SemaDecl.cpp revision 8b2e5ea5abccc88f29730b8f7f24f5394785b605
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 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1702 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1703 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1704 return false; 1705 } 1706 1707 return true; 1708} 1709 1710Sema::DeclPtrTy 1711Sema::HandleDeclarator(Scope *S, Declarator &D, 1712 MultiTemplateParamsArg TemplateParamLists, 1713 bool IsFunctionDefinition) { 1714 DeclarationName Name = GetNameForDeclarator(D); 1715 1716 // All of these full declarators require an identifier. If it doesn't have 1717 // one, the ParsedFreeStandingDeclSpec action should be used. 1718 if (!Name) { 1719 if (!D.isInvalidType()) // Reject this if we think it is valid. 1720 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1721 diag::err_declarator_need_ident) 1722 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1723 return DeclPtrTy(); 1724 } 1725 1726 // The scope passed in may not be a decl scope. Zip up the scope tree until 1727 // we find one that is. 1728 while ((S->getFlags() & Scope::DeclScope) == 0 || 1729 (S->getFlags() & Scope::TemplateParamScope) != 0) 1730 S = S->getParent(); 1731 1732 // If this is an out-of-line definition of a member of a class template 1733 // or class template partial specialization, we may need to rebuild the 1734 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1735 // for more information. 1736 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1737 // handle expressions properly. 1738 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1739 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1740 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1741 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1742 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1743 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1744 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1745 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1746 // FIXME: Preserve type source info. 1747 QualType T = GetTypeFromParser(DS.getTypeRep()); 1748 EnterDeclaratorContext(S, DC); 1749 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1750 ExitDeclaratorContext(S); 1751 if (T.isNull()) 1752 return DeclPtrTy(); 1753 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1754 } 1755 } 1756 1757 DeclContext *DC; 1758 NamedDecl *PrevDecl; 1759 NamedDecl *New; 1760 1761 DeclaratorInfo *DInfo = 0; 1762 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1763 1764 // See if this is a redefinition of a variable in the same scope. 1765 if (D.getCXXScopeSpec().isInvalid()) { 1766 DC = CurContext; 1767 PrevDecl = 0; 1768 D.setInvalidType(); 1769 } else if (!D.getCXXScopeSpec().isSet()) { 1770 LookupNameKind NameKind = LookupOrdinaryName; 1771 1772 // If the declaration we're planning to build will be a function 1773 // or object with linkage, then look for another declaration with 1774 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1775 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1776 /* Do nothing*/; 1777 else if (R->isFunctionType()) { 1778 if (CurContext->isFunctionOrMethod() || 1779 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1780 NameKind = LookupRedeclarationWithLinkage; 1781 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1782 NameKind = LookupRedeclarationWithLinkage; 1783 else if (CurContext->getLookupContext()->isTranslationUnit() && 1784 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1785 NameKind = LookupRedeclarationWithLinkage; 1786 1787 DC = CurContext; 1788 LookupResult R; 1789 LookupName(R, S, Name, NameKind, true, 1790 NameKind == LookupRedeclarationWithLinkage, 1791 D.getIdentifierLoc()); 1792 PrevDecl = R.getAsSingleDecl(Context); 1793 } else { // Something like "int foo::x;" 1794 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1795 1796 if (!DC) { 1797 // If we could not compute the declaration context, it's because the 1798 // declaration context is dependent but does not refer to a class, 1799 // class template, or class template partial specialization. Complain 1800 // and return early, to avoid the coming semantic disaster. 1801 Diag(D.getIdentifierLoc(), 1802 diag::err_template_qualified_declarator_no_match) 1803 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1804 << D.getCXXScopeSpec().getRange(); 1805 return DeclPtrTy(); 1806 } 1807 1808 if (!DC->isDependentContext() && 1809 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1810 return DeclPtrTy(); 1811 1812 LookupResult Res; 1813 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1814 PrevDecl = Res.getAsSingleDecl(Context); 1815 1816 // C++ 7.3.1.2p2: 1817 // Members (including explicit specializations of templates) of a named 1818 // namespace can also be defined outside that namespace by explicit 1819 // qualification of the name being defined, provided that the entity being 1820 // defined was already declared in the namespace and the definition appears 1821 // after the point of declaration in a namespace that encloses the 1822 // declarations namespace. 1823 // 1824 // Note that we only check the context at this point. We don't yet 1825 // have enough information to make sure that PrevDecl is actually 1826 // the declaration we want to match. For example, given: 1827 // 1828 // class X { 1829 // void f(); 1830 // void f(float); 1831 // }; 1832 // 1833 // void X::f(int) { } // ill-formed 1834 // 1835 // In this case, PrevDecl will point to the overload set 1836 // containing the two f's declared in X, but neither of them 1837 // matches. 1838 1839 // First check whether we named the global scope. 1840 if (isa<TranslationUnitDecl>(DC)) { 1841 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1842 << Name << D.getCXXScopeSpec().getRange(); 1843 } else { 1844 DeclContext *Cur = CurContext; 1845 while (isa<LinkageSpecDecl>(Cur)) 1846 Cur = Cur->getParent(); 1847 if (!Cur->Encloses(DC)) { 1848 // The qualifying scope doesn't enclose the original declaration. 1849 // Emit diagnostic based on current scope. 1850 SourceLocation L = D.getIdentifierLoc(); 1851 SourceRange R = D.getCXXScopeSpec().getRange(); 1852 if (isa<FunctionDecl>(Cur)) 1853 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1854 else 1855 Diag(L, diag::err_invalid_declarator_scope) 1856 << Name << cast<NamedDecl>(DC) << R; 1857 D.setInvalidType(); 1858 } 1859 } 1860 } 1861 1862 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1863 // Maybe we will complain about the shadowed template parameter. 1864 if (!D.isInvalidType()) 1865 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1866 D.setInvalidType(); 1867 1868 // Just pretend that we didn't see the previous declaration. 1869 PrevDecl = 0; 1870 } 1871 1872 // In C++, the previous declaration we find might be a tag type 1873 // (class or enum). In this case, the new declaration will hide the 1874 // tag type. Note that this does does not apply if we're declaring a 1875 // typedef (C++ [dcl.typedef]p4). 1876 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1877 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1878 PrevDecl = 0; 1879 1880 bool Redeclaration = false; 1881 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1882 if (TemplateParamLists.size()) { 1883 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1884 return DeclPtrTy(); 1885 } 1886 1887 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1888 } else if (R->isFunctionType()) { 1889 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1890 move(TemplateParamLists), 1891 IsFunctionDefinition, Redeclaration); 1892 } else { 1893 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1894 move(TemplateParamLists), 1895 Redeclaration); 1896 } 1897 1898 if (New == 0) 1899 return DeclPtrTy(); 1900 1901 // If this has an identifier and is not an invalid redeclaration or 1902 // function template specialization, add it to the scope stack. 1903 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1904 !(isa<FunctionDecl>(New) && 1905 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1906 PushOnScopeChains(New, S); 1907 1908 return DeclPtrTy::make(New); 1909} 1910 1911/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1912/// types into constant array types in certain situations which would otherwise 1913/// be errors (for GCC compatibility). 1914static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1915 ASTContext &Context, 1916 bool &SizeIsNegative) { 1917 // This method tries to turn a variable array into a constant 1918 // array even when the size isn't an ICE. This is necessary 1919 // for compatibility with code that depends on gcc's buggy 1920 // constant expression folding, like struct {char x[(int)(char*)2];} 1921 SizeIsNegative = false; 1922 1923 QualifierCollector Qs; 1924 const Type *Ty = Qs.strip(T); 1925 1926 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1927 QualType Pointee = PTy->getPointeeType(); 1928 QualType FixedType = 1929 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1930 if (FixedType.isNull()) return FixedType; 1931 FixedType = Context.getPointerType(FixedType); 1932 return Qs.apply(FixedType); 1933 } 1934 1935 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1936 if (!VLATy) 1937 return QualType(); 1938 // FIXME: We should probably handle this case 1939 if (VLATy->getElementType()->isVariablyModifiedType()) 1940 return QualType(); 1941 1942 Expr::EvalResult EvalResult; 1943 if (!VLATy->getSizeExpr() || 1944 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1945 !EvalResult.Val.isInt()) 1946 return QualType(); 1947 1948 llvm::APSInt &Res = EvalResult.Val.getInt(); 1949 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1950 // TODO: preserve the size expression in declarator info 1951 return Context.getConstantArrayType(VLATy->getElementType(), 1952 Res, ArrayType::Normal, 0); 1953 } 1954 1955 SizeIsNegative = true; 1956 return QualType(); 1957} 1958 1959/// \brief Register the given locally-scoped external C declaration so 1960/// that it can be found later for redeclarations 1961void 1962Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1963 Scope *S) { 1964 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1965 "Decl is not a locally-scoped decl!"); 1966 // Note that we have a locally-scoped external with this name. 1967 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1968 1969 if (!PrevDecl) 1970 return; 1971 1972 // If there was a previous declaration of this variable, it may be 1973 // in our identifier chain. Update the identifier chain with the new 1974 // declaration. 1975 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1976 // The previous declaration was found on the identifer resolver 1977 // chain, so remove it from its scope. 1978 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1979 S = S->getParent(); 1980 1981 if (S) 1982 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1983 } 1984} 1985 1986/// \brief Diagnose function specifiers on a declaration of an identifier that 1987/// does not identify a function. 1988void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1989 // FIXME: We should probably indicate the identifier in question to avoid 1990 // confusion for constructs like "inline int a(), b;" 1991 if (D.getDeclSpec().isInlineSpecified()) 1992 Diag(D.getDeclSpec().getInlineSpecLoc(), 1993 diag::err_inline_non_function); 1994 1995 if (D.getDeclSpec().isVirtualSpecified()) 1996 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1997 diag::err_virtual_non_function); 1998 1999 if (D.getDeclSpec().isExplicitSpecified()) 2000 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2001 diag::err_explicit_non_function); 2002} 2003 2004NamedDecl* 2005Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2006 QualType R, DeclaratorInfo *DInfo, 2007 NamedDecl* PrevDecl, bool &Redeclaration) { 2008 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2009 if (D.getCXXScopeSpec().isSet()) { 2010 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2011 << D.getCXXScopeSpec().getRange(); 2012 D.setInvalidType(); 2013 // Pretend we didn't see the scope specifier. 2014 DC = 0; 2015 } 2016 2017 if (getLangOptions().CPlusPlus) { 2018 // Check that there are no default arguments (C++ only). 2019 CheckExtraCXXDefaultArguments(D); 2020 } 2021 2022 DiagnoseFunctionSpecifiers(D); 2023 2024 if (D.getDeclSpec().isThreadSpecified()) 2025 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2026 2027 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 2028 if (!NewTD) return 0; 2029 2030 // Handle attributes prior to checking for duplicates in MergeVarDecl 2031 ProcessDeclAttributes(S, NewTD, D); 2032 // Merge the decl with the existing one if appropriate. If the decl is 2033 // in an outer scope, it isn't the same thing. 2034 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2035 Redeclaration = true; 2036 MergeTypeDefDecl(NewTD, PrevDecl); 2037 } 2038 2039 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2040 // then it shall have block scope. 2041 QualType T = NewTD->getUnderlyingType(); 2042 if (T->isVariablyModifiedType()) { 2043 CurFunctionNeedsScopeChecking = true; 2044 2045 if (S->getFnParent() == 0) { 2046 bool SizeIsNegative; 2047 QualType FixedTy = 2048 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2049 if (!FixedTy.isNull()) { 2050 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2051 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2052 } else { 2053 if (SizeIsNegative) 2054 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2055 else if (T->isVariableArrayType()) 2056 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2057 else 2058 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2059 NewTD->setInvalidDecl(); 2060 } 2061 } 2062 } 2063 2064 // If this is the C FILE type, notify the AST context. 2065 if (IdentifierInfo *II = NewTD->getIdentifier()) 2066 if (!NewTD->isInvalidDecl() && 2067 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2068 if (II->isStr("FILE")) 2069 Context.setFILEDecl(NewTD); 2070 else if (II->isStr("jmp_buf")) 2071 Context.setjmp_bufDecl(NewTD); 2072 else if (II->isStr("sigjmp_buf")) 2073 Context.setsigjmp_bufDecl(NewTD); 2074 } 2075 2076 return NewTD; 2077} 2078 2079/// \brief Determines whether the given declaration is an out-of-scope 2080/// previous declaration. 2081/// 2082/// This routine should be invoked when name lookup has found a 2083/// previous declaration (PrevDecl) that is not in the scope where a 2084/// new declaration by the same name is being introduced. If the new 2085/// declaration occurs in a local scope, previous declarations with 2086/// linkage may still be considered previous declarations (C99 2087/// 6.2.2p4-5, C++ [basic.link]p6). 2088/// 2089/// \param PrevDecl the previous declaration found by name 2090/// lookup 2091/// 2092/// \param DC the context in which the new declaration is being 2093/// declared. 2094/// 2095/// \returns true if PrevDecl is an out-of-scope previous declaration 2096/// for a new delcaration with the same name. 2097static bool 2098isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2099 ASTContext &Context) { 2100 if (!PrevDecl) 2101 return 0; 2102 2103 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2104 // case we need to check each of the overloaded functions. 2105 if (!PrevDecl->hasLinkage()) 2106 return false; 2107 2108 if (Context.getLangOptions().CPlusPlus) { 2109 // C++ [basic.link]p6: 2110 // If there is a visible declaration of an entity with linkage 2111 // having the same name and type, ignoring entities declared 2112 // outside the innermost enclosing namespace scope, the block 2113 // scope declaration declares that same entity and receives the 2114 // linkage of the previous declaration. 2115 DeclContext *OuterContext = DC->getLookupContext(); 2116 if (!OuterContext->isFunctionOrMethod()) 2117 // This rule only applies to block-scope declarations. 2118 return false; 2119 else { 2120 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2121 if (PrevOuterContext->isRecord()) 2122 // We found a member function: ignore it. 2123 return false; 2124 else { 2125 // Find the innermost enclosing namespace for the new and 2126 // previous declarations. 2127 while (!OuterContext->isFileContext()) 2128 OuterContext = OuterContext->getParent(); 2129 while (!PrevOuterContext->isFileContext()) 2130 PrevOuterContext = PrevOuterContext->getParent(); 2131 2132 // The previous declaration is in a different namespace, so it 2133 // isn't the same function. 2134 if (OuterContext->getPrimaryContext() != 2135 PrevOuterContext->getPrimaryContext()) 2136 return false; 2137 } 2138 } 2139 } 2140 2141 return true; 2142} 2143 2144NamedDecl* 2145Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2146 QualType R, DeclaratorInfo *DInfo, 2147 NamedDecl* PrevDecl, 2148 MultiTemplateParamsArg TemplateParamLists, 2149 bool &Redeclaration) { 2150 DeclarationName Name = GetNameForDeclarator(D); 2151 2152 // Check that there are no default arguments (C++ only). 2153 if (getLangOptions().CPlusPlus) 2154 CheckExtraCXXDefaultArguments(D); 2155 2156 VarDecl *NewVD; 2157 VarDecl::StorageClass SC; 2158 switch (D.getDeclSpec().getStorageClassSpec()) { 2159 default: assert(0 && "Unknown storage class!"); 2160 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2161 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2162 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2163 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2164 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2165 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2166 case DeclSpec::SCS_mutable: 2167 // mutable can only appear on non-static class members, so it's always 2168 // an error here 2169 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2170 D.setInvalidType(); 2171 SC = VarDecl::None; 2172 break; 2173 } 2174 2175 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2176 if (!II) { 2177 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2178 << Name.getAsString(); 2179 return 0; 2180 } 2181 2182 DiagnoseFunctionSpecifiers(D); 2183 2184 if (!DC->isRecord() && S->getFnParent() == 0) { 2185 // C99 6.9p2: The storage-class specifiers auto and register shall not 2186 // appear in the declaration specifiers in an external declaration. 2187 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2188 2189 // If this is a register variable with an asm label specified, then this 2190 // is a GNU extension. 2191 if (SC == VarDecl::Register && D.getAsmLabel()) 2192 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2193 else 2194 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2195 D.setInvalidType(); 2196 } 2197 } 2198 if (DC->isRecord() && !CurContext->isRecord()) { 2199 // This is an out-of-line definition of a static data member. 2200 if (SC == VarDecl::Static) { 2201 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2202 diag::err_static_out_of_line) 2203 << CodeModificationHint::CreateRemoval( 2204 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2205 } else if (SC == VarDecl::None) 2206 SC = VarDecl::Static; 2207 } 2208 if (SC == VarDecl::Static) { 2209 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2210 if (RD->isLocalClass()) 2211 Diag(D.getIdentifierLoc(), 2212 diag::err_static_data_member_not_allowed_in_local_class) 2213 << Name << RD->getDeclName(); 2214 } 2215 } 2216 2217 // Match up the template parameter lists with the scope specifier, then 2218 // determine whether we have a template or a template specialization. 2219 bool isExplicitSpecialization = false; 2220 if (TemplateParameterList *TemplateParams 2221 = MatchTemplateParametersToScopeSpecifier( 2222 D.getDeclSpec().getSourceRange().getBegin(), 2223 D.getCXXScopeSpec(), 2224 (TemplateParameterList**)TemplateParamLists.get(), 2225 TemplateParamLists.size(), 2226 isExplicitSpecialization)) { 2227 if (TemplateParams->size() > 0) { 2228 // There is no such thing as a variable template. 2229 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2230 << II 2231 << SourceRange(TemplateParams->getTemplateLoc(), 2232 TemplateParams->getRAngleLoc()); 2233 return 0; 2234 } else { 2235 // There is an extraneous 'template<>' for this variable. Complain 2236 // about it, but allow the declaration of the variable. 2237 Diag(TemplateParams->getTemplateLoc(), 2238 diag::err_template_variable_noparams) 2239 << II 2240 << SourceRange(TemplateParams->getTemplateLoc(), 2241 TemplateParams->getRAngleLoc()); 2242 2243 isExplicitSpecialization = true; 2244 } 2245 } 2246 2247 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2248 II, R, DInfo, SC); 2249 2250 if (D.isInvalidType()) 2251 NewVD->setInvalidDecl(); 2252 2253 if (D.getDeclSpec().isThreadSpecified()) { 2254 if (NewVD->hasLocalStorage()) 2255 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2256 else if (!Context.Target.isTLSSupported()) 2257 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2258 else 2259 NewVD->setThreadSpecified(true); 2260 } 2261 2262 // Set the lexical context. If the declarator has a C++ scope specifier, the 2263 // lexical context will be different from the semantic context. 2264 NewVD->setLexicalDeclContext(CurContext); 2265 2266 // Handle attributes prior to checking for duplicates in MergeVarDecl 2267 ProcessDeclAttributes(S, NewVD, D); 2268 2269 // Handle GNU asm-label extension (encoded as an attribute). 2270 if (Expr *E = (Expr*) D.getAsmLabel()) { 2271 // The parser guarantees this is a string. 2272 StringLiteral *SE = cast<StringLiteral>(E); 2273 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2274 SE->getByteLength()))); 2275 } 2276 2277 // If name lookup finds a previous declaration that is not in the 2278 // same scope as the new declaration, this may still be an 2279 // acceptable redeclaration. 2280 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2281 !(NewVD->hasLinkage() && 2282 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2283 PrevDecl = 0; 2284 2285 // Merge the decl with the existing one if appropriate. 2286 if (PrevDecl) { 2287 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2288 // The user tried to define a non-static data member 2289 // out-of-line (C++ [dcl.meaning]p1). 2290 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2291 << D.getCXXScopeSpec().getRange(); 2292 PrevDecl = 0; 2293 NewVD->setInvalidDecl(); 2294 } 2295 } else if (D.getCXXScopeSpec().isSet()) { 2296 // No previous declaration in the qualifying scope. 2297 Diag(D.getIdentifierLoc(), diag::err_no_member) 2298 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2299 << D.getCXXScopeSpec().getRange(); 2300 NewVD->setInvalidDecl(); 2301 } 2302 2303 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2304 2305 // This is an explicit specialization of a static data member. Check it. 2306 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2307 CheckMemberSpecialization(NewVD, PrevDecl)) 2308 NewVD->setInvalidDecl(); 2309 2310 // attributes declared post-definition are currently ignored 2311 if (PrevDecl) { 2312 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2313 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2314 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2315 Diag(Def->getLocation(), diag::note_previous_definition); 2316 } 2317 } 2318 2319 // If this is a locally-scoped extern C variable, update the map of 2320 // such variables. 2321 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2322 !NewVD->isInvalidDecl()) 2323 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2324 2325 return NewVD; 2326} 2327 2328/// \brief Perform semantic checking on a newly-created variable 2329/// declaration. 2330/// 2331/// This routine performs all of the type-checking required for a 2332/// variable declaration once it has been built. It is used both to 2333/// check variables after they have been parsed and their declarators 2334/// have been translated into a declaration, and to check variables 2335/// that have been instantiated from a template. 2336/// 2337/// Sets NewVD->isInvalidDecl() if an error was encountered. 2338void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2339 bool &Redeclaration) { 2340 // If the decl is already known invalid, don't check it. 2341 if (NewVD->isInvalidDecl()) 2342 return; 2343 2344 QualType T = NewVD->getType(); 2345 2346 if (T->isObjCInterfaceType()) { 2347 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2348 return NewVD->setInvalidDecl(); 2349 } 2350 2351 // The variable can not have an abstract class type. 2352 if (RequireNonAbstractType(NewVD->getLocation(), T, 2353 diag::err_abstract_type_in_decl, 2354 AbstractVariableType)) 2355 return NewVD->setInvalidDecl(); 2356 2357 // Emit an error if an address space was applied to decl with local storage. 2358 // This includes arrays of objects with address space qualifiers, but not 2359 // automatic variables that point to other address spaces. 2360 // ISO/IEC TR 18037 S5.1.2 2361 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2362 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2363 return NewVD->setInvalidDecl(); 2364 } 2365 2366 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2367 && !NewVD->hasAttr<BlocksAttr>()) 2368 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2369 2370 bool isVM = T->isVariablyModifiedType(); 2371 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2372 NewVD->hasAttr<BlocksAttr>()) 2373 CurFunctionNeedsScopeChecking = true; 2374 2375 if ((isVM && NewVD->hasLinkage()) || 2376 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2377 bool SizeIsNegative; 2378 QualType FixedTy = 2379 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2380 2381 if (FixedTy.isNull() && T->isVariableArrayType()) { 2382 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2383 // FIXME: This won't give the correct result for 2384 // int a[10][n]; 2385 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2386 2387 if (NewVD->isFileVarDecl()) 2388 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2389 << SizeRange; 2390 else if (NewVD->getStorageClass() == VarDecl::Static) 2391 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2392 << SizeRange; 2393 else 2394 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2395 << SizeRange; 2396 return NewVD->setInvalidDecl(); 2397 } 2398 2399 if (FixedTy.isNull()) { 2400 if (NewVD->isFileVarDecl()) 2401 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2402 else 2403 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2404 return NewVD->setInvalidDecl(); 2405 } 2406 2407 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2408 NewVD->setType(FixedTy); 2409 } 2410 2411 if (!PrevDecl && NewVD->isExternC()) { 2412 // Since we did not find anything by this name and we're declaring 2413 // an extern "C" variable, look for a non-visible extern "C" 2414 // declaration with the same name. 2415 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2416 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2417 if (Pos != LocallyScopedExternalDecls.end()) 2418 PrevDecl = Pos->second; 2419 } 2420 2421 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2422 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2423 << T; 2424 return NewVD->setInvalidDecl(); 2425 } 2426 2427 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2428 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2429 return NewVD->setInvalidDecl(); 2430 } 2431 2432 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2433 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2434 return NewVD->setInvalidDecl(); 2435 } 2436 2437 if (PrevDecl) { 2438 Redeclaration = true; 2439 MergeVarDecl(NewVD, PrevDecl); 2440 } 2441} 2442 2443static bool isUsingDecl(Decl *D) { 2444 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2445} 2446 2447/// \brief Data used with FindOverriddenMethod 2448struct FindOverriddenMethodData { 2449 Sema *S; 2450 CXXMethodDecl *Method; 2451}; 2452 2453/// \brief Member lookup function that determines whether a given C++ 2454/// method overrides a method in a base class, to be used with 2455/// CXXRecordDecl::lookupInBases(). 2456static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2457 CXXBasePath &Path, 2458 void *UserData) { 2459 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2460 2461 FindOverriddenMethodData *Data 2462 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2463 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2464 Path.Decls.first != Path.Decls.second; 2465 ++Path.Decls.first) { 2466 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2467 OverloadedFunctionDecl::function_iterator MatchedDecl; 2468 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2469 return true; 2470 } 2471 } 2472 2473 return false; 2474} 2475 2476NamedDecl* 2477Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2478 QualType R, DeclaratorInfo *DInfo, 2479 NamedDecl* PrevDecl, 2480 MultiTemplateParamsArg TemplateParamLists, 2481 bool IsFunctionDefinition, bool &Redeclaration) { 2482 assert(R.getTypePtr()->isFunctionType()); 2483 2484 DeclarationName Name = GetNameForDeclarator(D); 2485 FunctionDecl::StorageClass SC = FunctionDecl::None; 2486 switch (D.getDeclSpec().getStorageClassSpec()) { 2487 default: assert(0 && "Unknown storage class!"); 2488 case DeclSpec::SCS_auto: 2489 case DeclSpec::SCS_register: 2490 case DeclSpec::SCS_mutable: 2491 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2492 diag::err_typecheck_sclass_func); 2493 D.setInvalidType(); 2494 break; 2495 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2496 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2497 case DeclSpec::SCS_static: { 2498 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2499 // C99 6.7.1p5: 2500 // The declaration of an identifier for a function that has 2501 // block scope shall have no explicit storage-class specifier 2502 // other than extern 2503 // See also (C++ [dcl.stc]p4). 2504 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2505 diag::err_static_block_func); 2506 SC = FunctionDecl::None; 2507 } else 2508 SC = FunctionDecl::Static; 2509 break; 2510 } 2511 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2512 } 2513 2514 if (D.getDeclSpec().isThreadSpecified()) 2515 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2516 2517 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2518 bool isInline = D.getDeclSpec().isInlineSpecified(); 2519 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2520 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2521 2522 // Check that the return type is not an abstract class type. 2523 // For record types, this is done by the AbstractClassUsageDiagnoser once 2524 // the class has been completely parsed. 2525 if (!DC->isRecord() && 2526 RequireNonAbstractType(D.getIdentifierLoc(), 2527 R->getAs<FunctionType>()->getResultType(), 2528 diag::err_abstract_type_in_decl, 2529 AbstractReturnType)) 2530 D.setInvalidType(); 2531 2532 // Do not allow returning a objc interface by-value. 2533 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2534 Diag(D.getIdentifierLoc(), 2535 diag::err_object_cannot_be_passed_returned_by_value) << 0 2536 << R->getAs<FunctionType>()->getResultType(); 2537 D.setInvalidType(); 2538 } 2539 2540 bool isVirtualOkay = false; 2541 FunctionDecl *NewFD; 2542 2543 if (isFriend) { 2544 // DC is the namespace in which the function is being declared. 2545 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2546 "friend function being created in a non-namespace context"); 2547 2548 // C++ [class.friend]p5 2549 // A function can be defined in a friend declaration of a 2550 // class . . . . Such a function is implicitly inline. 2551 isInline |= IsFunctionDefinition; 2552 } 2553 2554 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2555 // This is a C++ constructor declaration. 2556 assert(DC->isRecord() && 2557 "Constructors can only be declared in a member context"); 2558 2559 R = CheckConstructorDeclarator(D, R, SC); 2560 2561 // Create the new declaration 2562 NewFD = CXXConstructorDecl::Create(Context, 2563 cast<CXXRecordDecl>(DC), 2564 D.getIdentifierLoc(), Name, R, DInfo, 2565 isExplicit, isInline, 2566 /*isImplicitlyDeclared=*/false); 2567 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2568 // This is a C++ destructor declaration. 2569 if (DC->isRecord()) { 2570 R = CheckDestructorDeclarator(D, SC); 2571 2572 NewFD = CXXDestructorDecl::Create(Context, 2573 cast<CXXRecordDecl>(DC), 2574 D.getIdentifierLoc(), Name, R, 2575 isInline, 2576 /*isImplicitlyDeclared=*/false); 2577 2578 isVirtualOkay = true; 2579 } else { 2580 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2581 2582 // Create a FunctionDecl to satisfy the function definition parsing 2583 // code path. 2584 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2585 Name, R, DInfo, SC, isInline, 2586 /*hasPrototype=*/true); 2587 D.setInvalidType(); 2588 } 2589 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2590 if (!DC->isRecord()) { 2591 Diag(D.getIdentifierLoc(), 2592 diag::err_conv_function_not_member); 2593 return 0; 2594 } 2595 2596 CheckConversionDeclarator(D, R, SC); 2597 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2598 D.getIdentifierLoc(), Name, R, DInfo, 2599 isInline, isExplicit); 2600 2601 isVirtualOkay = true; 2602 } else if (DC->isRecord()) { 2603 // If the of the function is the same as the name of the record, then this 2604 // must be an invalid constructor that has a return type. 2605 // (The parser checks for a return type and makes the declarator a 2606 // constructor if it has no return type). 2607 // must have an invalid constructor that has a return type 2608 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2609 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2610 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2611 << SourceRange(D.getIdentifierLoc()); 2612 return 0; 2613 } 2614 2615 bool isStatic = SC == FunctionDecl::Static; 2616 2617 // [class.free]p1: 2618 // Any allocation function for a class T is a static member 2619 // (even if not explicitly declared static). 2620 if (Name.getCXXOverloadedOperator() == OO_New || 2621 Name.getCXXOverloadedOperator() == OO_Array_New) 2622 isStatic = true; 2623 2624 // [class.free]p6 Any deallocation function for a class X is a static member 2625 // (even if not explicitly declared static). 2626 if (Name.getCXXOverloadedOperator() == OO_Delete || 2627 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2628 isStatic = true; 2629 2630 // This is a C++ method declaration. 2631 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2632 D.getIdentifierLoc(), Name, R, DInfo, 2633 isStatic, isInline); 2634 2635 isVirtualOkay = !isStatic; 2636 } else { 2637 // Determine whether the function was written with a 2638 // prototype. This true when: 2639 // - we're in C++ (where every function has a prototype), 2640 // - there is a prototype in the declarator, or 2641 // - the type R of the function is some kind of typedef or other reference 2642 // to a type name (which eventually refers to a function type). 2643 bool HasPrototype = 2644 getLangOptions().CPlusPlus || 2645 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2646 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2647 2648 NewFD = FunctionDecl::Create(Context, DC, 2649 D.getIdentifierLoc(), 2650 Name, R, DInfo, SC, isInline, HasPrototype); 2651 } 2652 2653 if (D.isInvalidType()) 2654 NewFD->setInvalidDecl(); 2655 2656 // Set the lexical context. If the declarator has a C++ 2657 // scope specifier, or is the object of a friend declaration, the 2658 // lexical context will be different from the semantic context. 2659 NewFD->setLexicalDeclContext(CurContext); 2660 2661 // Match up the template parameter lists with the scope specifier, then 2662 // determine whether we have a template or a template specialization. 2663 FunctionTemplateDecl *FunctionTemplate = 0; 2664 bool isExplicitSpecialization = false; 2665 bool isFunctionTemplateSpecialization = false; 2666 if (TemplateParameterList *TemplateParams 2667 = MatchTemplateParametersToScopeSpecifier( 2668 D.getDeclSpec().getSourceRange().getBegin(), 2669 D.getCXXScopeSpec(), 2670 (TemplateParameterList**)TemplateParamLists.get(), 2671 TemplateParamLists.size(), 2672 isExplicitSpecialization)) { 2673 if (TemplateParams->size() > 0) { 2674 // This is a function template 2675 2676 // Check that we can declare a template here. 2677 if (CheckTemplateDeclScope(S, TemplateParams)) 2678 return 0; 2679 2680 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2681 NewFD->getLocation(), 2682 Name, TemplateParams, 2683 NewFD); 2684 FunctionTemplate->setLexicalDeclContext(CurContext); 2685 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2686 } else { 2687 // This is a function template specialization. 2688 isFunctionTemplateSpecialization = true; 2689 } 2690 2691 // FIXME: Free this memory properly. 2692 TemplateParamLists.release(); 2693 } 2694 2695 // C++ [dcl.fct.spec]p5: 2696 // The virtual specifier shall only be used in declarations of 2697 // nonstatic class member functions that appear within a 2698 // member-specification of a class declaration; see 10.3. 2699 // 2700 if (isVirtual && !NewFD->isInvalidDecl()) { 2701 if (!isVirtualOkay) { 2702 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2703 diag::err_virtual_non_function); 2704 } else if (!CurContext->isRecord()) { 2705 // 'virtual' was specified outside of the class. 2706 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2707 << CodeModificationHint::CreateRemoval( 2708 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2709 } else { 2710 // Okay: Add virtual to the method. 2711 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2712 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2713 CurClass->setAggregate(false); 2714 CurClass->setPOD(false); 2715 CurClass->setEmpty(false); 2716 CurClass->setPolymorphic(true); 2717 CurClass->setHasTrivialConstructor(false); 2718 CurClass->setHasTrivialCopyConstructor(false); 2719 CurClass->setHasTrivialCopyAssignment(false); 2720 } 2721 } 2722 2723 if (isFriend) { 2724 if (FunctionTemplate) { 2725 FunctionTemplate->setObjectOfFriendDecl( 2726 /* PreviouslyDeclared= */ PrevDecl != NULL); 2727 FunctionTemplate->setAccess(AS_public); 2728 } 2729 else 2730 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2731 2732 NewFD->setAccess(AS_public); 2733 } 2734 2735 2736 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2737 // Look for virtual methods in base classes that this method might override. 2738 CXXBasePaths Paths; 2739 FindOverriddenMethodData Data; 2740 Data.Method = NewMD; 2741 Data.S = this; 2742 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2743 Paths)) { 2744 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2745 E = Paths.found_decls_end(); I != E; ++I) { 2746 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2747 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2748 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2749 NewMD->addOverriddenMethod(OldMD); 2750 } 2751 } 2752 } 2753 } 2754 2755 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2756 !CurContext->isRecord()) { 2757 // C++ [class.static]p1: 2758 // A data or function member of a class may be declared static 2759 // in a class definition, in which case it is a static member of 2760 // the class. 2761 2762 // Complain about the 'static' specifier if it's on an out-of-line 2763 // member function definition. 2764 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2765 diag::err_static_out_of_line) 2766 << CodeModificationHint::CreateRemoval( 2767 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2768 } 2769 2770 // Handle GNU asm-label extension (encoded as an attribute). 2771 if (Expr *E = (Expr*) D.getAsmLabel()) { 2772 // The parser guarantees this is a string. 2773 StringLiteral *SE = cast<StringLiteral>(E); 2774 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2775 SE->getByteLength()))); 2776 } 2777 2778 // Copy the parameter declarations from the declarator D to the function 2779 // declaration NewFD, if they are available. First scavenge them into Params. 2780 llvm::SmallVector<ParmVarDecl*, 16> Params; 2781 if (D.getNumTypeObjects() > 0) { 2782 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2783 2784 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2785 // function that takes no arguments, not a function that takes a 2786 // single void argument. 2787 // We let through "const void" here because Sema::GetTypeForDeclarator 2788 // already checks for that case. 2789 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2790 FTI.ArgInfo[0].Param && 2791 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2792 // Empty arg list, don't push any params. 2793 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2794 2795 // In C++, the empty parameter-type-list must be spelled "void"; a 2796 // typedef of void is not permitted. 2797 if (getLangOptions().CPlusPlus && 2798 Param->getType().getUnqualifiedType() != Context.VoidTy) 2799 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2800 // FIXME: Leaks decl? 2801 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2802 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2803 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2804 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2805 Param->setDeclContext(NewFD); 2806 Params.push_back(Param); 2807 } 2808 } 2809 2810 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2811 // When we're declaring a function with a typedef, typeof, etc as in the 2812 // following example, we'll need to synthesize (unnamed) 2813 // parameters for use in the declaration. 2814 // 2815 // @code 2816 // typedef void fn(int); 2817 // fn f; 2818 // @endcode 2819 2820 // Synthesize a parameter for each argument type. 2821 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2822 AE = FT->arg_type_end(); AI != AE; ++AI) { 2823 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2824 SourceLocation(), 0, 2825 *AI, /*DInfo=*/0, 2826 VarDecl::None, 0); 2827 Param->setImplicit(); 2828 Params.push_back(Param); 2829 } 2830 } else { 2831 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2832 "Should not need args for typedef of non-prototype fn"); 2833 } 2834 // Finally, we know we have the right number of parameters, install them. 2835 NewFD->setParams(Context, Params.data(), Params.size()); 2836 2837 // If name lookup finds a previous declaration that is not in the 2838 // same scope as the new declaration, this may still be an 2839 // acceptable redeclaration. 2840 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2841 !(NewFD->hasLinkage() && 2842 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2843 PrevDecl = 0; 2844 2845 // If the declarator is a template-id, translate the parser's template 2846 // argument list into our AST format. 2847 bool HasExplicitTemplateArgs = false; 2848 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 2849 SourceLocation LAngleLoc, RAngleLoc; 2850 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2851 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2852 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2853 TemplateId->getTemplateArgs(), 2854 TemplateId->NumArgs); 2855 translateTemplateArguments(TemplateArgsPtr, 2856 TemplateArgs); 2857 TemplateArgsPtr.release(); 2858 2859 HasExplicitTemplateArgs = true; 2860 LAngleLoc = TemplateId->LAngleLoc; 2861 RAngleLoc = TemplateId->RAngleLoc; 2862 2863 if (FunctionTemplate) { 2864 // FIXME: Diagnose function template with explicit template 2865 // arguments. 2866 HasExplicitTemplateArgs = false; 2867 } else if (!isFunctionTemplateSpecialization && 2868 !D.getDeclSpec().isFriendSpecified()) { 2869 // We have encountered something that the user meant to be a 2870 // specialization (because it has explicitly-specified template 2871 // arguments) but that was not introduced with a "template<>" (or had 2872 // too few of them). 2873 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2874 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2875 << CodeModificationHint::CreateInsertion( 2876 D.getDeclSpec().getSourceRange().getBegin(), 2877 "template<> "); 2878 isFunctionTemplateSpecialization = true; 2879 } 2880 } 2881 2882 if (isFunctionTemplateSpecialization) { 2883 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2884 LAngleLoc, TemplateArgs.data(), 2885 TemplateArgs.size(), RAngleLoc, 2886 PrevDecl)) 2887 NewFD->setInvalidDecl(); 2888 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2889 CheckMemberSpecialization(NewFD, PrevDecl)) 2890 NewFD->setInvalidDecl(); 2891 2892 // Perform semantic checking on the function declaration. 2893 bool OverloadableAttrRequired = false; // FIXME: HACK! 2894 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2895 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2896 2897 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2898 // An out-of-line member function declaration must also be a 2899 // definition (C++ [dcl.meaning]p1). 2900 // Note that this is not the case for explicit specializations of 2901 // function templates or member functions of class templates, per 2902 // C++ [temp.expl.spec]p2. 2903 if (!IsFunctionDefinition && !isFriend && 2904 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2905 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2906 << D.getCXXScopeSpec().getRange(); 2907 NewFD->setInvalidDecl(); 2908 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2909 // The user tried to provide an out-of-line definition for a 2910 // function that is a member of a class or namespace, but there 2911 // was no such member function declared (C++ [class.mfct]p2, 2912 // C++ [namespace.memdef]p2). For example: 2913 // 2914 // class X { 2915 // void f() const; 2916 // }; 2917 // 2918 // void X::f() { } // ill-formed 2919 // 2920 // Complain about this problem, and attempt to suggest close 2921 // matches (e.g., those that differ only in cv-qualifiers and 2922 // whether the parameter types are references). 2923 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2924 << Name << DC << D.getCXXScopeSpec().getRange(); 2925 NewFD->setInvalidDecl(); 2926 2927 LookupResult Prev; 2928 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2929 assert(!Prev.isAmbiguous() && 2930 "Cannot have an ambiguity in previous-declaration lookup"); 2931 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2932 Func != FuncEnd; ++Func) { 2933 if (isa<FunctionDecl>(*Func) && 2934 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2935 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2936 } 2937 2938 PrevDecl = 0; 2939 } 2940 } 2941 2942 // Handle attributes. We need to have merged decls when handling attributes 2943 // (for example to check for conflicts, etc). 2944 // FIXME: This needs to happen before we merge declarations. Then, 2945 // let attribute merging cope with attribute conflicts. 2946 ProcessDeclAttributes(S, NewFD, D); 2947 2948 // attributes declared post-definition are currently ignored 2949 if (Redeclaration && PrevDecl) { 2950 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2951 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2952 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2953 Diag(Def->getLocation(), diag::note_previous_definition); 2954 } 2955 } 2956 2957 AddKnownFunctionAttributes(NewFD); 2958 2959 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2960 // If a function name is overloadable in C, then every function 2961 // with that name must be marked "overloadable". 2962 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2963 << Redeclaration << NewFD; 2964 if (PrevDecl) 2965 Diag(PrevDecl->getLocation(), 2966 diag::note_attribute_overloadable_prev_overload); 2967 NewFD->addAttr(::new (Context) OverloadableAttr()); 2968 } 2969 2970 // If this is a locally-scoped extern C function, update the 2971 // map of such names. 2972 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2973 && !NewFD->isInvalidDecl()) 2974 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2975 2976 // Set this FunctionDecl's range up to the right paren. 2977 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2978 2979 if (FunctionTemplate && NewFD->isInvalidDecl()) 2980 FunctionTemplate->setInvalidDecl(); 2981 2982 if (FunctionTemplate) 2983 return FunctionTemplate; 2984 2985 return NewFD; 2986} 2987 2988/// \brief Perform semantic checking of a new function declaration. 2989/// 2990/// Performs semantic analysis of the new function declaration 2991/// NewFD. This routine performs all semantic checking that does not 2992/// require the actual declarator involved in the declaration, and is 2993/// used both for the declaration of functions as they are parsed 2994/// (called via ActOnDeclarator) and for the declaration of functions 2995/// that have been instantiated via C++ template instantiation (called 2996/// via InstantiateDecl). 2997/// 2998/// \param IsExplicitSpecialiation whether this new function declaration is 2999/// an explicit specialization of the previous declaration. 3000/// 3001/// This sets NewFD->isInvalidDecl() to true if there was an error. 3002void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 3003 bool IsExplicitSpecialization, 3004 bool &Redeclaration, 3005 bool &OverloadableAttrRequired) { 3006 // If NewFD is already known erroneous, don't do any of this checking. 3007 if (NewFD->isInvalidDecl()) 3008 return; 3009 3010 if (NewFD->getResultType()->isVariablyModifiedType()) { 3011 // Functions returning a variably modified type violate C99 6.7.5.2p2 3012 // because all functions have linkage. 3013 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3014 return NewFD->setInvalidDecl(); 3015 } 3016 3017 if (NewFD->isMain()) 3018 CheckMain(NewFD); 3019 3020 // Check for a previous declaration of this name. 3021 if (!PrevDecl && NewFD->isExternC()) { 3022 // Since we did not find anything by this name and we're declaring 3023 // an extern "C" function, look for a non-visible extern "C" 3024 // declaration with the same name. 3025 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3026 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3027 if (Pos != LocallyScopedExternalDecls.end()) 3028 PrevDecl = Pos->second; 3029 } 3030 3031 // Merge or overload the declaration with an existing declaration of 3032 // the same name, if appropriate. 3033 if (PrevDecl) { 3034 // Determine whether NewFD is an overload of PrevDecl or 3035 // a declaration that requires merging. If it's an overload, 3036 // there's no more work to do here; we'll just add the new 3037 // function to the scope. 3038 OverloadedFunctionDecl::function_iterator MatchedDecl; 3039 3040 if (!getLangOptions().CPlusPlus && 3041 AllowOverloadingOfFunction(PrevDecl, Context)) { 3042 OverloadableAttrRequired = true; 3043 3044 // Functions marked "overloadable" must have a prototype (that 3045 // we can't get through declaration merging). 3046 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3047 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3048 << NewFD; 3049 Redeclaration = true; 3050 3051 // Turn this into a variadic function with no parameters. 3052 QualType R = Context.getFunctionType( 3053 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3054 0, 0, true, 0); 3055 NewFD->setType(R); 3056 return NewFD->setInvalidDecl(); 3057 } 3058 } 3059 3060 if (PrevDecl && 3061 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3062 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3063 Redeclaration = true; 3064 Decl *OldDecl = PrevDecl; 3065 3066 // If PrevDecl was an overloaded function, extract the 3067 // FunctionDecl that matched. 3068 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3069 OldDecl = *MatchedDecl; 3070 3071 // NewFD and OldDecl represent declarations that need to be 3072 // merged. 3073 if (MergeFunctionDecl(NewFD, OldDecl)) 3074 return NewFD->setInvalidDecl(); 3075 3076 if (FunctionTemplateDecl *OldTemplateDecl 3077 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3078 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3079 FunctionTemplateDecl *NewTemplateDecl 3080 = NewFD->getDescribedFunctionTemplate(); 3081 assert(NewTemplateDecl && "Template/non-template mismatch"); 3082 if (CXXMethodDecl *Method 3083 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3084 Method->setAccess(OldTemplateDecl->getAccess()); 3085 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3086 } 3087 3088 // If this is an explicit specialization of a member that is a function 3089 // template, mark it as a member specialization. 3090 if (IsExplicitSpecialization && 3091 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3092 NewTemplateDecl->setMemberSpecialization(); 3093 assert(OldTemplateDecl->isMemberSpecialization()); 3094 } 3095 } else { 3096 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3097 NewFD->setAccess(OldDecl->getAccess()); 3098 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3099 } 3100 } 3101 } 3102 3103 // Semantic checking for this function declaration (in isolation). 3104 if (getLangOptions().CPlusPlus) { 3105 // C++-specific checks. 3106 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3107 CheckConstructor(Constructor); 3108 } else if (isa<CXXDestructorDecl>(NewFD)) { 3109 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3110 QualType ClassType = Context.getTypeDeclType(Record); 3111 if (!ClassType->isDependentType()) { 3112 DeclarationName Name 3113 = Context.DeclarationNames.getCXXDestructorName( 3114 Context.getCanonicalType(ClassType)); 3115 if (NewFD->getDeclName() != Name) { 3116 Diag(NewFD->getLocation(), diag::err_destructor_name); 3117 return NewFD->setInvalidDecl(); 3118 } 3119 } 3120 Record->setUserDeclaredDestructor(true); 3121 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3122 // user-defined destructor. 3123 Record->setPOD(false); 3124 3125 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3126 // declared destructor. 3127 // FIXME: C++0x: don't do this for "= default" destructors 3128 Record->setHasTrivialDestructor(false); 3129 } else if (CXXConversionDecl *Conversion 3130 = dyn_cast<CXXConversionDecl>(NewFD)) 3131 ActOnConversionDeclarator(Conversion); 3132 3133 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3134 if (NewFD->isOverloadedOperator() && 3135 CheckOverloadedOperatorDeclaration(NewFD)) 3136 return NewFD->setInvalidDecl(); 3137 3138 // In C++, check default arguments now that we have merged decls. Unless 3139 // the lexical context is the class, because in this case this is done 3140 // during delayed parsing anyway. 3141 if (!CurContext->isRecord()) 3142 CheckCXXDefaultArguments(NewFD); 3143 } 3144} 3145 3146void Sema::CheckMain(FunctionDecl* FD) { 3147 // C++ [basic.start.main]p3: A program that declares main to be inline 3148 // or static is ill-formed. 3149 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3150 // shall not appear in a declaration of main. 3151 // static main is not an error under C99, but we should warn about it. 3152 bool isInline = FD->isInlineSpecified(); 3153 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3154 if (isInline || isStatic) { 3155 unsigned diagID = diag::warn_unusual_main_decl; 3156 if (isInline || getLangOptions().CPlusPlus) 3157 diagID = diag::err_unusual_main_decl; 3158 3159 int which = isStatic + (isInline << 1) - 1; 3160 Diag(FD->getLocation(), diagID) << which; 3161 } 3162 3163 QualType T = FD->getType(); 3164 assert(T->isFunctionType() && "function decl is not of function type"); 3165 const FunctionType* FT = T->getAs<FunctionType>(); 3166 3167 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3168 // TODO: add a replacement fixit to turn the return type into 'int'. 3169 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3170 FD->setInvalidDecl(true); 3171 } 3172 3173 // Treat protoless main() as nullary. 3174 if (isa<FunctionNoProtoType>(FT)) return; 3175 3176 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3177 unsigned nparams = FTP->getNumArgs(); 3178 assert(FD->getNumParams() == nparams); 3179 3180 if (nparams > 3) { 3181 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3182 FD->setInvalidDecl(true); 3183 nparams = 3; 3184 } 3185 3186 // FIXME: a lot of the following diagnostics would be improved 3187 // if we had some location information about types. 3188 3189 QualType CharPP = 3190 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3191 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3192 3193 for (unsigned i = 0; i < nparams; ++i) { 3194 QualType AT = FTP->getArgType(i); 3195 3196 bool mismatch = true; 3197 3198 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3199 mismatch = false; 3200 else if (Expected[i] == CharPP) { 3201 // As an extension, the following forms are okay: 3202 // char const ** 3203 // char const * const * 3204 // char * const * 3205 3206 QualifierCollector qs; 3207 const PointerType* PT; 3208 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3209 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3210 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3211 qs.removeConst(); 3212 mismatch = !qs.empty(); 3213 } 3214 } 3215 3216 if (mismatch) { 3217 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3218 // TODO: suggest replacing given type with expected type 3219 FD->setInvalidDecl(true); 3220 } 3221 } 3222 3223 if (nparams == 1 && !FD->isInvalidDecl()) { 3224 Diag(FD->getLocation(), diag::warn_main_one_arg); 3225 } 3226} 3227 3228bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3229 // FIXME: Need strict checking. In C89, we need to check for 3230 // any assignment, increment, decrement, function-calls, or 3231 // commas outside of a sizeof. In C99, it's the same list, 3232 // except that the aforementioned are allowed in unevaluated 3233 // expressions. Everything else falls under the 3234 // "may accept other forms of constant expressions" exception. 3235 // (We never end up here for C++, so the constant expression 3236 // rules there don't matter.) 3237 if (Init->isConstantInitializer(Context)) 3238 return false; 3239 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3240 << Init->getSourceRange(); 3241 return true; 3242} 3243 3244void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3245 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3246} 3247 3248/// AddInitializerToDecl - Adds the initializer Init to the 3249/// declaration dcl. If DirectInit is true, this is C++ direct 3250/// initialization rather than copy initialization. 3251void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3252 Decl *RealDecl = dcl.getAs<Decl>(); 3253 // If there is no declaration, there was an error parsing it. Just ignore 3254 // the initializer. 3255 if (RealDecl == 0) 3256 return; 3257 3258 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3259 // With declarators parsed the way they are, the parser cannot 3260 // distinguish between a normal initializer and a pure-specifier. 3261 // Thus this grotesque test. 3262 IntegerLiteral *IL; 3263 Expr *Init = static_cast<Expr *>(init.get()); 3264 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3265 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3266 if (Method->isVirtualAsWritten()) { 3267 Method->setPure(); 3268 3269 // A class is abstract if at least one function is pure virtual. 3270 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3271 } else if (!Method->isInvalidDecl()) { 3272 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3273 << Method->getDeclName() << Init->getSourceRange(); 3274 Method->setInvalidDecl(); 3275 } 3276 } else { 3277 Diag(Method->getLocation(), diag::err_member_function_initialization) 3278 << Method->getDeclName() << Init->getSourceRange(); 3279 Method->setInvalidDecl(); 3280 } 3281 return; 3282 } 3283 3284 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3285 if (!VDecl) { 3286 if (getLangOptions().CPlusPlus && 3287 RealDecl->getLexicalDeclContext()->isRecord() && 3288 isa<NamedDecl>(RealDecl)) 3289 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3290 << cast<NamedDecl>(RealDecl)->getDeclName(); 3291 else 3292 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3293 RealDecl->setInvalidDecl(); 3294 return; 3295 } 3296 3297 // A definition must end up with a complete type, which means it must be 3298 // complete with the restriction that an array type might be completed by the 3299 // initializer; note that later code assumes this restriction. 3300 QualType BaseDeclType = VDecl->getType(); 3301 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3302 BaseDeclType = Array->getElementType(); 3303 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3304 diag::err_typecheck_decl_incomplete_type)) { 3305 RealDecl->setInvalidDecl(); 3306 return; 3307 } 3308 3309 const VarDecl *Def = 0; 3310 if (VDecl->getDefinition(Def)) { 3311 Diag(VDecl->getLocation(), diag::err_redefinition) 3312 << VDecl->getDeclName(); 3313 Diag(Def->getLocation(), diag::note_previous_definition); 3314 VDecl->setInvalidDecl(); 3315 return; 3316 } 3317 3318 // Take ownership of the expression, now that we're sure we have somewhere 3319 // to put it. 3320 Expr *Init = init.takeAs<Expr>(); 3321 assert(Init && "missing initializer"); 3322 3323 // Get the decls type and save a reference for later, since 3324 // CheckInitializerTypes may change it. 3325 QualType DclT = VDecl->getType(), SavT = DclT; 3326 if (VDecl->isBlockVarDecl()) { 3327 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3328 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3329 VDecl->setInvalidDecl(); 3330 } else if (!VDecl->isInvalidDecl()) { 3331 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3332 VDecl->getDeclName(), DirectInit)) 3333 VDecl->setInvalidDecl(); 3334 3335 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3336 // Don't check invalid declarations to avoid emitting useless diagnostics. 3337 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3338 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3339 CheckForConstantInitializer(Init, DclT); 3340 } 3341 } 3342 } else if (VDecl->isStaticDataMember() && 3343 VDecl->getLexicalDeclContext()->isRecord()) { 3344 // This is an in-class initialization for a static data member, e.g., 3345 // 3346 // struct S { 3347 // static const int value = 17; 3348 // }; 3349 3350 // Attach the initializer 3351 VDecl->setInit(Context, Init); 3352 3353 // C++ [class.mem]p4: 3354 // A member-declarator can contain a constant-initializer only 3355 // if it declares a static member (9.4) of const integral or 3356 // const enumeration type, see 9.4.2. 3357 QualType T = VDecl->getType(); 3358 if (!T->isDependentType() && 3359 (!Context.getCanonicalType(T).isConstQualified() || 3360 !T->isIntegralType())) { 3361 Diag(VDecl->getLocation(), diag::err_member_initialization) 3362 << VDecl->getDeclName() << Init->getSourceRange(); 3363 VDecl->setInvalidDecl(); 3364 } else { 3365 // C++ [class.static.data]p4: 3366 // If a static data member is of const integral or const 3367 // enumeration type, its declaration in the class definition 3368 // can specify a constant-initializer which shall be an 3369 // integral constant expression (5.19). 3370 if (!Init->isTypeDependent() && 3371 !Init->getType()->isIntegralType()) { 3372 // We have a non-dependent, non-integral or enumeration type. 3373 Diag(Init->getSourceRange().getBegin(), 3374 diag::err_in_class_initializer_non_integral_type) 3375 << Init->getType() << Init->getSourceRange(); 3376 VDecl->setInvalidDecl(); 3377 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3378 // Check whether the expression is a constant expression. 3379 llvm::APSInt Value; 3380 SourceLocation Loc; 3381 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3382 Diag(Loc, diag::err_in_class_initializer_non_constant) 3383 << Init->getSourceRange(); 3384 VDecl->setInvalidDecl(); 3385 } else if (!VDecl->getType()->isDependentType()) 3386 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3387 } 3388 } 3389 } else if (VDecl->isFileVarDecl()) { 3390 if (VDecl->getStorageClass() == VarDecl::Extern) 3391 Diag(VDecl->getLocation(), diag::warn_extern_init); 3392 if (!VDecl->isInvalidDecl()) 3393 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3394 VDecl->getDeclName(), DirectInit)) 3395 VDecl->setInvalidDecl(); 3396 3397 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3398 // Don't check invalid declarations to avoid emitting useless diagnostics. 3399 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3400 // C99 6.7.8p4. All file scoped initializers need to be constant. 3401 CheckForConstantInitializer(Init, DclT); 3402 } 3403 } 3404 // If the type changed, it means we had an incomplete type that was 3405 // completed by the initializer. For example: 3406 // int ary[] = { 1, 3, 5 }; 3407 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3408 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3409 VDecl->setType(DclT); 3410 Init->setType(DclT); 3411 } 3412 3413 Init = MaybeCreateCXXExprWithTemporaries(Init, 3414 /*ShouldDestroyTemporaries=*/true); 3415 // Attach the initializer to the decl. 3416 VDecl->setInit(Context, Init); 3417 3418 // If the previous declaration of VDecl was a tentative definition, 3419 // remove it from the set of tentative definitions. 3420 if (VDecl->getPreviousDeclaration() && 3421 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3422 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3423 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3424 } 3425 3426 return; 3427} 3428 3429void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3430 bool TypeContainsUndeducedAuto) { 3431 Decl *RealDecl = dcl.getAs<Decl>(); 3432 3433 // If there is no declaration, there was an error parsing it. Just ignore it. 3434 if (RealDecl == 0) 3435 return; 3436 3437 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3438 QualType Type = Var->getType(); 3439 3440 // Record tentative definitions. 3441 if (Var->isTentativeDefinition(Context)) { 3442 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3443 InsertPair = 3444 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3445 3446 // Keep the latest definition in the map. If we see 'int i; int i;' we 3447 // want the second one in the map. 3448 InsertPair.first->second = Var; 3449 3450 // However, for the list, we don't care about the order, just make sure 3451 // that there are no dupes for a given declaration name. 3452 if (InsertPair.second) 3453 TentativeDefinitionList.push_back(Var->getDeclName()); 3454 } 3455 3456 // C++ [dcl.init.ref]p3: 3457 // The initializer can be omitted for a reference only in a 3458 // parameter declaration (8.3.5), in the declaration of a 3459 // function return type, in the declaration of a class member 3460 // within its class declaration (9.2), and where the extern 3461 // specifier is explicitly used. 3462 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3463 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3464 << Var->getDeclName() 3465 << SourceRange(Var->getLocation(), Var->getLocation()); 3466 Var->setInvalidDecl(); 3467 return; 3468 } 3469 3470 // C++0x [dcl.spec.auto]p3 3471 if (TypeContainsUndeducedAuto) { 3472 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3473 << Var->getDeclName() << Type; 3474 Var->setInvalidDecl(); 3475 return; 3476 } 3477 3478 // An array without size is an incomplete type, and there are no special 3479 // rules in C++ to make such a definition acceptable. 3480 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3481 !Var->hasExternalStorage()) { 3482 Diag(Var->getLocation(), 3483 diag::err_typecheck_incomplete_array_needs_initializer); 3484 Var->setInvalidDecl(); 3485 return; 3486 } 3487 3488 // C++ [temp.expl.spec]p15: 3489 // An explicit specialization of a static data member of a template is a 3490 // definition if the declaration includes an initializer; otherwise, it 3491 // is a declaration. 3492 if (Var->isStaticDataMember() && 3493 Var->getInstantiatedFromStaticDataMember() && 3494 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3495 return; 3496 3497 // C++ [dcl.init]p9: 3498 // If no initializer is specified for an object, and the object 3499 // is of (possibly cv-qualified) non-POD class type (or array 3500 // thereof), the object shall be default-initialized; if the 3501 // object is of const-qualified type, the underlying class type 3502 // shall have a user-declared default constructor. 3503 // 3504 // FIXME: Diagnose the "user-declared default constructor" bit. 3505 if (getLangOptions().CPlusPlus) { 3506 QualType InitType = Type; 3507 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3508 InitType = Context.getBaseElementType(Array); 3509 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3510 InitType->isRecordType() && !InitType->isDependentType()) { 3511 if (!RequireCompleteType(Var->getLocation(), InitType, 3512 diag::err_invalid_incomplete_type_use)) { 3513 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3514 3515 CXXConstructorDecl *Constructor 3516 = PerformInitializationByConstructor(InitType, 3517 MultiExprArg(*this, 0, 0), 3518 Var->getLocation(), 3519 SourceRange(Var->getLocation(), 3520 Var->getLocation()), 3521 Var->getDeclName(), 3522 IK_Default, 3523 ConstructorArgs); 3524 3525 // FIXME: Location info for the variable initialization? 3526 if (!Constructor) 3527 Var->setInvalidDecl(); 3528 else { 3529 // FIXME: Cope with initialization of arrays 3530 if (!Constructor->isTrivial() && 3531 InitializeVarWithConstructor(Var, Constructor, 3532 move_arg(ConstructorArgs))) 3533 Var->setInvalidDecl(); 3534 3535 FinalizeVarWithDestructor(Var, InitType); 3536 } 3537 } else { 3538 Var->setInvalidDecl(); 3539 } 3540 } 3541 } 3542 3543#if 0 3544 // FIXME: Temporarily disabled because we are not properly parsing 3545 // linkage specifications on declarations, e.g., 3546 // 3547 // extern "C" const CGPoint CGPointerZero; 3548 // 3549 // C++ [dcl.init]p9: 3550 // 3551 // If no initializer is specified for an object, and the 3552 // object is of (possibly cv-qualified) non-POD class type (or 3553 // array thereof), the object shall be default-initialized; if 3554 // the object is of const-qualified type, the underlying class 3555 // type shall have a user-declared default 3556 // constructor. Otherwise, if no initializer is specified for 3557 // an object, the object and its subobjects, if any, have an 3558 // indeterminate initial value; if the object or any of its 3559 // subobjects are of const-qualified type, the program is 3560 // ill-formed. 3561 // 3562 // This isn't technically an error in C, so we don't diagnose it. 3563 // 3564 // FIXME: Actually perform the POD/user-defined default 3565 // constructor check. 3566 if (getLangOptions().CPlusPlus && 3567 Context.getCanonicalType(Type).isConstQualified() && 3568 !Var->hasExternalStorage()) 3569 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3570 << Var->getName() 3571 << SourceRange(Var->getLocation(), Var->getLocation()); 3572#endif 3573 } 3574} 3575 3576Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3577 DeclPtrTy *Group, 3578 unsigned NumDecls) { 3579 llvm::SmallVector<Decl*, 8> Decls; 3580 3581 if (DS.isTypeSpecOwned()) 3582 Decls.push_back((Decl*)DS.getTypeRep()); 3583 3584 for (unsigned i = 0; i != NumDecls; ++i) 3585 if (Decl *D = Group[i].getAs<Decl>()) 3586 Decls.push_back(D); 3587 3588 // Perform semantic analysis that depends on having fully processed both 3589 // the declarator and initializer. 3590 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3591 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3592 if (!IDecl) 3593 continue; 3594 QualType T = IDecl->getType(); 3595 3596 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3597 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3598 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3599 if (T->isDependentType()) { 3600 // If T is dependent, we should not require a complete type. 3601 // (RequireCompleteType shouldn't be called with dependent types.) 3602 // But we still can at least check if we've got an array of unspecified 3603 // size without an initializer. 3604 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3605 !IDecl->getInit()) { 3606 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3607 << T; 3608 IDecl->setInvalidDecl(); 3609 } 3610 } else if (!IDecl->isInvalidDecl()) { 3611 // If T is an incomplete array type with an initializer list that is 3612 // dependent on something, its size has not been fixed. We could attempt 3613 // to fix the size for such arrays, but we would still have to check 3614 // here for initializers containing a C++0x vararg expansion, e.g. 3615 // template <typename... Args> void f(Args... args) { 3616 // int vals[] = { args }; 3617 // } 3618 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3619 Expr *Init = IDecl->getInit(); 3620 if (IAT && Init && 3621 (Init->isTypeDependent() || Init->isValueDependent())) { 3622 // Check that the member type of the array is complete, at least. 3623 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3624 diag::err_typecheck_decl_incomplete_type)) 3625 IDecl->setInvalidDecl(); 3626 } else if (RequireCompleteType(IDecl->getLocation(), T, 3627 diag::err_typecheck_decl_incomplete_type)) 3628 IDecl->setInvalidDecl(); 3629 } 3630 } 3631 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3632 // object that has file scope without an initializer, and without a 3633 // storage-class specifier or with the storage-class specifier "static", 3634 // constitutes a tentative definition. Note: A tentative definition with 3635 // external linkage is valid (C99 6.2.2p5). 3636 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3637 if (const IncompleteArrayType *ArrayT 3638 = Context.getAsIncompleteArrayType(T)) { 3639 if (RequireCompleteType(IDecl->getLocation(), 3640 ArrayT->getElementType(), 3641 diag::err_illegal_decl_array_incomplete_type)) 3642 IDecl->setInvalidDecl(); 3643 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3644 // C99 6.9.2p3: If the declaration of an identifier for an object is 3645 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3646 // declared type shall not be an incomplete type. 3647 // NOTE: code such as the following 3648 // static struct s; 3649 // struct s { int a; }; 3650 // is accepted by gcc. Hence here we issue a warning instead of 3651 // an error and we do not invalidate the static declaration. 3652 // NOTE: to avoid multiple warnings, only check the first declaration. 3653 if (IDecl->getPreviousDeclaration() == 0) 3654 RequireCompleteType(IDecl->getLocation(), T, 3655 diag::ext_typecheck_decl_incomplete_type); 3656 } 3657 } 3658 } 3659 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3660 Decls.data(), Decls.size())); 3661} 3662 3663 3664/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3665/// to introduce parameters into function prototype scope. 3666Sema::DeclPtrTy 3667Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3668 const DeclSpec &DS = D.getDeclSpec(); 3669 3670 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3671 VarDecl::StorageClass StorageClass = VarDecl::None; 3672 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3673 StorageClass = VarDecl::Register; 3674 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3675 Diag(DS.getStorageClassSpecLoc(), 3676 diag::err_invalid_storage_class_in_func_decl); 3677 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3678 } 3679 3680 if (D.getDeclSpec().isThreadSpecified()) 3681 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3682 3683 DiagnoseFunctionSpecifiers(D); 3684 3685 // Check that there are no default arguments inside the type of this 3686 // parameter (C++ only). 3687 if (getLangOptions().CPlusPlus) 3688 CheckExtraCXXDefaultArguments(D); 3689 3690 DeclaratorInfo *DInfo = 0; 3691 TagDecl *OwnedDecl = 0; 3692 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3693 3694 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3695 // C++ [dcl.fct]p6: 3696 // Types shall not be defined in return or parameter types. 3697 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3698 << Context.getTypeDeclType(OwnedDecl); 3699 } 3700 3701 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3702 // Can this happen for params? We already checked that they don't conflict 3703 // among each other. Here they can only shadow globals, which is ok. 3704 IdentifierInfo *II = D.getIdentifier(); 3705 if (II) { 3706 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3707 if (PrevDecl->isTemplateParameter()) { 3708 // Maybe we will complain about the shadowed template parameter. 3709 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3710 // Just pretend that we didn't see the previous declaration. 3711 PrevDecl = 0; 3712 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3713 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3714 3715 // Recover by removing the name 3716 II = 0; 3717 D.SetIdentifier(0, D.getIdentifierLoc()); 3718 } 3719 } 3720 } 3721 3722 // Parameters can not be abstract class types. 3723 // For record types, this is done by the AbstractClassUsageDiagnoser once 3724 // the class has been completely parsed. 3725 if (!CurContext->isRecord() && 3726 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3727 diag::err_abstract_type_in_decl, 3728 AbstractParamType)) 3729 D.setInvalidType(true); 3730 3731 QualType T = adjustParameterType(parmDeclType); 3732 3733 ParmVarDecl *New 3734 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3735 T, DInfo, StorageClass, 0); 3736 3737 if (D.isInvalidType()) 3738 New->setInvalidDecl(); 3739 3740 // Parameter declarators cannot be interface types. All ObjC objects are 3741 // passed by reference. 3742 if (T->isObjCInterfaceType()) { 3743 Diag(D.getIdentifierLoc(), 3744 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3745 New->setInvalidDecl(); 3746 } 3747 3748 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3749 if (D.getCXXScopeSpec().isSet()) { 3750 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3751 << D.getCXXScopeSpec().getRange(); 3752 New->setInvalidDecl(); 3753 } 3754 3755 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3756 // duration shall not be qualified by an address-space qualifier." 3757 // Since all parameters have automatic store duration, they can not have 3758 // an address space. 3759 if (T.getAddressSpace() != 0) { 3760 Diag(D.getIdentifierLoc(), 3761 diag::err_arg_with_address_space); 3762 New->setInvalidDecl(); 3763 } 3764 3765 3766 // Add the parameter declaration into this scope. 3767 S->AddDecl(DeclPtrTy::make(New)); 3768 if (II) 3769 IdResolver.AddDecl(New); 3770 3771 ProcessDeclAttributes(S, New, D); 3772 3773 if (New->hasAttr<BlocksAttr>()) { 3774 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3775 } 3776 return DeclPtrTy::make(New); 3777} 3778 3779void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3780 SourceLocation LocAfterDecls) { 3781 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3782 "Not a function declarator!"); 3783 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3784 3785 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3786 // for a K&R function. 3787 if (!FTI.hasPrototype) { 3788 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3789 --i; 3790 if (FTI.ArgInfo[i].Param == 0) { 3791 llvm::SmallString<256> Code; 3792 llvm::raw_svector_ostream(Code) << " int " 3793 << FTI.ArgInfo[i].Ident->getName() 3794 << ";\n"; 3795 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3796 << FTI.ArgInfo[i].Ident 3797 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3798 3799 // Implicitly declare the argument as type 'int' for lack of a better 3800 // type. 3801 DeclSpec DS; 3802 const char* PrevSpec; // unused 3803 unsigned DiagID; // unused 3804 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3805 PrevSpec, DiagID); 3806 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3807 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3808 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3809 } 3810 } 3811 } 3812} 3813 3814Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3815 Declarator &D) { 3816 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3817 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3818 "Not a function declarator!"); 3819 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3820 3821 if (FTI.hasPrototype) { 3822 // FIXME: Diagnose arguments without names in C. 3823 } 3824 3825 Scope *ParentScope = FnBodyScope->getParent(); 3826 3827 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3828 MultiTemplateParamsArg(*this), 3829 /*IsFunctionDefinition=*/true); 3830 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3831} 3832 3833Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3834 // Clear the last template instantiation error context. 3835 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 3836 3837 if (!D) 3838 return D; 3839 FunctionDecl *FD = 0; 3840 3841 if (FunctionTemplateDecl *FunTmpl 3842 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3843 FD = FunTmpl->getTemplatedDecl(); 3844 else 3845 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3846 3847 CurFunctionNeedsScopeChecking = false; 3848 3849 // See if this is a redefinition. 3850 const FunctionDecl *Definition; 3851 if (FD->getBody(Definition)) { 3852 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3853 Diag(Definition->getLocation(), diag::note_previous_definition); 3854 } 3855 3856 // Builtin functions cannot be defined. 3857 if (unsigned BuiltinID = FD->getBuiltinID()) { 3858 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3859 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3860 FD->setInvalidDecl(); 3861 } 3862 } 3863 3864 // The return type of a function definition must be complete 3865 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3866 QualType ResultType = FD->getResultType(); 3867 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3868 !FD->isInvalidDecl() && 3869 RequireCompleteType(FD->getLocation(), ResultType, 3870 diag::err_func_def_incomplete_result)) 3871 FD->setInvalidDecl(); 3872 3873 // GNU warning -Wmissing-prototypes: 3874 // Warn if a global function is defined without a previous 3875 // prototype declaration. This warning is issued even if the 3876 // definition itself provides a prototype. The aim is to detect 3877 // global functions that fail to be declared in header files. 3878 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3879 !FD->isMain()) { 3880 bool MissingPrototype = true; 3881 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3882 Prev; Prev = Prev->getPreviousDeclaration()) { 3883 // Ignore any declarations that occur in function or method 3884 // scope, because they aren't visible from the header. 3885 if (Prev->getDeclContext()->isFunctionOrMethod()) 3886 continue; 3887 3888 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3889 break; 3890 } 3891 3892 if (MissingPrototype) 3893 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3894 } 3895 3896 if (FnBodyScope) 3897 PushDeclContext(FnBodyScope, FD); 3898 3899 // Check the validity of our function parameters 3900 CheckParmsForFunctionDef(FD); 3901 3902 // Introduce our parameters into the function scope 3903 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3904 ParmVarDecl *Param = FD->getParamDecl(p); 3905 Param->setOwningFunction(FD); 3906 3907 // If this has an identifier, add it to the scope stack. 3908 if (Param->getIdentifier() && FnBodyScope) 3909 PushOnScopeChains(Param, FnBodyScope); 3910 } 3911 3912 // Checking attributes of current function definition 3913 // dllimport attribute. 3914 if (FD->getAttr<DLLImportAttr>() && 3915 (!FD->getAttr<DLLExportAttr>())) { 3916 // dllimport attribute cannot be applied to definition. 3917 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3918 Diag(FD->getLocation(), 3919 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3920 << "dllimport"; 3921 FD->setInvalidDecl(); 3922 return DeclPtrTy::make(FD); 3923 } else { 3924 // If a symbol previously declared dllimport is later defined, the 3925 // attribute is ignored in subsequent references, and a warning is 3926 // emitted. 3927 Diag(FD->getLocation(), 3928 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3929 << FD->getNameAsCString() << "dllimport"; 3930 } 3931 } 3932 return DeclPtrTy::make(FD); 3933} 3934 3935Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3936 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3937} 3938 3939Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3940 bool IsInstantiation) { 3941 Decl *dcl = D.getAs<Decl>(); 3942 Stmt *Body = BodyArg.takeAs<Stmt>(); 3943 3944 FunctionDecl *FD = 0; 3945 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3946 if (FunTmpl) 3947 FD = FunTmpl->getTemplatedDecl(); 3948 else 3949 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3950 3951 if (FD) { 3952 FD->setBody(Body); 3953 if (FD->isMain()) 3954 // C and C++ allow for main to automagically return 0. 3955 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3956 FD->setHasImplicitReturnZero(true); 3957 else 3958 CheckFallThroughForFunctionDef(FD, Body); 3959 3960 if (!FD->isInvalidDecl()) 3961 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3962 3963 // C++ [basic.def.odr]p2: 3964 // [...] A virtual member function is used if it is not pure. [...] 3965 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3966 if (Method->isVirtual() && !Method->isPure()) 3967 MarkDeclarationReferenced(Method->getLocation(), Method); 3968 3969 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3970 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3971 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3972 MD->setBody(Body); 3973 CheckFallThroughForFunctionDef(MD, Body); 3974 MD->setEndLoc(Body->getLocEnd()); 3975 3976 if (!MD->isInvalidDecl()) 3977 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3978 } else { 3979 Body->Destroy(Context); 3980 return DeclPtrTy(); 3981 } 3982 if (!IsInstantiation) 3983 PopDeclContext(); 3984 3985 // Verify and clean out per-function state. 3986 3987 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3988 3989 // Check goto/label use. 3990 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3991 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3992 LabelStmt *L = I->second; 3993 3994 // Verify that we have no forward references left. If so, there was a goto 3995 // or address of a label taken, but no definition of it. Label fwd 3996 // definitions are indicated with a null substmt. 3997 if (L->getSubStmt() != 0) 3998 continue; 3999 4000 // Emit error. 4001 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4002 4003 // At this point, we have gotos that use the bogus label. Stitch it into 4004 // the function body so that they aren't leaked and that the AST is well 4005 // formed. 4006 if (Body == 0) { 4007 // The whole function wasn't parsed correctly, just delete this. 4008 L->Destroy(Context); 4009 continue; 4010 } 4011 4012 // Otherwise, the body is valid: we want to stitch the label decl into the 4013 // function somewhere so that it is properly owned and so that the goto 4014 // has a valid target. Do this by creating a new compound stmt with the 4015 // label in it. 4016 4017 // Give the label a sub-statement. 4018 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4019 4020 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4021 cast<CXXTryStmt>(Body)->getTryBlock() : 4022 cast<CompoundStmt>(Body); 4023 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4024 Elements.push_back(L); 4025 Compound->setStmts(Context, &Elements[0], Elements.size()); 4026 } 4027 FunctionLabelMap.clear(); 4028 4029 if (!Body) return D; 4030 4031 // Verify that that gotos and switch cases don't jump into scopes illegally. 4032 if (CurFunctionNeedsScopeChecking) 4033 DiagnoseInvalidJumps(Body); 4034 4035 // C++ constructors that have function-try-blocks can't have return 4036 // statements in the handlers of that block. (C++ [except.handle]p14) 4037 // Verify this. 4038 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4039 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4040 4041 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4042 computeBaseOrMembersToDestroy(Destructor); 4043 4044 // If any errors have occurred, clear out any temporaries that may have 4045 // been leftover. This ensures that these temporaries won't be picked up for 4046 // deletion in some later function. 4047 if (PP.getDiagnostics().hasErrorOccurred()) 4048 ExprTemporaries.clear(); 4049 4050 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4051 return D; 4052} 4053 4054/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4055/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4056NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4057 IdentifierInfo &II, Scope *S) { 4058 // Before we produce a declaration for an implicitly defined 4059 // function, see whether there was a locally-scoped declaration of 4060 // this name as a function or variable. If so, use that 4061 // (non-visible) declaration, and complain about it. 4062 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4063 = LocallyScopedExternalDecls.find(&II); 4064 if (Pos != LocallyScopedExternalDecls.end()) { 4065 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4066 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4067 return Pos->second; 4068 } 4069 4070 // Extension in C99. Legal in C90, but warn about it. 4071 if (II.getName().startswith("__builtin_")) 4072 Diag(Loc, diag::warn_builtin_unknown) << &II; 4073 else if (getLangOptions().C99) 4074 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4075 else 4076 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4077 4078 // Set a Declarator for the implicit definition: int foo(); 4079 const char *Dummy; 4080 DeclSpec DS; 4081 unsigned DiagID; 4082 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4083 Error = Error; // Silence warning. 4084 assert(!Error && "Error setting up implicit decl!"); 4085 Declarator D(DS, Declarator::BlockContext); 4086 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4087 0, 0, false, SourceLocation(), 4088 false, 0,0,0, Loc, Loc, D), 4089 SourceLocation()); 4090 D.SetIdentifier(&II, Loc); 4091 4092 // Insert this function into translation-unit scope. 4093 4094 DeclContext *PrevDC = CurContext; 4095 CurContext = Context.getTranslationUnitDecl(); 4096 4097 FunctionDecl *FD = 4098 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4099 FD->setImplicit(); 4100 4101 CurContext = PrevDC; 4102 4103 AddKnownFunctionAttributes(FD); 4104 4105 return FD; 4106} 4107 4108/// \brief Adds any function attributes that we know a priori based on 4109/// the declaration of this function. 4110/// 4111/// These attributes can apply both to implicitly-declared builtins 4112/// (like __builtin___printf_chk) or to library-declared functions 4113/// like NSLog or printf. 4114void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4115 if (FD->isInvalidDecl()) 4116 return; 4117 4118 // If this is a built-in function, map its builtin attributes to 4119 // actual attributes. 4120 if (unsigned BuiltinID = FD->getBuiltinID()) { 4121 // Handle printf-formatting attributes. 4122 unsigned FormatIdx; 4123 bool HasVAListArg; 4124 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4125 if (!FD->getAttr<FormatAttr>()) 4126 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4127 HasVAListArg ? 0 : FormatIdx + 2)); 4128 } 4129 4130 // Mark const if we don't care about errno and that is the only 4131 // thing preventing the function from being const. This allows 4132 // IRgen to use LLVM intrinsics for such functions. 4133 if (!getLangOptions().MathErrno && 4134 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4135 if (!FD->getAttr<ConstAttr>()) 4136 FD->addAttr(::new (Context) ConstAttr()); 4137 } 4138 4139 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4140 FD->addAttr(::new (Context) NoReturnAttr()); 4141 } 4142 4143 IdentifierInfo *Name = FD->getIdentifier(); 4144 if (!Name) 4145 return; 4146 if ((!getLangOptions().CPlusPlus && 4147 FD->getDeclContext()->isTranslationUnit()) || 4148 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4149 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4150 LinkageSpecDecl::lang_c)) { 4151 // Okay: this could be a libc/libm/Objective-C function we know 4152 // about. 4153 } else 4154 return; 4155 4156 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4157 // FIXME: NSLog and NSLogv should be target specific 4158 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4159 // FIXME: We known better than our headers. 4160 const_cast<FormatAttr *>(Format)->setType("printf"); 4161 } else 4162 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4163 Name->isStr("NSLogv") ? 0 : 2)); 4164 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4165 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4166 // target-specific builtins, perhaps? 4167 if (!FD->getAttr<FormatAttr>()) 4168 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4169 Name->isStr("vasprintf") ? 0 : 3)); 4170 } 4171} 4172 4173TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4174 DeclaratorInfo *DInfo) { 4175 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4176 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4177 4178 if (!DInfo) { 4179 assert(D.isInvalidType() && "no declarator info for valid type"); 4180 DInfo = Context.getTrivialDeclaratorInfo(T); 4181 } 4182 4183 // Scope manipulation handled by caller. 4184 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4185 D.getIdentifierLoc(), 4186 D.getIdentifier(), 4187 DInfo); 4188 4189 if (const TagType *TT = T->getAs<TagType>()) { 4190 TagDecl *TD = TT->getDecl(); 4191 4192 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4193 // keep track of the TypedefDecl. 4194 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4195 TD->setTypedefForAnonDecl(NewTD); 4196 } 4197 4198 if (D.isInvalidType()) 4199 NewTD->setInvalidDecl(); 4200 return NewTD; 4201} 4202 4203 4204/// \brief Determine whether a tag with a given kind is acceptable 4205/// as a redeclaration of the given tag declaration. 4206/// 4207/// \returns true if the new tag kind is acceptable, false otherwise. 4208bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4209 TagDecl::TagKind NewTag, 4210 SourceLocation NewTagLoc, 4211 const IdentifierInfo &Name) { 4212 // C++ [dcl.type.elab]p3: 4213 // The class-key or enum keyword present in the 4214 // elaborated-type-specifier shall agree in kind with the 4215 // declaration to which the name in theelaborated-type-specifier 4216 // refers. This rule also applies to the form of 4217 // elaborated-type-specifier that declares a class-name or 4218 // friend class since it can be construed as referring to the 4219 // definition of the class. Thus, in any 4220 // elaborated-type-specifier, the enum keyword shall be used to 4221 // refer to an enumeration (7.2), the union class-keyshall be 4222 // used to refer to a union (clause 9), and either the class or 4223 // struct class-key shall be used to refer to a class (clause 9) 4224 // declared using the class or struct class-key. 4225 TagDecl::TagKind OldTag = Previous->getTagKind(); 4226 if (OldTag == NewTag) 4227 return true; 4228 4229 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4230 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4231 // Warn about the struct/class tag mismatch. 4232 bool isTemplate = false; 4233 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4234 isTemplate = Record->getDescribedClassTemplate(); 4235 4236 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4237 << (NewTag == TagDecl::TK_class) 4238 << isTemplate << &Name 4239 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4240 OldTag == TagDecl::TK_class? "class" : "struct"); 4241 Diag(Previous->getLocation(), diag::note_previous_use); 4242 return true; 4243 } 4244 return false; 4245} 4246 4247/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4248/// former case, Name will be non-null. In the later case, Name will be null. 4249/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4250/// reference/declaration/definition of a tag. 4251Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4252 SourceLocation KWLoc, const CXXScopeSpec &SS, 4253 IdentifierInfo *Name, SourceLocation NameLoc, 4254 AttributeList *Attr, AccessSpecifier AS, 4255 MultiTemplateParamsArg TemplateParameterLists, 4256 bool &OwnedDecl, bool &IsDependent) { 4257 // If this is not a definition, it must have a name. 4258 assert((Name != 0 || TUK == TUK_Definition) && 4259 "Nameless record must be a definition!"); 4260 4261 OwnedDecl = false; 4262 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4263 4264 // FIXME: Check explicit specializations more carefully. 4265 bool isExplicitSpecialization = false; 4266 if (TUK != TUK_Reference) { 4267 if (TemplateParameterList *TemplateParams 4268 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4269 (TemplateParameterList**)TemplateParameterLists.get(), 4270 TemplateParameterLists.size(), 4271 isExplicitSpecialization)) { 4272 if (TemplateParams->size() > 0) { 4273 // This is a declaration or definition of a class template (which may 4274 // be a member of another template). 4275 OwnedDecl = false; 4276 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4277 SS, Name, NameLoc, Attr, 4278 TemplateParams, 4279 AS); 4280 TemplateParameterLists.release(); 4281 return Result.get(); 4282 } else { 4283 // The "template<>" header is extraneous. 4284 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4285 << ElaboratedType::getNameForTagKind(Kind) << Name; 4286 isExplicitSpecialization = true; 4287 } 4288 } 4289 4290 TemplateParameterLists.release(); 4291 } 4292 4293 DeclContext *SearchDC = CurContext; 4294 DeclContext *DC = CurContext; 4295 NamedDecl *PrevDecl = 0; 4296 bool isStdBadAlloc = false; 4297 bool Invalid = false; 4298 4299 bool RedeclarationOnly = (TUK != TUK_Reference); 4300 4301 if (Name && SS.isNotEmpty()) { 4302 // We have a nested-name tag ('struct foo::bar'). 4303 4304 // Check for invalid 'foo::'. 4305 if (SS.isInvalid()) { 4306 Name = 0; 4307 goto CreateNewDecl; 4308 } 4309 4310 // If this is a friend or a reference to a class in a dependent 4311 // context, don't try to make a decl for it. 4312 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4313 DC = computeDeclContext(SS, false); 4314 if (!DC) { 4315 IsDependent = true; 4316 return DeclPtrTy(); 4317 } 4318 } 4319 4320 if (RequireCompleteDeclContext(SS)) 4321 return DeclPtrTy::make((Decl *)0); 4322 4323 DC = computeDeclContext(SS, true); 4324 SearchDC = DC; 4325 // Look-up name inside 'foo::'. 4326 LookupResult R; 4327 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4328 4329 if (R.isAmbiguous()) { 4330 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4331 return DeclPtrTy(); 4332 } 4333 4334 if (R.getKind() == LookupResult::Found) 4335 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4336 4337 // A tag 'foo::bar' must already exist. 4338 if (!PrevDecl) { 4339 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4340 Name = 0; 4341 Invalid = true; 4342 goto CreateNewDecl; 4343 } 4344 } else if (Name) { 4345 // If this is a named struct, check to see if there was a previous forward 4346 // declaration or definition. 4347 // FIXME: We're looking into outer scopes here, even when we 4348 // shouldn't be. Doing so can result in ambiguities that we 4349 // shouldn't be diagnosing. 4350 LookupResult R; 4351 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4352 if (R.isAmbiguous()) { 4353 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4354 // FIXME: This is not best way to recover from case like: 4355 // 4356 // struct S s; 4357 // 4358 // causes needless "incomplete type" error later. 4359 Name = 0; 4360 PrevDecl = 0; 4361 Invalid = true; 4362 } else 4363 PrevDecl = R.getAsSingleDecl(Context); 4364 4365 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4366 // FIXME: This makes sure that we ignore the contexts associated 4367 // with C structs, unions, and enums when looking for a matching 4368 // tag declaration or definition. See the similar lookup tweak 4369 // in Sema::LookupName; is there a better way to deal with this? 4370 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4371 SearchDC = SearchDC->getParent(); 4372 } 4373 } 4374 4375 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4376 // Maybe we will complain about the shadowed template parameter. 4377 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4378 // Just pretend that we didn't see the previous declaration. 4379 PrevDecl = 0; 4380 } 4381 4382 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4383 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4384 // This is a declaration of or a reference to "std::bad_alloc". 4385 isStdBadAlloc = true; 4386 4387 if (!PrevDecl && StdBadAlloc) { 4388 // std::bad_alloc has been implicitly declared (but made invisible to 4389 // name lookup). Fill in this implicit declaration as the previous 4390 // declaration, so that the declarations get chained appropriately. 4391 PrevDecl = StdBadAlloc; 4392 } 4393 } 4394 4395 if (PrevDecl) { 4396 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4397 // If this is a use of a previous tag, or if the tag is already declared 4398 // in the same scope (so that the definition/declaration completes or 4399 // rementions the tag), reuse the decl. 4400 if (TUK == TUK_Reference || TUK == TUK_Friend || 4401 isDeclInScope(PrevDecl, SearchDC, S)) { 4402 // Make sure that this wasn't declared as an enum and now used as a 4403 // struct or something similar. 4404 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4405 bool SafeToContinue 4406 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4407 Kind != TagDecl::TK_enum); 4408 if (SafeToContinue) 4409 Diag(KWLoc, diag::err_use_with_wrong_tag) 4410 << Name 4411 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4412 PrevTagDecl->getKindName()); 4413 else 4414 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4415 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4416 4417 if (SafeToContinue) 4418 Kind = PrevTagDecl->getTagKind(); 4419 else { 4420 // Recover by making this an anonymous redefinition. 4421 Name = 0; 4422 PrevDecl = 0; 4423 Invalid = true; 4424 } 4425 } 4426 4427 if (!Invalid) { 4428 // If this is a use, just return the declaration we found. 4429 4430 // FIXME: In the future, return a variant or some other clue 4431 // for the consumer of this Decl to know it doesn't own it. 4432 // For our current ASTs this shouldn't be a problem, but will 4433 // need to be changed with DeclGroups. 4434 if (TUK == TUK_Reference || TUK == TUK_Friend) 4435 return DeclPtrTy::make(PrevDecl); 4436 4437 // Diagnose attempts to redefine a tag. 4438 if (TUK == TUK_Definition) { 4439 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4440 // If we're defining a specialization and the previous definition 4441 // is from an implicit instantiation, don't emit an error 4442 // here; we'll catch this in the general case below. 4443 if (!isExplicitSpecialization || 4444 !isa<CXXRecordDecl>(Def) || 4445 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4446 == TSK_ExplicitSpecialization) { 4447 Diag(NameLoc, diag::err_redefinition) << Name; 4448 Diag(Def->getLocation(), diag::note_previous_definition); 4449 // If this is a redefinition, recover by making this 4450 // struct be anonymous, which will make any later 4451 // references get the previous definition. 4452 Name = 0; 4453 PrevDecl = 0; 4454 Invalid = true; 4455 } 4456 } else { 4457 // If the type is currently being defined, complain 4458 // about a nested redefinition. 4459 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4460 if (Tag->isBeingDefined()) { 4461 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4462 Diag(PrevTagDecl->getLocation(), 4463 diag::note_previous_definition); 4464 Name = 0; 4465 PrevDecl = 0; 4466 Invalid = true; 4467 } 4468 } 4469 4470 // Okay, this is definition of a previously declared or referenced 4471 // tag PrevDecl. We're going to create a new Decl for it. 4472 } 4473 } 4474 // If we get here we have (another) forward declaration or we 4475 // have a definition. Just create a new decl. 4476 4477 } else { 4478 // If we get here, this is a definition of a new tag type in a nested 4479 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4480 // new decl/type. We set PrevDecl to NULL so that the entities 4481 // have distinct types. 4482 PrevDecl = 0; 4483 } 4484 // If we get here, we're going to create a new Decl. If PrevDecl 4485 // is non-NULL, it's a definition of the tag declared by 4486 // PrevDecl. If it's NULL, we have a new definition. 4487 } else { 4488 // PrevDecl is a namespace, template, or anything else 4489 // that lives in the IDNS_Tag identifier namespace. 4490 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4491 // The tag name clashes with a namespace name, issue an error and 4492 // recover by making this tag be anonymous. 4493 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4494 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4495 Name = 0; 4496 PrevDecl = 0; 4497 Invalid = true; 4498 } else { 4499 // The existing declaration isn't relevant to us; we're in a 4500 // new scope, so clear out the previous declaration. 4501 PrevDecl = 0; 4502 } 4503 } 4504 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4505 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4506 // C++ [basic.scope.pdecl]p5: 4507 // -- for an elaborated-type-specifier of the form 4508 // 4509 // class-key identifier 4510 // 4511 // if the elaborated-type-specifier is used in the 4512 // decl-specifier-seq or parameter-declaration-clause of a 4513 // function defined in namespace scope, the identifier is 4514 // declared as a class-name in the namespace that contains 4515 // the declaration; otherwise, except as a friend 4516 // declaration, the identifier is declared in the smallest 4517 // non-class, non-function-prototype scope that contains the 4518 // declaration. 4519 // 4520 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4521 // C structs and unions. 4522 // 4523 // GNU C also supports this behavior as part of its incomplete 4524 // enum types extension, while GNU C++ does not. 4525 // 4526 // Find the context where we'll be declaring the tag. 4527 // FIXME: We would like to maintain the current DeclContext as the 4528 // lexical context, 4529 while (SearchDC->isRecord()) 4530 SearchDC = SearchDC->getParent(); 4531 4532 // Find the scope where we'll be declaring the tag. 4533 while (S->isClassScope() || 4534 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4535 ((S->getFlags() & Scope::DeclScope) == 0) || 4536 (S->getEntity() && 4537 ((DeclContext *)S->getEntity())->isTransparentContext())) 4538 S = S->getParent(); 4539 4540 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4541 // C++ [namespace.memdef]p3: 4542 // If a friend declaration in a non-local class first declares a 4543 // class or function, the friend class or function is a member of 4544 // the innermost enclosing namespace. 4545 while (!SearchDC->isFileContext()) 4546 SearchDC = SearchDC->getParent(); 4547 4548 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4549 while (S->getEntity() != SearchDC) 4550 S = S->getParent(); 4551 } 4552 4553CreateNewDecl: 4554 4555 // If there is an identifier, use the location of the identifier as the 4556 // location of the decl, otherwise use the location of the struct/union 4557 // keyword. 4558 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4559 4560 // Otherwise, create a new declaration. If there is a previous 4561 // declaration of the same entity, the two will be linked via 4562 // PrevDecl. 4563 TagDecl *New; 4564 4565 if (Kind == TagDecl::TK_enum) { 4566 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4567 // enum X { A, B, C } D; D should chain to X. 4568 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4569 cast_or_null<EnumDecl>(PrevDecl)); 4570 // If this is an undefined enum, warn. 4571 if (TUK != TUK_Definition && !Invalid) { 4572 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4573 : diag::ext_forward_ref_enum; 4574 Diag(Loc, DK); 4575 } 4576 } else { 4577 // struct/union/class 4578 4579 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4580 // struct X { int A; } D; D should chain to X. 4581 if (getLangOptions().CPlusPlus) { 4582 // FIXME: Look for a way to use RecordDecl for simple structs. 4583 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4584 cast_or_null<CXXRecordDecl>(PrevDecl)); 4585 4586 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4587 StdBadAlloc = cast<CXXRecordDecl>(New); 4588 } else 4589 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4590 cast_or_null<RecordDecl>(PrevDecl)); 4591 } 4592 4593 if (Kind != TagDecl::TK_enum) { 4594 // Handle #pragma pack: if the #pragma pack stack has non-default 4595 // alignment, make up a packed attribute for this decl. These 4596 // attributes are checked when the ASTContext lays out the 4597 // structure. 4598 // 4599 // It is important for implementing the correct semantics that this 4600 // happen here (in act on tag decl). The #pragma pack stack is 4601 // maintained as a result of parser callbacks which can occur at 4602 // many points during the parsing of a struct declaration (because 4603 // the #pragma tokens are effectively skipped over during the 4604 // parsing of the struct). 4605 if (unsigned Alignment = getPragmaPackAlignment()) 4606 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4607 } 4608 4609 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4610 // C++ [dcl.typedef]p3: 4611 // [...] Similarly, in a given scope, a class or enumeration 4612 // shall not be declared with the same name as a typedef-name 4613 // that is declared in that scope and refers to a type other 4614 // than the class or enumeration itself. 4615 LookupResult Lookup; 4616 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4617 TypedefDecl *PrevTypedef = 0; 4618 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4619 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4620 4621 NamedDecl *PrevTypedefNamed = PrevTypedef; 4622 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4623 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4624 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4625 Diag(Loc, diag::err_tag_definition_of_typedef) 4626 << Context.getTypeDeclType(New) 4627 << PrevTypedef->getUnderlyingType(); 4628 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4629 Invalid = true; 4630 } 4631 } 4632 4633 // If this is a specialization of a member class (of a class template), 4634 // check the specialization. 4635 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4636 Invalid = true; 4637 4638 if (Invalid) 4639 New->setInvalidDecl(); 4640 4641 if (Attr) 4642 ProcessDeclAttributeList(S, New, Attr); 4643 4644 // If we're declaring or defining a tag in function prototype scope 4645 // in C, note that this type can only be used within the function. 4646 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4647 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4648 4649 // Set the lexical context. If the tag has a C++ scope specifier, the 4650 // lexical context will be different from the semantic context. 4651 New->setLexicalDeclContext(CurContext); 4652 4653 // Mark this as a friend decl if applicable. 4654 if (TUK == TUK_Friend) 4655 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4656 4657 // Set the access specifier. 4658 if (!Invalid && TUK != TUK_Friend) 4659 SetMemberAccessSpecifier(New, PrevDecl, AS); 4660 4661 if (TUK == TUK_Definition) 4662 New->startDefinition(); 4663 4664 // If this has an identifier, add it to the scope stack. 4665 if (TUK == TUK_Friend) { 4666 // We might be replacing an existing declaration in the lookup tables; 4667 // if so, borrow its access specifier. 4668 if (PrevDecl) 4669 New->setAccess(PrevDecl->getAccess()); 4670 4671 // Friend tag decls are visible in fairly strange ways. 4672 if (!CurContext->isDependentContext()) { 4673 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4674 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4675 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4676 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4677 } 4678 } else if (Name) { 4679 S = getNonFieldDeclScope(S); 4680 PushOnScopeChains(New, S); 4681 } else { 4682 CurContext->addDecl(New); 4683 } 4684 4685 // If this is the C FILE type, notify the AST context. 4686 if (IdentifierInfo *II = New->getIdentifier()) 4687 if (!New->isInvalidDecl() && 4688 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4689 II->isStr("FILE")) 4690 Context.setFILEDecl(New); 4691 4692 OwnedDecl = true; 4693 return DeclPtrTy::make(New); 4694} 4695 4696void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4697 AdjustDeclIfTemplate(TagD); 4698 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4699 4700 // Enter the tag context. 4701 PushDeclContext(S, Tag); 4702 4703 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4704 FieldCollector->StartClass(); 4705 4706 if (Record->getIdentifier()) { 4707 // C++ [class]p2: 4708 // [...] The class-name is also inserted into the scope of the 4709 // class itself; this is known as the injected-class-name. For 4710 // purposes of access checking, the injected-class-name is treated 4711 // as if it were a public member name. 4712 CXXRecordDecl *InjectedClassName 4713 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4714 CurContext, Record->getLocation(), 4715 Record->getIdentifier(), 4716 Record->getTagKeywordLoc(), 4717 Record); 4718 InjectedClassName->setImplicit(); 4719 InjectedClassName->setAccess(AS_public); 4720 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4721 InjectedClassName->setDescribedClassTemplate(Template); 4722 PushOnScopeChains(InjectedClassName, S); 4723 assert(InjectedClassName->isInjectedClassName() && 4724 "Broken injected-class-name"); 4725 } 4726 } 4727} 4728 4729void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4730 SourceLocation RBraceLoc) { 4731 AdjustDeclIfTemplate(TagD); 4732 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4733 Tag->setRBraceLoc(RBraceLoc); 4734 4735 if (isa<CXXRecordDecl>(Tag)) 4736 FieldCollector->FinishClass(); 4737 4738 // Exit this scope of this tag's definition. 4739 PopDeclContext(); 4740 4741 // Notify the consumer that we've defined a tag. 4742 Consumer.HandleTagDeclDefinition(Tag); 4743} 4744 4745// Note that FieldName may be null for anonymous bitfields. 4746bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4747 QualType FieldTy, const Expr *BitWidth, 4748 bool *ZeroWidth) { 4749 // Default to true; that shouldn't confuse checks for emptiness 4750 if (ZeroWidth) 4751 *ZeroWidth = true; 4752 4753 // C99 6.7.2.1p4 - verify the field type. 4754 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4755 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4756 // Handle incomplete types with specific error. 4757 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4758 return true; 4759 if (FieldName) 4760 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4761 << FieldName << FieldTy << BitWidth->getSourceRange(); 4762 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4763 << FieldTy << BitWidth->getSourceRange(); 4764 } 4765 4766 // If the bit-width is type- or value-dependent, don't try to check 4767 // it now. 4768 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4769 return false; 4770 4771 llvm::APSInt Value; 4772 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4773 return true; 4774 4775 if (Value != 0 && ZeroWidth) 4776 *ZeroWidth = false; 4777 4778 // Zero-width bitfield is ok for anonymous field. 4779 if (Value == 0 && FieldName) 4780 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4781 4782 if (Value.isSigned() && Value.isNegative()) { 4783 if (FieldName) 4784 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4785 << FieldName << Value.toString(10); 4786 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4787 << Value.toString(10); 4788 } 4789 4790 if (!FieldTy->isDependentType()) { 4791 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4792 if (Value.getZExtValue() > TypeSize) { 4793 if (FieldName) 4794 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4795 << FieldName << (unsigned)TypeSize; 4796 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4797 << (unsigned)TypeSize; 4798 } 4799 } 4800 4801 return false; 4802} 4803 4804/// ActOnField - Each field of a struct/union/class is passed into this in order 4805/// to create a FieldDecl object for it. 4806Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4807 SourceLocation DeclStart, 4808 Declarator &D, ExprTy *BitfieldWidth) { 4809 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4810 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4811 AS_public); 4812 return DeclPtrTy::make(Res); 4813} 4814 4815/// HandleField - Analyze a field of a C struct or a C++ data member. 4816/// 4817FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4818 SourceLocation DeclStart, 4819 Declarator &D, Expr *BitWidth, 4820 AccessSpecifier AS) { 4821 IdentifierInfo *II = D.getIdentifier(); 4822 SourceLocation Loc = DeclStart; 4823 if (II) Loc = D.getIdentifierLoc(); 4824 4825 DeclaratorInfo *DInfo = 0; 4826 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4827 if (getLangOptions().CPlusPlus) 4828 CheckExtraCXXDefaultArguments(D); 4829 4830 DiagnoseFunctionSpecifiers(D); 4831 4832 if (D.getDeclSpec().isThreadSpecified()) 4833 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4834 4835 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4836 4837 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4838 // Maybe we will complain about the shadowed template parameter. 4839 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4840 // Just pretend that we didn't see the previous declaration. 4841 PrevDecl = 0; 4842 } 4843 4844 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4845 PrevDecl = 0; 4846 4847 bool Mutable 4848 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4849 SourceLocation TSSL = D.getSourceRange().getBegin(); 4850 FieldDecl *NewFD 4851 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4852 AS, PrevDecl, &D); 4853 if (NewFD->isInvalidDecl() && PrevDecl) { 4854 // Don't introduce NewFD into scope; there's already something 4855 // with the same name in the same scope. 4856 } else if (II) { 4857 PushOnScopeChains(NewFD, S); 4858 } else 4859 Record->addDecl(NewFD); 4860 4861 return NewFD; 4862} 4863 4864/// \brief Build a new FieldDecl and check its well-formedness. 4865/// 4866/// This routine builds a new FieldDecl given the fields name, type, 4867/// record, etc. \p PrevDecl should refer to any previous declaration 4868/// with the same name and in the same scope as the field to be 4869/// created. 4870/// 4871/// \returns a new FieldDecl. 4872/// 4873/// \todo The Declarator argument is a hack. It will be removed once 4874FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4875 DeclaratorInfo *DInfo, 4876 RecordDecl *Record, SourceLocation Loc, 4877 bool Mutable, Expr *BitWidth, 4878 SourceLocation TSSL, 4879 AccessSpecifier AS, NamedDecl *PrevDecl, 4880 Declarator *D) { 4881 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4882 bool InvalidDecl = false; 4883 if (D) InvalidDecl = D->isInvalidType(); 4884 4885 // If we receive a broken type, recover by assuming 'int' and 4886 // marking this declaration as invalid. 4887 if (T.isNull()) { 4888 InvalidDecl = true; 4889 T = Context.IntTy; 4890 } 4891 4892 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4893 // than a variably modified type. 4894 if (T->isVariablyModifiedType()) { 4895 bool SizeIsNegative; 4896 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4897 SizeIsNegative); 4898 if (!FixedTy.isNull()) { 4899 Diag(Loc, diag::warn_illegal_constant_array_size); 4900 T = FixedTy; 4901 } else { 4902 if (SizeIsNegative) 4903 Diag(Loc, diag::err_typecheck_negative_array_size); 4904 else 4905 Diag(Loc, diag::err_typecheck_field_variable_size); 4906 InvalidDecl = true; 4907 } 4908 } 4909 4910 // Fields can not have abstract class types 4911 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4912 AbstractFieldType)) 4913 InvalidDecl = true; 4914 4915 bool ZeroWidth = false; 4916 // If this is declared as a bit-field, check the bit-field. 4917 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4918 InvalidDecl = true; 4919 DeleteExpr(BitWidth); 4920 BitWidth = 0; 4921 ZeroWidth = false; 4922 } 4923 4924 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4925 BitWidth, Mutable); 4926 if (InvalidDecl) 4927 NewFD->setInvalidDecl(); 4928 4929 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4930 Diag(Loc, diag::err_duplicate_member) << II; 4931 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4932 NewFD->setInvalidDecl(); 4933 } 4934 4935 if (getLangOptions().CPlusPlus) { 4936 QualType EltTy = Context.getBaseElementType(T); 4937 4938 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4939 4940 if (!T->isPODType()) 4941 CXXRecord->setPOD(false); 4942 if (!ZeroWidth) 4943 CXXRecord->setEmpty(false); 4944 4945 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4946 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4947 4948 if (!RDecl->hasTrivialConstructor()) 4949 CXXRecord->setHasTrivialConstructor(false); 4950 if (!RDecl->hasTrivialCopyConstructor()) 4951 CXXRecord->setHasTrivialCopyConstructor(false); 4952 if (!RDecl->hasTrivialCopyAssignment()) 4953 CXXRecord->setHasTrivialCopyAssignment(false); 4954 if (!RDecl->hasTrivialDestructor()) 4955 CXXRecord->setHasTrivialDestructor(false); 4956 4957 // C++ 9.5p1: An object of a class with a non-trivial 4958 // constructor, a non-trivial copy constructor, a non-trivial 4959 // destructor, or a non-trivial copy assignment operator 4960 // cannot be a member of a union, nor can an array of such 4961 // objects. 4962 // TODO: C++0x alters this restriction significantly. 4963 if (Record->isUnion()) { 4964 // We check for copy constructors before constructors 4965 // because otherwise we'll never get complaints about 4966 // copy constructors. 4967 4968 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4969 4970 CXXSpecialMember member; 4971 if (!RDecl->hasTrivialCopyConstructor()) 4972 member = CXXCopyConstructor; 4973 else if (!RDecl->hasTrivialConstructor()) 4974 member = CXXDefaultConstructor; 4975 else if (!RDecl->hasTrivialCopyAssignment()) 4976 member = CXXCopyAssignment; 4977 else if (!RDecl->hasTrivialDestructor()) 4978 member = CXXDestructor; 4979 else 4980 member = invalid; 4981 4982 if (member != invalid) { 4983 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4984 DiagnoseNontrivial(RT, member); 4985 NewFD->setInvalidDecl(); 4986 } 4987 } 4988 } 4989 } 4990 4991 // FIXME: We need to pass in the attributes given an AST 4992 // representation, not a parser representation. 4993 if (D) 4994 // FIXME: What to pass instead of TUScope? 4995 ProcessDeclAttributes(TUScope, NewFD, *D); 4996 4997 if (T.isObjCGCWeak()) 4998 Diag(Loc, diag::warn_attribute_weak_on_field); 4999 5000 NewFD->setAccess(AS); 5001 5002 // C++ [dcl.init.aggr]p1: 5003 // An aggregate is an array or a class (clause 9) with [...] no 5004 // private or protected non-static data members (clause 11). 5005 // A POD must be an aggregate. 5006 if (getLangOptions().CPlusPlus && 5007 (AS == AS_private || AS == AS_protected)) { 5008 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5009 CXXRecord->setAggregate(false); 5010 CXXRecord->setPOD(false); 5011 } 5012 5013 return NewFD; 5014} 5015 5016/// DiagnoseNontrivial - Given that a class has a non-trivial 5017/// special member, figure out why. 5018void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5019 QualType QT(T, 0U); 5020 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5021 5022 // Check whether the member was user-declared. 5023 switch (member) { 5024 case CXXDefaultConstructor: 5025 if (RD->hasUserDeclaredConstructor()) { 5026 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5027 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5028 const FunctionDecl *body = 0; 5029 ci->getBody(body); 5030 if (!body || 5031 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5032 SourceLocation CtorLoc = ci->getLocation(); 5033 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5034 return; 5035 } 5036 } 5037 5038 assert(0 && "found no user-declared constructors"); 5039 return; 5040 } 5041 break; 5042 5043 case CXXCopyConstructor: 5044 if (RD->hasUserDeclaredCopyConstructor()) { 5045 SourceLocation CtorLoc = 5046 RD->getCopyConstructor(Context, 0)->getLocation(); 5047 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5048 return; 5049 } 5050 break; 5051 5052 case CXXCopyAssignment: 5053 if (RD->hasUserDeclaredCopyAssignment()) { 5054 // FIXME: this should use the location of the copy 5055 // assignment, not the type. 5056 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5057 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5058 return; 5059 } 5060 break; 5061 5062 case CXXDestructor: 5063 if (RD->hasUserDeclaredDestructor()) { 5064 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5065 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5066 return; 5067 } 5068 break; 5069 } 5070 5071 typedef CXXRecordDecl::base_class_iterator base_iter; 5072 5073 // Virtual bases and members inhibit trivial copying/construction, 5074 // but not trivial destruction. 5075 if (member != CXXDestructor) { 5076 // Check for virtual bases. vbases includes indirect virtual bases, 5077 // so we just iterate through the direct bases. 5078 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5079 if (bi->isVirtual()) { 5080 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5081 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5082 return; 5083 } 5084 5085 // Check for virtual methods. 5086 typedef CXXRecordDecl::method_iterator meth_iter; 5087 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5088 ++mi) { 5089 if (mi->isVirtual()) { 5090 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5091 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5092 return; 5093 } 5094 } 5095 } 5096 5097 bool (CXXRecordDecl::*hasTrivial)() const; 5098 switch (member) { 5099 case CXXDefaultConstructor: 5100 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5101 case CXXCopyConstructor: 5102 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5103 case CXXCopyAssignment: 5104 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5105 case CXXDestructor: 5106 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5107 default: 5108 assert(0 && "unexpected special member"); return; 5109 } 5110 5111 // Check for nontrivial bases (and recurse). 5112 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5113 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5114 assert(BaseRT && "Don't know how to handle dependent bases"); 5115 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5116 if (!(BaseRecTy->*hasTrivial)()) { 5117 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5118 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5119 DiagnoseNontrivial(BaseRT, member); 5120 return; 5121 } 5122 } 5123 5124 // Check for nontrivial members (and recurse). 5125 typedef RecordDecl::field_iterator field_iter; 5126 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5127 ++fi) { 5128 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5129 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5130 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5131 5132 if (!(EltRD->*hasTrivial)()) { 5133 SourceLocation FLoc = (*fi)->getLocation(); 5134 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5135 DiagnoseNontrivial(EltRT, member); 5136 return; 5137 } 5138 } 5139 } 5140 5141 assert(0 && "found no explanation for non-trivial member"); 5142} 5143 5144/// TranslateIvarVisibility - Translate visibility from a token ID to an 5145/// AST enum value. 5146static ObjCIvarDecl::AccessControl 5147TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5148 switch (ivarVisibility) { 5149 default: assert(0 && "Unknown visitibility kind"); 5150 case tok::objc_private: return ObjCIvarDecl::Private; 5151 case tok::objc_public: return ObjCIvarDecl::Public; 5152 case tok::objc_protected: return ObjCIvarDecl::Protected; 5153 case tok::objc_package: return ObjCIvarDecl::Package; 5154 } 5155} 5156 5157/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5158/// in order to create an IvarDecl object for it. 5159Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5160 SourceLocation DeclStart, 5161 DeclPtrTy IntfDecl, 5162 Declarator &D, ExprTy *BitfieldWidth, 5163 tok::ObjCKeywordKind Visibility) { 5164 5165 IdentifierInfo *II = D.getIdentifier(); 5166 Expr *BitWidth = (Expr*)BitfieldWidth; 5167 SourceLocation Loc = DeclStart; 5168 if (II) Loc = D.getIdentifierLoc(); 5169 5170 // FIXME: Unnamed fields can be handled in various different ways, for 5171 // example, unnamed unions inject all members into the struct namespace! 5172 5173 DeclaratorInfo *DInfo = 0; 5174 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5175 5176 if (BitWidth) { 5177 // 6.7.2.1p3, 6.7.2.1p4 5178 if (VerifyBitField(Loc, II, T, BitWidth)) { 5179 D.setInvalidType(); 5180 DeleteExpr(BitWidth); 5181 BitWidth = 0; 5182 } 5183 } else { 5184 // Not a bitfield. 5185 5186 // validate II. 5187 5188 } 5189 5190 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5191 // than a variably modified type. 5192 if (T->isVariablyModifiedType()) { 5193 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5194 D.setInvalidType(); 5195 } 5196 5197 // Get the visibility (access control) for this ivar. 5198 ObjCIvarDecl::AccessControl ac = 5199 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5200 : ObjCIvarDecl::None; 5201 // Must set ivar's DeclContext to its enclosing interface. 5202 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5203 DeclContext *EnclosingContext; 5204 if (ObjCImplementationDecl *IMPDecl = 5205 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5206 // Case of ivar declared in an implementation. Context is that of its class. 5207 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5208 assert(IDecl && "No class- ActOnIvar"); 5209 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5210 } else 5211 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5212 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5213 5214 // Construct the decl. 5215 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5216 EnclosingContext, Loc, II, T, 5217 DInfo, ac, (Expr *)BitfieldWidth); 5218 5219 if (II) { 5220 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5221 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5222 && !isa<TagDecl>(PrevDecl)) { 5223 Diag(Loc, diag::err_duplicate_member) << II; 5224 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5225 NewID->setInvalidDecl(); 5226 } 5227 } 5228 5229 // Process attributes attached to the ivar. 5230 ProcessDeclAttributes(S, NewID, D); 5231 5232 if (D.isInvalidType()) 5233 NewID->setInvalidDecl(); 5234 5235 if (II) { 5236 // FIXME: When interfaces are DeclContexts, we'll need to add 5237 // these to the interface. 5238 S->AddDecl(DeclPtrTy::make(NewID)); 5239 IdResolver.AddDecl(NewID); 5240 } 5241 5242 return DeclPtrTy::make(NewID); 5243} 5244 5245void Sema::ActOnFields(Scope* S, 5246 SourceLocation RecLoc, DeclPtrTy RecDecl, 5247 DeclPtrTy *Fields, unsigned NumFields, 5248 SourceLocation LBrac, SourceLocation RBrac, 5249 AttributeList *Attr) { 5250 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5251 assert(EnclosingDecl && "missing record or interface decl"); 5252 5253 // If the decl this is being inserted into is invalid, then it may be a 5254 // redeclaration or some other bogus case. Don't try to add fields to it. 5255 if (EnclosingDecl->isInvalidDecl()) { 5256 // FIXME: Deallocate fields? 5257 return; 5258 } 5259 5260 5261 // Verify that all the fields are okay. 5262 unsigned NumNamedMembers = 0; 5263 llvm::SmallVector<FieldDecl*, 32> RecFields; 5264 5265 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5266 for (unsigned i = 0; i != NumFields; ++i) { 5267 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5268 5269 // Get the type for the field. 5270 Type *FDTy = FD->getType().getTypePtr(); 5271 5272 if (!FD->isAnonymousStructOrUnion()) { 5273 // Remember all fields written by the user. 5274 RecFields.push_back(FD); 5275 } 5276 5277 // If the field is already invalid for some reason, don't emit more 5278 // diagnostics about it. 5279 if (FD->isInvalidDecl()) 5280 continue; 5281 5282 // C99 6.7.2.1p2: 5283 // A structure or union shall not contain a member with 5284 // incomplete or function type (hence, a structure shall not 5285 // contain an instance of itself, but may contain a pointer to 5286 // an instance of itself), except that the last member of a 5287 // structure with more than one named member may have incomplete 5288 // array type; such a structure (and any union containing, 5289 // possibly recursively, a member that is such a structure) 5290 // shall not be a member of a structure or an element of an 5291 // array. 5292 if (FDTy->isFunctionType()) { 5293 // Field declared as a function. 5294 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5295 << FD->getDeclName(); 5296 FD->setInvalidDecl(); 5297 EnclosingDecl->setInvalidDecl(); 5298 continue; 5299 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5300 Record && Record->isStruct()) { 5301 // Flexible array member. 5302 if (NumNamedMembers < 1) { 5303 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5304 << FD->getDeclName(); 5305 FD->setInvalidDecl(); 5306 EnclosingDecl->setInvalidDecl(); 5307 continue; 5308 } 5309 // Okay, we have a legal flexible array member at the end of the struct. 5310 if (Record) 5311 Record->setHasFlexibleArrayMember(true); 5312 } else if (!FDTy->isDependentType() && 5313 RequireCompleteType(FD->getLocation(), FD->getType(), 5314 diag::err_field_incomplete)) { 5315 // Incomplete type 5316 FD->setInvalidDecl(); 5317 EnclosingDecl->setInvalidDecl(); 5318 continue; 5319 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5320 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5321 // If this is a member of a union, then entire union becomes "flexible". 5322 if (Record && Record->isUnion()) { 5323 Record->setHasFlexibleArrayMember(true); 5324 } else { 5325 // If this is a struct/class and this is not the last element, reject 5326 // it. Note that GCC supports variable sized arrays in the middle of 5327 // structures. 5328 if (i != NumFields-1) 5329 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5330 << FD->getDeclName() << FD->getType(); 5331 else { 5332 // We support flexible arrays at the end of structs in 5333 // other structs as an extension. 5334 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5335 << FD->getDeclName(); 5336 if (Record) 5337 Record->setHasFlexibleArrayMember(true); 5338 } 5339 } 5340 } 5341 if (Record && FDTTy->getDecl()->hasObjectMember()) 5342 Record->setHasObjectMember(true); 5343 } else if (FDTy->isObjCInterfaceType()) { 5344 /// A field cannot be an Objective-c object 5345 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5346 FD->setInvalidDecl(); 5347 EnclosingDecl->setInvalidDecl(); 5348 continue; 5349 } else if (getLangOptions().ObjC1 && 5350 getLangOptions().getGCMode() != LangOptions::NonGC && 5351 Record && 5352 (FD->getType()->isObjCObjectPointerType() || 5353 FD->getType().isObjCGCStrong())) 5354 Record->setHasObjectMember(true); 5355 // Keep track of the number of named members. 5356 if (FD->getIdentifier()) 5357 ++NumNamedMembers; 5358 } 5359 5360 // Okay, we successfully defined 'Record'. 5361 if (Record) { 5362 Record->completeDefinition(Context); 5363 } else { 5364 ObjCIvarDecl **ClsFields = 5365 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5366 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5367 ID->setIVarList(ClsFields, RecFields.size(), Context); 5368 ID->setLocEnd(RBrac); 5369 // Add ivar's to class's DeclContext. 5370 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5371 ClsFields[i]->setLexicalDeclContext(ID); 5372 ID->addDecl(ClsFields[i]); 5373 } 5374 // Must enforce the rule that ivars in the base classes may not be 5375 // duplicates. 5376 if (ID->getSuperClass()) { 5377 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5378 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5379 ObjCIvarDecl* Ivar = (*IVI); 5380 5381 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5382 ObjCIvarDecl* prevIvar = 5383 ID->getSuperClass()->lookupInstanceVariable(II); 5384 if (prevIvar) { 5385 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5386 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5387 } 5388 } 5389 } 5390 } 5391 } else if (ObjCImplementationDecl *IMPDecl = 5392 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5393 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5394 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5395 // Ivar declared in @implementation never belongs to the implementation. 5396 // Only it is in implementation's lexical context. 5397 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5398 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5399 } 5400 } 5401 5402 if (Attr) 5403 ProcessDeclAttributeList(S, Record, Attr); 5404} 5405 5406EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5407 EnumConstantDecl *LastEnumConst, 5408 SourceLocation IdLoc, 5409 IdentifierInfo *Id, 5410 ExprArg val) { 5411 Expr *Val = (Expr *)val.get(); 5412 5413 llvm::APSInt EnumVal(32); 5414 QualType EltTy; 5415 if (Val) { 5416 if (Val->isTypeDependent()) 5417 EltTy = Context.DependentTy; 5418 else { 5419 // Make sure to promote the operand type to int. 5420 UsualUnaryConversions(Val); 5421 if (Val != val.get()) { 5422 val.release(); 5423 val = Val; 5424 } 5425 5426 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5427 SourceLocation ExpLoc; 5428 if (!Val->isValueDependent() && 5429 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5430 Val = 0; 5431 } else { 5432 EltTy = Val->getType(); 5433 } 5434 } 5435 } 5436 5437 if (!Val) { 5438 if (LastEnumConst) { 5439 // Assign the last value + 1. 5440 EnumVal = LastEnumConst->getInitVal(); 5441 ++EnumVal; 5442 5443 // Check for overflow on increment. 5444 if (EnumVal < LastEnumConst->getInitVal()) 5445 Diag(IdLoc, diag::warn_enum_value_overflow); 5446 5447 EltTy = LastEnumConst->getType(); 5448 } else { 5449 // First value, set to zero. 5450 EltTy = Context.IntTy; 5451 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5452 } 5453 } 5454 5455 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5456 5457 val.release(); 5458 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5459 Val, EnumVal); 5460} 5461 5462 5463Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5464 DeclPtrTy lastEnumConst, 5465 SourceLocation IdLoc, 5466 IdentifierInfo *Id, 5467 SourceLocation EqualLoc, ExprTy *val) { 5468 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5469 EnumConstantDecl *LastEnumConst = 5470 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5471 Expr *Val = static_cast<Expr*>(val); 5472 5473 // The scope passed in may not be a decl scope. Zip up the scope tree until 5474 // we find one that is. 5475 S = getNonFieldDeclScope(S); 5476 5477 // Verify that there isn't already something declared with this name in this 5478 // scope. 5479 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5480 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5481 // Maybe we will complain about the shadowed template parameter. 5482 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5483 // Just pretend that we didn't see the previous declaration. 5484 PrevDecl = 0; 5485 } 5486 5487 if (PrevDecl) { 5488 // When in C++, we may get a TagDecl with the same name; in this case the 5489 // enum constant will 'hide' the tag. 5490 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5491 "Received TagDecl when not in C++!"); 5492 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5493 if (isa<EnumConstantDecl>(PrevDecl)) 5494 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5495 else 5496 Diag(IdLoc, diag::err_redefinition) << Id; 5497 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5498 if (Val) Val->Destroy(Context); 5499 return DeclPtrTy(); 5500 } 5501 } 5502 5503 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5504 IdLoc, Id, Owned(Val)); 5505 5506 // Register this decl in the current scope stack. 5507 if (New) 5508 PushOnScopeChains(New, S); 5509 5510 return DeclPtrTy::make(New); 5511} 5512 5513void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5514 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5515 DeclPtrTy *Elements, unsigned NumElements, 5516 Scope *S, AttributeList *Attr) { 5517 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5518 QualType EnumType = Context.getTypeDeclType(Enum); 5519 5520 if (Attr) 5521 ProcessDeclAttributeList(S, Enum, Attr); 5522 5523 // TODO: If the result value doesn't fit in an int, it must be a long or long 5524 // long value. ISO C does not support this, but GCC does as an extension, 5525 // emit a warning. 5526 unsigned IntWidth = Context.Target.getIntWidth(); 5527 unsigned CharWidth = Context.Target.getCharWidth(); 5528 unsigned ShortWidth = Context.Target.getShortWidth(); 5529 5530 // Verify that all the values are okay, compute the size of the values, and 5531 // reverse the list. 5532 unsigned NumNegativeBits = 0; 5533 unsigned NumPositiveBits = 0; 5534 5535 // Keep track of whether all elements have type int. 5536 bool AllElementsInt = true; 5537 5538 for (unsigned i = 0; i != NumElements; ++i) { 5539 EnumConstantDecl *ECD = 5540 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5541 if (!ECD) continue; // Already issued a diagnostic. 5542 5543 // If the enum value doesn't fit in an int, emit an extension warning. 5544 const llvm::APSInt &InitVal = ECD->getInitVal(); 5545 assert(InitVal.getBitWidth() >= IntWidth && 5546 "Should have promoted value to int"); 5547 if (InitVal.getBitWidth() > IntWidth) { 5548 llvm::APSInt V(InitVal); 5549 V.trunc(IntWidth); 5550 V.extend(InitVal.getBitWidth()); 5551 if (V != InitVal) 5552 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5553 << InitVal.toString(10); 5554 } 5555 5556 // Keep track of the size of positive and negative values. 5557 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5558 NumPositiveBits = std::max(NumPositiveBits, 5559 (unsigned)InitVal.getActiveBits()); 5560 else 5561 NumNegativeBits = std::max(NumNegativeBits, 5562 (unsigned)InitVal.getMinSignedBits()); 5563 5564 // Keep track of whether every enum element has type int (very commmon). 5565 if (AllElementsInt) 5566 AllElementsInt = ECD->getType() == Context.IntTy; 5567 } 5568 5569 // Figure out the type that should be used for this enum. 5570 // FIXME: Support -fshort-enums. 5571 QualType BestType; 5572 unsigned BestWidth; 5573 5574 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5575 5576 if (NumNegativeBits) { 5577 // If there is a negative value, figure out the smallest integer type (of 5578 // int/long/longlong) that fits. 5579 // If it's packed, check also if it fits a char or a short. 5580 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5581 BestType = Context.SignedCharTy; 5582 BestWidth = CharWidth; 5583 } else if (Packed && NumNegativeBits <= ShortWidth && 5584 NumPositiveBits < ShortWidth) { 5585 BestType = Context.ShortTy; 5586 BestWidth = ShortWidth; 5587 } 5588 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5589 BestType = Context.IntTy; 5590 BestWidth = IntWidth; 5591 } else { 5592 BestWidth = Context.Target.getLongWidth(); 5593 5594 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5595 BestType = Context.LongTy; 5596 else { 5597 BestWidth = Context.Target.getLongLongWidth(); 5598 5599 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5600 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5601 BestType = Context.LongLongTy; 5602 } 5603 } 5604 } else { 5605 // If there is no negative value, figure out which of uint, ulong, ulonglong 5606 // fits. 5607 // If it's packed, check also if it fits a char or a short. 5608 if (Packed && NumPositiveBits <= CharWidth) { 5609 BestType = Context.UnsignedCharTy; 5610 BestWidth = CharWidth; 5611 } else if (Packed && NumPositiveBits <= ShortWidth) { 5612 BestType = Context.UnsignedShortTy; 5613 BestWidth = ShortWidth; 5614 } 5615 else if (NumPositiveBits <= IntWidth) { 5616 BestType = Context.UnsignedIntTy; 5617 BestWidth = IntWidth; 5618 } else if (NumPositiveBits <= 5619 (BestWidth = Context.Target.getLongWidth())) { 5620 BestType = Context.UnsignedLongTy; 5621 } else { 5622 BestWidth = Context.Target.getLongLongWidth(); 5623 assert(NumPositiveBits <= BestWidth && 5624 "How could an initializer get larger than ULL?"); 5625 BestType = Context.UnsignedLongLongTy; 5626 } 5627 } 5628 5629 // Loop over all of the enumerator constants, changing their types to match 5630 // the type of the enum if needed. 5631 for (unsigned i = 0; i != NumElements; ++i) { 5632 EnumConstantDecl *ECD = 5633 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5634 if (!ECD) continue; // Already issued a diagnostic. 5635 5636 // Standard C says the enumerators have int type, but we allow, as an 5637 // extension, the enumerators to be larger than int size. If each 5638 // enumerator value fits in an int, type it as an int, otherwise type it the 5639 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5640 // that X has type 'int', not 'unsigned'. 5641 if (ECD->getType() == Context.IntTy) { 5642 // Make sure the init value is signed. 5643 llvm::APSInt IV = ECD->getInitVal(); 5644 IV.setIsSigned(true); 5645 ECD->setInitVal(IV); 5646 5647 if (getLangOptions().CPlusPlus) 5648 // C++ [dcl.enum]p4: Following the closing brace of an 5649 // enum-specifier, each enumerator has the type of its 5650 // enumeration. 5651 ECD->setType(EnumType); 5652 continue; // Already int type. 5653 } 5654 5655 // Determine whether the value fits into an int. 5656 llvm::APSInt InitVal = ECD->getInitVal(); 5657 bool FitsInInt; 5658 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5659 FitsInInt = InitVal.getActiveBits() < IntWidth; 5660 else 5661 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5662 5663 // If it fits into an integer type, force it. Otherwise force it to match 5664 // the enum decl type. 5665 QualType NewTy; 5666 unsigned NewWidth; 5667 bool NewSign; 5668 if (FitsInInt) { 5669 NewTy = Context.IntTy; 5670 NewWidth = IntWidth; 5671 NewSign = true; 5672 } else if (ECD->getType() == BestType) { 5673 // Already the right type! 5674 if (getLangOptions().CPlusPlus) 5675 // C++ [dcl.enum]p4: Following the closing brace of an 5676 // enum-specifier, each enumerator has the type of its 5677 // enumeration. 5678 ECD->setType(EnumType); 5679 continue; 5680 } else { 5681 NewTy = BestType; 5682 NewWidth = BestWidth; 5683 NewSign = BestType->isSignedIntegerType(); 5684 } 5685 5686 // Adjust the APSInt value. 5687 InitVal.extOrTrunc(NewWidth); 5688 InitVal.setIsSigned(NewSign); 5689 ECD->setInitVal(InitVal); 5690 5691 // Adjust the Expr initializer and type. 5692 if (ECD->getInitExpr()) 5693 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5694 CastExpr::CK_IntegralCast, 5695 ECD->getInitExpr(), 5696 /*isLvalue=*/false)); 5697 if (getLangOptions().CPlusPlus) 5698 // C++ [dcl.enum]p4: Following the closing brace of an 5699 // enum-specifier, each enumerator has the type of its 5700 // enumeration. 5701 ECD->setType(EnumType); 5702 else 5703 ECD->setType(NewTy); 5704 } 5705 5706 Enum->completeDefinition(Context, BestType); 5707} 5708 5709Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5710 ExprArg expr) { 5711 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5712 5713 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5714 Loc, AsmString); 5715 CurContext->addDecl(New); 5716 return DeclPtrTy::make(New); 5717} 5718 5719void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5720 SourceLocation PragmaLoc, 5721 SourceLocation NameLoc) { 5722 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5723 5724 if (PrevDecl) { 5725 PrevDecl->addAttr(::new (Context) WeakAttr()); 5726 } else { 5727 (void)WeakUndeclaredIdentifiers.insert( 5728 std::pair<IdentifierInfo*,WeakInfo> 5729 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5730 } 5731} 5732 5733void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5734 IdentifierInfo* AliasName, 5735 SourceLocation PragmaLoc, 5736 SourceLocation NameLoc, 5737 SourceLocation AliasNameLoc) { 5738 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5739 WeakInfo W = WeakInfo(Name, NameLoc); 5740 5741 if (PrevDecl) { 5742 if (!PrevDecl->hasAttr<AliasAttr>()) 5743 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5744 DeclApplyPragmaWeak(TUScope, ND, W); 5745 } else { 5746 (void)WeakUndeclaredIdentifiers.insert( 5747 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5748 } 5749} 5750