SemaDecl.cpp revision c79209789205c9de5fcc7aedfd6308057d40b618
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/Parse/Template.h" 28#include "clang/Basic/PartialDiagnostic.h" 29#include "clang/Basic/SourceManager.h" 30#include "clang/Basic/TargetInfo.h" 31// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 32#include "clang/Lex/Preprocessor.h" 33#include "clang/Lex/HeaderSearch.h" 34#include "llvm/ADT/BitVector.h" 35#include "llvm/ADT/STLExtras.h" 36#include <algorithm> 37#include <cstring> 38#include <functional> 39#include <queue> 40using namespace clang; 41 42/// getDeclName - Return a pretty name for the specified decl if possible, or 43/// an empty string if not. This is used for pretty crash reporting. 44std::string Sema::getDeclName(DeclPtrTy d) { 45 Decl *D = d.getAs<Decl>(); 46 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 47 return DN->getQualifiedNameAsString(); 48 return ""; 49} 50 51Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 52 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 53} 54 55/// \brief If the identifier refers to a type name within this scope, 56/// return the declaration of that type. 57/// 58/// This routine performs ordinary name lookup of the identifier II 59/// within the given scope, with optional C++ scope specifier SS, to 60/// determine whether the name refers to a type. If so, returns an 61/// opaque pointer (actually a QualType) corresponding to that 62/// type. Otherwise, returns NULL. 63/// 64/// If name lookup results in an ambiguity, this routine will complain 65/// and then return NULL. 66Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 67 Scope *S, const CXXScopeSpec *SS, 68 bool isClassName) { 69 // C++ [temp.res]p3: 70 // A qualified-id that refers to a type and in which the 71 // nested-name-specifier depends on a template-parameter (14.6.2) 72 // shall be prefixed by the keyword typename to indicate that the 73 // qualified-id denotes a type, forming an 74 // elaborated-type-specifier (7.1.5.3). 75 // 76 // We therefore do not perform any name lookup if the result would 77 // refer to a member of an unknown specialization. 78 if (SS && isUnknownSpecialization(*SS)) { 79 if (!isClassName) 80 return 0; 81 82 // We know from the grammar that this name refers to a type, so build a 83 // TypenameType node to describe the type. 84 // FIXME: Record somewhere that this TypenameType node has no "typename" 85 // keyword associated with it. 86 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 87 II, SS->getRange()).getAsOpaquePtr(); 88 } 89 90 LookupResult Result; 91 LookupParsedName(Result, S, SS, &II, LookupOrdinaryName, false, false); 92 93 NamedDecl *IIDecl = 0; 94 switch (Result.getKind()) { 95 case LookupResult::NotFound: 96 case LookupResult::FoundOverloaded: 97 return 0; 98 99 case LookupResult::Ambiguous: 100 // Recover from type-hiding ambiguities by hiding the type. We'll 101 // do the lookup again when looking for an object, and we can 102 // diagnose the error then. If we don't do this, then the error 103 // about hiding the type will be immediately followed by an error 104 // that only makes sense if the identifier was treated like a type. 105 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) 106 return 0; 107 108 // Look to see if we have a type anywhere in the list of results. 109 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 110 Res != ResEnd; ++Res) { 111 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 112 if (!IIDecl || 113 (*Res)->getLocation().getRawEncoding() < 114 IIDecl->getLocation().getRawEncoding()) 115 IIDecl = *Res; 116 } 117 } 118 119 if (!IIDecl) { 120 // None of the entities we found is a type, so there is no way 121 // to even assume that the result is a type. In this case, don't 122 // complain about the ambiguity. The parser will either try to 123 // perform this lookup again (e.g., as an object name), which 124 // will produce the ambiguity, or will complain that it expected 125 // a type name. 126 return 0; 127 } 128 129 // We found a type within the ambiguous lookup; diagnose the 130 // ambiguity and then return that type. This might be the right 131 // answer, or it might not be, but it suppresses any attempt to 132 // perform the name lookup again. 133 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 134 break; 135 136 case LookupResult::Found: 137 IIDecl = Result.getFoundDecl(); 138 break; 139 } 140 141 assert(IIDecl && "Didn't find decl"); 142 143 QualType T; 144 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 145 DiagnoseUseOfDecl(IIDecl, NameLoc); 146 147 // C++ [temp.local]p2: 148 // Within the scope of a class template specialization or 149 // partial specialization, when the injected-class-name is 150 // not followed by a <, it is equivalent to the 151 // injected-class-name followed by the template-argument s 152 // of the class template specialization or partial 153 // specialization enclosed in <>. 154 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 155 if (RD->isInjectedClassName()) 156 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 157 T = Template->getInjectedClassNameType(Context); 158 159 if (T.isNull()) 160 T = Context.getTypeDeclType(TD); 161 162 if (SS) 163 T = getQualifiedNameType(*SS, T); 164 165 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 166 DiagnoseUseOfDecl(IIDecl, NameLoc); 167 T = Context.getObjCInterfaceType(IDecl); 168 } else 169 return 0; 170 171 return T.getAsOpaquePtr(); 172} 173 174/// isTagName() - This method is called *for error recovery purposes only* 175/// to determine if the specified name is a valid tag name ("struct foo"). If 176/// so, this returns the TST for the tag corresponding to it (TST_enum, 177/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 178/// where the user forgot to specify the tag. 179DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 180 // Do a tag name lookup in this scope. 181 LookupResult R; 182 LookupName(R, S, &II, LookupTagName, false, false); 183 if (R.getKind() == LookupResult::Found) 184 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 185 switch (TD->getTagKind()) { 186 case TagDecl::TK_struct: return DeclSpec::TST_struct; 187 case TagDecl::TK_union: return DeclSpec::TST_union; 188 case TagDecl::TK_class: return DeclSpec::TST_class; 189 case TagDecl::TK_enum: return DeclSpec::TST_enum; 190 } 191 } 192 193 return DeclSpec::TST_unspecified; 194} 195 196bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 197 SourceLocation IILoc, 198 Scope *S, 199 const CXXScopeSpec *SS, 200 TypeTy *&SuggestedType) { 201 // We don't have anything to suggest (yet). 202 SuggestedType = 0; 203 204 // FIXME: Should we move the logic that tries to recover from a missing tag 205 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 206 207 if (!SS) 208 Diag(IILoc, diag::err_unknown_typename) << &II; 209 else if (DeclContext *DC = computeDeclContext(*SS, false)) 210 Diag(IILoc, diag::err_typename_nested_not_found) 211 << &II << DC << SS->getRange(); 212 else if (isDependentScopeSpecifier(*SS)) { 213 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 214 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 215 << SourceRange(SS->getRange().getBegin(), IILoc) 216 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 217 "typename "); 218 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 219 } else { 220 assert(SS && SS->isInvalid() && 221 "Invalid scope specifier has already been diagnosed"); 222 } 223 224 return true; 225} 226 227// Determines the context to return to after temporarily entering a 228// context. This depends in an unnecessarily complicated way on the 229// exact ordering of callbacks from the parser. 230DeclContext *Sema::getContainingDC(DeclContext *DC) { 231 232 // Functions defined inline within classes aren't parsed until we've 233 // finished parsing the top-level class, so the top-level class is 234 // the context we'll need to return to. 235 if (isa<FunctionDecl>(DC)) { 236 DC = DC->getLexicalParent(); 237 238 // A function not defined within a class will always return to its 239 // lexical context. 240 if (!isa<CXXRecordDecl>(DC)) 241 return DC; 242 243 // A C++ inline method/friend is parsed *after* the topmost class 244 // it was declared in is fully parsed ("complete"); the topmost 245 // class is the context we need to return to. 246 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 247 DC = RD; 248 249 // Return the declaration context of the topmost class the inline method is 250 // declared in. 251 return DC; 252 } 253 254 if (isa<ObjCMethodDecl>(DC)) 255 return Context.getTranslationUnitDecl(); 256 257 return DC->getLexicalParent(); 258} 259 260void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 261 assert(getContainingDC(DC) == CurContext && 262 "The next DeclContext should be lexically contained in the current one."); 263 CurContext = DC; 264 S->setEntity(DC); 265} 266 267void Sema::PopDeclContext() { 268 assert(CurContext && "DeclContext imbalance!"); 269 270 CurContext = getContainingDC(CurContext); 271} 272 273/// EnterDeclaratorContext - Used when we must lookup names in the context 274/// of a declarator's nested name specifier. 275void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 276 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 277 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 278 CurContext = DC; 279 assert(CurContext && "No context?"); 280 S->setEntity(CurContext); 281} 282 283void Sema::ExitDeclaratorContext(Scope *S) { 284 S->setEntity(PreDeclaratorDC); 285 PreDeclaratorDC = 0; 286 287 // Reset CurContext to the nearest enclosing context. 288 while (!S->getEntity() && S->getParent()) 289 S = S->getParent(); 290 CurContext = static_cast<DeclContext*>(S->getEntity()); 291 assert(CurContext && "No context?"); 292} 293 294/// \brief Determine whether we allow overloading of the function 295/// PrevDecl with another declaration. 296/// 297/// This routine determines whether overloading is possible, not 298/// whether some new function is actually an overload. It will return 299/// true in C++ (where we can always provide overloads) or, as an 300/// extension, in C when the previous function is already an 301/// overloaded function declaration or has the "overloadable" 302/// attribute. 303static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 304 if (Context.getLangOptions().CPlusPlus) 305 return true; 306 307 if (isa<OverloadedFunctionDecl>(PrevDecl)) 308 return true; 309 310 return PrevDecl->getAttr<OverloadableAttr>() != 0; 311} 312 313/// Add this decl to the scope shadowed decl chains. 314void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 315 // Move up the scope chain until we find the nearest enclosing 316 // non-transparent context. The declaration will be introduced into this 317 // scope. 318 while (S->getEntity() && 319 ((DeclContext *)S->getEntity())->isTransparentContext()) 320 S = S->getParent(); 321 322 // Add scoped declarations into their context, so that they can be 323 // found later. Declarations without a context won't be inserted 324 // into any context. 325 if (AddToContext) 326 CurContext->addDecl(D); 327 328 // Out-of-line function and variable definitions should not be pushed into 329 // scope. 330 if ((isa<FunctionTemplateDecl>(D) && 331 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 332 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 333 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 334 return; 335 336 // If this replaces anything in the current scope, 337 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 338 IEnd = IdResolver.end(); 339 for (; I != IEnd; ++I) { 340 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 341 S->RemoveDecl(DeclPtrTy::make(*I)); 342 IdResolver.RemoveDecl(*I); 343 344 // Should only need to replace one decl. 345 break; 346 } 347 } 348 349 S->AddDecl(DeclPtrTy::make(D)); 350 IdResolver.AddDecl(D); 351} 352 353bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 354 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 355 // Look inside the overload set to determine if any of the declarations 356 // are in scope. (Possibly) build a new overload set containing only 357 // those declarations that are in scope. 358 OverloadedFunctionDecl *NewOvl = 0; 359 bool FoundInScope = false; 360 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 361 FEnd = Ovl->function_end(); 362 F != FEnd; ++F) { 363 NamedDecl *FD = F->get(); 364 if (!isDeclInScope(FD, Ctx, S)) { 365 if (!NewOvl && F != Ovl->function_begin()) { 366 NewOvl = OverloadedFunctionDecl::Create(Context, 367 F->get()->getDeclContext(), 368 F->get()->getDeclName()); 369 D = NewOvl; 370 for (OverloadedFunctionDecl::function_iterator 371 First = Ovl->function_begin(); 372 First != F; ++First) 373 NewOvl->addOverload(*First); 374 } 375 } else { 376 FoundInScope = true; 377 if (NewOvl) 378 NewOvl->addOverload(*F); 379 } 380 } 381 382 return FoundInScope; 383 } 384 385 return IdResolver.isDeclInScope(D, Ctx, Context, S); 386} 387 388static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 389 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 390 return false; 391 392 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 393 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 394 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 395 if (!RD->hasTrivialConstructor()) 396 return false; 397 if (!RD->hasTrivialDestructor()) 398 return false; 399 } 400 } 401 } 402 403 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 404 !isa<ImplicitParamDecl>(D) && 405 D->getDeclContext()->isFunctionOrMethod()); 406} 407 408void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 409 if (S->decl_empty()) return; 410 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 411 "Scope shouldn't contain decls!"); 412 413 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 414 I != E; ++I) { 415 Decl *TmpD = (*I).getAs<Decl>(); 416 assert(TmpD && "This decl didn't get pushed??"); 417 418 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 419 NamedDecl *D = cast<NamedDecl>(TmpD); 420 421 if (!D->getDeclName()) continue; 422 423 // Diagnose unused variables in this scope. 424 if (ShouldDiagnoseUnusedDecl(D)) 425 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 426 427 // Remove this name from our lexical scope. 428 IdResolver.RemoveDecl(D); 429 } 430} 431 432/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 433/// return 0 if one not found. 434ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 435 // The third "scope" argument is 0 since we aren't enabling lazy built-in 436 // creation from this context. 437 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 438 439 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 440} 441 442/// getNonFieldDeclScope - Retrieves the innermost scope, starting 443/// from S, where a non-field would be declared. This routine copes 444/// with the difference between C and C++ scoping rules in structs and 445/// unions. For example, the following code is well-formed in C but 446/// ill-formed in C++: 447/// @code 448/// struct S6 { 449/// enum { BAR } e; 450/// }; 451/// 452/// void test_S6() { 453/// struct S6 a; 454/// a.e = BAR; 455/// } 456/// @endcode 457/// For the declaration of BAR, this routine will return a different 458/// scope. The scope S will be the scope of the unnamed enumeration 459/// within S6. In C++, this routine will return the scope associated 460/// with S6, because the enumeration's scope is a transparent 461/// context but structures can contain non-field names. In C, this 462/// routine will return the translation unit scope, since the 463/// enumeration's scope is a transparent context and structures cannot 464/// contain non-field names. 465Scope *Sema::getNonFieldDeclScope(Scope *S) { 466 while (((S->getFlags() & Scope::DeclScope) == 0) || 467 (S->getEntity() && 468 ((DeclContext *)S->getEntity())->isTransparentContext()) || 469 (S->isClassScope() && !getLangOptions().CPlusPlus)) 470 S = S->getParent(); 471 return S; 472} 473 474void Sema::InitBuiltinVaListType() { 475 if (!Context.getBuiltinVaListType().isNull()) 476 return; 477 478 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 479 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 480 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 481 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 482} 483 484/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 485/// file scope. lazily create a decl for it. ForRedeclaration is true 486/// if we're creating this built-in in anticipation of redeclaring the 487/// built-in. 488NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 489 Scope *S, bool ForRedeclaration, 490 SourceLocation Loc) { 491 Builtin::ID BID = (Builtin::ID)bid; 492 493 if (Context.BuiltinInfo.hasVAListUse(BID)) 494 InitBuiltinVaListType(); 495 496 ASTContext::GetBuiltinTypeError Error; 497 QualType R = Context.GetBuiltinType(BID, Error); 498 switch (Error) { 499 case ASTContext::GE_None: 500 // Okay 501 break; 502 503 case ASTContext::GE_Missing_stdio: 504 if (ForRedeclaration) 505 Diag(Loc, diag::err_implicit_decl_requires_stdio) 506 << Context.BuiltinInfo.GetName(BID); 507 return 0; 508 509 case ASTContext::GE_Missing_setjmp: 510 if (ForRedeclaration) 511 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 512 << Context.BuiltinInfo.GetName(BID); 513 return 0; 514 } 515 516 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 517 Diag(Loc, diag::ext_implicit_lib_function_decl) 518 << Context.BuiltinInfo.GetName(BID) 519 << R; 520 if (Context.BuiltinInfo.getHeaderName(BID) && 521 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 522 != Diagnostic::Ignored) 523 Diag(Loc, diag::note_please_include_header) 524 << Context.BuiltinInfo.getHeaderName(BID) 525 << Context.BuiltinInfo.GetName(BID); 526 } 527 528 FunctionDecl *New = FunctionDecl::Create(Context, 529 Context.getTranslationUnitDecl(), 530 Loc, II, R, /*DInfo=*/0, 531 FunctionDecl::Extern, false, 532 /*hasPrototype=*/true); 533 New->setImplicit(); 534 535 // Create Decl objects for each parameter, adding them to the 536 // FunctionDecl. 537 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 538 llvm::SmallVector<ParmVarDecl*, 16> Params; 539 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 540 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 541 FT->getArgType(i), /*DInfo=*/0, 542 VarDecl::None, 0)); 543 New->setParams(Context, Params.data(), Params.size()); 544 } 545 546 AddKnownFunctionAttributes(New); 547 548 // TUScope is the translation-unit scope to insert this function into. 549 // FIXME: This is hideous. We need to teach PushOnScopeChains to 550 // relate Scopes to DeclContexts, and probably eliminate CurContext 551 // entirely, but we're not there yet. 552 DeclContext *SavedContext = CurContext; 553 CurContext = Context.getTranslationUnitDecl(); 554 PushOnScopeChains(New, TUScope); 555 CurContext = SavedContext; 556 return New; 557} 558 559/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 560/// same name and scope as a previous declaration 'Old'. Figure out 561/// how to resolve this situation, merging decls or emitting 562/// diagnostics as appropriate. If there was an error, set New to be invalid. 563/// 564void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 565 // If either decl is known invalid already, set the new one to be invalid and 566 // don't bother doing any merging checks. 567 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 568 return New->setInvalidDecl(); 569 570 // Allow multiple definitions for ObjC built-in typedefs. 571 // FIXME: Verify the underlying types are equivalent! 572 if (getLangOptions().ObjC1) { 573 const IdentifierInfo *TypeID = New->getIdentifier(); 574 switch (TypeID->getLength()) { 575 default: break; 576 case 2: 577 if (!TypeID->isStr("id")) 578 break; 579 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 580 // Install the built-in type for 'id', ignoring the current definition. 581 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 582 return; 583 case 5: 584 if (!TypeID->isStr("Class")) 585 break; 586 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 587 // Install the built-in type for 'Class', ignoring the current definition. 588 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 589 return; 590 case 3: 591 if (!TypeID->isStr("SEL")) 592 break; 593 Context.setObjCSelType(Context.getTypeDeclType(New)); 594 return; 595 case 8: 596 if (!TypeID->isStr("Protocol")) 597 break; 598 Context.setObjCProtoType(New->getUnderlyingType()); 599 return; 600 } 601 // Fall through - the typedef name was not a builtin type. 602 } 603 // Verify the old decl was also a type. 604 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 605 if (!Old) { 606 Diag(New->getLocation(), diag::err_redefinition_different_kind) 607 << New->getDeclName(); 608 if (OldD->getLocation().isValid()) 609 Diag(OldD->getLocation(), diag::note_previous_definition); 610 return New->setInvalidDecl(); 611 } 612 613 // Determine the "old" type we'll use for checking and diagnostics. 614 QualType OldType; 615 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 616 OldType = OldTypedef->getUnderlyingType(); 617 else 618 OldType = Context.getTypeDeclType(Old); 619 620 // If the typedef types are not identical, reject them in all languages and 621 // with any extensions enabled. 622 623 if (OldType != New->getUnderlyingType() && 624 Context.getCanonicalType(OldType) != 625 Context.getCanonicalType(New->getUnderlyingType())) { 626 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 627 << New->getUnderlyingType() << OldType; 628 if (Old->getLocation().isValid()) 629 Diag(Old->getLocation(), diag::note_previous_definition); 630 return New->setInvalidDecl(); 631 } 632 633 if (getLangOptions().Microsoft) 634 return; 635 636 // C++ [dcl.typedef]p2: 637 // In a given non-class scope, a typedef specifier can be used to 638 // redefine the name of any type declared in that scope to refer 639 // to the type to which it already refers. 640 if (getLangOptions().CPlusPlus) { 641 if (!isa<CXXRecordDecl>(CurContext)) 642 return; 643 Diag(New->getLocation(), diag::err_redefinition) 644 << New->getDeclName(); 645 Diag(Old->getLocation(), diag::note_previous_definition); 646 return New->setInvalidDecl(); 647 } 648 649 // If we have a redefinition of a typedef in C, emit a warning. This warning 650 // is normally mapped to an error, but can be controlled with 651 // -Wtypedef-redefinition. If either the original or the redefinition is 652 // in a system header, don't emit this for compatibility with GCC. 653 if (PP.getDiagnostics().getSuppressSystemWarnings() && 654 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 655 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 656 return; 657 658 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 659 << New->getDeclName(); 660 Diag(Old->getLocation(), diag::note_previous_definition); 661 return; 662} 663 664/// DeclhasAttr - returns true if decl Declaration already has the target 665/// attribute. 666static bool 667DeclHasAttr(const Decl *decl, const Attr *target) { 668 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 669 if (attr->getKind() == target->getKind()) 670 return true; 671 672 return false; 673} 674 675/// MergeAttributes - append attributes from the Old decl to the New one. 676static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 677 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 678 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 679 Attr *NewAttr = attr->clone(C); 680 NewAttr->setInherited(true); 681 New->addAttr(NewAttr); 682 } 683 } 684} 685 686/// Used in MergeFunctionDecl to keep track of function parameters in 687/// C. 688struct GNUCompatibleParamWarning { 689 ParmVarDecl *OldParm; 690 ParmVarDecl *NewParm; 691 QualType PromotedType; 692}; 693 694/// MergeFunctionDecl - We just parsed a function 'New' from 695/// declarator D which has the same name and scope as a previous 696/// declaration 'Old'. Figure out how to resolve this situation, 697/// merging decls or emitting diagnostics as appropriate. 698/// 699/// In C++, New and Old must be declarations that are not 700/// overloaded. Use IsOverload to determine whether New and Old are 701/// overloaded, and to select the Old declaration that New should be 702/// merged with. 703/// 704/// Returns true if there was an error, false otherwise. 705bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 706 assert(!isa<OverloadedFunctionDecl>(OldD) && 707 "Cannot merge with an overloaded function declaration"); 708 709 // Verify the old decl was also a function. 710 FunctionDecl *Old = 0; 711 if (FunctionTemplateDecl *OldFunctionTemplate 712 = dyn_cast<FunctionTemplateDecl>(OldD)) 713 Old = OldFunctionTemplate->getTemplatedDecl(); 714 else 715 Old = dyn_cast<FunctionDecl>(OldD); 716 if (!Old) { 717 Diag(New->getLocation(), diag::err_redefinition_different_kind) 718 << New->getDeclName(); 719 Diag(OldD->getLocation(), diag::note_previous_definition); 720 return true; 721 } 722 723 // Determine whether the previous declaration was a definition, 724 // implicit declaration, or a declaration. 725 diag::kind PrevDiag; 726 if (Old->isThisDeclarationADefinition()) 727 PrevDiag = diag::note_previous_definition; 728 else if (Old->isImplicit()) 729 PrevDiag = diag::note_previous_implicit_declaration; 730 else 731 PrevDiag = diag::note_previous_declaration; 732 733 QualType OldQType = Context.getCanonicalType(Old->getType()); 734 QualType NewQType = Context.getCanonicalType(New->getType()); 735 736 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 737 New->getStorageClass() == FunctionDecl::Static && 738 Old->getStorageClass() != FunctionDecl::Static) { 739 Diag(New->getLocation(), diag::err_static_non_static) 740 << New; 741 Diag(Old->getLocation(), PrevDiag); 742 return true; 743 } 744 745 if (getLangOptions().CPlusPlus) { 746 // (C++98 13.1p2): 747 // Certain function declarations cannot be overloaded: 748 // -- Function declarations that differ only in the return type 749 // cannot be overloaded. 750 QualType OldReturnType 751 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 752 QualType NewReturnType 753 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 754 if (OldReturnType != NewReturnType) { 755 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 756 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 757 return true; 758 } 759 760 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 761 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 762 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 763 NewMethod->getLexicalDeclContext()->isRecord()) { 764 // -- Member function declarations with the same name and the 765 // same parameter types cannot be overloaded if any of them 766 // is a static member function declaration. 767 if (OldMethod->isStatic() || NewMethod->isStatic()) { 768 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 769 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 770 return true; 771 } 772 773 // C++ [class.mem]p1: 774 // [...] A member shall not be declared twice in the 775 // member-specification, except that a nested class or member 776 // class template can be declared and then later defined. 777 unsigned NewDiag; 778 if (isa<CXXConstructorDecl>(OldMethod)) 779 NewDiag = diag::err_constructor_redeclared; 780 else if (isa<CXXDestructorDecl>(NewMethod)) 781 NewDiag = diag::err_destructor_redeclared; 782 else if (isa<CXXConversionDecl>(NewMethod)) 783 NewDiag = diag::err_conv_function_redeclared; 784 else 785 NewDiag = diag::err_member_redeclared; 786 787 Diag(New->getLocation(), NewDiag); 788 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 789 } 790 791 // (C++98 8.3.5p3): 792 // All declarations for a function shall agree exactly in both the 793 // return type and the parameter-type-list. 794 if (OldQType == NewQType) 795 return MergeCompatibleFunctionDecls(New, Old); 796 797 // Fall through for conflicting redeclarations and redefinitions. 798 } 799 800 // C: Function types need to be compatible, not identical. This handles 801 // duplicate function decls like "void f(int); void f(enum X);" properly. 802 if (!getLangOptions().CPlusPlus && 803 Context.typesAreCompatible(OldQType, NewQType)) { 804 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 805 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 806 const FunctionProtoType *OldProto = 0; 807 if (isa<FunctionNoProtoType>(NewFuncType) && 808 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 809 // The old declaration provided a function prototype, but the 810 // new declaration does not. Merge in the prototype. 811 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 812 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 813 OldProto->arg_type_end()); 814 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 815 ParamTypes.data(), ParamTypes.size(), 816 OldProto->isVariadic(), 817 OldProto->getTypeQuals()); 818 New->setType(NewQType); 819 New->setHasInheritedPrototype(); 820 821 // Synthesize a parameter for each argument type. 822 llvm::SmallVector<ParmVarDecl*, 16> Params; 823 for (FunctionProtoType::arg_type_iterator 824 ParamType = OldProto->arg_type_begin(), 825 ParamEnd = OldProto->arg_type_end(); 826 ParamType != ParamEnd; ++ParamType) { 827 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 828 SourceLocation(), 0, 829 *ParamType, /*DInfo=*/0, 830 VarDecl::None, 0); 831 Param->setImplicit(); 832 Params.push_back(Param); 833 } 834 835 New->setParams(Context, Params.data(), Params.size()); 836 } 837 838 return MergeCompatibleFunctionDecls(New, Old); 839 } 840 841 // GNU C permits a K&R definition to follow a prototype declaration 842 // if the declared types of the parameters in the K&R definition 843 // match the types in the prototype declaration, even when the 844 // promoted types of the parameters from the K&R definition differ 845 // from the types in the prototype. GCC then keeps the types from 846 // the prototype. 847 // 848 // If a variadic prototype is followed by a non-variadic K&R definition, 849 // the K&R definition becomes variadic. This is sort of an edge case, but 850 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 851 // C99 6.9.1p8. 852 if (!getLangOptions().CPlusPlus && 853 Old->hasPrototype() && !New->hasPrototype() && 854 New->getType()->getAs<FunctionProtoType>() && 855 Old->getNumParams() == New->getNumParams()) { 856 llvm::SmallVector<QualType, 16> ArgTypes; 857 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 858 const FunctionProtoType *OldProto 859 = Old->getType()->getAs<FunctionProtoType>(); 860 const FunctionProtoType *NewProto 861 = New->getType()->getAs<FunctionProtoType>(); 862 863 // Determine whether this is the GNU C extension. 864 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 865 NewProto->getResultType()); 866 bool LooseCompatible = !MergedReturn.isNull(); 867 for (unsigned Idx = 0, End = Old->getNumParams(); 868 LooseCompatible && Idx != End; ++Idx) { 869 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 870 ParmVarDecl *NewParm = New->getParamDecl(Idx); 871 if (Context.typesAreCompatible(OldParm->getType(), 872 NewProto->getArgType(Idx))) { 873 ArgTypes.push_back(NewParm->getType()); 874 } else if (Context.typesAreCompatible(OldParm->getType(), 875 NewParm->getType())) { 876 GNUCompatibleParamWarning Warn 877 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 878 Warnings.push_back(Warn); 879 ArgTypes.push_back(NewParm->getType()); 880 } else 881 LooseCompatible = false; 882 } 883 884 if (LooseCompatible) { 885 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 886 Diag(Warnings[Warn].NewParm->getLocation(), 887 diag::ext_param_promoted_not_compatible_with_prototype) 888 << Warnings[Warn].PromotedType 889 << Warnings[Warn].OldParm->getType(); 890 Diag(Warnings[Warn].OldParm->getLocation(), 891 diag::note_previous_declaration); 892 } 893 894 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 895 ArgTypes.size(), 896 OldProto->isVariadic(), 0)); 897 return MergeCompatibleFunctionDecls(New, Old); 898 } 899 900 // Fall through to diagnose conflicting types. 901 } 902 903 // A function that has already been declared has been redeclared or defined 904 // with a different type- show appropriate diagnostic 905 if (unsigned BuiltinID = Old->getBuiltinID()) { 906 // The user has declared a builtin function with an incompatible 907 // signature. 908 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 909 // The function the user is redeclaring is a library-defined 910 // function like 'malloc' or 'printf'. Warn about the 911 // redeclaration, then pretend that we don't know about this 912 // library built-in. 913 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 914 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 915 << Old << Old->getType(); 916 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 917 Old->setInvalidDecl(); 918 return false; 919 } 920 921 PrevDiag = diag::note_previous_builtin_declaration; 922 } 923 924 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 925 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 926 return true; 927} 928 929/// \brief Completes the merge of two function declarations that are 930/// known to be compatible. 931/// 932/// This routine handles the merging of attributes and other 933/// properties of function declarations form the old declaration to 934/// the new declaration, once we know that New is in fact a 935/// redeclaration of Old. 936/// 937/// \returns false 938bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 939 // Merge the attributes 940 MergeAttributes(New, Old, Context); 941 942 // Merge the storage class. 943 if (Old->getStorageClass() != FunctionDecl::Extern && 944 Old->getStorageClass() != FunctionDecl::None) 945 New->setStorageClass(Old->getStorageClass()); 946 947 // Merge "pure" flag. 948 if (Old->isPure()) 949 New->setPure(); 950 951 // Merge the "deleted" flag. 952 if (Old->isDeleted()) 953 New->setDeleted(); 954 955 if (getLangOptions().CPlusPlus) 956 return MergeCXXFunctionDecl(New, Old); 957 958 return false; 959} 960 961/// MergeVarDecl - We just parsed a variable 'New' which has the same name 962/// and scope as a previous declaration 'Old'. Figure out how to resolve this 963/// situation, merging decls or emitting diagnostics as appropriate. 964/// 965/// Tentative definition rules (C99 6.9.2p2) are checked by 966/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 967/// definitions here, since the initializer hasn't been attached. 968/// 969void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 970 // If either decl is invalid, make sure the new one is marked invalid and 971 // don't do any other checking. 972 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 973 return New->setInvalidDecl(); 974 975 // Verify the old decl was also a variable. 976 VarDecl *Old = dyn_cast<VarDecl>(OldD); 977 if (!Old) { 978 Diag(New->getLocation(), diag::err_redefinition_different_kind) 979 << New->getDeclName(); 980 Diag(OldD->getLocation(), diag::note_previous_definition); 981 return New->setInvalidDecl(); 982 } 983 984 MergeAttributes(New, Old, Context); 985 986 // Merge the types 987 QualType MergedT; 988 if (getLangOptions().CPlusPlus) { 989 if (Context.hasSameType(New->getType(), Old->getType())) 990 MergedT = New->getType(); 991 // C++ [basic.types]p7: 992 // [...] The declared type of an array object might be an array of 993 // unknown size and therefore be incomplete at one point in a 994 // translation unit and complete later on; [...] 995 else if (Old->getType()->isIncompleteArrayType() && 996 New->getType()->isArrayType()) { 997 CanQual<ArrayType> OldArray 998 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 999 CanQual<ArrayType> NewArray 1000 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1001 if (OldArray->getElementType() == NewArray->getElementType()) 1002 MergedT = New->getType(); 1003 } 1004 } else { 1005 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1006 } 1007 if (MergedT.isNull()) { 1008 Diag(New->getLocation(), diag::err_redefinition_different_type) 1009 << New->getDeclName(); 1010 Diag(Old->getLocation(), diag::note_previous_definition); 1011 return New->setInvalidDecl(); 1012 } 1013 New->setType(MergedT); 1014 1015 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1016 if (New->getStorageClass() == VarDecl::Static && 1017 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1018 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1019 Diag(Old->getLocation(), diag::note_previous_definition); 1020 return New->setInvalidDecl(); 1021 } 1022 // C99 6.2.2p4: 1023 // For an identifier declared with the storage-class specifier 1024 // extern in a scope in which a prior declaration of that 1025 // identifier is visible,23) if the prior declaration specifies 1026 // internal or external linkage, the linkage of the identifier at 1027 // the later declaration is the same as the linkage specified at 1028 // the prior declaration. If no prior declaration is visible, or 1029 // if the prior declaration specifies no linkage, then the 1030 // identifier has external linkage. 1031 if (New->hasExternalStorage() && Old->hasLinkage()) 1032 /* Okay */; 1033 else if (New->getStorageClass() != VarDecl::Static && 1034 Old->getStorageClass() == VarDecl::Static) { 1035 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1036 Diag(Old->getLocation(), diag::note_previous_definition); 1037 return New->setInvalidDecl(); 1038 } 1039 1040 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1041 1042 // FIXME: The test for external storage here seems wrong? We still 1043 // need to check for mismatches. 1044 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1045 // Don't complain about out-of-line definitions of static members. 1046 !(Old->getLexicalDeclContext()->isRecord() && 1047 !New->getLexicalDeclContext()->isRecord())) { 1048 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1049 Diag(Old->getLocation(), diag::note_previous_definition); 1050 return New->setInvalidDecl(); 1051 } 1052 1053 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1054 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1055 Diag(Old->getLocation(), diag::note_previous_definition); 1056 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1057 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1058 Diag(Old->getLocation(), diag::note_previous_definition); 1059 } 1060 1061 // Keep a chain of previous declarations. 1062 New->setPreviousDeclaration(Old); 1063} 1064 1065/// CheckFallThrough - Check that we don't fall off the end of a 1066/// Statement that should return a value. 1067/// 1068/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1069/// MaybeFallThrough iff we might or might not fall off the end, 1070/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1071/// return. We assume NeverFallThrough iff we never fall off the end of the 1072/// statement but we may return. We assume that functions not marked noreturn 1073/// will return. 1074Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1075 // FIXME: Eventually share this CFG object when we have other warnings based 1076 // of the CFG. This can be done using AnalysisContext. 1077 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1078 1079 // FIXME: They should never return 0, fix that, delete this code. 1080 if (cfg == 0) 1081 // FIXME: This should be NeverFallThrough 1082 return NeverFallThroughOrReturn; 1083 // The CFG leaves in dead things, and we don't want to dead code paths to 1084 // confuse us, so we mark all live things first. 1085 std::queue<CFGBlock*> workq; 1086 llvm::BitVector live(cfg->getNumBlockIDs()); 1087 // Prep work queue 1088 workq.push(&cfg->getEntry()); 1089 // Solve 1090 while (!workq.empty()) { 1091 CFGBlock *item = workq.front(); 1092 workq.pop(); 1093 live.set(item->getBlockID()); 1094 for (CFGBlock::succ_iterator I=item->succ_begin(), 1095 E=item->succ_end(); 1096 I != E; 1097 ++I) { 1098 if ((*I) && !live[(*I)->getBlockID()]) { 1099 live.set((*I)->getBlockID()); 1100 workq.push(*I); 1101 } 1102 } 1103 } 1104 1105 // Now we know what is live, we check the live precessors of the exit block 1106 // and look for fall through paths, being careful to ignore normal returns, 1107 // and exceptional paths. 1108 bool HasLiveReturn = false; 1109 bool HasFakeEdge = false; 1110 bool HasPlainEdge = false; 1111 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1112 E = cfg->getExit().pred_end(); 1113 I != E; 1114 ++I) { 1115 CFGBlock& B = **I; 1116 if (!live[B.getBlockID()]) 1117 continue; 1118 if (B.size() == 0) { 1119 // A labeled empty statement, or the entry block... 1120 HasPlainEdge = true; 1121 continue; 1122 } 1123 Stmt *S = B[B.size()-1]; 1124 if (isa<ReturnStmt>(S)) { 1125 HasLiveReturn = true; 1126 continue; 1127 } 1128 if (isa<ObjCAtThrowStmt>(S)) { 1129 HasFakeEdge = true; 1130 continue; 1131 } 1132 if (isa<CXXThrowExpr>(S)) { 1133 HasFakeEdge = true; 1134 continue; 1135 } 1136 bool NoReturnEdge = false; 1137 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1138 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1139 if (CEE->getType().getNoReturnAttr()) { 1140 NoReturnEdge = true; 1141 HasFakeEdge = true; 1142 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1143 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1144 if (FD->hasAttr<NoReturnAttr>()) { 1145 NoReturnEdge = true; 1146 HasFakeEdge = true; 1147 } 1148 } 1149 } 1150 } 1151 // FIXME: Add noreturn message sends. 1152 if (NoReturnEdge == false) 1153 HasPlainEdge = true; 1154 } 1155 if (!HasPlainEdge) { 1156 if (HasLiveReturn) 1157 return NeverFallThrough; 1158 return NeverFallThroughOrReturn; 1159 } 1160 if (HasFakeEdge || HasLiveReturn) 1161 return MaybeFallThrough; 1162 // This says AlwaysFallThrough for calls to functions that are not marked 1163 // noreturn, that don't return. If people would like this warning to be more 1164 // accurate, such functions should be marked as noreturn. 1165 return AlwaysFallThrough; 1166} 1167 1168/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1169/// function that should return a value. Check that we don't fall off the end 1170/// of a noreturn function. We assume that functions and blocks not marked 1171/// noreturn will return. 1172void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1173 // FIXME: Would be nice if we had a better way to control cascading errors, 1174 // but for now, avoid them. The problem is that when Parse sees: 1175 // int foo() { return a; } 1176 // The return is eaten and the Sema code sees just: 1177 // int foo() { } 1178 // which this code would then warn about. 1179 if (getDiagnostics().hasErrorOccurred()) 1180 return; 1181 1182 bool ReturnsVoid = false; 1183 bool HasNoReturn = false; 1184 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1185 // If the result type of the function is a dependent type, we don't know 1186 // whether it will be void or not, so don't 1187 if (FD->getResultType()->isDependentType()) 1188 return; 1189 if (FD->getResultType()->isVoidType()) 1190 ReturnsVoid = true; 1191 if (FD->hasAttr<NoReturnAttr>()) 1192 HasNoReturn = true; 1193 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1194 if (MD->getResultType()->isVoidType()) 1195 ReturnsVoid = true; 1196 if (MD->hasAttr<NoReturnAttr>()) 1197 HasNoReturn = true; 1198 } 1199 1200 // Short circuit for compilation speed. 1201 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1202 == Diagnostic::Ignored || ReturnsVoid) 1203 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1204 == Diagnostic::Ignored || !HasNoReturn) 1205 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1206 == Diagnostic::Ignored || !ReturnsVoid)) 1207 return; 1208 // FIXME: Function try block 1209 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1210 switch (CheckFallThrough(Body)) { 1211 case MaybeFallThrough: 1212 if (HasNoReturn) 1213 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1214 else if (!ReturnsVoid) 1215 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1216 break; 1217 case AlwaysFallThrough: 1218 if (HasNoReturn) 1219 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1220 else if (!ReturnsVoid) 1221 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1222 break; 1223 case NeverFallThroughOrReturn: 1224 if (ReturnsVoid && !HasNoReturn) 1225 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1226 break; 1227 case NeverFallThrough: 1228 break; 1229 } 1230 } 1231} 1232 1233/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1234/// that should return a value. Check that we don't fall off the end of a 1235/// noreturn block. We assume that functions and blocks not marked noreturn 1236/// will return. 1237void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1238 // FIXME: Would be nice if we had a better way to control cascading errors, 1239 // but for now, avoid them. The problem is that when Parse sees: 1240 // int foo() { return a; } 1241 // The return is eaten and the Sema code sees just: 1242 // int foo() { } 1243 // which this code would then warn about. 1244 if (getDiagnostics().hasErrorOccurred()) 1245 return; 1246 bool ReturnsVoid = false; 1247 bool HasNoReturn = false; 1248 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1249 if (FT->getResultType()->isVoidType()) 1250 ReturnsVoid = true; 1251 if (FT->getNoReturnAttr()) 1252 HasNoReturn = true; 1253 } 1254 1255 // Short circuit for compilation speed. 1256 if (ReturnsVoid 1257 && !HasNoReturn 1258 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1259 == Diagnostic::Ignored || !ReturnsVoid)) 1260 return; 1261 // FIXME: Funtion try block 1262 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1263 switch (CheckFallThrough(Body)) { 1264 case MaybeFallThrough: 1265 if (HasNoReturn) 1266 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1267 else if (!ReturnsVoid) 1268 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1269 break; 1270 case AlwaysFallThrough: 1271 if (HasNoReturn) 1272 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1273 else if (!ReturnsVoid) 1274 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1275 break; 1276 case NeverFallThroughOrReturn: 1277 if (ReturnsVoid) 1278 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1279 break; 1280 case NeverFallThrough: 1281 break; 1282 } 1283 } 1284} 1285 1286/// CheckParmsForFunctionDef - Check that the parameters of the given 1287/// function are appropriate for the definition of a function. This 1288/// takes care of any checks that cannot be performed on the 1289/// declaration itself, e.g., that the types of each of the function 1290/// parameters are complete. 1291bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1292 bool HasInvalidParm = false; 1293 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1294 ParmVarDecl *Param = FD->getParamDecl(p); 1295 1296 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1297 // function declarator that is part of a function definition of 1298 // that function shall not have incomplete type. 1299 // 1300 // This is also C++ [dcl.fct]p6. 1301 if (!Param->isInvalidDecl() && 1302 RequireCompleteType(Param->getLocation(), Param->getType(), 1303 diag::err_typecheck_decl_incomplete_type)) { 1304 Param->setInvalidDecl(); 1305 HasInvalidParm = true; 1306 } 1307 1308 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1309 // declaration of each parameter shall include an identifier. 1310 if (Param->getIdentifier() == 0 && 1311 !Param->isImplicit() && 1312 !getLangOptions().CPlusPlus) 1313 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1314 } 1315 1316 return HasInvalidParm; 1317} 1318 1319/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1320/// no declarator (e.g. "struct foo;") is parsed. 1321Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1322 // FIXME: Error on auto/register at file scope 1323 // FIXME: Error on inline/virtual/explicit 1324 // FIXME: Error on invalid restrict 1325 // FIXME: Warn on useless __thread 1326 // FIXME: Warn on useless const/volatile 1327 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1328 // FIXME: Warn on useless attributes 1329 Decl *TagD = 0; 1330 TagDecl *Tag = 0; 1331 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1332 DS.getTypeSpecType() == DeclSpec::TST_struct || 1333 DS.getTypeSpecType() == DeclSpec::TST_union || 1334 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1335 TagD = static_cast<Decl *>(DS.getTypeRep()); 1336 1337 if (!TagD) // We probably had an error 1338 return DeclPtrTy(); 1339 1340 // Note that the above type specs guarantee that the 1341 // type rep is a Decl, whereas in many of the others 1342 // it's a Type. 1343 Tag = dyn_cast<TagDecl>(TagD); 1344 } 1345 1346 if (DS.isFriendSpecified()) { 1347 // If we're dealing with a class template decl, assume that the 1348 // template routines are handling it. 1349 if (TagD && isa<ClassTemplateDecl>(TagD)) 1350 return DeclPtrTy(); 1351 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1352 } 1353 1354 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1355 // If there are attributes in the DeclSpec, apply them to the record. 1356 if (const AttributeList *AL = DS.getAttributes()) 1357 ProcessDeclAttributeList(S, Record, AL); 1358 1359 if (!Record->getDeclName() && Record->isDefinition() && 1360 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1361 if (getLangOptions().CPlusPlus || 1362 Record->getDeclContext()->isRecord()) 1363 return BuildAnonymousStructOrUnion(S, DS, Record); 1364 1365 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1366 << DS.getSourceRange(); 1367 } 1368 1369 // Microsoft allows unnamed struct/union fields. Don't complain 1370 // about them. 1371 // FIXME: Should we support Microsoft's extensions in this area? 1372 if (Record->getDeclName() && getLangOptions().Microsoft) 1373 return DeclPtrTy::make(Tag); 1374 } 1375 1376 if (!DS.isMissingDeclaratorOk() && 1377 DS.getTypeSpecType() != DeclSpec::TST_error) { 1378 // Warn about typedefs of enums without names, since this is an 1379 // extension in both Microsoft an GNU. 1380 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1381 Tag && isa<EnumDecl>(Tag)) { 1382 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1383 << DS.getSourceRange(); 1384 return DeclPtrTy::make(Tag); 1385 } 1386 1387 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1388 << DS.getSourceRange(); 1389 return DeclPtrTy(); 1390 } 1391 1392 return DeclPtrTy::make(Tag); 1393} 1394 1395/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1396/// anonymous struct or union AnonRecord into the owning context Owner 1397/// and scope S. This routine will be invoked just after we realize 1398/// that an unnamed union or struct is actually an anonymous union or 1399/// struct, e.g., 1400/// 1401/// @code 1402/// union { 1403/// int i; 1404/// float f; 1405/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1406/// // f into the surrounding scope.x 1407/// @endcode 1408/// 1409/// This routine is recursive, injecting the names of nested anonymous 1410/// structs/unions into the owning context and scope as well. 1411bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1412 RecordDecl *AnonRecord) { 1413 bool Invalid = false; 1414 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1415 FEnd = AnonRecord->field_end(); 1416 F != FEnd; ++F) { 1417 if ((*F)->getDeclName()) { 1418 LookupResult R; 1419 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1420 LookupOrdinaryName, true); 1421 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1422 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1423 // C++ [class.union]p2: 1424 // The names of the members of an anonymous union shall be 1425 // distinct from the names of any other entity in the 1426 // scope in which the anonymous union is declared. 1427 unsigned diagKind 1428 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1429 : diag::err_anonymous_struct_member_redecl; 1430 Diag((*F)->getLocation(), diagKind) 1431 << (*F)->getDeclName(); 1432 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1433 Invalid = true; 1434 } else { 1435 // C++ [class.union]p2: 1436 // For the purpose of name lookup, after the anonymous union 1437 // definition, the members of the anonymous union are 1438 // considered to have been defined in the scope in which the 1439 // anonymous union is declared. 1440 Owner->makeDeclVisibleInContext(*F); 1441 S->AddDecl(DeclPtrTy::make(*F)); 1442 IdResolver.AddDecl(*F); 1443 } 1444 } else if (const RecordType *InnerRecordType 1445 = (*F)->getType()->getAs<RecordType>()) { 1446 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1447 if (InnerRecord->isAnonymousStructOrUnion()) 1448 Invalid = Invalid || 1449 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1450 } 1451 } 1452 1453 return Invalid; 1454} 1455 1456/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1457/// anonymous structure or union. Anonymous unions are a C++ feature 1458/// (C++ [class.union]) and a GNU C extension; anonymous structures 1459/// are a GNU C and GNU C++ extension. 1460Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1461 RecordDecl *Record) { 1462 DeclContext *Owner = Record->getDeclContext(); 1463 1464 // Diagnose whether this anonymous struct/union is an extension. 1465 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1466 Diag(Record->getLocation(), diag::ext_anonymous_union); 1467 else if (!Record->isUnion()) 1468 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1469 1470 // C and C++ require different kinds of checks for anonymous 1471 // structs/unions. 1472 bool Invalid = false; 1473 if (getLangOptions().CPlusPlus) { 1474 const char* PrevSpec = 0; 1475 unsigned DiagID; 1476 // C++ [class.union]p3: 1477 // Anonymous unions declared in a named namespace or in the 1478 // global namespace shall be declared static. 1479 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1480 (isa<TranslationUnitDecl>(Owner) || 1481 (isa<NamespaceDecl>(Owner) && 1482 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1483 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1484 Invalid = true; 1485 1486 // Recover by adding 'static'. 1487 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1488 PrevSpec, DiagID); 1489 } 1490 // C++ [class.union]p3: 1491 // A storage class is not allowed in a declaration of an 1492 // anonymous union in a class scope. 1493 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1494 isa<RecordDecl>(Owner)) { 1495 Diag(DS.getStorageClassSpecLoc(), 1496 diag::err_anonymous_union_with_storage_spec); 1497 Invalid = true; 1498 1499 // Recover by removing the storage specifier. 1500 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1501 PrevSpec, DiagID); 1502 } 1503 1504 // C++ [class.union]p2: 1505 // The member-specification of an anonymous union shall only 1506 // define non-static data members. [Note: nested types and 1507 // functions cannot be declared within an anonymous union. ] 1508 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1509 MemEnd = Record->decls_end(); 1510 Mem != MemEnd; ++Mem) { 1511 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1512 // C++ [class.union]p3: 1513 // An anonymous union shall not have private or protected 1514 // members (clause 11). 1515 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1516 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1517 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1518 Invalid = true; 1519 } 1520 } else if ((*Mem)->isImplicit()) { 1521 // Any implicit members are fine. 1522 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1523 // This is a type that showed up in an 1524 // elaborated-type-specifier inside the anonymous struct or 1525 // union, but which actually declares a type outside of the 1526 // anonymous struct or union. It's okay. 1527 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1528 if (!MemRecord->isAnonymousStructOrUnion() && 1529 MemRecord->getDeclName()) { 1530 // This is a nested type declaration. 1531 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1532 << (int)Record->isUnion(); 1533 Invalid = true; 1534 } 1535 } else { 1536 // We have something that isn't a non-static data 1537 // member. Complain about it. 1538 unsigned DK = diag::err_anonymous_record_bad_member; 1539 if (isa<TypeDecl>(*Mem)) 1540 DK = diag::err_anonymous_record_with_type; 1541 else if (isa<FunctionDecl>(*Mem)) 1542 DK = diag::err_anonymous_record_with_function; 1543 else if (isa<VarDecl>(*Mem)) 1544 DK = diag::err_anonymous_record_with_static; 1545 Diag((*Mem)->getLocation(), DK) 1546 << (int)Record->isUnion(); 1547 Invalid = true; 1548 } 1549 } 1550 } 1551 1552 if (!Record->isUnion() && !Owner->isRecord()) { 1553 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1554 << (int)getLangOptions().CPlusPlus; 1555 Invalid = true; 1556 } 1557 1558 // Mock up a declarator. 1559 Declarator Dc(DS, Declarator::TypeNameContext); 1560 DeclaratorInfo *DInfo = 0; 1561 GetTypeForDeclarator(Dc, S, &DInfo); 1562 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1563 1564 // Create a declaration for this anonymous struct/union. 1565 NamedDecl *Anon = 0; 1566 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1567 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1568 /*IdentifierInfo=*/0, 1569 Context.getTypeDeclType(Record), 1570 DInfo, 1571 /*BitWidth=*/0, /*Mutable=*/false); 1572 Anon->setAccess(AS_public); 1573 if (getLangOptions().CPlusPlus) 1574 FieldCollector->Add(cast<FieldDecl>(Anon)); 1575 } else { 1576 VarDecl::StorageClass SC; 1577 switch (DS.getStorageClassSpec()) { 1578 default: assert(0 && "Unknown storage class!"); 1579 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1580 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1581 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1582 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1583 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1584 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1585 case DeclSpec::SCS_mutable: 1586 // mutable can only appear on non-static class members, so it's always 1587 // an error here 1588 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1589 Invalid = true; 1590 SC = VarDecl::None; 1591 break; 1592 } 1593 1594 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1595 /*IdentifierInfo=*/0, 1596 Context.getTypeDeclType(Record), 1597 DInfo, 1598 SC); 1599 } 1600 Anon->setImplicit(); 1601 1602 // Add the anonymous struct/union object to the current 1603 // context. We'll be referencing this object when we refer to one of 1604 // its members. 1605 Owner->addDecl(Anon); 1606 1607 // Inject the members of the anonymous struct/union into the owning 1608 // context and into the identifier resolver chain for name lookup 1609 // purposes. 1610 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1611 Invalid = true; 1612 1613 // Mark this as an anonymous struct/union type. Note that we do not 1614 // do this until after we have already checked and injected the 1615 // members of this anonymous struct/union type, because otherwise 1616 // the members could be injected twice: once by DeclContext when it 1617 // builds its lookup table, and once by 1618 // InjectAnonymousStructOrUnionMembers. 1619 Record->setAnonymousStructOrUnion(true); 1620 1621 if (Invalid) 1622 Anon->setInvalidDecl(); 1623 1624 return DeclPtrTy::make(Anon); 1625} 1626 1627 1628/// GetNameForDeclarator - Determine the full declaration name for the 1629/// given Declarator. 1630DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1631 return GetNameFromUnqualifiedId(D.getName()); 1632} 1633 1634/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1635DeclarationName Sema::GetNameFromUnqualifiedId(UnqualifiedId &Name) { 1636 switch (Name.getKind()) { 1637 case UnqualifiedId::IK_Identifier: 1638 return DeclarationName(Name.Identifier); 1639 1640 case UnqualifiedId::IK_OperatorFunctionId: 1641 return Context.DeclarationNames.getCXXOperatorName( 1642 Name.OperatorFunctionId.Operator); 1643 1644 case UnqualifiedId::IK_ConversionFunctionId: { 1645 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1646 if (Ty.isNull()) 1647 return DeclarationName(); 1648 1649 return Context.DeclarationNames.getCXXConversionFunctionName( 1650 Context.getCanonicalType(Ty)); 1651 } 1652 1653 case UnqualifiedId::IK_ConstructorName: { 1654 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1655 if (Ty.isNull()) 1656 return DeclarationName(); 1657 1658 return Context.DeclarationNames.getCXXConstructorName( 1659 Context.getCanonicalType(Ty)); 1660 } 1661 1662 case UnqualifiedId::IK_DestructorName: { 1663 QualType Ty = GetTypeFromParser(Name.DestructorName); 1664 if (Ty.isNull()) 1665 return DeclarationName(); 1666 1667 return Context.DeclarationNames.getCXXDestructorName( 1668 Context.getCanonicalType(Ty)); 1669 } 1670 1671 case UnqualifiedId::IK_TemplateId: { 1672 TemplateName TName 1673 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1674 if (TemplateDecl *Template = TName.getAsTemplateDecl()) 1675 return Template->getDeclName(); 1676 if (OverloadedFunctionDecl *Ovl = TName.getAsOverloadedFunctionDecl()) 1677 return Ovl->getDeclName(); 1678 1679 return DeclarationName(); 1680 } 1681 } 1682 1683 assert(false && "Unknown name kind"); 1684 return DeclarationName(); 1685} 1686 1687/// isNearlyMatchingFunction - Determine whether the C++ functions 1688/// Declaration and Definition are "nearly" matching. This heuristic 1689/// is used to improve diagnostics in the case where an out-of-line 1690/// function definition doesn't match any declaration within 1691/// the class or namespace. 1692static bool isNearlyMatchingFunction(ASTContext &Context, 1693 FunctionDecl *Declaration, 1694 FunctionDecl *Definition) { 1695 if (Declaration->param_size() != Definition->param_size()) 1696 return false; 1697 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1698 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1699 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1700 1701 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1702 DefParamTy.getNonReferenceType())) 1703 return false; 1704 } 1705 1706 return true; 1707} 1708 1709Sema::DeclPtrTy 1710Sema::HandleDeclarator(Scope *S, Declarator &D, 1711 MultiTemplateParamsArg TemplateParamLists, 1712 bool IsFunctionDefinition) { 1713 DeclarationName Name = GetNameForDeclarator(D); 1714 1715 // All of these full declarators require an identifier. If it doesn't have 1716 // one, the ParsedFreeStandingDeclSpec action should be used. 1717 if (!Name) { 1718 if (!D.isInvalidType()) // Reject this if we think it is valid. 1719 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1720 diag::err_declarator_need_ident) 1721 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1722 return DeclPtrTy(); 1723 } 1724 1725 // The scope passed in may not be a decl scope. Zip up the scope tree until 1726 // we find one that is. 1727 while ((S->getFlags() & Scope::DeclScope) == 0 || 1728 (S->getFlags() & Scope::TemplateParamScope) != 0) 1729 S = S->getParent(); 1730 1731 // If this is an out-of-line definition of a member of a class template 1732 // or class template partial specialization, we may need to rebuild the 1733 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1734 // for more information. 1735 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1736 // handle expressions properly. 1737 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1738 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1739 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1740 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1741 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1742 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1743 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1744 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1745 // FIXME: Preserve type source info. 1746 QualType T = GetTypeFromParser(DS.getTypeRep()); 1747 EnterDeclaratorContext(S, DC); 1748 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1749 ExitDeclaratorContext(S); 1750 if (T.isNull()) 1751 return DeclPtrTy(); 1752 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1753 } 1754 } 1755 1756 DeclContext *DC; 1757 NamedDecl *PrevDecl; 1758 NamedDecl *New; 1759 1760 DeclaratorInfo *DInfo = 0; 1761 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1762 1763 // See if this is a redefinition of a variable in the same scope. 1764 if (D.getCXXScopeSpec().isInvalid()) { 1765 DC = CurContext; 1766 PrevDecl = 0; 1767 D.setInvalidType(); 1768 } else if (!D.getCXXScopeSpec().isSet()) { 1769 LookupNameKind NameKind = LookupOrdinaryName; 1770 1771 // If the declaration we're planning to build will be a function 1772 // or object with linkage, then look for another declaration with 1773 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1774 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1775 /* Do nothing*/; 1776 else if (R->isFunctionType()) { 1777 if (CurContext->isFunctionOrMethod() || 1778 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1779 NameKind = LookupRedeclarationWithLinkage; 1780 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1781 NameKind = LookupRedeclarationWithLinkage; 1782 else if (CurContext->getLookupContext()->isTranslationUnit() && 1783 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1784 NameKind = LookupRedeclarationWithLinkage; 1785 1786 DC = CurContext; 1787 LookupResult R; 1788 LookupName(R, S, Name, NameKind, true, 1789 NameKind == LookupRedeclarationWithLinkage, 1790 D.getIdentifierLoc()); 1791 PrevDecl = R.getAsSingleDecl(Context); 1792 } else { // Something like "int foo::x;" 1793 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1794 1795 if (!DC) { 1796 // If we could not compute the declaration context, it's because the 1797 // declaration context is dependent but does not refer to a class, 1798 // class template, or class template partial specialization. Complain 1799 // and return early, to avoid the coming semantic disaster. 1800 Diag(D.getIdentifierLoc(), 1801 diag::err_template_qualified_declarator_no_match) 1802 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1803 << D.getCXXScopeSpec().getRange(); 1804 return DeclPtrTy(); 1805 } 1806 1807 if (!DC->isDependentContext() && 1808 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1809 return DeclPtrTy(); 1810 1811 LookupResult Res; 1812 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1813 PrevDecl = Res.getAsSingleDecl(Context); 1814 1815 // C++ 7.3.1.2p2: 1816 // Members (including explicit specializations of templates) of a named 1817 // namespace can also be defined outside that namespace by explicit 1818 // qualification of the name being defined, provided that the entity being 1819 // defined was already declared in the namespace and the definition appears 1820 // after the point of declaration in a namespace that encloses the 1821 // declarations namespace. 1822 // 1823 // Note that we only check the context at this point. We don't yet 1824 // have enough information to make sure that PrevDecl is actually 1825 // the declaration we want to match. For example, given: 1826 // 1827 // class X { 1828 // void f(); 1829 // void f(float); 1830 // }; 1831 // 1832 // void X::f(int) { } // ill-formed 1833 // 1834 // In this case, PrevDecl will point to the overload set 1835 // containing the two f's declared in X, but neither of them 1836 // matches. 1837 1838 // First check whether we named the global scope. 1839 if (isa<TranslationUnitDecl>(DC)) { 1840 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1841 << Name << D.getCXXScopeSpec().getRange(); 1842 } else { 1843 DeclContext *Cur = CurContext; 1844 while (isa<LinkageSpecDecl>(Cur)) 1845 Cur = Cur->getParent(); 1846 if (!Cur->Encloses(DC)) { 1847 // The qualifying scope doesn't enclose the original declaration. 1848 // Emit diagnostic based on current scope. 1849 SourceLocation L = D.getIdentifierLoc(); 1850 SourceRange R = D.getCXXScopeSpec().getRange(); 1851 if (isa<FunctionDecl>(Cur)) 1852 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1853 else 1854 Diag(L, diag::err_invalid_declarator_scope) 1855 << Name << cast<NamedDecl>(DC) << R; 1856 D.setInvalidType(); 1857 } 1858 } 1859 } 1860 1861 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1862 // Maybe we will complain about the shadowed template parameter. 1863 if (!D.isInvalidType()) 1864 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1865 D.setInvalidType(); 1866 1867 // Just pretend that we didn't see the previous declaration. 1868 PrevDecl = 0; 1869 } 1870 1871 // In C++, the previous declaration we find might be a tag type 1872 // (class or enum). In this case, the new declaration will hide the 1873 // tag type. Note that this does does not apply if we're declaring a 1874 // typedef (C++ [dcl.typedef]p4). 1875 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1876 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1877 PrevDecl = 0; 1878 1879 bool Redeclaration = false; 1880 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1881 if (TemplateParamLists.size()) { 1882 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1883 return DeclPtrTy(); 1884 } 1885 1886 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1887 } else if (R->isFunctionType()) { 1888 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1889 move(TemplateParamLists), 1890 IsFunctionDefinition, Redeclaration); 1891 } else { 1892 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1893 move(TemplateParamLists), 1894 Redeclaration); 1895 } 1896 1897 if (New == 0) 1898 return DeclPtrTy(); 1899 1900 // If this has an identifier and is not an invalid redeclaration or 1901 // function template specialization, add it to the scope stack. 1902 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1903 !(isa<FunctionDecl>(New) && 1904 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1905 PushOnScopeChains(New, S); 1906 1907 return DeclPtrTy::make(New); 1908} 1909 1910/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1911/// types into constant array types in certain situations which would otherwise 1912/// be errors (for GCC compatibility). 1913static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1914 ASTContext &Context, 1915 bool &SizeIsNegative) { 1916 // This method tries to turn a variable array into a constant 1917 // array even when the size isn't an ICE. This is necessary 1918 // for compatibility with code that depends on gcc's buggy 1919 // constant expression folding, like struct {char x[(int)(char*)2];} 1920 SizeIsNegative = false; 1921 1922 QualifierCollector Qs; 1923 const Type *Ty = Qs.strip(T); 1924 1925 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1926 QualType Pointee = PTy->getPointeeType(); 1927 QualType FixedType = 1928 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1929 if (FixedType.isNull()) return FixedType; 1930 FixedType = Context.getPointerType(FixedType); 1931 return Qs.apply(FixedType); 1932 } 1933 1934 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1935 if (!VLATy) 1936 return QualType(); 1937 // FIXME: We should probably handle this case 1938 if (VLATy->getElementType()->isVariablyModifiedType()) 1939 return QualType(); 1940 1941 Expr::EvalResult EvalResult; 1942 if (!VLATy->getSizeExpr() || 1943 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1944 !EvalResult.Val.isInt()) 1945 return QualType(); 1946 1947 llvm::APSInt &Res = EvalResult.Val.getInt(); 1948 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1949 // TODO: preserve the size expression in declarator info 1950 return Context.getConstantArrayType(VLATy->getElementType(), 1951 Res, ArrayType::Normal, 0); 1952 } 1953 1954 SizeIsNegative = true; 1955 return QualType(); 1956} 1957 1958/// \brief Register the given locally-scoped external C declaration so 1959/// that it can be found later for redeclarations 1960void 1961Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1962 Scope *S) { 1963 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1964 "Decl is not a locally-scoped decl!"); 1965 // Note that we have a locally-scoped external with this name. 1966 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1967 1968 if (!PrevDecl) 1969 return; 1970 1971 // If there was a previous declaration of this variable, it may be 1972 // in our identifier chain. Update the identifier chain with the new 1973 // declaration. 1974 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1975 // The previous declaration was found on the identifer resolver 1976 // chain, so remove it from its scope. 1977 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1978 S = S->getParent(); 1979 1980 if (S) 1981 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1982 } 1983} 1984 1985/// \brief Diagnose function specifiers on a declaration of an identifier that 1986/// does not identify a function. 1987void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1988 // FIXME: We should probably indicate the identifier in question to avoid 1989 // confusion for constructs like "inline int a(), b;" 1990 if (D.getDeclSpec().isInlineSpecified()) 1991 Diag(D.getDeclSpec().getInlineSpecLoc(), 1992 diag::err_inline_non_function); 1993 1994 if (D.getDeclSpec().isVirtualSpecified()) 1995 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1996 diag::err_virtual_non_function); 1997 1998 if (D.getDeclSpec().isExplicitSpecified()) 1999 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2000 diag::err_explicit_non_function); 2001} 2002 2003NamedDecl* 2004Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2005 QualType R, DeclaratorInfo *DInfo, 2006 NamedDecl* PrevDecl, bool &Redeclaration) { 2007 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2008 if (D.getCXXScopeSpec().isSet()) { 2009 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2010 << D.getCXXScopeSpec().getRange(); 2011 D.setInvalidType(); 2012 // Pretend we didn't see the scope specifier. 2013 DC = 0; 2014 } 2015 2016 if (getLangOptions().CPlusPlus) { 2017 // Check that there are no default arguments (C++ only). 2018 CheckExtraCXXDefaultArguments(D); 2019 } 2020 2021 DiagnoseFunctionSpecifiers(D); 2022 2023 if (D.getDeclSpec().isThreadSpecified()) 2024 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2025 2026 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 2027 if (!NewTD) return 0; 2028 2029 // Handle attributes prior to checking for duplicates in MergeVarDecl 2030 ProcessDeclAttributes(S, NewTD, D); 2031 // Merge the decl with the existing one if appropriate. If the decl is 2032 // in an outer scope, it isn't the same thing. 2033 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2034 Redeclaration = true; 2035 MergeTypeDefDecl(NewTD, PrevDecl); 2036 } 2037 2038 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2039 // then it shall have block scope. 2040 QualType T = NewTD->getUnderlyingType(); 2041 if (T->isVariablyModifiedType()) { 2042 CurFunctionNeedsScopeChecking = true; 2043 2044 if (S->getFnParent() == 0) { 2045 bool SizeIsNegative; 2046 QualType FixedTy = 2047 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2048 if (!FixedTy.isNull()) { 2049 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2050 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2051 } else { 2052 if (SizeIsNegative) 2053 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2054 else if (T->isVariableArrayType()) 2055 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2056 else 2057 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2058 NewTD->setInvalidDecl(); 2059 } 2060 } 2061 } 2062 2063 // If this is the C FILE type, notify the AST context. 2064 if (IdentifierInfo *II = NewTD->getIdentifier()) 2065 if (!NewTD->isInvalidDecl() && 2066 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2067 if (II->isStr("FILE")) 2068 Context.setFILEDecl(NewTD); 2069 else if (II->isStr("jmp_buf")) 2070 Context.setjmp_bufDecl(NewTD); 2071 else if (II->isStr("sigjmp_buf")) 2072 Context.setsigjmp_bufDecl(NewTD); 2073 } 2074 2075 return NewTD; 2076} 2077 2078/// \brief Determines whether the given declaration is an out-of-scope 2079/// previous declaration. 2080/// 2081/// This routine should be invoked when name lookup has found a 2082/// previous declaration (PrevDecl) that is not in the scope where a 2083/// new declaration by the same name is being introduced. If the new 2084/// declaration occurs in a local scope, previous declarations with 2085/// linkage may still be considered previous declarations (C99 2086/// 6.2.2p4-5, C++ [basic.link]p6). 2087/// 2088/// \param PrevDecl the previous declaration found by name 2089/// lookup 2090/// 2091/// \param DC the context in which the new declaration is being 2092/// declared. 2093/// 2094/// \returns true if PrevDecl is an out-of-scope previous declaration 2095/// for a new delcaration with the same name. 2096static bool 2097isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2098 ASTContext &Context) { 2099 if (!PrevDecl) 2100 return 0; 2101 2102 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2103 // case we need to check each of the overloaded functions. 2104 if (!PrevDecl->hasLinkage()) 2105 return false; 2106 2107 if (Context.getLangOptions().CPlusPlus) { 2108 // C++ [basic.link]p6: 2109 // If there is a visible declaration of an entity with linkage 2110 // having the same name and type, ignoring entities declared 2111 // outside the innermost enclosing namespace scope, the block 2112 // scope declaration declares that same entity and receives the 2113 // linkage of the previous declaration. 2114 DeclContext *OuterContext = DC->getLookupContext(); 2115 if (!OuterContext->isFunctionOrMethod()) 2116 // This rule only applies to block-scope declarations. 2117 return false; 2118 else { 2119 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2120 if (PrevOuterContext->isRecord()) 2121 // We found a member function: ignore it. 2122 return false; 2123 else { 2124 // Find the innermost enclosing namespace for the new and 2125 // previous declarations. 2126 while (!OuterContext->isFileContext()) 2127 OuterContext = OuterContext->getParent(); 2128 while (!PrevOuterContext->isFileContext()) 2129 PrevOuterContext = PrevOuterContext->getParent(); 2130 2131 // The previous declaration is in a different namespace, so it 2132 // isn't the same function. 2133 if (OuterContext->getPrimaryContext() != 2134 PrevOuterContext->getPrimaryContext()) 2135 return false; 2136 } 2137 } 2138 } 2139 2140 return true; 2141} 2142 2143NamedDecl* 2144Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2145 QualType R, DeclaratorInfo *DInfo, 2146 NamedDecl* PrevDecl, 2147 MultiTemplateParamsArg TemplateParamLists, 2148 bool &Redeclaration) { 2149 DeclarationName Name = GetNameForDeclarator(D); 2150 2151 // Check that there are no default arguments (C++ only). 2152 if (getLangOptions().CPlusPlus) 2153 CheckExtraCXXDefaultArguments(D); 2154 2155 VarDecl *NewVD; 2156 VarDecl::StorageClass SC; 2157 switch (D.getDeclSpec().getStorageClassSpec()) { 2158 default: assert(0 && "Unknown storage class!"); 2159 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2160 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2161 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2162 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2163 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2164 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2165 case DeclSpec::SCS_mutable: 2166 // mutable can only appear on non-static class members, so it's always 2167 // an error here 2168 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2169 D.setInvalidType(); 2170 SC = VarDecl::None; 2171 break; 2172 } 2173 2174 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2175 if (!II) { 2176 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2177 << Name.getAsString(); 2178 return 0; 2179 } 2180 2181 DiagnoseFunctionSpecifiers(D); 2182 2183 if (!DC->isRecord() && S->getFnParent() == 0) { 2184 // C99 6.9p2: The storage-class specifiers auto and register shall not 2185 // appear in the declaration specifiers in an external declaration. 2186 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2187 2188 // If this is a register variable with an asm label specified, then this 2189 // is a GNU extension. 2190 if (SC == VarDecl::Register && D.getAsmLabel()) 2191 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2192 else 2193 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2194 D.setInvalidType(); 2195 } 2196 } 2197 if (DC->isRecord() && !CurContext->isRecord()) { 2198 // This is an out-of-line definition of a static data member. 2199 if (SC == VarDecl::Static) { 2200 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2201 diag::err_static_out_of_line) 2202 << CodeModificationHint::CreateRemoval( 2203 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2204 } else if (SC == VarDecl::None) 2205 SC = VarDecl::Static; 2206 } 2207 if (SC == VarDecl::Static) { 2208 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2209 if (RD->isLocalClass()) 2210 Diag(D.getIdentifierLoc(), 2211 diag::err_static_data_member_not_allowed_in_local_class) 2212 << Name << RD->getDeclName(); 2213 } 2214 } 2215 2216 // Match up the template parameter lists with the scope specifier, then 2217 // determine whether we have a template or a template specialization. 2218 bool isExplicitSpecialization = false; 2219 if (TemplateParameterList *TemplateParams 2220 = MatchTemplateParametersToScopeSpecifier( 2221 D.getDeclSpec().getSourceRange().getBegin(), 2222 D.getCXXScopeSpec(), 2223 (TemplateParameterList**)TemplateParamLists.get(), 2224 TemplateParamLists.size(), 2225 isExplicitSpecialization)) { 2226 if (TemplateParams->size() > 0) { 2227 // There is no such thing as a variable template. 2228 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2229 << II 2230 << SourceRange(TemplateParams->getTemplateLoc(), 2231 TemplateParams->getRAngleLoc()); 2232 return 0; 2233 } else { 2234 // There is an extraneous 'template<>' for this variable. Complain 2235 // about it, but allow the declaration of the variable. 2236 Diag(TemplateParams->getTemplateLoc(), 2237 diag::err_template_variable_noparams) 2238 << II 2239 << SourceRange(TemplateParams->getTemplateLoc(), 2240 TemplateParams->getRAngleLoc()); 2241 2242 isExplicitSpecialization = true; 2243 } 2244 } 2245 2246 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2247 II, R, DInfo, SC); 2248 2249 if (D.isInvalidType()) 2250 NewVD->setInvalidDecl(); 2251 2252 if (D.getDeclSpec().isThreadSpecified()) { 2253 if (NewVD->hasLocalStorage()) 2254 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2255 else if (!Context.Target.isTLSSupported()) 2256 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2257 else 2258 NewVD->setThreadSpecified(true); 2259 } 2260 2261 // Set the lexical context. If the declarator has a C++ scope specifier, the 2262 // lexical context will be different from the semantic context. 2263 NewVD->setLexicalDeclContext(CurContext); 2264 2265 // Handle attributes prior to checking for duplicates in MergeVarDecl 2266 ProcessDeclAttributes(S, NewVD, D); 2267 2268 // Handle GNU asm-label extension (encoded as an attribute). 2269 if (Expr *E = (Expr*) D.getAsmLabel()) { 2270 // The parser guarantees this is a string. 2271 StringLiteral *SE = cast<StringLiteral>(E); 2272 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2273 SE->getByteLength()))); 2274 } 2275 2276 // If name lookup finds a previous declaration that is not in the 2277 // same scope as the new declaration, this may still be an 2278 // acceptable redeclaration. 2279 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2280 !(NewVD->hasLinkage() && 2281 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2282 PrevDecl = 0; 2283 2284 // Merge the decl with the existing one if appropriate. 2285 if (PrevDecl) { 2286 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2287 // The user tried to define a non-static data member 2288 // out-of-line (C++ [dcl.meaning]p1). 2289 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2290 << D.getCXXScopeSpec().getRange(); 2291 PrevDecl = 0; 2292 NewVD->setInvalidDecl(); 2293 } 2294 } else if (D.getCXXScopeSpec().isSet()) { 2295 // No previous declaration in the qualifying scope. 2296 Diag(D.getIdentifierLoc(), diag::err_no_member) 2297 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2298 << D.getCXXScopeSpec().getRange(); 2299 NewVD->setInvalidDecl(); 2300 } 2301 2302 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2303 2304 // This is an explicit specialization of a static data member. Check it. 2305 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2306 CheckMemberSpecialization(NewVD, PrevDecl)) 2307 NewVD->setInvalidDecl(); 2308 2309 // attributes declared post-definition are currently ignored 2310 if (PrevDecl) { 2311 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2312 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2313 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2314 Diag(Def->getLocation(), diag::note_previous_definition); 2315 } 2316 } 2317 2318 // If this is a locally-scoped extern C variable, update the map of 2319 // such variables. 2320 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2321 !NewVD->isInvalidDecl()) 2322 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2323 2324 return NewVD; 2325} 2326 2327/// \brief Perform semantic checking on a newly-created variable 2328/// declaration. 2329/// 2330/// This routine performs all of the type-checking required for a 2331/// variable declaration once it has been built. It is used both to 2332/// check variables after they have been parsed and their declarators 2333/// have been translated into a declaration, and to check variables 2334/// that have been instantiated from a template. 2335/// 2336/// Sets NewVD->isInvalidDecl() if an error was encountered. 2337void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2338 bool &Redeclaration) { 2339 // If the decl is already known invalid, don't check it. 2340 if (NewVD->isInvalidDecl()) 2341 return; 2342 2343 QualType T = NewVD->getType(); 2344 2345 if (T->isObjCInterfaceType()) { 2346 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2347 return NewVD->setInvalidDecl(); 2348 } 2349 2350 // The variable can not have an abstract class type. 2351 if (RequireNonAbstractType(NewVD->getLocation(), T, 2352 diag::err_abstract_type_in_decl, 2353 AbstractVariableType)) 2354 return NewVD->setInvalidDecl(); 2355 2356 // Emit an error if an address space was applied to decl with local storage. 2357 // This includes arrays of objects with address space qualifiers, but not 2358 // automatic variables that point to other address spaces. 2359 // ISO/IEC TR 18037 S5.1.2 2360 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2361 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2362 return NewVD->setInvalidDecl(); 2363 } 2364 2365 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2366 && !NewVD->hasAttr<BlocksAttr>()) 2367 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2368 2369 bool isVM = T->isVariablyModifiedType(); 2370 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2371 NewVD->hasAttr<BlocksAttr>()) 2372 CurFunctionNeedsScopeChecking = true; 2373 2374 if ((isVM && NewVD->hasLinkage()) || 2375 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2376 bool SizeIsNegative; 2377 QualType FixedTy = 2378 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2379 2380 if (FixedTy.isNull() && T->isVariableArrayType()) { 2381 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2382 // FIXME: This won't give the correct result for 2383 // int a[10][n]; 2384 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2385 2386 if (NewVD->isFileVarDecl()) 2387 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2388 << SizeRange; 2389 else if (NewVD->getStorageClass() == VarDecl::Static) 2390 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2391 << SizeRange; 2392 else 2393 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2394 << SizeRange; 2395 return NewVD->setInvalidDecl(); 2396 } 2397 2398 if (FixedTy.isNull()) { 2399 if (NewVD->isFileVarDecl()) 2400 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2401 else 2402 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2403 return NewVD->setInvalidDecl(); 2404 } 2405 2406 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2407 NewVD->setType(FixedTy); 2408 } 2409 2410 if (!PrevDecl && NewVD->isExternC()) { 2411 // Since we did not find anything by this name and we're declaring 2412 // an extern "C" variable, look for a non-visible extern "C" 2413 // declaration with the same name. 2414 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2415 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2416 if (Pos != LocallyScopedExternalDecls.end()) 2417 PrevDecl = Pos->second; 2418 } 2419 2420 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2421 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2422 << T; 2423 return NewVD->setInvalidDecl(); 2424 } 2425 2426 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2427 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2428 return NewVD->setInvalidDecl(); 2429 } 2430 2431 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2432 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2433 return NewVD->setInvalidDecl(); 2434 } 2435 2436 if (PrevDecl) { 2437 Redeclaration = true; 2438 MergeVarDecl(NewVD, PrevDecl); 2439 } 2440} 2441 2442static bool isUsingDecl(Decl *D) { 2443 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2444} 2445 2446/// \brief Data used with FindOverriddenMethod 2447struct FindOverriddenMethodData { 2448 Sema *S; 2449 CXXMethodDecl *Method; 2450}; 2451 2452/// \brief Member lookup function that determines whether a given C++ 2453/// method overrides a method in a base class, to be used with 2454/// CXXRecordDecl::lookupInBases(). 2455static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2456 CXXBasePath &Path, 2457 void *UserData) { 2458 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2459 2460 FindOverriddenMethodData *Data 2461 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2462 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2463 Path.Decls.first != Path.Decls.second; 2464 ++Path.Decls.first) { 2465 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2466 OverloadedFunctionDecl::function_iterator MatchedDecl; 2467 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2468 return true; 2469 } 2470 } 2471 2472 return false; 2473} 2474 2475NamedDecl* 2476Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2477 QualType R, DeclaratorInfo *DInfo, 2478 NamedDecl* PrevDecl, 2479 MultiTemplateParamsArg TemplateParamLists, 2480 bool IsFunctionDefinition, bool &Redeclaration) { 2481 assert(R.getTypePtr()->isFunctionType()); 2482 2483 DeclarationName Name = GetNameForDeclarator(D); 2484 FunctionDecl::StorageClass SC = FunctionDecl::None; 2485 switch (D.getDeclSpec().getStorageClassSpec()) { 2486 default: assert(0 && "Unknown storage class!"); 2487 case DeclSpec::SCS_auto: 2488 case DeclSpec::SCS_register: 2489 case DeclSpec::SCS_mutable: 2490 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2491 diag::err_typecheck_sclass_func); 2492 D.setInvalidType(); 2493 break; 2494 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2495 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2496 case DeclSpec::SCS_static: { 2497 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2498 // C99 6.7.1p5: 2499 // The declaration of an identifier for a function that has 2500 // block scope shall have no explicit storage-class specifier 2501 // other than extern 2502 // See also (C++ [dcl.stc]p4). 2503 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2504 diag::err_static_block_func); 2505 SC = FunctionDecl::None; 2506 } else 2507 SC = FunctionDecl::Static; 2508 break; 2509 } 2510 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2511 } 2512 2513 if (D.getDeclSpec().isThreadSpecified()) 2514 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2515 2516 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2517 bool isInline = D.getDeclSpec().isInlineSpecified(); 2518 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2519 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2520 2521 // Check that the return type is not an abstract class type. 2522 // For record types, this is done by the AbstractClassUsageDiagnoser once 2523 // the class has been completely parsed. 2524 if (!DC->isRecord() && 2525 RequireNonAbstractType(D.getIdentifierLoc(), 2526 R->getAs<FunctionType>()->getResultType(), 2527 diag::err_abstract_type_in_decl, 2528 AbstractReturnType)) 2529 D.setInvalidType(); 2530 2531 // Do not allow returning a objc interface by-value. 2532 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2533 Diag(D.getIdentifierLoc(), 2534 diag::err_object_cannot_be_passed_returned_by_value) << 0 2535 << R->getAs<FunctionType>()->getResultType(); 2536 D.setInvalidType(); 2537 } 2538 2539 bool isVirtualOkay = false; 2540 FunctionDecl *NewFD; 2541 2542 if (isFriend) { 2543 // DC is the namespace in which the function is being declared. 2544 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2545 "friend function being created in a non-namespace context"); 2546 2547 // C++ [class.friend]p5 2548 // A function can be defined in a friend declaration of a 2549 // class . . . . Such a function is implicitly inline. 2550 isInline |= IsFunctionDefinition; 2551 } 2552 2553 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2554 // This is a C++ constructor declaration. 2555 assert(DC->isRecord() && 2556 "Constructors can only be declared in a member context"); 2557 2558 R = CheckConstructorDeclarator(D, R, SC); 2559 2560 // Create the new declaration 2561 NewFD = CXXConstructorDecl::Create(Context, 2562 cast<CXXRecordDecl>(DC), 2563 D.getIdentifierLoc(), Name, R, DInfo, 2564 isExplicit, isInline, 2565 /*isImplicitlyDeclared=*/false); 2566 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2567 // This is a C++ destructor declaration. 2568 if (DC->isRecord()) { 2569 R = CheckDestructorDeclarator(D, SC); 2570 2571 NewFD = CXXDestructorDecl::Create(Context, 2572 cast<CXXRecordDecl>(DC), 2573 D.getIdentifierLoc(), Name, R, 2574 isInline, 2575 /*isImplicitlyDeclared=*/false); 2576 2577 isVirtualOkay = true; 2578 } else { 2579 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2580 2581 // Create a FunctionDecl to satisfy the function definition parsing 2582 // code path. 2583 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2584 Name, R, DInfo, SC, isInline, 2585 /*hasPrototype=*/true); 2586 D.setInvalidType(); 2587 } 2588 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2589 if (!DC->isRecord()) { 2590 Diag(D.getIdentifierLoc(), 2591 diag::err_conv_function_not_member); 2592 return 0; 2593 } 2594 2595 CheckConversionDeclarator(D, R, SC); 2596 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2597 D.getIdentifierLoc(), Name, R, DInfo, 2598 isInline, isExplicit); 2599 2600 isVirtualOkay = true; 2601 } else if (DC->isRecord()) { 2602 // If the of the function is the same as the name of the record, then this 2603 // must be an invalid constructor that has a return type. 2604 // (The parser checks for a return type and makes the declarator a 2605 // constructor if it has no return type). 2606 // must have an invalid constructor that has a return type 2607 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2608 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2609 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2610 << SourceRange(D.getIdentifierLoc()); 2611 return 0; 2612 } 2613 2614 bool isStatic = SC == FunctionDecl::Static; 2615 2616 // [class.free]p1: 2617 // Any allocation function for a class T is a static member 2618 // (even if not explicitly declared static). 2619 if (Name.getCXXOverloadedOperator() == OO_New || 2620 Name.getCXXOverloadedOperator() == OO_Array_New) 2621 isStatic = true; 2622 2623 // [class.free]p6 Any deallocation function for a class X is a static member 2624 // (even if not explicitly declared static). 2625 if (Name.getCXXOverloadedOperator() == OO_Delete || 2626 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2627 isStatic = true; 2628 2629 // This is a C++ method declaration. 2630 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2631 D.getIdentifierLoc(), Name, R, DInfo, 2632 isStatic, isInline); 2633 2634 isVirtualOkay = !isStatic; 2635 } else { 2636 // Determine whether the function was written with a 2637 // prototype. This true when: 2638 // - we're in C++ (where every function has a prototype), 2639 // - there is a prototype in the declarator, or 2640 // - the type R of the function is some kind of typedef or other reference 2641 // to a type name (which eventually refers to a function type). 2642 bool HasPrototype = 2643 getLangOptions().CPlusPlus || 2644 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2645 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2646 2647 NewFD = FunctionDecl::Create(Context, DC, 2648 D.getIdentifierLoc(), 2649 Name, R, DInfo, SC, isInline, HasPrototype); 2650 } 2651 2652 if (D.isInvalidType()) 2653 NewFD->setInvalidDecl(); 2654 2655 // Set the lexical context. If the declarator has a C++ 2656 // scope specifier, or is the object of a friend declaration, the 2657 // lexical context will be different from the semantic context. 2658 NewFD->setLexicalDeclContext(CurContext); 2659 2660 // Match up the template parameter lists with the scope specifier, then 2661 // determine whether we have a template or a template specialization. 2662 FunctionTemplateDecl *FunctionTemplate = 0; 2663 bool isExplicitSpecialization = false; 2664 bool isFunctionTemplateSpecialization = false; 2665 if (TemplateParameterList *TemplateParams 2666 = MatchTemplateParametersToScopeSpecifier( 2667 D.getDeclSpec().getSourceRange().getBegin(), 2668 D.getCXXScopeSpec(), 2669 (TemplateParameterList**)TemplateParamLists.get(), 2670 TemplateParamLists.size(), 2671 isExplicitSpecialization)) { 2672 if (TemplateParams->size() > 0) { 2673 // This is a function template 2674 2675 // Check that we can declare a template here. 2676 if (CheckTemplateDeclScope(S, TemplateParams)) 2677 return 0; 2678 2679 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2680 NewFD->getLocation(), 2681 Name, TemplateParams, 2682 NewFD); 2683 FunctionTemplate->setLexicalDeclContext(CurContext); 2684 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2685 } else { 2686 // This is a function template specialization. 2687 isFunctionTemplateSpecialization = true; 2688 } 2689 2690 // FIXME: Free this memory properly. 2691 TemplateParamLists.release(); 2692 } 2693 2694 // C++ [dcl.fct.spec]p5: 2695 // The virtual specifier shall only be used in declarations of 2696 // nonstatic class member functions that appear within a 2697 // member-specification of a class declaration; see 10.3. 2698 // 2699 if (isVirtual && !NewFD->isInvalidDecl()) { 2700 if (!isVirtualOkay) { 2701 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2702 diag::err_virtual_non_function); 2703 } else if (!CurContext->isRecord()) { 2704 // 'virtual' was specified outside of the class. 2705 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2706 << CodeModificationHint::CreateRemoval( 2707 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2708 } else { 2709 // Okay: Add virtual to the method. 2710 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2711 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2712 CurClass->setAggregate(false); 2713 CurClass->setPOD(false); 2714 CurClass->setEmpty(false); 2715 CurClass->setPolymorphic(true); 2716 CurClass->setHasTrivialConstructor(false); 2717 CurClass->setHasTrivialCopyConstructor(false); 2718 CurClass->setHasTrivialCopyAssignment(false); 2719 } 2720 } 2721 2722 if (isFriend) { 2723 if (FunctionTemplate) { 2724 FunctionTemplate->setObjectOfFriendDecl( 2725 /* PreviouslyDeclared= */ PrevDecl != NULL); 2726 FunctionTemplate->setAccess(AS_public); 2727 } 2728 else 2729 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2730 2731 NewFD->setAccess(AS_public); 2732 } 2733 2734 2735 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2736 // Look for virtual methods in base classes that this method might override. 2737 CXXBasePaths Paths; 2738 FindOverriddenMethodData Data; 2739 Data.Method = NewMD; 2740 Data.S = this; 2741 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2742 Paths)) { 2743 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2744 E = Paths.found_decls_end(); I != E; ++I) { 2745 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2746 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2747 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2748 NewMD->addOverriddenMethod(OldMD); 2749 } 2750 } 2751 } 2752 } 2753 2754 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2755 !CurContext->isRecord()) { 2756 // C++ [class.static]p1: 2757 // A data or function member of a class may be declared static 2758 // in a class definition, in which case it is a static member of 2759 // the class. 2760 2761 // Complain about the 'static' specifier if it's on an out-of-line 2762 // member function definition. 2763 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2764 diag::err_static_out_of_line) 2765 << CodeModificationHint::CreateRemoval( 2766 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2767 } 2768 2769 // Handle GNU asm-label extension (encoded as an attribute). 2770 if (Expr *E = (Expr*) D.getAsmLabel()) { 2771 // The parser guarantees this is a string. 2772 StringLiteral *SE = cast<StringLiteral>(E); 2773 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2774 SE->getByteLength()))); 2775 } 2776 2777 // Copy the parameter declarations from the declarator D to the function 2778 // declaration NewFD, if they are available. First scavenge them into Params. 2779 llvm::SmallVector<ParmVarDecl*, 16> Params; 2780 if (D.getNumTypeObjects() > 0) { 2781 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2782 2783 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2784 // function that takes no arguments, not a function that takes a 2785 // single void argument. 2786 // We let through "const void" here because Sema::GetTypeForDeclarator 2787 // already checks for that case. 2788 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2789 FTI.ArgInfo[0].Param && 2790 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2791 // Empty arg list, don't push any params. 2792 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2793 2794 // In C++, the empty parameter-type-list must be spelled "void"; a 2795 // typedef of void is not permitted. 2796 if (getLangOptions().CPlusPlus && 2797 Param->getType().getUnqualifiedType() != Context.VoidTy) 2798 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2799 // FIXME: Leaks decl? 2800 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2801 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2802 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2803 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2804 Param->setDeclContext(NewFD); 2805 Params.push_back(Param); 2806 } 2807 } 2808 2809 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2810 // When we're declaring a function with a typedef, typeof, etc as in the 2811 // following example, we'll need to synthesize (unnamed) 2812 // parameters for use in the declaration. 2813 // 2814 // @code 2815 // typedef void fn(int); 2816 // fn f; 2817 // @endcode 2818 2819 // Synthesize a parameter for each argument type. 2820 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2821 AE = FT->arg_type_end(); AI != AE; ++AI) { 2822 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2823 SourceLocation(), 0, 2824 *AI, /*DInfo=*/0, 2825 VarDecl::None, 0); 2826 Param->setImplicit(); 2827 Params.push_back(Param); 2828 } 2829 } else { 2830 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2831 "Should not need args for typedef of non-prototype fn"); 2832 } 2833 // Finally, we know we have the right number of parameters, install them. 2834 NewFD->setParams(Context, Params.data(), Params.size()); 2835 2836 // If name lookup finds a previous declaration that is not in the 2837 // same scope as the new declaration, this may still be an 2838 // acceptable redeclaration. 2839 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2840 !(NewFD->hasLinkage() && 2841 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2842 PrevDecl = 0; 2843 2844 // If the declarator is a template-id, translate the parser's template 2845 // argument list into our AST format. 2846 bool HasExplicitTemplateArgs = false; 2847 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 2848 SourceLocation LAngleLoc, RAngleLoc; 2849 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2850 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2851 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2852 TemplateId->getTemplateArgs(), 2853 TemplateId->NumArgs); 2854 translateTemplateArguments(TemplateArgsPtr, 2855 TemplateArgs); 2856 TemplateArgsPtr.release(); 2857 2858 HasExplicitTemplateArgs = true; 2859 LAngleLoc = TemplateId->LAngleLoc; 2860 RAngleLoc = TemplateId->RAngleLoc; 2861 2862 if (FunctionTemplate) { 2863 // FIXME: Diagnose function template with explicit template 2864 // arguments. 2865 HasExplicitTemplateArgs = false; 2866 } else if (!isFunctionTemplateSpecialization && 2867 !D.getDeclSpec().isFriendSpecified()) { 2868 // We have encountered something that the user meant to be a 2869 // specialization (because it has explicitly-specified template 2870 // arguments) but that was not introduced with a "template<>" (or had 2871 // too few of them). 2872 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2873 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2874 << CodeModificationHint::CreateInsertion( 2875 D.getDeclSpec().getSourceRange().getBegin(), 2876 "template<> "); 2877 isFunctionTemplateSpecialization = true; 2878 } 2879 } 2880 2881 if (isFunctionTemplateSpecialization) { 2882 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2883 LAngleLoc, TemplateArgs.data(), 2884 TemplateArgs.size(), RAngleLoc, 2885 PrevDecl)) 2886 NewFD->setInvalidDecl(); 2887 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2888 CheckMemberSpecialization(NewFD, PrevDecl)) 2889 NewFD->setInvalidDecl(); 2890 2891 // Perform semantic checking on the function declaration. 2892 bool OverloadableAttrRequired = false; // FIXME: HACK! 2893 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2894 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2895 2896 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2897 // An out-of-line member function declaration must also be a 2898 // definition (C++ [dcl.meaning]p1). 2899 // Note that this is not the case for explicit specializations of 2900 // function templates or member functions of class templates, per 2901 // C++ [temp.expl.spec]p2. 2902 if (!IsFunctionDefinition && !isFriend && 2903 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2904 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2905 << D.getCXXScopeSpec().getRange(); 2906 NewFD->setInvalidDecl(); 2907 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2908 // The user tried to provide an out-of-line definition for a 2909 // function that is a member of a class or namespace, but there 2910 // was no such member function declared (C++ [class.mfct]p2, 2911 // C++ [namespace.memdef]p2). For example: 2912 // 2913 // class X { 2914 // void f() const; 2915 // }; 2916 // 2917 // void X::f() { } // ill-formed 2918 // 2919 // Complain about this problem, and attempt to suggest close 2920 // matches (e.g., those that differ only in cv-qualifiers and 2921 // whether the parameter types are references). 2922 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2923 << Name << DC << D.getCXXScopeSpec().getRange(); 2924 NewFD->setInvalidDecl(); 2925 2926 LookupResult Prev; 2927 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2928 assert(!Prev.isAmbiguous() && 2929 "Cannot have an ambiguity in previous-declaration lookup"); 2930 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2931 Func != FuncEnd; ++Func) { 2932 if (isa<FunctionDecl>(*Func) && 2933 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2934 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2935 } 2936 2937 PrevDecl = 0; 2938 } 2939 } 2940 2941 // Handle attributes. We need to have merged decls when handling attributes 2942 // (for example to check for conflicts, etc). 2943 // FIXME: This needs to happen before we merge declarations. Then, 2944 // let attribute merging cope with attribute conflicts. 2945 ProcessDeclAttributes(S, NewFD, D); 2946 2947 // attributes declared post-definition are currently ignored 2948 if (Redeclaration && PrevDecl) { 2949 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2950 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2951 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2952 Diag(Def->getLocation(), diag::note_previous_definition); 2953 } 2954 } 2955 2956 AddKnownFunctionAttributes(NewFD); 2957 2958 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2959 // If a function name is overloadable in C, then every function 2960 // with that name must be marked "overloadable". 2961 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2962 << Redeclaration << NewFD; 2963 if (PrevDecl) 2964 Diag(PrevDecl->getLocation(), 2965 diag::note_attribute_overloadable_prev_overload); 2966 NewFD->addAttr(::new (Context) OverloadableAttr()); 2967 } 2968 2969 // If this is a locally-scoped extern C function, update the 2970 // map of such names. 2971 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2972 && !NewFD->isInvalidDecl()) 2973 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2974 2975 // Set this FunctionDecl's range up to the right paren. 2976 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2977 2978 if (FunctionTemplate && NewFD->isInvalidDecl()) 2979 FunctionTemplate->setInvalidDecl(); 2980 2981 if (FunctionTemplate) 2982 return FunctionTemplate; 2983 2984 return NewFD; 2985} 2986 2987/// \brief Perform semantic checking of a new function declaration. 2988/// 2989/// Performs semantic analysis of the new function declaration 2990/// NewFD. This routine performs all semantic checking that does not 2991/// require the actual declarator involved in the declaration, and is 2992/// used both for the declaration of functions as they are parsed 2993/// (called via ActOnDeclarator) and for the declaration of functions 2994/// that have been instantiated via C++ template instantiation (called 2995/// via InstantiateDecl). 2996/// 2997/// \param IsExplicitSpecialiation whether this new function declaration is 2998/// an explicit specialization of the previous declaration. 2999/// 3000/// This sets NewFD->isInvalidDecl() to true if there was an error. 3001void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 3002 bool IsExplicitSpecialization, 3003 bool &Redeclaration, 3004 bool &OverloadableAttrRequired) { 3005 // If NewFD is already known erroneous, don't do any of this checking. 3006 if (NewFD->isInvalidDecl()) 3007 return; 3008 3009 if (NewFD->getResultType()->isVariablyModifiedType()) { 3010 // Functions returning a variably modified type violate C99 6.7.5.2p2 3011 // because all functions have linkage. 3012 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3013 return NewFD->setInvalidDecl(); 3014 } 3015 3016 if (NewFD->isMain()) 3017 CheckMain(NewFD); 3018 3019 // Check for a previous declaration of this name. 3020 if (!PrevDecl && NewFD->isExternC()) { 3021 // Since we did not find anything by this name and we're declaring 3022 // an extern "C" function, look for a non-visible extern "C" 3023 // declaration with the same name. 3024 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3025 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3026 if (Pos != LocallyScopedExternalDecls.end()) 3027 PrevDecl = Pos->second; 3028 } 3029 3030 // Merge or overload the declaration with an existing declaration of 3031 // the same name, if appropriate. 3032 if (PrevDecl) { 3033 // Determine whether NewFD is an overload of PrevDecl or 3034 // a declaration that requires merging. If it's an overload, 3035 // there's no more work to do here; we'll just add the new 3036 // function to the scope. 3037 OverloadedFunctionDecl::function_iterator MatchedDecl; 3038 3039 if (!getLangOptions().CPlusPlus && 3040 AllowOverloadingOfFunction(PrevDecl, Context)) { 3041 OverloadableAttrRequired = true; 3042 3043 // Functions marked "overloadable" must have a prototype (that 3044 // we can't get through declaration merging). 3045 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3046 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3047 << NewFD; 3048 Redeclaration = true; 3049 3050 // Turn this into a variadic function with no parameters. 3051 QualType R = Context.getFunctionType( 3052 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3053 0, 0, true, 0); 3054 NewFD->setType(R); 3055 return NewFD->setInvalidDecl(); 3056 } 3057 } 3058 3059 if (PrevDecl && 3060 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3061 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3062 Redeclaration = true; 3063 Decl *OldDecl = PrevDecl; 3064 3065 // If PrevDecl was an overloaded function, extract the 3066 // FunctionDecl that matched. 3067 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3068 OldDecl = *MatchedDecl; 3069 3070 // NewFD and OldDecl represent declarations that need to be 3071 // merged. 3072 if (MergeFunctionDecl(NewFD, OldDecl)) 3073 return NewFD->setInvalidDecl(); 3074 3075 if (FunctionTemplateDecl *OldTemplateDecl 3076 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3077 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3078 FunctionTemplateDecl *NewTemplateDecl 3079 = NewFD->getDescribedFunctionTemplate(); 3080 assert(NewTemplateDecl && "Template/non-template mismatch"); 3081 if (CXXMethodDecl *Method 3082 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3083 Method->setAccess(OldTemplateDecl->getAccess()); 3084 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3085 } 3086 3087 // If this is an explicit specialization of a member that is a function 3088 // template, mark it as a member specialization. 3089 if (IsExplicitSpecialization && 3090 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3091 NewTemplateDecl->setMemberSpecialization(); 3092 assert(OldTemplateDecl->isMemberSpecialization()); 3093 } 3094 } else { 3095 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3096 NewFD->setAccess(OldDecl->getAccess()); 3097 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3098 } 3099 } 3100 } 3101 3102 // Semantic checking for this function declaration (in isolation). 3103 if (getLangOptions().CPlusPlus) { 3104 // C++-specific checks. 3105 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3106 CheckConstructor(Constructor); 3107 } else if (CXXDestructorDecl *Destructor = 3108 dyn_cast<CXXDestructorDecl>(NewFD)) { 3109 CXXRecordDecl *Record = Destructor->getParent(); 3110 QualType ClassType = Context.getTypeDeclType(Record); 3111 3112 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3113 // type is dependent? Both gcc and edg can handle that. 3114 if (!ClassType->isDependentType()) { 3115 DeclarationName Name 3116 = Context.DeclarationNames.getCXXDestructorName( 3117 Context.getCanonicalType(ClassType)); 3118 if (NewFD->getDeclName() != Name) { 3119 Diag(NewFD->getLocation(), diag::err_destructor_name); 3120 return NewFD->setInvalidDecl(); 3121 } 3122 3123 CheckDestructor(Destructor); 3124 } 3125 3126 Record->setUserDeclaredDestructor(true); 3127 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3128 // user-defined destructor. 3129 Record->setPOD(false); 3130 3131 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3132 // declared destructor. 3133 // FIXME: C++0x: don't do this for "= default" destructors 3134 Record->setHasTrivialDestructor(false); 3135 } else if (CXXConversionDecl *Conversion 3136 = dyn_cast<CXXConversionDecl>(NewFD)) 3137 ActOnConversionDeclarator(Conversion); 3138 3139 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3140 if (NewFD->isOverloadedOperator() && 3141 CheckOverloadedOperatorDeclaration(NewFD)) 3142 return NewFD->setInvalidDecl(); 3143 3144 // In C++, check default arguments now that we have merged decls. Unless 3145 // the lexical context is the class, because in this case this is done 3146 // during delayed parsing anyway. 3147 if (!CurContext->isRecord()) 3148 CheckCXXDefaultArguments(NewFD); 3149 } 3150} 3151 3152void Sema::CheckMain(FunctionDecl* FD) { 3153 // C++ [basic.start.main]p3: A program that declares main to be inline 3154 // or static is ill-formed. 3155 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3156 // shall not appear in a declaration of main. 3157 // static main is not an error under C99, but we should warn about it. 3158 bool isInline = FD->isInlineSpecified(); 3159 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3160 if (isInline || isStatic) { 3161 unsigned diagID = diag::warn_unusual_main_decl; 3162 if (isInline || getLangOptions().CPlusPlus) 3163 diagID = diag::err_unusual_main_decl; 3164 3165 int which = isStatic + (isInline << 1) - 1; 3166 Diag(FD->getLocation(), diagID) << which; 3167 } 3168 3169 QualType T = FD->getType(); 3170 assert(T->isFunctionType() && "function decl is not of function type"); 3171 const FunctionType* FT = T->getAs<FunctionType>(); 3172 3173 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3174 // TODO: add a replacement fixit to turn the return type into 'int'. 3175 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3176 FD->setInvalidDecl(true); 3177 } 3178 3179 // Treat protoless main() as nullary. 3180 if (isa<FunctionNoProtoType>(FT)) return; 3181 3182 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3183 unsigned nparams = FTP->getNumArgs(); 3184 assert(FD->getNumParams() == nparams); 3185 3186 if (nparams > 3) { 3187 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3188 FD->setInvalidDecl(true); 3189 nparams = 3; 3190 } 3191 3192 // FIXME: a lot of the following diagnostics would be improved 3193 // if we had some location information about types. 3194 3195 QualType CharPP = 3196 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3197 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3198 3199 for (unsigned i = 0; i < nparams; ++i) { 3200 QualType AT = FTP->getArgType(i); 3201 3202 bool mismatch = true; 3203 3204 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3205 mismatch = false; 3206 else if (Expected[i] == CharPP) { 3207 // As an extension, the following forms are okay: 3208 // char const ** 3209 // char const * const * 3210 // char * const * 3211 3212 QualifierCollector qs; 3213 const PointerType* PT; 3214 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3215 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3216 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3217 qs.removeConst(); 3218 mismatch = !qs.empty(); 3219 } 3220 } 3221 3222 if (mismatch) { 3223 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3224 // TODO: suggest replacing given type with expected type 3225 FD->setInvalidDecl(true); 3226 } 3227 } 3228 3229 if (nparams == 1 && !FD->isInvalidDecl()) { 3230 Diag(FD->getLocation(), diag::warn_main_one_arg); 3231 } 3232} 3233 3234bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3235 // FIXME: Need strict checking. In C89, we need to check for 3236 // any assignment, increment, decrement, function-calls, or 3237 // commas outside of a sizeof. In C99, it's the same list, 3238 // except that the aforementioned are allowed in unevaluated 3239 // expressions. Everything else falls under the 3240 // "may accept other forms of constant expressions" exception. 3241 // (We never end up here for C++, so the constant expression 3242 // rules there don't matter.) 3243 if (Init->isConstantInitializer(Context)) 3244 return false; 3245 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3246 << Init->getSourceRange(); 3247 return true; 3248} 3249 3250void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3251 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3252} 3253 3254/// AddInitializerToDecl - Adds the initializer Init to the 3255/// declaration dcl. If DirectInit is true, this is C++ direct 3256/// initialization rather than copy initialization. 3257void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3258 Decl *RealDecl = dcl.getAs<Decl>(); 3259 // If there is no declaration, there was an error parsing it. Just ignore 3260 // the initializer. 3261 if (RealDecl == 0) 3262 return; 3263 3264 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3265 // With declarators parsed the way they are, the parser cannot 3266 // distinguish between a normal initializer and a pure-specifier. 3267 // Thus this grotesque test. 3268 IntegerLiteral *IL; 3269 Expr *Init = static_cast<Expr *>(init.get()); 3270 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3271 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3272 if (Method->isVirtualAsWritten()) { 3273 Method->setPure(); 3274 3275 // A class is abstract if at least one function is pure virtual. 3276 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3277 } else if (!Method->isInvalidDecl()) { 3278 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3279 << Method->getDeclName() << Init->getSourceRange(); 3280 Method->setInvalidDecl(); 3281 } 3282 } else { 3283 Diag(Method->getLocation(), diag::err_member_function_initialization) 3284 << Method->getDeclName() << Init->getSourceRange(); 3285 Method->setInvalidDecl(); 3286 } 3287 return; 3288 } 3289 3290 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3291 if (!VDecl) { 3292 if (getLangOptions().CPlusPlus && 3293 RealDecl->getLexicalDeclContext()->isRecord() && 3294 isa<NamedDecl>(RealDecl)) 3295 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3296 << cast<NamedDecl>(RealDecl)->getDeclName(); 3297 else 3298 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3299 RealDecl->setInvalidDecl(); 3300 return; 3301 } 3302 3303 // A definition must end up with a complete type, which means it must be 3304 // complete with the restriction that an array type might be completed by the 3305 // initializer; note that later code assumes this restriction. 3306 QualType BaseDeclType = VDecl->getType(); 3307 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3308 BaseDeclType = Array->getElementType(); 3309 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3310 diag::err_typecheck_decl_incomplete_type)) { 3311 RealDecl->setInvalidDecl(); 3312 return; 3313 } 3314 3315 const VarDecl *Def = 0; 3316 if (VDecl->getDefinition(Def)) { 3317 Diag(VDecl->getLocation(), diag::err_redefinition) 3318 << VDecl->getDeclName(); 3319 Diag(Def->getLocation(), diag::note_previous_definition); 3320 VDecl->setInvalidDecl(); 3321 return; 3322 } 3323 3324 // Take ownership of the expression, now that we're sure we have somewhere 3325 // to put it. 3326 Expr *Init = init.takeAs<Expr>(); 3327 assert(Init && "missing initializer"); 3328 3329 // Get the decls type and save a reference for later, since 3330 // CheckInitializerTypes may change it. 3331 QualType DclT = VDecl->getType(), SavT = DclT; 3332 if (VDecl->isBlockVarDecl()) { 3333 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3334 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3335 VDecl->setInvalidDecl(); 3336 } else if (!VDecl->isInvalidDecl()) { 3337 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3338 VDecl->getDeclName(), DirectInit)) 3339 VDecl->setInvalidDecl(); 3340 3341 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3342 // Don't check invalid declarations to avoid emitting useless diagnostics. 3343 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3344 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3345 CheckForConstantInitializer(Init, DclT); 3346 } 3347 } 3348 } else if (VDecl->isStaticDataMember() && 3349 VDecl->getLexicalDeclContext()->isRecord()) { 3350 // This is an in-class initialization for a static data member, e.g., 3351 // 3352 // struct S { 3353 // static const int value = 17; 3354 // }; 3355 3356 // Attach the initializer 3357 VDecl->setInit(Context, Init); 3358 3359 // C++ [class.mem]p4: 3360 // A member-declarator can contain a constant-initializer only 3361 // if it declares a static member (9.4) of const integral or 3362 // const enumeration type, see 9.4.2. 3363 QualType T = VDecl->getType(); 3364 if (!T->isDependentType() && 3365 (!Context.getCanonicalType(T).isConstQualified() || 3366 !T->isIntegralType())) { 3367 Diag(VDecl->getLocation(), diag::err_member_initialization) 3368 << VDecl->getDeclName() << Init->getSourceRange(); 3369 VDecl->setInvalidDecl(); 3370 } else { 3371 // C++ [class.static.data]p4: 3372 // If a static data member is of const integral or const 3373 // enumeration type, its declaration in the class definition 3374 // can specify a constant-initializer which shall be an 3375 // integral constant expression (5.19). 3376 if (!Init->isTypeDependent() && 3377 !Init->getType()->isIntegralType()) { 3378 // We have a non-dependent, non-integral or enumeration type. 3379 Diag(Init->getSourceRange().getBegin(), 3380 diag::err_in_class_initializer_non_integral_type) 3381 << Init->getType() << Init->getSourceRange(); 3382 VDecl->setInvalidDecl(); 3383 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3384 // Check whether the expression is a constant expression. 3385 llvm::APSInt Value; 3386 SourceLocation Loc; 3387 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3388 Diag(Loc, diag::err_in_class_initializer_non_constant) 3389 << Init->getSourceRange(); 3390 VDecl->setInvalidDecl(); 3391 } else if (!VDecl->getType()->isDependentType()) 3392 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3393 } 3394 } 3395 } else if (VDecl->isFileVarDecl()) { 3396 if (VDecl->getStorageClass() == VarDecl::Extern) 3397 Diag(VDecl->getLocation(), diag::warn_extern_init); 3398 if (!VDecl->isInvalidDecl()) 3399 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3400 VDecl->getDeclName(), DirectInit)) 3401 VDecl->setInvalidDecl(); 3402 3403 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3404 // Don't check invalid declarations to avoid emitting useless diagnostics. 3405 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3406 // C99 6.7.8p4. All file scoped initializers need to be constant. 3407 CheckForConstantInitializer(Init, DclT); 3408 } 3409 } 3410 // If the type changed, it means we had an incomplete type that was 3411 // completed by the initializer. For example: 3412 // int ary[] = { 1, 3, 5 }; 3413 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3414 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3415 VDecl->setType(DclT); 3416 Init->setType(DclT); 3417 } 3418 3419 Init = MaybeCreateCXXExprWithTemporaries(Init, 3420 /*ShouldDestroyTemporaries=*/true); 3421 // Attach the initializer to the decl. 3422 VDecl->setInit(Context, Init); 3423 3424 // If the previous declaration of VDecl was a tentative definition, 3425 // remove it from the set of tentative definitions. 3426 if (VDecl->getPreviousDeclaration() && 3427 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3428 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3429 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3430 } 3431 3432 return; 3433} 3434 3435void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3436 bool TypeContainsUndeducedAuto) { 3437 Decl *RealDecl = dcl.getAs<Decl>(); 3438 3439 // If there is no declaration, there was an error parsing it. Just ignore it. 3440 if (RealDecl == 0) 3441 return; 3442 3443 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3444 QualType Type = Var->getType(); 3445 3446 // Record tentative definitions. 3447 if (Var->isTentativeDefinition(Context)) { 3448 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3449 InsertPair = 3450 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3451 3452 // Keep the latest definition in the map. If we see 'int i; int i;' we 3453 // want the second one in the map. 3454 InsertPair.first->second = Var; 3455 3456 // However, for the list, we don't care about the order, just make sure 3457 // that there are no dupes for a given declaration name. 3458 if (InsertPair.second) 3459 TentativeDefinitionList.push_back(Var->getDeclName()); 3460 } 3461 3462 // C++ [dcl.init.ref]p3: 3463 // The initializer can be omitted for a reference only in a 3464 // parameter declaration (8.3.5), in the declaration of a 3465 // function return type, in the declaration of a class member 3466 // within its class declaration (9.2), and where the extern 3467 // specifier is explicitly used. 3468 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3469 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3470 << Var->getDeclName() 3471 << SourceRange(Var->getLocation(), Var->getLocation()); 3472 Var->setInvalidDecl(); 3473 return; 3474 } 3475 3476 // C++0x [dcl.spec.auto]p3 3477 if (TypeContainsUndeducedAuto) { 3478 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3479 << Var->getDeclName() << Type; 3480 Var->setInvalidDecl(); 3481 return; 3482 } 3483 3484 // An array without size is an incomplete type, and there are no special 3485 // rules in C++ to make such a definition acceptable. 3486 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3487 !Var->hasExternalStorage()) { 3488 Diag(Var->getLocation(), 3489 diag::err_typecheck_incomplete_array_needs_initializer); 3490 Var->setInvalidDecl(); 3491 return; 3492 } 3493 3494 // C++ [temp.expl.spec]p15: 3495 // An explicit specialization of a static data member of a template is a 3496 // definition if the declaration includes an initializer; otherwise, it 3497 // is a declaration. 3498 if (Var->isStaticDataMember() && 3499 Var->getInstantiatedFromStaticDataMember() && 3500 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3501 return; 3502 3503 // C++ [dcl.init]p9: 3504 // If no initializer is specified for an object, and the object 3505 // is of (possibly cv-qualified) non-POD class type (or array 3506 // thereof), the object shall be default-initialized; if the 3507 // object is of const-qualified type, the underlying class type 3508 // shall have a user-declared default constructor. 3509 // 3510 // FIXME: Diagnose the "user-declared default constructor" bit. 3511 if (getLangOptions().CPlusPlus) { 3512 QualType InitType = Type; 3513 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3514 InitType = Context.getBaseElementType(Array); 3515 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3516 InitType->isRecordType() && !InitType->isDependentType()) { 3517 if (!RequireCompleteType(Var->getLocation(), InitType, 3518 diag::err_invalid_incomplete_type_use)) { 3519 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3520 3521 CXXConstructorDecl *Constructor 3522 = PerformInitializationByConstructor(InitType, 3523 MultiExprArg(*this, 0, 0), 3524 Var->getLocation(), 3525 SourceRange(Var->getLocation(), 3526 Var->getLocation()), 3527 Var->getDeclName(), 3528 IK_Default, 3529 ConstructorArgs); 3530 3531 // FIXME: Location info for the variable initialization? 3532 if (!Constructor) 3533 Var->setInvalidDecl(); 3534 else { 3535 // FIXME: Cope with initialization of arrays 3536 if (!Constructor->isTrivial() && 3537 InitializeVarWithConstructor(Var, Constructor, 3538 move_arg(ConstructorArgs))) 3539 Var->setInvalidDecl(); 3540 3541 FinalizeVarWithDestructor(Var, InitType); 3542 } 3543 } else { 3544 Var->setInvalidDecl(); 3545 } 3546 } 3547 } 3548 3549#if 0 3550 // FIXME: Temporarily disabled because we are not properly parsing 3551 // linkage specifications on declarations, e.g., 3552 // 3553 // extern "C" const CGPoint CGPointerZero; 3554 // 3555 // C++ [dcl.init]p9: 3556 // 3557 // If no initializer is specified for an object, and the 3558 // object is of (possibly cv-qualified) non-POD class type (or 3559 // array thereof), the object shall be default-initialized; if 3560 // the object is of const-qualified type, the underlying class 3561 // type shall have a user-declared default 3562 // constructor. Otherwise, if no initializer is specified for 3563 // an object, the object and its subobjects, if any, have an 3564 // indeterminate initial value; if the object or any of its 3565 // subobjects are of const-qualified type, the program is 3566 // ill-formed. 3567 // 3568 // This isn't technically an error in C, so we don't diagnose it. 3569 // 3570 // FIXME: Actually perform the POD/user-defined default 3571 // constructor check. 3572 if (getLangOptions().CPlusPlus && 3573 Context.getCanonicalType(Type).isConstQualified() && 3574 !Var->hasExternalStorage()) 3575 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3576 << Var->getName() 3577 << SourceRange(Var->getLocation(), Var->getLocation()); 3578#endif 3579 } 3580} 3581 3582Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3583 DeclPtrTy *Group, 3584 unsigned NumDecls) { 3585 llvm::SmallVector<Decl*, 8> Decls; 3586 3587 if (DS.isTypeSpecOwned()) 3588 Decls.push_back((Decl*)DS.getTypeRep()); 3589 3590 for (unsigned i = 0; i != NumDecls; ++i) 3591 if (Decl *D = Group[i].getAs<Decl>()) 3592 Decls.push_back(D); 3593 3594 // Perform semantic analysis that depends on having fully processed both 3595 // the declarator and initializer. 3596 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3597 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3598 if (!IDecl) 3599 continue; 3600 QualType T = IDecl->getType(); 3601 3602 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3603 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3604 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3605 if (T->isDependentType()) { 3606 // If T is dependent, we should not require a complete type. 3607 // (RequireCompleteType shouldn't be called with dependent types.) 3608 // But we still can at least check if we've got an array of unspecified 3609 // size without an initializer. 3610 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3611 !IDecl->getInit()) { 3612 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3613 << T; 3614 IDecl->setInvalidDecl(); 3615 } 3616 } else if (!IDecl->isInvalidDecl()) { 3617 // If T is an incomplete array type with an initializer list that is 3618 // dependent on something, its size has not been fixed. We could attempt 3619 // to fix the size for such arrays, but we would still have to check 3620 // here for initializers containing a C++0x vararg expansion, e.g. 3621 // template <typename... Args> void f(Args... args) { 3622 // int vals[] = { args }; 3623 // } 3624 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3625 Expr *Init = IDecl->getInit(); 3626 if (IAT && Init && 3627 (Init->isTypeDependent() || Init->isValueDependent())) { 3628 // Check that the member type of the array is complete, at least. 3629 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3630 diag::err_typecheck_decl_incomplete_type)) 3631 IDecl->setInvalidDecl(); 3632 } else if (RequireCompleteType(IDecl->getLocation(), T, 3633 diag::err_typecheck_decl_incomplete_type)) 3634 IDecl->setInvalidDecl(); 3635 } 3636 } 3637 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3638 // object that has file scope without an initializer, and without a 3639 // storage-class specifier or with the storage-class specifier "static", 3640 // constitutes a tentative definition. Note: A tentative definition with 3641 // external linkage is valid (C99 6.2.2p5). 3642 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3643 if (const IncompleteArrayType *ArrayT 3644 = Context.getAsIncompleteArrayType(T)) { 3645 if (RequireCompleteType(IDecl->getLocation(), 3646 ArrayT->getElementType(), 3647 diag::err_illegal_decl_array_incomplete_type)) 3648 IDecl->setInvalidDecl(); 3649 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3650 // C99 6.9.2p3: If the declaration of an identifier for an object is 3651 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3652 // declared type shall not be an incomplete type. 3653 // NOTE: code such as the following 3654 // static struct s; 3655 // struct s { int a; }; 3656 // is accepted by gcc. Hence here we issue a warning instead of 3657 // an error and we do not invalidate the static declaration. 3658 // NOTE: to avoid multiple warnings, only check the first declaration. 3659 if (IDecl->getPreviousDeclaration() == 0) 3660 RequireCompleteType(IDecl->getLocation(), T, 3661 diag::ext_typecheck_decl_incomplete_type); 3662 } 3663 } 3664 } 3665 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3666 Decls.data(), Decls.size())); 3667} 3668 3669 3670/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3671/// to introduce parameters into function prototype scope. 3672Sema::DeclPtrTy 3673Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3674 const DeclSpec &DS = D.getDeclSpec(); 3675 3676 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3677 VarDecl::StorageClass StorageClass = VarDecl::None; 3678 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3679 StorageClass = VarDecl::Register; 3680 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3681 Diag(DS.getStorageClassSpecLoc(), 3682 diag::err_invalid_storage_class_in_func_decl); 3683 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3684 } 3685 3686 if (D.getDeclSpec().isThreadSpecified()) 3687 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3688 3689 DiagnoseFunctionSpecifiers(D); 3690 3691 // Check that there are no default arguments inside the type of this 3692 // parameter (C++ only). 3693 if (getLangOptions().CPlusPlus) 3694 CheckExtraCXXDefaultArguments(D); 3695 3696 DeclaratorInfo *DInfo = 0; 3697 TagDecl *OwnedDecl = 0; 3698 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3699 3700 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3701 // C++ [dcl.fct]p6: 3702 // Types shall not be defined in return or parameter types. 3703 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3704 << Context.getTypeDeclType(OwnedDecl); 3705 } 3706 3707 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3708 // Can this happen for params? We already checked that they don't conflict 3709 // among each other. Here they can only shadow globals, which is ok. 3710 IdentifierInfo *II = D.getIdentifier(); 3711 if (II) { 3712 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3713 if (PrevDecl->isTemplateParameter()) { 3714 // Maybe we will complain about the shadowed template parameter. 3715 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3716 // Just pretend that we didn't see the previous declaration. 3717 PrevDecl = 0; 3718 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3719 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3720 3721 // Recover by removing the name 3722 II = 0; 3723 D.SetIdentifier(0, D.getIdentifierLoc()); 3724 } 3725 } 3726 } 3727 3728 // Parameters can not be abstract class types. 3729 // For record types, this is done by the AbstractClassUsageDiagnoser once 3730 // the class has been completely parsed. 3731 if (!CurContext->isRecord() && 3732 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3733 diag::err_abstract_type_in_decl, 3734 AbstractParamType)) 3735 D.setInvalidType(true); 3736 3737 QualType T = adjustParameterType(parmDeclType); 3738 3739 ParmVarDecl *New 3740 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3741 T, DInfo, StorageClass, 0); 3742 3743 if (D.isInvalidType()) 3744 New->setInvalidDecl(); 3745 3746 // Parameter declarators cannot be interface types. All ObjC objects are 3747 // passed by reference. 3748 if (T->isObjCInterfaceType()) { 3749 Diag(D.getIdentifierLoc(), 3750 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3751 New->setInvalidDecl(); 3752 } 3753 3754 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3755 if (D.getCXXScopeSpec().isSet()) { 3756 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3757 << D.getCXXScopeSpec().getRange(); 3758 New->setInvalidDecl(); 3759 } 3760 3761 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3762 // duration shall not be qualified by an address-space qualifier." 3763 // Since all parameters have automatic store duration, they can not have 3764 // an address space. 3765 if (T.getAddressSpace() != 0) { 3766 Diag(D.getIdentifierLoc(), 3767 diag::err_arg_with_address_space); 3768 New->setInvalidDecl(); 3769 } 3770 3771 3772 // Add the parameter declaration into this scope. 3773 S->AddDecl(DeclPtrTy::make(New)); 3774 if (II) 3775 IdResolver.AddDecl(New); 3776 3777 ProcessDeclAttributes(S, New, D); 3778 3779 if (New->hasAttr<BlocksAttr>()) { 3780 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3781 } 3782 return DeclPtrTy::make(New); 3783} 3784 3785void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3786 SourceLocation LocAfterDecls) { 3787 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3788 "Not a function declarator!"); 3789 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3790 3791 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3792 // for a K&R function. 3793 if (!FTI.hasPrototype) { 3794 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3795 --i; 3796 if (FTI.ArgInfo[i].Param == 0) { 3797 llvm::SmallString<256> Code; 3798 llvm::raw_svector_ostream(Code) << " int " 3799 << FTI.ArgInfo[i].Ident->getName() 3800 << ";\n"; 3801 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3802 << FTI.ArgInfo[i].Ident 3803 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3804 3805 // Implicitly declare the argument as type 'int' for lack of a better 3806 // type. 3807 DeclSpec DS; 3808 const char* PrevSpec; // unused 3809 unsigned DiagID; // unused 3810 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3811 PrevSpec, DiagID); 3812 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3813 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3814 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3815 } 3816 } 3817 } 3818} 3819 3820Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3821 Declarator &D) { 3822 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3823 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3824 "Not a function declarator!"); 3825 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3826 3827 if (FTI.hasPrototype) { 3828 // FIXME: Diagnose arguments without names in C. 3829 } 3830 3831 Scope *ParentScope = FnBodyScope->getParent(); 3832 3833 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3834 MultiTemplateParamsArg(*this), 3835 /*IsFunctionDefinition=*/true); 3836 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3837} 3838 3839Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3840 // Clear the last template instantiation error context. 3841 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 3842 3843 if (!D) 3844 return D; 3845 FunctionDecl *FD = 0; 3846 3847 if (FunctionTemplateDecl *FunTmpl 3848 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3849 FD = FunTmpl->getTemplatedDecl(); 3850 else 3851 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3852 3853 CurFunctionNeedsScopeChecking = false; 3854 3855 // See if this is a redefinition. 3856 const FunctionDecl *Definition; 3857 if (FD->getBody(Definition)) { 3858 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3859 Diag(Definition->getLocation(), diag::note_previous_definition); 3860 } 3861 3862 // Builtin functions cannot be defined. 3863 if (unsigned BuiltinID = FD->getBuiltinID()) { 3864 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3865 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3866 FD->setInvalidDecl(); 3867 } 3868 } 3869 3870 // The return type of a function definition must be complete 3871 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3872 QualType ResultType = FD->getResultType(); 3873 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3874 !FD->isInvalidDecl() && 3875 RequireCompleteType(FD->getLocation(), ResultType, 3876 diag::err_func_def_incomplete_result)) 3877 FD->setInvalidDecl(); 3878 3879 // GNU warning -Wmissing-prototypes: 3880 // Warn if a global function is defined without a previous 3881 // prototype declaration. This warning is issued even if the 3882 // definition itself provides a prototype. The aim is to detect 3883 // global functions that fail to be declared in header files. 3884 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3885 !FD->isMain()) { 3886 bool MissingPrototype = true; 3887 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3888 Prev; Prev = Prev->getPreviousDeclaration()) { 3889 // Ignore any declarations that occur in function or method 3890 // scope, because they aren't visible from the header. 3891 if (Prev->getDeclContext()->isFunctionOrMethod()) 3892 continue; 3893 3894 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3895 break; 3896 } 3897 3898 if (MissingPrototype) 3899 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3900 } 3901 3902 if (FnBodyScope) 3903 PushDeclContext(FnBodyScope, FD); 3904 3905 // Check the validity of our function parameters 3906 CheckParmsForFunctionDef(FD); 3907 3908 // Introduce our parameters into the function scope 3909 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3910 ParmVarDecl *Param = FD->getParamDecl(p); 3911 Param->setOwningFunction(FD); 3912 3913 // If this has an identifier, add it to the scope stack. 3914 if (Param->getIdentifier() && FnBodyScope) 3915 PushOnScopeChains(Param, FnBodyScope); 3916 } 3917 3918 // Checking attributes of current function definition 3919 // dllimport attribute. 3920 if (FD->getAttr<DLLImportAttr>() && 3921 (!FD->getAttr<DLLExportAttr>())) { 3922 // dllimport attribute cannot be applied to definition. 3923 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3924 Diag(FD->getLocation(), 3925 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3926 << "dllimport"; 3927 FD->setInvalidDecl(); 3928 return DeclPtrTy::make(FD); 3929 } else { 3930 // If a symbol previously declared dllimport is later defined, the 3931 // attribute is ignored in subsequent references, and a warning is 3932 // emitted. 3933 Diag(FD->getLocation(), 3934 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3935 << FD->getNameAsCString() << "dllimport"; 3936 } 3937 } 3938 return DeclPtrTy::make(FD); 3939} 3940 3941Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3942 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3943} 3944 3945Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3946 bool IsInstantiation) { 3947 Decl *dcl = D.getAs<Decl>(); 3948 Stmt *Body = BodyArg.takeAs<Stmt>(); 3949 3950 FunctionDecl *FD = 0; 3951 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3952 if (FunTmpl) 3953 FD = FunTmpl->getTemplatedDecl(); 3954 else 3955 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3956 3957 if (FD) { 3958 FD->setBody(Body); 3959 if (FD->isMain()) 3960 // C and C++ allow for main to automagically return 0. 3961 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3962 FD->setHasImplicitReturnZero(true); 3963 else 3964 CheckFallThroughForFunctionDef(FD, Body); 3965 3966 if (!FD->isInvalidDecl()) 3967 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3968 3969 // C++ [basic.def.odr]p2: 3970 // [...] A virtual member function is used if it is not pure. [...] 3971 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3972 if (Method->isVirtual() && !Method->isPure()) 3973 MarkDeclarationReferenced(Method->getLocation(), Method); 3974 3975 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3976 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3977 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3978 MD->setBody(Body); 3979 CheckFallThroughForFunctionDef(MD, Body); 3980 MD->setEndLoc(Body->getLocEnd()); 3981 3982 if (!MD->isInvalidDecl()) 3983 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3984 } else { 3985 Body->Destroy(Context); 3986 return DeclPtrTy(); 3987 } 3988 if (!IsInstantiation) 3989 PopDeclContext(); 3990 3991 // Verify and clean out per-function state. 3992 3993 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3994 3995 // Check goto/label use. 3996 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3997 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3998 LabelStmt *L = I->second; 3999 4000 // Verify that we have no forward references left. If so, there was a goto 4001 // or address of a label taken, but no definition of it. Label fwd 4002 // definitions are indicated with a null substmt. 4003 if (L->getSubStmt() != 0) 4004 continue; 4005 4006 // Emit error. 4007 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4008 4009 // At this point, we have gotos that use the bogus label. Stitch it into 4010 // the function body so that they aren't leaked and that the AST is well 4011 // formed. 4012 if (Body == 0) { 4013 // The whole function wasn't parsed correctly, just delete this. 4014 L->Destroy(Context); 4015 continue; 4016 } 4017 4018 // Otherwise, the body is valid: we want to stitch the label decl into the 4019 // function somewhere so that it is properly owned and so that the goto 4020 // has a valid target. Do this by creating a new compound stmt with the 4021 // label in it. 4022 4023 // Give the label a sub-statement. 4024 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4025 4026 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4027 cast<CXXTryStmt>(Body)->getTryBlock() : 4028 cast<CompoundStmt>(Body); 4029 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4030 Elements.push_back(L); 4031 Compound->setStmts(Context, &Elements[0], Elements.size()); 4032 } 4033 FunctionLabelMap.clear(); 4034 4035 if (!Body) return D; 4036 4037 // Verify that that gotos and switch cases don't jump into scopes illegally. 4038 if (CurFunctionNeedsScopeChecking) 4039 DiagnoseInvalidJumps(Body); 4040 4041 // C++ constructors that have function-try-blocks can't have return 4042 // statements in the handlers of that block. (C++ [except.handle]p14) 4043 // Verify this. 4044 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4045 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4046 4047 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4048 computeBaseOrMembersToDestroy(Destructor); 4049 4050 // If any errors have occurred, clear out any temporaries that may have 4051 // been leftover. This ensures that these temporaries won't be picked up for 4052 // deletion in some later function. 4053 if (PP.getDiagnostics().hasErrorOccurred()) 4054 ExprTemporaries.clear(); 4055 4056 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4057 return D; 4058} 4059 4060/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4061/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4062NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4063 IdentifierInfo &II, Scope *S) { 4064 // Before we produce a declaration for an implicitly defined 4065 // function, see whether there was a locally-scoped declaration of 4066 // this name as a function or variable. If so, use that 4067 // (non-visible) declaration, and complain about it. 4068 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4069 = LocallyScopedExternalDecls.find(&II); 4070 if (Pos != LocallyScopedExternalDecls.end()) { 4071 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4072 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4073 return Pos->second; 4074 } 4075 4076 // Extension in C99. Legal in C90, but warn about it. 4077 if (II.getName().startswith("__builtin_")) 4078 Diag(Loc, diag::warn_builtin_unknown) << &II; 4079 else if (getLangOptions().C99) 4080 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4081 else 4082 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4083 4084 // Set a Declarator for the implicit definition: int foo(); 4085 const char *Dummy; 4086 DeclSpec DS; 4087 unsigned DiagID; 4088 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4089 Error = Error; // Silence warning. 4090 assert(!Error && "Error setting up implicit decl!"); 4091 Declarator D(DS, Declarator::BlockContext); 4092 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4093 0, 0, false, SourceLocation(), 4094 false, 0,0,0, Loc, Loc, D), 4095 SourceLocation()); 4096 D.SetIdentifier(&II, Loc); 4097 4098 // Insert this function into translation-unit scope. 4099 4100 DeclContext *PrevDC = CurContext; 4101 CurContext = Context.getTranslationUnitDecl(); 4102 4103 FunctionDecl *FD = 4104 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4105 FD->setImplicit(); 4106 4107 CurContext = PrevDC; 4108 4109 AddKnownFunctionAttributes(FD); 4110 4111 return FD; 4112} 4113 4114/// \brief Adds any function attributes that we know a priori based on 4115/// the declaration of this function. 4116/// 4117/// These attributes can apply both to implicitly-declared builtins 4118/// (like __builtin___printf_chk) or to library-declared functions 4119/// like NSLog or printf. 4120void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4121 if (FD->isInvalidDecl()) 4122 return; 4123 4124 // If this is a built-in function, map its builtin attributes to 4125 // actual attributes. 4126 if (unsigned BuiltinID = FD->getBuiltinID()) { 4127 // Handle printf-formatting attributes. 4128 unsigned FormatIdx; 4129 bool HasVAListArg; 4130 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4131 if (!FD->getAttr<FormatAttr>()) 4132 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4133 HasVAListArg ? 0 : FormatIdx + 2)); 4134 } 4135 4136 // Mark const if we don't care about errno and that is the only 4137 // thing preventing the function from being const. This allows 4138 // IRgen to use LLVM intrinsics for such functions. 4139 if (!getLangOptions().MathErrno && 4140 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4141 if (!FD->getAttr<ConstAttr>()) 4142 FD->addAttr(::new (Context) ConstAttr()); 4143 } 4144 4145 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4146 FD->addAttr(::new (Context) NoReturnAttr()); 4147 } 4148 4149 IdentifierInfo *Name = FD->getIdentifier(); 4150 if (!Name) 4151 return; 4152 if ((!getLangOptions().CPlusPlus && 4153 FD->getDeclContext()->isTranslationUnit()) || 4154 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4155 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4156 LinkageSpecDecl::lang_c)) { 4157 // Okay: this could be a libc/libm/Objective-C function we know 4158 // about. 4159 } else 4160 return; 4161 4162 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4163 // FIXME: NSLog and NSLogv should be target specific 4164 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4165 // FIXME: We known better than our headers. 4166 const_cast<FormatAttr *>(Format)->setType("printf"); 4167 } else 4168 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4169 Name->isStr("NSLogv") ? 0 : 2)); 4170 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4171 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4172 // target-specific builtins, perhaps? 4173 if (!FD->getAttr<FormatAttr>()) 4174 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4175 Name->isStr("vasprintf") ? 0 : 3)); 4176 } 4177} 4178 4179TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4180 DeclaratorInfo *DInfo) { 4181 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4182 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4183 4184 if (!DInfo) { 4185 assert(D.isInvalidType() && "no declarator info for valid type"); 4186 DInfo = Context.getTrivialDeclaratorInfo(T); 4187 } 4188 4189 // Scope manipulation handled by caller. 4190 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4191 D.getIdentifierLoc(), 4192 D.getIdentifier(), 4193 DInfo); 4194 4195 if (const TagType *TT = T->getAs<TagType>()) { 4196 TagDecl *TD = TT->getDecl(); 4197 4198 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4199 // keep track of the TypedefDecl. 4200 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4201 TD->setTypedefForAnonDecl(NewTD); 4202 } 4203 4204 if (D.isInvalidType()) 4205 NewTD->setInvalidDecl(); 4206 return NewTD; 4207} 4208 4209 4210/// \brief Determine whether a tag with a given kind is acceptable 4211/// as a redeclaration of the given tag declaration. 4212/// 4213/// \returns true if the new tag kind is acceptable, false otherwise. 4214bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4215 TagDecl::TagKind NewTag, 4216 SourceLocation NewTagLoc, 4217 const IdentifierInfo &Name) { 4218 // C++ [dcl.type.elab]p3: 4219 // The class-key or enum keyword present in the 4220 // elaborated-type-specifier shall agree in kind with the 4221 // declaration to which the name in theelaborated-type-specifier 4222 // refers. This rule also applies to the form of 4223 // elaborated-type-specifier that declares a class-name or 4224 // friend class since it can be construed as referring to the 4225 // definition of the class. Thus, in any 4226 // elaborated-type-specifier, the enum keyword shall be used to 4227 // refer to an enumeration (7.2), the union class-keyshall be 4228 // used to refer to a union (clause 9), and either the class or 4229 // struct class-key shall be used to refer to a class (clause 9) 4230 // declared using the class or struct class-key. 4231 TagDecl::TagKind OldTag = Previous->getTagKind(); 4232 if (OldTag == NewTag) 4233 return true; 4234 4235 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4236 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4237 // Warn about the struct/class tag mismatch. 4238 bool isTemplate = false; 4239 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4240 isTemplate = Record->getDescribedClassTemplate(); 4241 4242 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4243 << (NewTag == TagDecl::TK_class) 4244 << isTemplate << &Name 4245 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4246 OldTag == TagDecl::TK_class? "class" : "struct"); 4247 Diag(Previous->getLocation(), diag::note_previous_use); 4248 return true; 4249 } 4250 return false; 4251} 4252 4253/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4254/// former case, Name will be non-null. In the later case, Name will be null. 4255/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4256/// reference/declaration/definition of a tag. 4257Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4258 SourceLocation KWLoc, const CXXScopeSpec &SS, 4259 IdentifierInfo *Name, SourceLocation NameLoc, 4260 AttributeList *Attr, AccessSpecifier AS, 4261 MultiTemplateParamsArg TemplateParameterLists, 4262 bool &OwnedDecl, bool &IsDependent) { 4263 // If this is not a definition, it must have a name. 4264 assert((Name != 0 || TUK == TUK_Definition) && 4265 "Nameless record must be a definition!"); 4266 4267 OwnedDecl = false; 4268 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4269 4270 // FIXME: Check explicit specializations more carefully. 4271 bool isExplicitSpecialization = false; 4272 if (TUK != TUK_Reference) { 4273 if (TemplateParameterList *TemplateParams 4274 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4275 (TemplateParameterList**)TemplateParameterLists.get(), 4276 TemplateParameterLists.size(), 4277 isExplicitSpecialization)) { 4278 if (TemplateParams->size() > 0) { 4279 // This is a declaration or definition of a class template (which may 4280 // be a member of another template). 4281 OwnedDecl = false; 4282 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4283 SS, Name, NameLoc, Attr, 4284 TemplateParams, 4285 AS); 4286 TemplateParameterLists.release(); 4287 return Result.get(); 4288 } else { 4289 // The "template<>" header is extraneous. 4290 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4291 << ElaboratedType::getNameForTagKind(Kind) << Name; 4292 isExplicitSpecialization = true; 4293 } 4294 } 4295 4296 TemplateParameterLists.release(); 4297 } 4298 4299 DeclContext *SearchDC = CurContext; 4300 DeclContext *DC = CurContext; 4301 NamedDecl *PrevDecl = 0; 4302 bool isStdBadAlloc = false; 4303 bool Invalid = false; 4304 4305 bool RedeclarationOnly = (TUK != TUK_Reference); 4306 4307 if (Name && SS.isNotEmpty()) { 4308 // We have a nested-name tag ('struct foo::bar'). 4309 4310 // Check for invalid 'foo::'. 4311 if (SS.isInvalid()) { 4312 Name = 0; 4313 goto CreateNewDecl; 4314 } 4315 4316 // If this is a friend or a reference to a class in a dependent 4317 // context, don't try to make a decl for it. 4318 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4319 DC = computeDeclContext(SS, false); 4320 if (!DC) { 4321 IsDependent = true; 4322 return DeclPtrTy(); 4323 } 4324 } 4325 4326 if (RequireCompleteDeclContext(SS)) 4327 return DeclPtrTy::make((Decl *)0); 4328 4329 DC = computeDeclContext(SS, true); 4330 SearchDC = DC; 4331 // Look-up name inside 'foo::'. 4332 LookupResult R; 4333 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4334 4335 if (R.isAmbiguous()) { 4336 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4337 return DeclPtrTy(); 4338 } 4339 4340 if (R.getKind() == LookupResult::Found) 4341 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4342 4343 // A tag 'foo::bar' must already exist. 4344 if (!PrevDecl) { 4345 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4346 Name = 0; 4347 Invalid = true; 4348 goto CreateNewDecl; 4349 } 4350 } else if (Name) { 4351 // If this is a named struct, check to see if there was a previous forward 4352 // declaration or definition. 4353 // FIXME: We're looking into outer scopes here, even when we 4354 // shouldn't be. Doing so can result in ambiguities that we 4355 // shouldn't be diagnosing. 4356 LookupResult R; 4357 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4358 if (R.isAmbiguous()) { 4359 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4360 // FIXME: This is not best way to recover from case like: 4361 // 4362 // struct S s; 4363 // 4364 // causes needless "incomplete type" error later. 4365 Name = 0; 4366 PrevDecl = 0; 4367 Invalid = true; 4368 } else 4369 PrevDecl = R.getAsSingleDecl(Context); 4370 4371 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4372 // FIXME: This makes sure that we ignore the contexts associated 4373 // with C structs, unions, and enums when looking for a matching 4374 // tag declaration or definition. See the similar lookup tweak 4375 // in Sema::LookupName; is there a better way to deal with this? 4376 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4377 SearchDC = SearchDC->getParent(); 4378 } 4379 } 4380 4381 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4382 // Maybe we will complain about the shadowed template parameter. 4383 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4384 // Just pretend that we didn't see the previous declaration. 4385 PrevDecl = 0; 4386 } 4387 4388 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4389 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4390 // This is a declaration of or a reference to "std::bad_alloc". 4391 isStdBadAlloc = true; 4392 4393 if (!PrevDecl && StdBadAlloc) { 4394 // std::bad_alloc has been implicitly declared (but made invisible to 4395 // name lookup). Fill in this implicit declaration as the previous 4396 // declaration, so that the declarations get chained appropriately. 4397 PrevDecl = StdBadAlloc; 4398 } 4399 } 4400 4401 if (PrevDecl) { 4402 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4403 // If this is a use of a previous tag, or if the tag is already declared 4404 // in the same scope (so that the definition/declaration completes or 4405 // rementions the tag), reuse the decl. 4406 if (TUK == TUK_Reference || TUK == TUK_Friend || 4407 isDeclInScope(PrevDecl, SearchDC, S)) { 4408 // Make sure that this wasn't declared as an enum and now used as a 4409 // struct or something similar. 4410 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4411 bool SafeToContinue 4412 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4413 Kind != TagDecl::TK_enum); 4414 if (SafeToContinue) 4415 Diag(KWLoc, diag::err_use_with_wrong_tag) 4416 << Name 4417 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4418 PrevTagDecl->getKindName()); 4419 else 4420 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4421 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4422 4423 if (SafeToContinue) 4424 Kind = PrevTagDecl->getTagKind(); 4425 else { 4426 // Recover by making this an anonymous redefinition. 4427 Name = 0; 4428 PrevDecl = 0; 4429 Invalid = true; 4430 } 4431 } 4432 4433 if (!Invalid) { 4434 // If this is a use, just return the declaration we found. 4435 4436 // FIXME: In the future, return a variant or some other clue 4437 // for the consumer of this Decl to know it doesn't own it. 4438 // For our current ASTs this shouldn't be a problem, but will 4439 // need to be changed with DeclGroups. 4440 if (TUK == TUK_Reference || TUK == TUK_Friend) 4441 return DeclPtrTy::make(PrevDecl); 4442 4443 // Diagnose attempts to redefine a tag. 4444 if (TUK == TUK_Definition) { 4445 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4446 // If we're defining a specialization and the previous definition 4447 // is from an implicit instantiation, don't emit an error 4448 // here; we'll catch this in the general case below. 4449 if (!isExplicitSpecialization || 4450 !isa<CXXRecordDecl>(Def) || 4451 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4452 == TSK_ExplicitSpecialization) { 4453 Diag(NameLoc, diag::err_redefinition) << Name; 4454 Diag(Def->getLocation(), diag::note_previous_definition); 4455 // If this is a redefinition, recover by making this 4456 // struct be anonymous, which will make any later 4457 // references get the previous definition. 4458 Name = 0; 4459 PrevDecl = 0; 4460 Invalid = true; 4461 } 4462 } else { 4463 // If the type is currently being defined, complain 4464 // about a nested redefinition. 4465 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4466 if (Tag->isBeingDefined()) { 4467 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4468 Diag(PrevTagDecl->getLocation(), 4469 diag::note_previous_definition); 4470 Name = 0; 4471 PrevDecl = 0; 4472 Invalid = true; 4473 } 4474 } 4475 4476 // Okay, this is definition of a previously declared or referenced 4477 // tag PrevDecl. We're going to create a new Decl for it. 4478 } 4479 } 4480 // If we get here we have (another) forward declaration or we 4481 // have a definition. Just create a new decl. 4482 4483 } else { 4484 // If we get here, this is a definition of a new tag type in a nested 4485 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4486 // new decl/type. We set PrevDecl to NULL so that the entities 4487 // have distinct types. 4488 PrevDecl = 0; 4489 } 4490 // If we get here, we're going to create a new Decl. If PrevDecl 4491 // is non-NULL, it's a definition of the tag declared by 4492 // PrevDecl. If it's NULL, we have a new definition. 4493 } else { 4494 // PrevDecl is a namespace, template, or anything else 4495 // that lives in the IDNS_Tag identifier namespace. 4496 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4497 // The tag name clashes with a namespace name, issue an error and 4498 // recover by making this tag be anonymous. 4499 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4500 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4501 Name = 0; 4502 PrevDecl = 0; 4503 Invalid = true; 4504 } else { 4505 // The existing declaration isn't relevant to us; we're in a 4506 // new scope, so clear out the previous declaration. 4507 PrevDecl = 0; 4508 } 4509 } 4510 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4511 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4512 // C++ [basic.scope.pdecl]p5: 4513 // -- for an elaborated-type-specifier of the form 4514 // 4515 // class-key identifier 4516 // 4517 // if the elaborated-type-specifier is used in the 4518 // decl-specifier-seq or parameter-declaration-clause of a 4519 // function defined in namespace scope, the identifier is 4520 // declared as a class-name in the namespace that contains 4521 // the declaration; otherwise, except as a friend 4522 // declaration, the identifier is declared in the smallest 4523 // non-class, non-function-prototype scope that contains the 4524 // declaration. 4525 // 4526 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4527 // C structs and unions. 4528 // 4529 // GNU C also supports this behavior as part of its incomplete 4530 // enum types extension, while GNU C++ does not. 4531 // 4532 // Find the context where we'll be declaring the tag. 4533 // FIXME: We would like to maintain the current DeclContext as the 4534 // lexical context, 4535 while (SearchDC->isRecord()) 4536 SearchDC = SearchDC->getParent(); 4537 4538 // Find the scope where we'll be declaring the tag. 4539 while (S->isClassScope() || 4540 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4541 ((S->getFlags() & Scope::DeclScope) == 0) || 4542 (S->getEntity() && 4543 ((DeclContext *)S->getEntity())->isTransparentContext())) 4544 S = S->getParent(); 4545 4546 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4547 // C++ [namespace.memdef]p3: 4548 // If a friend declaration in a non-local class first declares a 4549 // class or function, the friend class or function is a member of 4550 // the innermost enclosing namespace. 4551 while (!SearchDC->isFileContext()) 4552 SearchDC = SearchDC->getParent(); 4553 4554 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4555 while (S->getEntity() != SearchDC) 4556 S = S->getParent(); 4557 } 4558 4559CreateNewDecl: 4560 4561 // If there is an identifier, use the location of the identifier as the 4562 // location of the decl, otherwise use the location of the struct/union 4563 // keyword. 4564 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4565 4566 // Otherwise, create a new declaration. If there is a previous 4567 // declaration of the same entity, the two will be linked via 4568 // PrevDecl. 4569 TagDecl *New; 4570 4571 if (Kind == TagDecl::TK_enum) { 4572 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4573 // enum X { A, B, C } D; D should chain to X. 4574 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4575 cast_or_null<EnumDecl>(PrevDecl)); 4576 // If this is an undefined enum, warn. 4577 if (TUK != TUK_Definition && !Invalid) { 4578 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4579 : diag::ext_forward_ref_enum; 4580 Diag(Loc, DK); 4581 } 4582 } else { 4583 // struct/union/class 4584 4585 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4586 // struct X { int A; } D; D should chain to X. 4587 if (getLangOptions().CPlusPlus) { 4588 // FIXME: Look for a way to use RecordDecl for simple structs. 4589 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4590 cast_or_null<CXXRecordDecl>(PrevDecl)); 4591 4592 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4593 StdBadAlloc = cast<CXXRecordDecl>(New); 4594 } else 4595 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4596 cast_or_null<RecordDecl>(PrevDecl)); 4597 } 4598 4599 if (Kind != TagDecl::TK_enum) { 4600 // Handle #pragma pack: if the #pragma pack stack has non-default 4601 // alignment, make up a packed attribute for this decl. These 4602 // attributes are checked when the ASTContext lays out the 4603 // structure. 4604 // 4605 // It is important for implementing the correct semantics that this 4606 // happen here (in act on tag decl). The #pragma pack stack is 4607 // maintained as a result of parser callbacks which can occur at 4608 // many points during the parsing of a struct declaration (because 4609 // the #pragma tokens are effectively skipped over during the 4610 // parsing of the struct). 4611 if (unsigned Alignment = getPragmaPackAlignment()) 4612 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4613 } 4614 4615 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4616 // C++ [dcl.typedef]p3: 4617 // [...] Similarly, in a given scope, a class or enumeration 4618 // shall not be declared with the same name as a typedef-name 4619 // that is declared in that scope and refers to a type other 4620 // than the class or enumeration itself. 4621 LookupResult Lookup; 4622 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4623 TypedefDecl *PrevTypedef = 0; 4624 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4625 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4626 4627 NamedDecl *PrevTypedefNamed = PrevTypedef; 4628 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4629 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4630 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4631 Diag(Loc, diag::err_tag_definition_of_typedef) 4632 << Context.getTypeDeclType(New) 4633 << PrevTypedef->getUnderlyingType(); 4634 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4635 Invalid = true; 4636 } 4637 } 4638 4639 // If this is a specialization of a member class (of a class template), 4640 // check the specialization. 4641 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4642 Invalid = true; 4643 4644 if (Invalid) 4645 New->setInvalidDecl(); 4646 4647 if (Attr) 4648 ProcessDeclAttributeList(S, New, Attr); 4649 4650 // If we're declaring or defining a tag in function prototype scope 4651 // in C, note that this type can only be used within the function. 4652 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4653 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4654 4655 // Set the lexical context. If the tag has a C++ scope specifier, the 4656 // lexical context will be different from the semantic context. 4657 New->setLexicalDeclContext(CurContext); 4658 4659 // Mark this as a friend decl if applicable. 4660 if (TUK == TUK_Friend) 4661 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4662 4663 // Set the access specifier. 4664 if (!Invalid && TUK != TUK_Friend) 4665 SetMemberAccessSpecifier(New, PrevDecl, AS); 4666 4667 if (TUK == TUK_Definition) 4668 New->startDefinition(); 4669 4670 // If this has an identifier, add it to the scope stack. 4671 if (TUK == TUK_Friend) { 4672 // We might be replacing an existing declaration in the lookup tables; 4673 // if so, borrow its access specifier. 4674 if (PrevDecl) 4675 New->setAccess(PrevDecl->getAccess()); 4676 4677 // Friend tag decls are visible in fairly strange ways. 4678 if (!CurContext->isDependentContext()) { 4679 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4680 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4681 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4682 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4683 } 4684 } else if (Name) { 4685 S = getNonFieldDeclScope(S); 4686 PushOnScopeChains(New, S); 4687 } else { 4688 CurContext->addDecl(New); 4689 } 4690 4691 // If this is the C FILE type, notify the AST context. 4692 if (IdentifierInfo *II = New->getIdentifier()) 4693 if (!New->isInvalidDecl() && 4694 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4695 II->isStr("FILE")) 4696 Context.setFILEDecl(New); 4697 4698 OwnedDecl = true; 4699 return DeclPtrTy::make(New); 4700} 4701 4702void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4703 AdjustDeclIfTemplate(TagD); 4704 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4705 4706 // Enter the tag context. 4707 PushDeclContext(S, Tag); 4708 4709 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4710 FieldCollector->StartClass(); 4711 4712 if (Record->getIdentifier()) { 4713 // C++ [class]p2: 4714 // [...] The class-name is also inserted into the scope of the 4715 // class itself; this is known as the injected-class-name. For 4716 // purposes of access checking, the injected-class-name is treated 4717 // as if it were a public member name. 4718 CXXRecordDecl *InjectedClassName 4719 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4720 CurContext, Record->getLocation(), 4721 Record->getIdentifier(), 4722 Record->getTagKeywordLoc(), 4723 Record); 4724 InjectedClassName->setImplicit(); 4725 InjectedClassName->setAccess(AS_public); 4726 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4727 InjectedClassName->setDescribedClassTemplate(Template); 4728 PushOnScopeChains(InjectedClassName, S); 4729 assert(InjectedClassName->isInjectedClassName() && 4730 "Broken injected-class-name"); 4731 } 4732 } 4733} 4734 4735void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4736 SourceLocation RBraceLoc) { 4737 AdjustDeclIfTemplate(TagD); 4738 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4739 Tag->setRBraceLoc(RBraceLoc); 4740 4741 if (isa<CXXRecordDecl>(Tag)) 4742 FieldCollector->FinishClass(); 4743 4744 // Exit this scope of this tag's definition. 4745 PopDeclContext(); 4746 4747 // Notify the consumer that we've defined a tag. 4748 Consumer.HandleTagDeclDefinition(Tag); 4749} 4750 4751// Note that FieldName may be null for anonymous bitfields. 4752bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4753 QualType FieldTy, const Expr *BitWidth, 4754 bool *ZeroWidth) { 4755 // Default to true; that shouldn't confuse checks for emptiness 4756 if (ZeroWidth) 4757 *ZeroWidth = true; 4758 4759 // C99 6.7.2.1p4 - verify the field type. 4760 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4761 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4762 // Handle incomplete types with specific error. 4763 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4764 return true; 4765 if (FieldName) 4766 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4767 << FieldName << FieldTy << BitWidth->getSourceRange(); 4768 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4769 << FieldTy << BitWidth->getSourceRange(); 4770 } 4771 4772 // If the bit-width is type- or value-dependent, don't try to check 4773 // it now. 4774 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4775 return false; 4776 4777 llvm::APSInt Value; 4778 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4779 return true; 4780 4781 if (Value != 0 && ZeroWidth) 4782 *ZeroWidth = false; 4783 4784 // Zero-width bitfield is ok for anonymous field. 4785 if (Value == 0 && FieldName) 4786 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4787 4788 if (Value.isSigned() && Value.isNegative()) { 4789 if (FieldName) 4790 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4791 << FieldName << Value.toString(10); 4792 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4793 << Value.toString(10); 4794 } 4795 4796 if (!FieldTy->isDependentType()) { 4797 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4798 if (Value.getZExtValue() > TypeSize) { 4799 if (FieldName) 4800 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4801 << FieldName << (unsigned)TypeSize; 4802 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4803 << (unsigned)TypeSize; 4804 } 4805 } 4806 4807 return false; 4808} 4809 4810/// ActOnField - Each field of a struct/union/class is passed into this in order 4811/// to create a FieldDecl object for it. 4812Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4813 SourceLocation DeclStart, 4814 Declarator &D, ExprTy *BitfieldWidth) { 4815 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4816 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4817 AS_public); 4818 return DeclPtrTy::make(Res); 4819} 4820 4821/// HandleField - Analyze a field of a C struct or a C++ data member. 4822/// 4823FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4824 SourceLocation DeclStart, 4825 Declarator &D, Expr *BitWidth, 4826 AccessSpecifier AS) { 4827 IdentifierInfo *II = D.getIdentifier(); 4828 SourceLocation Loc = DeclStart; 4829 if (II) Loc = D.getIdentifierLoc(); 4830 4831 DeclaratorInfo *DInfo = 0; 4832 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4833 if (getLangOptions().CPlusPlus) 4834 CheckExtraCXXDefaultArguments(D); 4835 4836 DiagnoseFunctionSpecifiers(D); 4837 4838 if (D.getDeclSpec().isThreadSpecified()) 4839 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4840 4841 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4842 4843 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4844 // Maybe we will complain about the shadowed template parameter. 4845 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4846 // Just pretend that we didn't see the previous declaration. 4847 PrevDecl = 0; 4848 } 4849 4850 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4851 PrevDecl = 0; 4852 4853 bool Mutable 4854 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4855 SourceLocation TSSL = D.getSourceRange().getBegin(); 4856 FieldDecl *NewFD 4857 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4858 AS, PrevDecl, &D); 4859 if (NewFD->isInvalidDecl() && PrevDecl) { 4860 // Don't introduce NewFD into scope; there's already something 4861 // with the same name in the same scope. 4862 } else if (II) { 4863 PushOnScopeChains(NewFD, S); 4864 } else 4865 Record->addDecl(NewFD); 4866 4867 return NewFD; 4868} 4869 4870/// \brief Build a new FieldDecl and check its well-formedness. 4871/// 4872/// This routine builds a new FieldDecl given the fields name, type, 4873/// record, etc. \p PrevDecl should refer to any previous declaration 4874/// with the same name and in the same scope as the field to be 4875/// created. 4876/// 4877/// \returns a new FieldDecl. 4878/// 4879/// \todo The Declarator argument is a hack. It will be removed once 4880FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4881 DeclaratorInfo *DInfo, 4882 RecordDecl *Record, SourceLocation Loc, 4883 bool Mutable, Expr *BitWidth, 4884 SourceLocation TSSL, 4885 AccessSpecifier AS, NamedDecl *PrevDecl, 4886 Declarator *D) { 4887 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4888 bool InvalidDecl = false; 4889 if (D) InvalidDecl = D->isInvalidType(); 4890 4891 // If we receive a broken type, recover by assuming 'int' and 4892 // marking this declaration as invalid. 4893 if (T.isNull()) { 4894 InvalidDecl = true; 4895 T = Context.IntTy; 4896 } 4897 4898 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4899 // than a variably modified type. 4900 if (T->isVariablyModifiedType()) { 4901 bool SizeIsNegative; 4902 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4903 SizeIsNegative); 4904 if (!FixedTy.isNull()) { 4905 Diag(Loc, diag::warn_illegal_constant_array_size); 4906 T = FixedTy; 4907 } else { 4908 if (SizeIsNegative) 4909 Diag(Loc, diag::err_typecheck_negative_array_size); 4910 else 4911 Diag(Loc, diag::err_typecheck_field_variable_size); 4912 InvalidDecl = true; 4913 } 4914 } 4915 4916 // Fields can not have abstract class types 4917 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4918 AbstractFieldType)) 4919 InvalidDecl = true; 4920 4921 bool ZeroWidth = false; 4922 // If this is declared as a bit-field, check the bit-field. 4923 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4924 InvalidDecl = true; 4925 DeleteExpr(BitWidth); 4926 BitWidth = 0; 4927 ZeroWidth = false; 4928 } 4929 4930 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4931 BitWidth, Mutable); 4932 if (InvalidDecl) 4933 NewFD->setInvalidDecl(); 4934 4935 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4936 Diag(Loc, diag::err_duplicate_member) << II; 4937 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4938 NewFD->setInvalidDecl(); 4939 } 4940 4941 if (getLangOptions().CPlusPlus) { 4942 QualType EltTy = Context.getBaseElementType(T); 4943 4944 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4945 4946 if (!T->isPODType()) 4947 CXXRecord->setPOD(false); 4948 if (!ZeroWidth) 4949 CXXRecord->setEmpty(false); 4950 4951 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4952 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4953 4954 if (!RDecl->hasTrivialConstructor()) 4955 CXXRecord->setHasTrivialConstructor(false); 4956 if (!RDecl->hasTrivialCopyConstructor()) 4957 CXXRecord->setHasTrivialCopyConstructor(false); 4958 if (!RDecl->hasTrivialCopyAssignment()) 4959 CXXRecord->setHasTrivialCopyAssignment(false); 4960 if (!RDecl->hasTrivialDestructor()) 4961 CXXRecord->setHasTrivialDestructor(false); 4962 4963 // C++ 9.5p1: An object of a class with a non-trivial 4964 // constructor, a non-trivial copy constructor, a non-trivial 4965 // destructor, or a non-trivial copy assignment operator 4966 // cannot be a member of a union, nor can an array of such 4967 // objects. 4968 // TODO: C++0x alters this restriction significantly. 4969 if (Record->isUnion()) { 4970 // We check for copy constructors before constructors 4971 // because otherwise we'll never get complaints about 4972 // copy constructors. 4973 4974 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4975 4976 CXXSpecialMember member; 4977 if (!RDecl->hasTrivialCopyConstructor()) 4978 member = CXXCopyConstructor; 4979 else if (!RDecl->hasTrivialConstructor()) 4980 member = CXXDefaultConstructor; 4981 else if (!RDecl->hasTrivialCopyAssignment()) 4982 member = CXXCopyAssignment; 4983 else if (!RDecl->hasTrivialDestructor()) 4984 member = CXXDestructor; 4985 else 4986 member = invalid; 4987 4988 if (member != invalid) { 4989 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4990 DiagnoseNontrivial(RT, member); 4991 NewFD->setInvalidDecl(); 4992 } 4993 } 4994 } 4995 } 4996 4997 // FIXME: We need to pass in the attributes given an AST 4998 // representation, not a parser representation. 4999 if (D) 5000 // FIXME: What to pass instead of TUScope? 5001 ProcessDeclAttributes(TUScope, NewFD, *D); 5002 5003 if (T.isObjCGCWeak()) 5004 Diag(Loc, diag::warn_attribute_weak_on_field); 5005 5006 NewFD->setAccess(AS); 5007 5008 // C++ [dcl.init.aggr]p1: 5009 // An aggregate is an array or a class (clause 9) with [...] no 5010 // private or protected non-static data members (clause 11). 5011 // A POD must be an aggregate. 5012 if (getLangOptions().CPlusPlus && 5013 (AS == AS_private || AS == AS_protected)) { 5014 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5015 CXXRecord->setAggregate(false); 5016 CXXRecord->setPOD(false); 5017 } 5018 5019 return NewFD; 5020} 5021 5022/// DiagnoseNontrivial - Given that a class has a non-trivial 5023/// special member, figure out why. 5024void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5025 QualType QT(T, 0U); 5026 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5027 5028 // Check whether the member was user-declared. 5029 switch (member) { 5030 case CXXDefaultConstructor: 5031 if (RD->hasUserDeclaredConstructor()) { 5032 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5033 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5034 const FunctionDecl *body = 0; 5035 ci->getBody(body); 5036 if (!body || 5037 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5038 SourceLocation CtorLoc = ci->getLocation(); 5039 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5040 return; 5041 } 5042 } 5043 5044 assert(0 && "found no user-declared constructors"); 5045 return; 5046 } 5047 break; 5048 5049 case CXXCopyConstructor: 5050 if (RD->hasUserDeclaredCopyConstructor()) { 5051 SourceLocation CtorLoc = 5052 RD->getCopyConstructor(Context, 0)->getLocation(); 5053 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5054 return; 5055 } 5056 break; 5057 5058 case CXXCopyAssignment: 5059 if (RD->hasUserDeclaredCopyAssignment()) { 5060 // FIXME: this should use the location of the copy 5061 // assignment, not the type. 5062 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5063 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5064 return; 5065 } 5066 break; 5067 5068 case CXXDestructor: 5069 if (RD->hasUserDeclaredDestructor()) { 5070 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5071 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5072 return; 5073 } 5074 break; 5075 } 5076 5077 typedef CXXRecordDecl::base_class_iterator base_iter; 5078 5079 // Virtual bases and members inhibit trivial copying/construction, 5080 // but not trivial destruction. 5081 if (member != CXXDestructor) { 5082 // Check for virtual bases. vbases includes indirect virtual bases, 5083 // so we just iterate through the direct bases. 5084 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5085 if (bi->isVirtual()) { 5086 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5087 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5088 return; 5089 } 5090 5091 // Check for virtual methods. 5092 typedef CXXRecordDecl::method_iterator meth_iter; 5093 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5094 ++mi) { 5095 if (mi->isVirtual()) { 5096 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5097 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5098 return; 5099 } 5100 } 5101 } 5102 5103 bool (CXXRecordDecl::*hasTrivial)() const; 5104 switch (member) { 5105 case CXXDefaultConstructor: 5106 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5107 case CXXCopyConstructor: 5108 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5109 case CXXCopyAssignment: 5110 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5111 case CXXDestructor: 5112 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5113 default: 5114 assert(0 && "unexpected special member"); return; 5115 } 5116 5117 // Check for nontrivial bases (and recurse). 5118 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5119 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5120 assert(BaseRT && "Don't know how to handle dependent bases"); 5121 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5122 if (!(BaseRecTy->*hasTrivial)()) { 5123 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5124 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5125 DiagnoseNontrivial(BaseRT, member); 5126 return; 5127 } 5128 } 5129 5130 // Check for nontrivial members (and recurse). 5131 typedef RecordDecl::field_iterator field_iter; 5132 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5133 ++fi) { 5134 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5135 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5136 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5137 5138 if (!(EltRD->*hasTrivial)()) { 5139 SourceLocation FLoc = (*fi)->getLocation(); 5140 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5141 DiagnoseNontrivial(EltRT, member); 5142 return; 5143 } 5144 } 5145 } 5146 5147 assert(0 && "found no explanation for non-trivial member"); 5148} 5149 5150/// TranslateIvarVisibility - Translate visibility from a token ID to an 5151/// AST enum value. 5152static ObjCIvarDecl::AccessControl 5153TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5154 switch (ivarVisibility) { 5155 default: assert(0 && "Unknown visitibility kind"); 5156 case tok::objc_private: return ObjCIvarDecl::Private; 5157 case tok::objc_public: return ObjCIvarDecl::Public; 5158 case tok::objc_protected: return ObjCIvarDecl::Protected; 5159 case tok::objc_package: return ObjCIvarDecl::Package; 5160 } 5161} 5162 5163/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5164/// in order to create an IvarDecl object for it. 5165Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5166 SourceLocation DeclStart, 5167 DeclPtrTy IntfDecl, 5168 Declarator &D, ExprTy *BitfieldWidth, 5169 tok::ObjCKeywordKind Visibility) { 5170 5171 IdentifierInfo *II = D.getIdentifier(); 5172 Expr *BitWidth = (Expr*)BitfieldWidth; 5173 SourceLocation Loc = DeclStart; 5174 if (II) Loc = D.getIdentifierLoc(); 5175 5176 // FIXME: Unnamed fields can be handled in various different ways, for 5177 // example, unnamed unions inject all members into the struct namespace! 5178 5179 DeclaratorInfo *DInfo = 0; 5180 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5181 5182 if (BitWidth) { 5183 // 6.7.2.1p3, 6.7.2.1p4 5184 if (VerifyBitField(Loc, II, T, BitWidth)) { 5185 D.setInvalidType(); 5186 DeleteExpr(BitWidth); 5187 BitWidth = 0; 5188 } 5189 } else { 5190 // Not a bitfield. 5191 5192 // validate II. 5193 5194 } 5195 5196 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5197 // than a variably modified type. 5198 if (T->isVariablyModifiedType()) { 5199 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5200 D.setInvalidType(); 5201 } 5202 5203 // Get the visibility (access control) for this ivar. 5204 ObjCIvarDecl::AccessControl ac = 5205 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5206 : ObjCIvarDecl::None; 5207 // Must set ivar's DeclContext to its enclosing interface. 5208 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5209 DeclContext *EnclosingContext; 5210 if (ObjCImplementationDecl *IMPDecl = 5211 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5212 // Case of ivar declared in an implementation. Context is that of its class. 5213 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5214 assert(IDecl && "No class- ActOnIvar"); 5215 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5216 } else 5217 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5218 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5219 5220 // Construct the decl. 5221 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5222 EnclosingContext, Loc, II, T, 5223 DInfo, ac, (Expr *)BitfieldWidth); 5224 5225 if (II) { 5226 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5227 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5228 && !isa<TagDecl>(PrevDecl)) { 5229 Diag(Loc, diag::err_duplicate_member) << II; 5230 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5231 NewID->setInvalidDecl(); 5232 } 5233 } 5234 5235 // Process attributes attached to the ivar. 5236 ProcessDeclAttributes(S, NewID, D); 5237 5238 if (D.isInvalidType()) 5239 NewID->setInvalidDecl(); 5240 5241 if (II) { 5242 // FIXME: When interfaces are DeclContexts, we'll need to add 5243 // these to the interface. 5244 S->AddDecl(DeclPtrTy::make(NewID)); 5245 IdResolver.AddDecl(NewID); 5246 } 5247 5248 return DeclPtrTy::make(NewID); 5249} 5250 5251void Sema::ActOnFields(Scope* S, 5252 SourceLocation RecLoc, DeclPtrTy RecDecl, 5253 DeclPtrTy *Fields, unsigned NumFields, 5254 SourceLocation LBrac, SourceLocation RBrac, 5255 AttributeList *Attr) { 5256 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5257 assert(EnclosingDecl && "missing record or interface decl"); 5258 5259 // If the decl this is being inserted into is invalid, then it may be a 5260 // redeclaration or some other bogus case. Don't try to add fields to it. 5261 if (EnclosingDecl->isInvalidDecl()) { 5262 // FIXME: Deallocate fields? 5263 return; 5264 } 5265 5266 5267 // Verify that all the fields are okay. 5268 unsigned NumNamedMembers = 0; 5269 llvm::SmallVector<FieldDecl*, 32> RecFields; 5270 5271 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5272 for (unsigned i = 0; i != NumFields; ++i) { 5273 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5274 5275 // Get the type for the field. 5276 Type *FDTy = FD->getType().getTypePtr(); 5277 5278 if (!FD->isAnonymousStructOrUnion()) { 5279 // Remember all fields written by the user. 5280 RecFields.push_back(FD); 5281 } 5282 5283 // If the field is already invalid for some reason, don't emit more 5284 // diagnostics about it. 5285 if (FD->isInvalidDecl()) 5286 continue; 5287 5288 // C99 6.7.2.1p2: 5289 // A structure or union shall not contain a member with 5290 // incomplete or function type (hence, a structure shall not 5291 // contain an instance of itself, but may contain a pointer to 5292 // an instance of itself), except that the last member of a 5293 // structure with more than one named member may have incomplete 5294 // array type; such a structure (and any union containing, 5295 // possibly recursively, a member that is such a structure) 5296 // shall not be a member of a structure or an element of an 5297 // array. 5298 if (FDTy->isFunctionType()) { 5299 // Field declared as a function. 5300 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5301 << FD->getDeclName(); 5302 FD->setInvalidDecl(); 5303 EnclosingDecl->setInvalidDecl(); 5304 continue; 5305 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5306 Record && Record->isStruct()) { 5307 // Flexible array member. 5308 if (NumNamedMembers < 1) { 5309 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5310 << FD->getDeclName(); 5311 FD->setInvalidDecl(); 5312 EnclosingDecl->setInvalidDecl(); 5313 continue; 5314 } 5315 // Okay, we have a legal flexible array member at the end of the struct. 5316 if (Record) 5317 Record->setHasFlexibleArrayMember(true); 5318 } else if (!FDTy->isDependentType() && 5319 RequireCompleteType(FD->getLocation(), FD->getType(), 5320 diag::err_field_incomplete)) { 5321 // Incomplete type 5322 FD->setInvalidDecl(); 5323 EnclosingDecl->setInvalidDecl(); 5324 continue; 5325 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5326 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5327 // If this is a member of a union, then entire union becomes "flexible". 5328 if (Record && Record->isUnion()) { 5329 Record->setHasFlexibleArrayMember(true); 5330 } else { 5331 // If this is a struct/class and this is not the last element, reject 5332 // it. Note that GCC supports variable sized arrays in the middle of 5333 // structures. 5334 if (i != NumFields-1) 5335 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5336 << FD->getDeclName() << FD->getType(); 5337 else { 5338 // We support flexible arrays at the end of structs in 5339 // other structs as an extension. 5340 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5341 << FD->getDeclName(); 5342 if (Record) 5343 Record->setHasFlexibleArrayMember(true); 5344 } 5345 } 5346 } 5347 if (Record && FDTTy->getDecl()->hasObjectMember()) 5348 Record->setHasObjectMember(true); 5349 } else if (FDTy->isObjCInterfaceType()) { 5350 /// A field cannot be an Objective-c object 5351 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5352 FD->setInvalidDecl(); 5353 EnclosingDecl->setInvalidDecl(); 5354 continue; 5355 } else if (getLangOptions().ObjC1 && 5356 getLangOptions().getGCMode() != LangOptions::NonGC && 5357 Record && 5358 (FD->getType()->isObjCObjectPointerType() || 5359 FD->getType().isObjCGCStrong())) 5360 Record->setHasObjectMember(true); 5361 // Keep track of the number of named members. 5362 if (FD->getIdentifier()) 5363 ++NumNamedMembers; 5364 } 5365 5366 // Okay, we successfully defined 'Record'. 5367 if (Record) { 5368 Record->completeDefinition(Context); 5369 } else { 5370 ObjCIvarDecl **ClsFields = 5371 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5372 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5373 ID->setIVarList(ClsFields, RecFields.size(), Context); 5374 ID->setLocEnd(RBrac); 5375 // Add ivar's to class's DeclContext. 5376 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5377 ClsFields[i]->setLexicalDeclContext(ID); 5378 ID->addDecl(ClsFields[i]); 5379 } 5380 // Must enforce the rule that ivars in the base classes may not be 5381 // duplicates. 5382 if (ID->getSuperClass()) { 5383 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5384 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5385 ObjCIvarDecl* Ivar = (*IVI); 5386 5387 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5388 ObjCIvarDecl* prevIvar = 5389 ID->getSuperClass()->lookupInstanceVariable(II); 5390 if (prevIvar) { 5391 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5392 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5393 } 5394 } 5395 } 5396 } 5397 } else if (ObjCImplementationDecl *IMPDecl = 5398 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5399 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5400 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5401 // Ivar declared in @implementation never belongs to the implementation. 5402 // Only it is in implementation's lexical context. 5403 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5404 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5405 } 5406 } 5407 5408 if (Attr) 5409 ProcessDeclAttributeList(S, Record, Attr); 5410} 5411 5412EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5413 EnumConstantDecl *LastEnumConst, 5414 SourceLocation IdLoc, 5415 IdentifierInfo *Id, 5416 ExprArg val) { 5417 Expr *Val = (Expr *)val.get(); 5418 5419 llvm::APSInt EnumVal(32); 5420 QualType EltTy; 5421 if (Val) { 5422 if (Val->isTypeDependent()) 5423 EltTy = Context.DependentTy; 5424 else { 5425 // Make sure to promote the operand type to int. 5426 UsualUnaryConversions(Val); 5427 if (Val != val.get()) { 5428 val.release(); 5429 val = Val; 5430 } 5431 5432 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5433 SourceLocation ExpLoc; 5434 if (!Val->isValueDependent() && 5435 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5436 Val = 0; 5437 } else { 5438 EltTy = Val->getType(); 5439 } 5440 } 5441 } 5442 5443 if (!Val) { 5444 if (LastEnumConst) { 5445 // Assign the last value + 1. 5446 EnumVal = LastEnumConst->getInitVal(); 5447 ++EnumVal; 5448 5449 // Check for overflow on increment. 5450 if (EnumVal < LastEnumConst->getInitVal()) 5451 Diag(IdLoc, diag::warn_enum_value_overflow); 5452 5453 EltTy = LastEnumConst->getType(); 5454 } else { 5455 // First value, set to zero. 5456 EltTy = Context.IntTy; 5457 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5458 } 5459 } 5460 5461 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5462 5463 val.release(); 5464 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5465 Val, EnumVal); 5466} 5467 5468 5469Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5470 DeclPtrTy lastEnumConst, 5471 SourceLocation IdLoc, 5472 IdentifierInfo *Id, 5473 SourceLocation EqualLoc, ExprTy *val) { 5474 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5475 EnumConstantDecl *LastEnumConst = 5476 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5477 Expr *Val = static_cast<Expr*>(val); 5478 5479 // The scope passed in may not be a decl scope. Zip up the scope tree until 5480 // we find one that is. 5481 S = getNonFieldDeclScope(S); 5482 5483 // Verify that there isn't already something declared with this name in this 5484 // scope. 5485 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5486 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5487 // Maybe we will complain about the shadowed template parameter. 5488 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5489 // Just pretend that we didn't see the previous declaration. 5490 PrevDecl = 0; 5491 } 5492 5493 if (PrevDecl) { 5494 // When in C++, we may get a TagDecl with the same name; in this case the 5495 // enum constant will 'hide' the tag. 5496 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5497 "Received TagDecl when not in C++!"); 5498 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5499 if (isa<EnumConstantDecl>(PrevDecl)) 5500 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5501 else 5502 Diag(IdLoc, diag::err_redefinition) << Id; 5503 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5504 if (Val) Val->Destroy(Context); 5505 return DeclPtrTy(); 5506 } 5507 } 5508 5509 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5510 IdLoc, Id, Owned(Val)); 5511 5512 // Register this decl in the current scope stack. 5513 if (New) 5514 PushOnScopeChains(New, S); 5515 5516 return DeclPtrTy::make(New); 5517} 5518 5519void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5520 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5521 DeclPtrTy *Elements, unsigned NumElements, 5522 Scope *S, AttributeList *Attr) { 5523 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5524 QualType EnumType = Context.getTypeDeclType(Enum); 5525 5526 if (Attr) 5527 ProcessDeclAttributeList(S, Enum, Attr); 5528 5529 // TODO: If the result value doesn't fit in an int, it must be a long or long 5530 // long value. ISO C does not support this, but GCC does as an extension, 5531 // emit a warning. 5532 unsigned IntWidth = Context.Target.getIntWidth(); 5533 unsigned CharWidth = Context.Target.getCharWidth(); 5534 unsigned ShortWidth = Context.Target.getShortWidth(); 5535 5536 // Verify that all the values are okay, compute the size of the values, and 5537 // reverse the list. 5538 unsigned NumNegativeBits = 0; 5539 unsigned NumPositiveBits = 0; 5540 5541 // Keep track of whether all elements have type int. 5542 bool AllElementsInt = true; 5543 5544 for (unsigned i = 0; i != NumElements; ++i) { 5545 EnumConstantDecl *ECD = 5546 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5547 if (!ECD) continue; // Already issued a diagnostic. 5548 5549 // If the enum value doesn't fit in an int, emit an extension warning. 5550 const llvm::APSInt &InitVal = ECD->getInitVal(); 5551 assert(InitVal.getBitWidth() >= IntWidth && 5552 "Should have promoted value to int"); 5553 if (InitVal.getBitWidth() > IntWidth) { 5554 llvm::APSInt V(InitVal); 5555 V.trunc(IntWidth); 5556 V.extend(InitVal.getBitWidth()); 5557 if (V != InitVal) 5558 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5559 << InitVal.toString(10); 5560 } 5561 5562 // Keep track of the size of positive and negative values. 5563 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5564 NumPositiveBits = std::max(NumPositiveBits, 5565 (unsigned)InitVal.getActiveBits()); 5566 else 5567 NumNegativeBits = std::max(NumNegativeBits, 5568 (unsigned)InitVal.getMinSignedBits()); 5569 5570 // Keep track of whether every enum element has type int (very commmon). 5571 if (AllElementsInt) 5572 AllElementsInt = ECD->getType() == Context.IntTy; 5573 } 5574 5575 // Figure out the type that should be used for this enum. 5576 // FIXME: Support -fshort-enums. 5577 QualType BestType; 5578 unsigned BestWidth; 5579 5580 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5581 5582 if (NumNegativeBits) { 5583 // If there is a negative value, figure out the smallest integer type (of 5584 // int/long/longlong) that fits. 5585 // If it's packed, check also if it fits a char or a short. 5586 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5587 BestType = Context.SignedCharTy; 5588 BestWidth = CharWidth; 5589 } else if (Packed && NumNegativeBits <= ShortWidth && 5590 NumPositiveBits < ShortWidth) { 5591 BestType = Context.ShortTy; 5592 BestWidth = ShortWidth; 5593 } 5594 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5595 BestType = Context.IntTy; 5596 BestWidth = IntWidth; 5597 } else { 5598 BestWidth = Context.Target.getLongWidth(); 5599 5600 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5601 BestType = Context.LongTy; 5602 else { 5603 BestWidth = Context.Target.getLongLongWidth(); 5604 5605 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5606 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5607 BestType = Context.LongLongTy; 5608 } 5609 } 5610 } else { 5611 // If there is no negative value, figure out which of uint, ulong, ulonglong 5612 // fits. 5613 // If it's packed, check also if it fits a char or a short. 5614 if (Packed && NumPositiveBits <= CharWidth) { 5615 BestType = Context.UnsignedCharTy; 5616 BestWidth = CharWidth; 5617 } else if (Packed && NumPositiveBits <= ShortWidth) { 5618 BestType = Context.UnsignedShortTy; 5619 BestWidth = ShortWidth; 5620 } 5621 else if (NumPositiveBits <= IntWidth) { 5622 BestType = Context.UnsignedIntTy; 5623 BestWidth = IntWidth; 5624 } else if (NumPositiveBits <= 5625 (BestWidth = Context.Target.getLongWidth())) { 5626 BestType = Context.UnsignedLongTy; 5627 } else { 5628 BestWidth = Context.Target.getLongLongWidth(); 5629 assert(NumPositiveBits <= BestWidth && 5630 "How could an initializer get larger than ULL?"); 5631 BestType = Context.UnsignedLongLongTy; 5632 } 5633 } 5634 5635 // Loop over all of the enumerator constants, changing their types to match 5636 // the type of the enum if needed. 5637 for (unsigned i = 0; i != NumElements; ++i) { 5638 EnumConstantDecl *ECD = 5639 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5640 if (!ECD) continue; // Already issued a diagnostic. 5641 5642 // Standard C says the enumerators have int type, but we allow, as an 5643 // extension, the enumerators to be larger than int size. If each 5644 // enumerator value fits in an int, type it as an int, otherwise type it the 5645 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5646 // that X has type 'int', not 'unsigned'. 5647 if (ECD->getType() == Context.IntTy) { 5648 // Make sure the init value is signed. 5649 llvm::APSInt IV = ECD->getInitVal(); 5650 IV.setIsSigned(true); 5651 ECD->setInitVal(IV); 5652 5653 if (getLangOptions().CPlusPlus) 5654 // C++ [dcl.enum]p4: Following the closing brace of an 5655 // enum-specifier, each enumerator has the type of its 5656 // enumeration. 5657 ECD->setType(EnumType); 5658 continue; // Already int type. 5659 } 5660 5661 // Determine whether the value fits into an int. 5662 llvm::APSInt InitVal = ECD->getInitVal(); 5663 bool FitsInInt; 5664 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5665 FitsInInt = InitVal.getActiveBits() < IntWidth; 5666 else 5667 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5668 5669 // If it fits into an integer type, force it. Otherwise force it to match 5670 // the enum decl type. 5671 QualType NewTy; 5672 unsigned NewWidth; 5673 bool NewSign; 5674 if (FitsInInt) { 5675 NewTy = Context.IntTy; 5676 NewWidth = IntWidth; 5677 NewSign = true; 5678 } else if (ECD->getType() == BestType) { 5679 // Already the right type! 5680 if (getLangOptions().CPlusPlus) 5681 // C++ [dcl.enum]p4: Following the closing brace of an 5682 // enum-specifier, each enumerator has the type of its 5683 // enumeration. 5684 ECD->setType(EnumType); 5685 continue; 5686 } else { 5687 NewTy = BestType; 5688 NewWidth = BestWidth; 5689 NewSign = BestType->isSignedIntegerType(); 5690 } 5691 5692 // Adjust the APSInt value. 5693 InitVal.extOrTrunc(NewWidth); 5694 InitVal.setIsSigned(NewSign); 5695 ECD->setInitVal(InitVal); 5696 5697 // Adjust the Expr initializer and type. 5698 if (ECD->getInitExpr()) 5699 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5700 CastExpr::CK_IntegralCast, 5701 ECD->getInitExpr(), 5702 /*isLvalue=*/false)); 5703 if (getLangOptions().CPlusPlus) 5704 // C++ [dcl.enum]p4: Following the closing brace of an 5705 // enum-specifier, each enumerator has the type of its 5706 // enumeration. 5707 ECD->setType(EnumType); 5708 else 5709 ECD->setType(NewTy); 5710 } 5711 5712 Enum->completeDefinition(Context, BestType); 5713} 5714 5715Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5716 ExprArg expr) { 5717 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5718 5719 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5720 Loc, AsmString); 5721 CurContext->addDecl(New); 5722 return DeclPtrTy::make(New); 5723} 5724 5725void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5726 SourceLocation PragmaLoc, 5727 SourceLocation NameLoc) { 5728 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5729 5730 if (PrevDecl) { 5731 PrevDecl->addAttr(::new (Context) WeakAttr()); 5732 } else { 5733 (void)WeakUndeclaredIdentifiers.insert( 5734 std::pair<IdentifierInfo*,WeakInfo> 5735 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5736 } 5737} 5738 5739void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5740 IdentifierInfo* AliasName, 5741 SourceLocation PragmaLoc, 5742 SourceLocation NameLoc, 5743 SourceLocation AliasNameLoc) { 5744 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5745 WeakInfo W = WeakInfo(Name, NameLoc); 5746 5747 if (PrevDecl) { 5748 if (!PrevDecl->hasAttr<AliasAttr>()) 5749 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5750 DeclApplyPragmaWeak(TUScope, ND, W); 5751 } else { 5752 (void)WeakUndeclaredIdentifiers.insert( 5753 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5754 } 5755} 5756