl = true; 4813 T = Context.IntTy; 4814 } 4815 4816 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4817 // than a variably modified type. 4818 if (T->isVariablyModifiedType()) { 4819 bool SizeIsNegative; 4820 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4821 SizeIsNegative); 4822 if (!FixedTy.isNull()) { 4823 Diag(Loc, diag::warn_illegal_constant_array_size); 4824 T = FixedTy; 4825 } else { 4826 if (SizeIsNegative) 4827 Diag(Loc, diag::err_typecheck_negative_array_size); 4828 else 4829 Diag(Loc, diag::err_typecheck_field_variable_size); 4830 InvalidDecl = true; 4831 } 4832 } 4833 4834 // Fields can not have abstract class types 4835 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4836 AbstractFieldType)) 4837 InvalidDecl = true; 4838 4839 bool ZeroWidth = false; 4840 // If this is declared as a bit-field, check the bit-field. 4841 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4842 InvalidDecl = true; 4843 DeleteExpr(BitWidth); 4844 BitWidth = 0; 4845 ZeroWidth = false; 4846 } 4847 4848 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4849 BitWidth, Mutable); 4850 if (InvalidDecl) 4851 NewFD->setInvalidDecl(); 4852 4853 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4854 Diag(Loc, diag::err_duplicate_member) << II; 4855 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4856 NewFD->setInvalidDecl(); 4857 } 4858 4859 if (getLangOptions().CPlusPlus) { 4860 QualType EltTy = Context.getBaseElementType(T); 4861 4862 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4863 4864 if (!T->isPODType()) 4865 CXXRecord->setPOD(false); 4866 if (!ZeroWidth) 4867 CXXRecord->setEmpty(false); 4868 4869 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4870 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4871 4872 if (!RDecl->hasTrivialConstructor()) 4873 CXXRecord->setHasTrivialConstructor(false); 4874 if (!RDecl->hasTrivialCopyConstructor()) 4875 CXXRecord->setHasTrivialCopyConstructor(false); 4876 if (!RDecl->hasTrivialCopyAssignment()) 4877 CXXRecord->setHasTrivialCopyAssignment(false); 4878 if (!RDecl->hasTrivialDestructor()) 4879 CXXRecord->setHasTrivialDestructor(false); 4880 4881 // C++ 9.5p1: An object of a class with a non-trivial 4882 // constructor, a non-trivial copy constructor, a non-trivial 4883 // destructor, or a non-trivial copy assignment operator 4884 // cannot be a member of a union, nor can an array of such 4885 // objects. 4886 // TODO: C++0x alters this restriction significantly. 4887 if (Record->isUnion()) { 4888 // We check for copy constructors before constructors 4889 // because otherwise we'll never get complaints about 4890 // copy constructors. 4891 4892 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4893 4894 CXXSpecialMember member; 4895 if (!RDecl->hasTrivialCopyConstructor()) 4896 member = CXXCopyConstructor; 4897 else if (!RDecl->hasTrivialConstructor()) 4898 member = CXXDefaultConstructor; 4899 else if (!RDecl->hasTrivialCopyAssignment()) 4900 member = CXXCopyAssignment; 4901 else if (!RDecl->hasTrivialDestructor()) 4902 member = CXXDestructor; 4903 else 4904 member = invalid; 4905 4906 if (member != invalid) { 4907 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4908 DiagnoseNontrivial(RT, member); 4909 NewFD->setInvalidDecl(); 4910 } 4911 } 4912 } 4913 } 4914 4915 // FIXME: We need to pass in the attributes given an AST 4916 // representation, not a parser representation. 4917 if (D) 4918 // FIXME: What to pass instead of TUScope? 4919 ProcessDeclAttributes(TUScope, NewFD, *D); 4920 4921 if (T.isObjCGCWeak()) 4922 Diag(Loc, diag::warn_attribute_weak_on_field); 4923 4924 NewFD->setAccess(AS); 4925 4926 // C++ [dcl.init.aggr]p1: 4927 // An aggregate is an array or a class (clause 9) with [...] no 4928 // private or protected non-static data members (clause 11). 4929 // A POD must be an aggregate. 4930 if (getLangOptions().CPlusPlus && 4931 (AS == AS_private || AS == AS_protected)) { 4932 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4933 CXXRecord->setAggregate(false); 4934 CXXRecord->setPOD(false); 4935 } 4936 4937 return NewFD; 4938} 4939 4940/// DiagnoseNontrivial - Given that a class has a non-trivial 4941/// special member, figure out why. 4942void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4943 QualType QT(T, 0U); 4944 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4945 4946 // Check whether the member was user-declared. 4947 switch (member) { 4948 case CXXDefaultConstructor: 4949 if (RD->hasUserDeclaredConstructor()) { 4950 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4951 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce; ++ci) 4952 if (!ci->isImplicitlyDefined(Context)) { 4953 SourceLocation CtorLoc = ci->getLocation(); 4954 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4955 return; 4956 } 4957 4958 assert(0 && "found no user-declared constructors"); 4959 return; 4960 } 4961 break; 4962 4963 case CXXCopyConstructor: 4964 if (RD->hasUserDeclaredCopyConstructor()) { 4965 SourceLocation CtorLoc = 4966 RD->getCopyConstructor(Context, 0)->getLocation(); 4967 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4968 return; 4969 } 4970 break; 4971 4972 case CXXCopyAssignment: 4973 if (RD->hasUserDeclaredCopyAssignment()) { 4974 // FIXME: this should use the location of the copy 4975 // assignment, not the type. 4976 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4977 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4978 return; 4979 } 4980 break; 4981 4982 case CXXDestructor: 4983 if (RD->hasUserDeclaredDestructor()) { 4984 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4985 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4986 return; 4987 } 4988 break; 4989 } 4990 4991 typedef CXXRecordDecl::base_class_iterator base_iter; 4992 4993 // Virtual bases and members inhibit trivial copying/construction, 4994 // but not trivial destruction. 4995 if (member != CXXDestructor) { 4996 // Check for virtual bases. vbases includes indirect virtual bases, 4997 // so we just iterate through the direct bases. 4998 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 4999 if (bi->isVirtual()) { 5000 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5001 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5002 return; 5003 } 5004 5005 // Check for virtual methods. 5006 typedef CXXRecordDecl::method_iterator meth_iter; 5007 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5008 ++mi) { 5009 if (mi->isVirtual()) { 5010 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5011 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5012 return; 5013 } 5014 } 5015 } 5016 5017 bool (CXXRecordDecl::*hasTrivial)() const; 5018 switch (member) { 5019 case CXXDefaultConstructor: 5020 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5021 case CXXCopyConstructor: 5022 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5023 case CXXCopyAssignment: 5024 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5025 case CXXDestructor: 5026 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5027 default: 5028 assert(0 && "unexpected special member"); return; 5029 } 5030 5031 // Check for nontrivial bases (and recurse). 5032 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5033 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5034 assert(BaseRT); 5035 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5036 if (!(BaseRecTy->*hasTrivial)()) { 5037 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5038 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5039 DiagnoseNontrivial(BaseRT, member); 5040 return; 5041 } 5042 } 5043 5044 // Check for nontrivial members (and recurse). 5045 typedef RecordDecl::field_iterator field_iter; 5046 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5047 ++fi) { 5048 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5049 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5050 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5051 5052 if (!(EltRD->*hasTrivial)()) { 5053 SourceLocation FLoc = (*fi)->getLocation(); 5054 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5055 DiagnoseNontrivial(EltRT, member); 5056 return; 5057 } 5058 } 5059 } 5060 5061 assert(0 && "found no explanation for non-trivial member"); 5062} 5063 5064/// TranslateIvarVisibility - Translate visibility from a token ID to an 5065/// AST enum value. 5066static ObjCIvarDecl::AccessControl 5067TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5068 switch (ivarVisibility) { 5069 default: assert(0 && "Unknown visitibility kind"); 5070 case tok::objc_private: return ObjCIvarDecl::Private; 5071 case tok::objc_public: return ObjCIvarDecl::Public; 5072 case tok::objc_protected: return ObjCIvarDecl::Protected; 5073 case tok::objc_package: return ObjCIvarDecl::Package; 5074 } 5075} 5076 5077/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5078/// in order to create an IvarDecl object for it. 5079Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5080 SourceLocation DeclStart, 5081 DeclPtrTy IntfDecl, 5082 Declarator &D, ExprTy *BitfieldWidth, 5083 tok::ObjCKeywordKind Visibility) { 5084 5085 IdentifierInfo *II = D.getIdentifier(); 5086 Expr *BitWidth = (Expr*)BitfieldWidth; 5087 SourceLocation Loc = DeclStart; 5088 if (II) Loc = D.getIdentifierLoc(); 5089 5090 // FIXME: Unnamed fields can be handled in various different ways, for 5091 // example, unnamed unions inject all members into the struct namespace! 5092 5093 DeclaratorInfo *DInfo = 0; 5094 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5095 5096 if (BitWidth) { 5097 // 6.7.2.1p3, 6.7.2.1p4 5098 if (VerifyBitField(Loc, II, T, BitWidth)) { 5099 D.setInvalidType(); 5100 DeleteExpr(BitWidth); 5101 BitWidth = 0; 5102 } 5103 } else { 5104 // Not a bitfield. 5105 5106 // validate II. 5107 5108 } 5109 5110 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5111 // than a variably modified type. 5112 if (T->isVariablyModifiedType()) { 5113 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5114 D.setInvalidType(); 5115 } 5116 5117 // Get the visibility (access control) for this ivar. 5118 ObjCIvarDecl::AccessControl ac = 5119 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5120 : ObjCIvarDecl::None; 5121 // Must set ivar's DeclContext to its enclosing interface. 5122 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5123 DeclContext *EnclosingContext; 5124 if (ObjCImplementationDecl *IMPDecl = 5125 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5126 // Case of ivar declared in an implementation. Context is that of its class. 5127 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5128 assert(IDecl && "No class- ActOnIvar"); 5129 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5130 } else 5131 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5132 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5133 5134 // Construct the decl. 5135 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5136 EnclosingContext, Loc, II, T, 5137 DInfo, ac, (Expr *)BitfieldWidth); 5138 5139 if (II) { 5140 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5141 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5142 && !isa<TagDecl>(PrevDecl)) { 5143 Diag(Loc, diag::err_duplicate_member) << II; 5144 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5145 NewID->setInvalidDecl(); 5146 } 5147 } 5148 5149 // Process attributes attached to the ivar. 5150 ProcessDeclAttributes(S, NewID, D); 5151 5152 if (D.isInvalidType()) 5153 NewID->setInvalidDecl(); 5154 5155 if (II) { 5156 // FIXME: When interfaces are DeclContexts, we'll need to add 5157 // these to the interface. 5158 S->AddDecl(DeclPtrTy::make(NewID)); 5159 IdResolver.AddDecl(NewID); 5160 } 5161 5162 return DeclPtrTy::make(NewID); 5163} 5164 5165void Sema::ActOnFields(Scope* S, 5166 SourceLocation RecLoc, DeclPtrTy RecDecl, 5167 DeclPtrTy *Fields, unsigned NumFields, 5168 SourceLocation LBrac, SourceLocation RBrac, 5169 AttributeList *Attr) { 5170 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5171 assert(EnclosingDecl && "missing record or interface decl"); 5172 5173 // If the decl this is being inserted into is invalid, then it may be a 5174 // redeclaration or some other bogus case. Don't try to add fields to it. 5175 if (EnclosingDecl->isInvalidDecl()) { 5176 // FIXME: Deallocate fields? 5177 return; 5178 } 5179 5180 5181 // Verify that all the fields are okay. 5182 unsigned NumNamedMembers = 0; 5183 llvm::SmallVector<FieldDecl*, 32> RecFields; 5184 5185 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5186 for (unsigned i = 0; i != NumFields; ++i) { 5187 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5188 5189 // Get the type for the field. 5190 Type *FDTy = FD->getType().getTypePtr(); 5191 5192 if (!FD->isAnonymousStructOrUnion()) { 5193 // Remember all fields written by the user. 5194 RecFields.push_back(FD); 5195 } 5196 5197 // If the field is already invalid for some reason, don't emit more 5198 // diagnostics about it. 5199 if (FD->isInvalidDecl()) 5200 continue; 5201 5202 // C99 6.7.2.1p2: 5203 // A structure or union shall not contain a member with 5204 // incomplete or function type (hence, a structure shall not 5205 // contain an instance of itself, but may contain a pointer to 5206 // an instance of itself), except that the last member of a 5207 // structure with more than one named member may have incomplete 5208 // array type; such a structure (and any union containing, 5209 // possibly recursively, a member that is such a structure) 5210 // shall not be a member of a structure or an element of an 5211 // array. 5212 if (FDTy->isFunctionType()) { 5213 // Field declared as a function. 5214 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5215 << FD->getDeclName(); 5216 FD->setInvalidDecl(); 5217 EnclosingDecl->setInvalidDecl(); 5218 continue; 5219 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5220 Record && Record->isStruct()) { 5221 // Flexible array member. 5222 if (NumNamedMembers < 1) { 5223 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5224 << FD->getDeclName(); 5225 FD->setInvalidDecl(); 5226 EnclosingDecl->setInvalidDecl(); 5227 continue; 5228 } 5229 // Okay, we have a legal flexible array member at the end of the struct. 5230 if (Record) 5231 Record->setHasFlexibleArrayMember(true); 5232 } else if (!FDTy->isDependentType() && 5233 RequireCompleteType(FD->getLocation(), FD->getType(), 5234 diag::err_field_incomplete)) { 5235 // Incomplete type 5236 FD->setInvalidDecl(); 5237 EnclosingDecl->setInvalidDecl(); 5238 continue; 5239 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5240 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5241 // If this is a member of a union, then entire union becomes "flexible". 5242 if (Record && Record->isUnion()) { 5243 Record->setHasFlexibleArrayMember(true); 5244 } else { 5245 // If this is a struct/class and this is not the last element, reject 5246 // it. Note that GCC supports variable sized arrays in the middle of 5247 // structures. 5248 if (i != NumFields-1) 5249 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5250 << FD->getDeclName() << FD->getType(); 5251 else { 5252 // We support flexible arrays at the end of structs in 5253 // other structs as an extension. 5254 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5255 << FD->getDeclName(); 5256 if (Record) 5257 Record->setHasFlexibleArrayMember(true); 5258 } 5259 } 5260 } 5261 if (Record && FDTTy->getDecl()->hasObjectMember()) 5262 Record->setHasObjectMember(true); 5263 } else if (FDTy->isObjCInterfaceType()) { 5264 /// A field cannot be an Objective-c object 5265 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5266 FD->setInvalidDecl(); 5267 EnclosingDecl->setInvalidDecl(); 5268 continue; 5269 } else if (getLangOptions().ObjC1 && 5270 getLangOptions().getGCMode() != LangOptions::NonGC && 5271 Record && 5272 (FD->getType()->isObjCObjectPointerType() || 5273 FD->getType().isObjCGCStrong())) 5274 Record->setHasObjectMember(true); 5275 // Keep track of the number of named members. 5276 if (FD->getIdentifier()) 5277 ++NumNamedMembers; 5278 } 5279 5280 // Okay, we successfully defined 'Record'. 5281 if (Record) { 5282 Record->completeDefinition(Context); 5283 } else { 5284 ObjCIvarDecl **ClsFields = 5285 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5286 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5287 ID->setIVarList(ClsFields, RecFields.size(), Context); 5288 ID->setLocEnd(RBrac); 5289 // Add ivar's to class's DeclContext. 5290 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5291 ClsFields[i]->setLexicalDeclContext(ID); 5292 ID->addDecl(ClsFields[i]); 5293 } 5294 // Must enforce the rule that ivars in the base classes may not be 5295 // duplicates. 5296 if (ID->getSuperClass()) { 5297 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5298 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5299 ObjCIvarDecl* Ivar = (*IVI); 5300 5301 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5302 ObjCIvarDecl* prevIvar = 5303 ID->getSuperClass()->lookupInstanceVariable(II); 5304 if (prevIvar) { 5305 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5306 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5307 } 5308 } 5309 } 5310 } 5311 } else if (ObjCImplementationDecl *IMPDecl = 5312 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5313 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5314 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5315 // Ivar declared in @implementation never belongs to the implementation. 5316 // Only it is in implementation's lexical context. 5317 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5318 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5319 } 5320 } 5321 5322 if (Attr) 5323 ProcessDeclAttributeList(S, Record, Attr); 5324} 5325 5326EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5327 EnumConstantDecl *LastEnumConst, 5328 SourceLocation IdLoc, 5329 IdentifierInfo *Id, 5330 ExprArg val) { 5331 Expr *Val = (Expr *)val.get(); 5332 5333 llvm::APSInt EnumVal(32); 5334 QualType EltTy; 5335 if (Val && !Val->isTypeDependent()) { 5336 // Make sure to promote the operand type to int. 5337 UsualUnaryConversions(Val); 5338 if (Val != val.get()) { 5339 val.release(); 5340 val = Val; 5341 } 5342 5343 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5344 SourceLocation ExpLoc; 5345 if (!Val->isValueDependent() && 5346 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5347 Val = 0; 5348 } else { 5349 EltTy = Val->getType(); 5350 } 5351 } 5352 5353 if (!Val) { 5354 if (LastEnumConst) { 5355 // Assign the last value + 1. 5356 EnumVal = LastEnumConst->getInitVal(); 5357 ++EnumVal; 5358 5359 // Check for overflow on increment. 5360 if (EnumVal < LastEnumConst->getInitVal()) 5361 Diag(IdLoc, diag::warn_enum_value_overflow); 5362 5363 EltTy = LastEnumConst->getType(); 5364 } else { 5365 // First value, set to zero. 5366 EltTy = Context.IntTy; 5367 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5368 } 5369 } 5370 5371 val.release(); 5372 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5373 Val, EnumVal); 5374} 5375 5376 5377Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5378 DeclPtrTy lastEnumConst, 5379 SourceLocation IdLoc, 5380 IdentifierInfo *Id, 5381 SourceLocation EqualLoc, ExprTy *val) { 5382 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5383 EnumConstantDecl *LastEnumConst = 5384 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5385 Expr *Val = static_cast<Expr*>(val); 5386 5387 // The scope passed in may not be a decl scope. Zip up the scope tree until 5388 // we find one that is. 5389 S = getNonFieldDeclScope(S); 5390 5391 // Verify that there isn't already something declared with this name in this 5392 // scope. 5393 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5394 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5395 // Maybe we will complain about the shadowed template parameter. 5396 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5397 // Just pretend that we didn't see the previous declaration. 5398 PrevDecl = 0; 5399 } 5400 5401 if (PrevDecl) { 5402 // When in C++, we may get a TagDecl with the same name; in this case the 5403 // enum constant will 'hide' the tag. 5404 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5405 "Received TagDecl when not in C++!"); 5406 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5407 if (isa<EnumConstantDecl>(PrevDecl)) 5408 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5409 else 5410 Diag(IdLoc, diag::err_redefinition) << Id; 5411 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5412 if (Val) Val->Destroy(Context); 5413 return DeclPtrTy(); 5414 } 5415 } 5416 5417 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5418 IdLoc, Id, Owned(Val)); 5419 5420 // Register this decl in the current scope stack. 5421 if (New) 5422 PushOnScopeChains(New, S); 5423 5424 return DeclPtrTy::make(New); 5425} 5426 5427void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5428 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5429 DeclPtrTy *Elements, unsigned NumElements, 5430 Scope *S, AttributeList *Attr) { 5431 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5432 QualType EnumType = Context.getTypeDeclType(Enum); 5433 5434 if (Attr) 5435 ProcessDeclAttributeList(S, Enum, Attr); 5436 5437 // TODO: If the result value doesn't fit in an int, it must be a long or long 5438 // long value. ISO C does not support this, but GCC does as an extension, 5439 // emit a warning. 5440 unsigned IntWidth = Context.Target.getIntWidth(); 5441 unsigned CharWidth = Context.Target.getCharWidth(); 5442 unsigned ShortWidth = Context.Target.getShortWidth(); 5443 5444 // Verify that all the values are okay, compute the size of the values, and 5445 // reverse the list. 5446 unsigned NumNegativeBits = 0; 5447 unsigned NumPositiveBits = 0; 5448 5449 // Keep track of whether all elements have type int. 5450 bool AllElementsInt = true; 5451 5452 for (unsigned i = 0; i != NumElements; ++i) { 5453 EnumConstantDecl *ECD = 5454 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5455 if (!ECD) continue; // Already issued a diagnostic. 5456 5457 // If the enum value doesn't fit in an int, emit an extension warning. 5458 const llvm::APSInt &InitVal = ECD->getInitVal(); 5459 assert(InitVal.getBitWidth() >= IntWidth && 5460 "Should have promoted value to int"); 5461 if (InitVal.getBitWidth() > IntWidth) { 5462 llvm::APSInt V(InitVal); 5463 V.trunc(IntWidth); 5464 V.extend(InitVal.getBitWidth()); 5465 if (V != InitVal) 5466 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5467 << InitVal.toString(10); 5468 } 5469 5470 // Keep track of the size of positive and negative values. 5471 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5472 NumPositiveBits = std::max(NumPositiveBits, 5473 (unsigned)InitVal.getActiveBits()); 5474 else 5475 NumNegativeBits = std::max(NumNegativeBits, 5476 (unsigned)InitVal.getMinSignedBits()); 5477 5478 // Keep track of whether every enum element has type int (very commmon). 5479 if (AllElementsInt) 5480 AllElementsInt = ECD->getType() == Context.IntTy; 5481 } 5482 5483 // Figure out the type that should be used for this enum. 5484 // FIXME: Support -fshort-enums. 5485 QualType BestType; 5486 unsigned BestWidth; 5487 5488 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5489 5490 if (NumNegativeBits) { 5491 // If there is a negative value, figure out the smallest integer type (of 5492 // int/long/longlong) that fits. 5493 // If it's packed, check also if it fits a char or a short. 5494 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5495 BestType = Context.SignedCharTy; 5496 BestWidth = CharWidth; 5497 } else if (Packed && NumNegativeBits <= ShortWidth && 5498 NumPositiveBits < ShortWidth) { 5499 BestType = Context.ShortTy; 5500 BestWidth = ShortWidth; 5501 } 5502 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5503 BestType = Context.IntTy; 5504 BestWidth = IntWidth; 5505 } else { 5506 BestWidth = Context.Target.getLongWidth(); 5507 5508 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5509 BestType = Context.LongTy; 5510 else { 5511 BestWidth = Context.Target.getLongLongWidth(); 5512 5513 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5514 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5515 BestType = Context.LongLongTy; 5516 } 5517 } 5518 } else { 5519 // If there is no negative value, figure out which of uint, ulong, ulonglong 5520 // fits. 5521 // If it's packed, check also if it fits a char or a short. 5522 if (Packed && NumPositiveBits <= CharWidth) { 5523 BestType = Context.UnsignedCharTy; 5524 BestWidth = CharWidth; 5525 } else if (Packed && NumPositiveBits <= ShortWidth) { 5526 BestType = Context.UnsignedShortTy; 5527 BestWidth = ShortWidth; 5528 } 5529 else if (NumPositiveBits <= IntWidth) { 5530 BestType = Context.UnsignedIntTy; 5531 BestWidth = IntWidth; 5532 } else if (NumPositiveBits <= 5533 (BestWidth = Context.Target.getLongWidth())) { 5534 BestType = Context.UnsignedLongTy; 5535 } else { 5536 BestWidth = Context.Target.getLongLongWidth(); 5537 assert(NumPositiveBits <= BestWidth && 5538 "How could an initializer get larger than ULL?"); 5539 BestType = Context.UnsignedLongLongTy; 5540 } 5541 } 5542 5543 // Loop over all of the enumerator constants, changing their types to match 5544 // the type of the enum if needed. 5545 for (unsigned i = 0; i != NumElements; ++i) { 5546 EnumConstantDecl *ECD = 5547 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5548 if (!ECD) continue; // Already issued a diagnostic. 5549 5550 // Standard C says the enumerators have int type, but we allow, as an 5551 // extension, the enumerators to be larger than int size. If each 5552 // enumerator value fits in an int, type it as an int, otherwise type it the 5553 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5554 // that X has type 'int', not 'unsigned'. 5555 if (ECD->getType() == Context.IntTy) { 5556 // Make sure the init value is signed. 5557 llvm::APSInt IV = ECD->getInitVal(); 5558 IV.setIsSigned(true); 5559 ECD->setInitVal(IV); 5560 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; // Already int type. 5567 } 5568 5569 // Determine whether the value fits into an int. 5570 llvm::APSInt InitVal = ECD->getInitVal(); 5571 bool FitsInInt; 5572 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5573 FitsInInt = InitVal.getActiveBits() < IntWidth; 5574 else 5575 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5576 5577 // If it fits into an integer type, force it. Otherwise force it to match 5578 // the enum decl type. 5579 QualType NewTy; 5580 unsigned NewWidth; 5581 bool NewSign; 5582 if (FitsInInt) { 5583 NewTy = Context.IntTy; 5584 NewWidth = IntWidth; 5585 NewSign = true; 5586 } else if (ECD->getType() == BestType) { 5587 // Already the right type! 5588 if (getLangOptions().CPlusPlus) 5589 // C++ [dcl.enum]p4: Following the closing brace of an 5590 // enum-specifier, each enumerator has the type of its 5591 // enumeration. 5592 ECD->setType(EnumType); 5593 continue; 5594 } else { 5595 NewTy = BestType; 5596 NewWidth = BestWidth; 5597 NewSign = BestType->isSignedIntegerType(); 5598 } 5599 5600 // Adjust the APSInt value. 5601 InitVal.extOrTrunc(NewWidth); 5602 InitVal.setIsSigned(NewSign); 5603 ECD->setInitVal(InitVal); 5604 5605 // Adjust the Expr initializer and type. 5606 if (ECD->getInitExpr()) 5607 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5608 CastExpr::CK_IntegralCast, 5609 ECD->getInitExpr(), 5610 /*isLvalue=*/false)); 5611 if (getLangOptions().CPlusPlus) 5612 // C++ [dcl.enum]p4: Following the closing brace of an 5613 // enum-specifier, each enumerator has the type of its 5614 // enumeration. 5615 ECD->setType(EnumType); 5616 else 5617 ECD->setType(NewTy); 5618 } 5619 5620 Enum->completeDefinition(Context, BestType); 5621} 5622 5623Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5624 ExprArg expr) { 5625 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5626 5627 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5628 Loc, AsmString); 5629 CurContext->addDecl(New); 5630 return DeclPtrTy::make(New); 5631} 5632 5633void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5634 SourceLocation PragmaLoc, 5635 SourceLocation NameLoc) { 5636 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5637 5638 if (PrevDecl) { 5639 PrevDecl->addAttr(::new (Context) WeakAttr()); 5640 } else { 5641 (void)WeakUndeclaredIdentifiers.insert( 5642 std::pair<IdentifierInfo*,WeakInfo> 5643 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5644 } 5645} 5646 5647void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5648 IdentifierInfo* AliasName, 5649 SourceLocation PragmaLoc, 5650 SourceLocation NameLoc, 5651 SourceLocation AliasNameLoc) { 5652 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5653 WeakInfo W = WeakInfo(Name, NameLoc); 5654 5655 if (PrevDecl) { 5656 if (!PrevDecl->hasAttr<AliasAttr>()) 5657 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5658 DeclApplyPragmaWeak(TUScope, ND, W); 5659 } else { 5660 (void)WeakUndeclaredIdentifiers.insert( 5661 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5662 } 5663} 5664