SemaDecl.cpp revision a24dc2e38c7fb0f7f138b3d14b5f0f241fd0eccf
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(*this, &II, NameLoc, LookupOrdinaryName); 91 LookupParsedName(Result, S, SS, false); 92 93 NamedDecl *IIDecl = 0; 94 switch (Result.getResultKind()) { 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 Result.suppressDiagnostics(); 107 return 0; 108 } 109 110 // Look to see if we have a type anywhere in the list of results. 111 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 112 Res != ResEnd; ++Res) { 113 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 114 if (!IIDecl || 115 (*Res)->getLocation().getRawEncoding() < 116 IIDecl->getLocation().getRawEncoding()) 117 IIDecl = *Res; 118 } 119 } 120 121 if (!IIDecl) { 122 // None of the entities we found is a type, so there is no way 123 // to even assume that the result is a type. In this case, don't 124 // complain about the ambiguity. The parser will either try to 125 // perform this lookup again (e.g., as an object name), which 126 // will produce the ambiguity, or will complain that it expected 127 // a type name. 128 Result.suppressDiagnostics(); 129 return 0; 130 } 131 132 // We found a type within the ambiguous lookup; diagnose the 133 // ambiguity and then return that type. This might be the right 134 // answer, or it might not be, but it suppresses any attempt to 135 // perform the name lookup again. 136 break; 137 138 case LookupResult::Found: 139 IIDecl = Result.getFoundDecl(); 140 break; 141 } 142 143 assert(IIDecl && "Didn't find decl"); 144 145 QualType T; 146 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 147 DiagnoseUseOfDecl(IIDecl, NameLoc); 148 149 // C++ [temp.local]p2: 150 // Within the scope of a class template specialization or 151 // partial specialization, when the injected-class-name is 152 // not followed by a <, it is equivalent to the 153 // injected-class-name followed by the template-argument s 154 // of the class template specialization or partial 155 // specialization enclosed in <>. 156 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 157 if (RD->isInjectedClassName()) 158 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 159 T = Template->getInjectedClassNameType(Context); 160 161 if (T.isNull()) 162 T = Context.getTypeDeclType(TD); 163 164 if (SS) 165 T = getQualifiedNameType(*SS, T); 166 167 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 168 T = Context.getObjCInterfaceType(IDecl); 169 } else { 170 // If it's not plausibly a type, suppress diagnostics. 171 Result.suppressDiagnostics(); 172 return 0; 173 } 174 175 return T.getAsOpaquePtr(); 176} 177 178/// isTagName() - This method is called *for error recovery purposes only* 179/// to determine if the specified name is a valid tag name ("struct foo"). If 180/// so, this returns the TST for the tag corresponding to it (TST_enum, 181/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 182/// where the user forgot to specify the tag. 183DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 184 // Do a tag name lookup in this scope. 185 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 186 LookupName(R, S, false); 187 R.suppressDiagnostics(); 188 if (R.getResultKind() == LookupResult::Found) 189 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 190 switch (TD->getTagKind()) { 191 case TagDecl::TK_struct: return DeclSpec::TST_struct; 192 case TagDecl::TK_union: return DeclSpec::TST_union; 193 case TagDecl::TK_class: return DeclSpec::TST_class; 194 case TagDecl::TK_enum: return DeclSpec::TST_enum; 195 } 196 } 197 198 return DeclSpec::TST_unspecified; 199} 200 201bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 202 SourceLocation IILoc, 203 Scope *S, 204 const CXXScopeSpec *SS, 205 TypeTy *&SuggestedType) { 206 // We don't have anything to suggest (yet). 207 SuggestedType = 0; 208 209 // FIXME: Should we move the logic that tries to recover from a missing tag 210 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 211 212 if (!SS) 213 Diag(IILoc, diag::err_unknown_typename) << &II; 214 else if (DeclContext *DC = computeDeclContext(*SS, false)) 215 Diag(IILoc, diag::err_typename_nested_not_found) 216 << &II << DC << SS->getRange(); 217 else if (isDependentScopeSpecifier(*SS)) { 218 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 219 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 220 << SourceRange(SS->getRange().getBegin(), IILoc) 221 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 222 "typename "); 223 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 224 } else { 225 assert(SS && SS->isInvalid() && 226 "Invalid scope specifier has already been diagnosed"); 227 } 228 229 return true; 230} 231 232// Determines the context to return to after temporarily entering a 233// context. This depends in an unnecessarily complicated way on the 234// exact ordering of callbacks from the parser. 235DeclContext *Sema::getContainingDC(DeclContext *DC) { 236 237 // Functions defined inline within classes aren't parsed until we've 238 // finished parsing the top-level class, so the top-level class is 239 // the context we'll need to return to. 240 if (isa<FunctionDecl>(DC)) { 241 DC = DC->getLexicalParent(); 242 243 // A function not defined within a class will always return to its 244 // lexical context. 245 if (!isa<CXXRecordDecl>(DC)) 246 return DC; 247 248 // A C++ inline method/friend is parsed *after* the topmost class 249 // it was declared in is fully parsed ("complete"); the topmost 250 // class is the context we need to return to. 251 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 252 DC = RD; 253 254 // Return the declaration context of the topmost class the inline method is 255 // declared in. 256 return DC; 257 } 258 259 if (isa<ObjCMethodDecl>(DC)) 260 return Context.getTranslationUnitDecl(); 261 262 return DC->getLexicalParent(); 263} 264 265void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 266 assert(getContainingDC(DC) == CurContext && 267 "The next DeclContext should be lexically contained in the current one."); 268 CurContext = DC; 269 S->setEntity(DC); 270} 271 272void Sema::PopDeclContext() { 273 assert(CurContext && "DeclContext imbalance!"); 274 275 CurContext = getContainingDC(CurContext); 276} 277 278/// EnterDeclaratorContext - Used when we must lookup names in the context 279/// of a declarator's nested name specifier. 280void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 281 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 282 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 283 CurContext = DC; 284 assert(CurContext && "No context?"); 285 S->setEntity(CurContext); 286} 287 288void Sema::ExitDeclaratorContext(Scope *S) { 289 S->setEntity(PreDeclaratorDC); 290 PreDeclaratorDC = 0; 291 292 // Reset CurContext to the nearest enclosing context. 293 while (!S->getEntity() && S->getParent()) 294 S = S->getParent(); 295 CurContext = static_cast<DeclContext*>(S->getEntity()); 296 assert(CurContext && "No context?"); 297} 298 299/// \brief Determine whether we allow overloading of the function 300/// PrevDecl with another declaration. 301/// 302/// This routine determines whether overloading is possible, not 303/// whether some new function is actually an overload. It will return 304/// true in C++ (where we can always provide overloads) or, as an 305/// extension, in C when the previous function is already an 306/// overloaded function declaration or has the "overloadable" 307/// attribute. 308static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 309 if (Context.getLangOptions().CPlusPlus) 310 return true; 311 312 if (isa<OverloadedFunctionDecl>(PrevDecl)) 313 return true; 314 315 return PrevDecl->getAttr<OverloadableAttr>() != 0; 316} 317 318/// Add this decl to the scope shadowed decl chains. 319void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 320 // Move up the scope chain until we find the nearest enclosing 321 // non-transparent context. The declaration will be introduced into this 322 // scope. 323 while (S->getEntity() && 324 ((DeclContext *)S->getEntity())->isTransparentContext()) 325 S = S->getParent(); 326 327 // Add scoped declarations into their context, so that they can be 328 // found later. Declarations without a context won't be inserted 329 // into any context. 330 if (AddToContext) 331 CurContext->addDecl(D); 332 333 // Out-of-line function and variable definitions should not be pushed into 334 // scope. 335 if ((isa<FunctionTemplateDecl>(D) && 336 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 337 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 338 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 339 return; 340 341 // If this replaces anything in the current scope, 342 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 343 IEnd = IdResolver.end(); 344 for (; I != IEnd; ++I) { 345 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 346 S->RemoveDecl(DeclPtrTy::make(*I)); 347 IdResolver.RemoveDecl(*I); 348 349 // Should only need to replace one decl. 350 break; 351 } 352 } 353 354 S->AddDecl(DeclPtrTy::make(D)); 355 IdResolver.AddDecl(D); 356} 357 358bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 359 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 360 // Look inside the overload set to determine if any of the declarations 361 // are in scope. (Possibly) build a new overload set containing only 362 // those declarations that are in scope. 363 OverloadedFunctionDecl *NewOvl = 0; 364 bool FoundInScope = false; 365 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 366 FEnd = Ovl->function_end(); 367 F != FEnd; ++F) { 368 NamedDecl *FD = F->get(); 369 if (!isDeclInScope(FD, Ctx, S)) { 370 if (!NewOvl && F != Ovl->function_begin()) { 371 NewOvl = OverloadedFunctionDecl::Create(Context, 372 F->get()->getDeclContext(), 373 F->get()->getDeclName()); 374 D = NewOvl; 375 for (OverloadedFunctionDecl::function_iterator 376 First = Ovl->function_begin(); 377 First != F; ++First) 378 NewOvl->addOverload(*First); 379 } 380 } else { 381 FoundInScope = true; 382 if (NewOvl) 383 NewOvl->addOverload(*F); 384 } 385 } 386 387 return FoundInScope; 388 } 389 390 return IdResolver.isDeclInScope(D, Ctx, Context, S); 391} 392 393static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 394 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 395 return false; 396 397 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 398 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 399 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 400 if (!RD->hasTrivialConstructor()) 401 return false; 402 if (!RD->hasTrivialDestructor()) 403 return false; 404 } 405 } 406 } 407 408 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 409 !isa<ImplicitParamDecl>(D) && 410 D->getDeclContext()->isFunctionOrMethod()); 411} 412 413void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 414 if (S->decl_empty()) return; 415 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 416 "Scope shouldn't contain decls!"); 417 418 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 419 I != E; ++I) { 420 Decl *TmpD = (*I).getAs<Decl>(); 421 assert(TmpD && "This decl didn't get pushed??"); 422 423 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 424 NamedDecl *D = cast<NamedDecl>(TmpD); 425 426 if (!D->getDeclName()) continue; 427 428 // Diagnose unused variables in this scope. 429 if (ShouldDiagnoseUnusedDecl(D)) 430 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 431 432 // Remove this name from our lexical scope. 433 IdResolver.RemoveDecl(D); 434 } 435} 436 437/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 438/// return 0 if one not found. 439ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 440 // The third "scope" argument is 0 since we aren't enabling lazy built-in 441 // creation from this context. 442 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 443 444 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 445} 446 447/// getNonFieldDeclScope - Retrieves the innermost scope, starting 448/// from S, where a non-field would be declared. This routine copes 449/// with the difference between C and C++ scoping rules in structs and 450/// unions. For example, the following code is well-formed in C but 451/// ill-formed in C++: 452/// @code 453/// struct S6 { 454/// enum { BAR } e; 455/// }; 456/// 457/// void test_S6() { 458/// struct S6 a; 459/// a.e = BAR; 460/// } 461/// @endcode 462/// For the declaration of BAR, this routine will return a different 463/// scope. The scope S will be the scope of the unnamed enumeration 464/// within S6. In C++, this routine will return the scope associated 465/// with S6, because the enumeration's scope is a transparent 466/// context but structures can contain non-field names. In C, this 467/// routine will return the translation unit scope, since the 468/// enumeration's scope is a transparent context and structures cannot 469/// contain non-field names. 470Scope *Sema::getNonFieldDeclScope(Scope *S) { 471 while (((S->getFlags() & Scope::DeclScope) == 0) || 472 (S->getEntity() && 473 ((DeclContext *)S->getEntity())->isTransparentContext()) || 474 (S->isClassScope() && !getLangOptions().CPlusPlus)) 475 S = S->getParent(); 476 return S; 477} 478 479void Sema::InitBuiltinVaListType() { 480 if (!Context.getBuiltinVaListType().isNull()) 481 return; 482 483 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 484 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 485 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 486 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 487} 488 489/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 490/// file scope. lazily create a decl for it. ForRedeclaration is true 491/// if we're creating this built-in in anticipation of redeclaring the 492/// built-in. 493NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 494 Scope *S, bool ForRedeclaration, 495 SourceLocation Loc) { 496 Builtin::ID BID = (Builtin::ID)bid; 497 498 if (Context.BuiltinInfo.hasVAListUse(BID)) 499 InitBuiltinVaListType(); 500 501 ASTContext::GetBuiltinTypeError Error; 502 QualType R = Context.GetBuiltinType(BID, Error); 503 switch (Error) { 504 case ASTContext::GE_None: 505 // Okay 506 break; 507 508 case ASTContext::GE_Missing_stdio: 509 if (ForRedeclaration) 510 Diag(Loc, diag::err_implicit_decl_requires_stdio) 511 << Context.BuiltinInfo.GetName(BID); 512 return 0; 513 514 case ASTContext::GE_Missing_setjmp: 515 if (ForRedeclaration) 516 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 517 << Context.BuiltinInfo.GetName(BID); 518 return 0; 519 } 520 521 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 522 Diag(Loc, diag::ext_implicit_lib_function_decl) 523 << Context.BuiltinInfo.GetName(BID) 524 << R; 525 if (Context.BuiltinInfo.getHeaderName(BID) && 526 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 527 != Diagnostic::Ignored) 528 Diag(Loc, diag::note_please_include_header) 529 << Context.BuiltinInfo.getHeaderName(BID) 530 << Context.BuiltinInfo.GetName(BID); 531 } 532 533 FunctionDecl *New = FunctionDecl::Create(Context, 534 Context.getTranslationUnitDecl(), 535 Loc, II, R, /*DInfo=*/0, 536 FunctionDecl::Extern, false, 537 /*hasPrototype=*/true); 538 New->setImplicit(); 539 540 // Create Decl objects for each parameter, adding them to the 541 // FunctionDecl. 542 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 543 llvm::SmallVector<ParmVarDecl*, 16> Params; 544 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 545 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 546 FT->getArgType(i), /*DInfo=*/0, 547 VarDecl::None, 0)); 548 New->setParams(Context, Params.data(), Params.size()); 549 } 550 551 AddKnownFunctionAttributes(New); 552 553 // TUScope is the translation-unit scope to insert this function into. 554 // FIXME: This is hideous. We need to teach PushOnScopeChains to 555 // relate Scopes to DeclContexts, and probably eliminate CurContext 556 // entirely, but we're not there yet. 557 DeclContext *SavedContext = CurContext; 558 CurContext = Context.getTranslationUnitDecl(); 559 PushOnScopeChains(New, TUScope); 560 CurContext = SavedContext; 561 return New; 562} 563 564/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 565/// same name and scope as a previous declaration 'Old'. Figure out 566/// how to resolve this situation, merging decls or emitting 567/// diagnostics as appropriate. If there was an error, set New to be invalid. 568/// 569void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 570 // If either decl is known invalid already, set the new one to be invalid and 571 // don't bother doing any merging checks. 572 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 573 return New->setInvalidDecl(); 574 575 // Allow multiple definitions for ObjC built-in typedefs. 576 // FIXME: Verify the underlying types are equivalent! 577 if (getLangOptions().ObjC1) { 578 const IdentifierInfo *TypeID = New->getIdentifier(); 579 switch (TypeID->getLength()) { 580 default: break; 581 case 2: 582 if (!TypeID->isStr("id")) 583 break; 584 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 585 // Install the built-in type for 'id', ignoring the current definition. 586 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 587 return; 588 case 5: 589 if (!TypeID->isStr("Class")) 590 break; 591 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 592 // Install the built-in type for 'Class', ignoring the current definition. 593 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 594 return; 595 case 3: 596 if (!TypeID->isStr("SEL")) 597 break; 598 Context.setObjCSelType(Context.getTypeDeclType(New)); 599 return; 600 case 8: 601 if (!TypeID->isStr("Protocol")) 602 break; 603 Context.setObjCProtoType(New->getUnderlyingType()); 604 return; 605 } 606 // Fall through - the typedef name was not a builtin type. 607 } 608 // Verify the old decl was also a type. 609 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 610 if (!Old) { 611 Diag(New->getLocation(), diag::err_redefinition_different_kind) 612 << New->getDeclName(); 613 if (OldD->getLocation().isValid()) 614 Diag(OldD->getLocation(), diag::note_previous_definition); 615 return New->setInvalidDecl(); 616 } 617 618 // Determine the "old" type we'll use for checking and diagnostics. 619 QualType OldType; 620 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 621 OldType = OldTypedef->getUnderlyingType(); 622 else 623 OldType = Context.getTypeDeclType(Old); 624 625 // If the typedef types are not identical, reject them in all languages and 626 // with any extensions enabled. 627 628 if (OldType != New->getUnderlyingType() && 629 Context.getCanonicalType(OldType) != 630 Context.getCanonicalType(New->getUnderlyingType())) { 631 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 632 << New->getUnderlyingType() << OldType; 633 if (Old->getLocation().isValid()) 634 Diag(Old->getLocation(), diag::note_previous_definition); 635 return New->setInvalidDecl(); 636 } 637 638 if (getLangOptions().Microsoft) 639 return; 640 641 // C++ [dcl.typedef]p2: 642 // In a given non-class scope, a typedef specifier can be used to 643 // redefine the name of any type declared in that scope to refer 644 // to the type to which it already refers. 645 if (getLangOptions().CPlusPlus) { 646 if (!isa<CXXRecordDecl>(CurContext)) 647 return; 648 Diag(New->getLocation(), diag::err_redefinition) 649 << New->getDeclName(); 650 Diag(Old->getLocation(), diag::note_previous_definition); 651 return New->setInvalidDecl(); 652 } 653 654 // If we have a redefinition of a typedef in C, emit a warning. This warning 655 // is normally mapped to an error, but can be controlled with 656 // -Wtypedef-redefinition. If either the original or the redefinition is 657 // in a system header, don't emit this for compatibility with GCC. 658 if (PP.getDiagnostics().getSuppressSystemWarnings() && 659 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 660 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 661 return; 662 663 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 664 << New->getDeclName(); 665 Diag(Old->getLocation(), diag::note_previous_definition); 666 return; 667} 668 669/// DeclhasAttr - returns true if decl Declaration already has the target 670/// attribute. 671static bool 672DeclHasAttr(const Decl *decl, const Attr *target) { 673 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 674 if (attr->getKind() == target->getKind()) 675 return true; 676 677 return false; 678} 679 680/// MergeAttributes - append attributes from the Old decl to the New one. 681static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 682 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 683 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 684 Attr *NewAttr = attr->clone(C); 685 NewAttr->setInherited(true); 686 New->addAttr(NewAttr); 687 } 688 } 689} 690 691/// Used in MergeFunctionDecl to keep track of function parameters in 692/// C. 693struct GNUCompatibleParamWarning { 694 ParmVarDecl *OldParm; 695 ParmVarDecl *NewParm; 696 QualType PromotedType; 697}; 698 699/// MergeFunctionDecl - We just parsed a function 'New' from 700/// declarator D which has the same name and scope as a previous 701/// declaration 'Old'. Figure out how to resolve this situation, 702/// merging decls or emitting diagnostics as appropriate. 703/// 704/// In C++, New and Old must be declarations that are not 705/// overloaded. Use IsOverload to determine whether New and Old are 706/// overloaded, and to select the Old declaration that New should be 707/// merged with. 708/// 709/// Returns true if there was an error, false otherwise. 710bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 711 assert(!isa<OverloadedFunctionDecl>(OldD) && 712 "Cannot merge with an overloaded function declaration"); 713 714 // Verify the old decl was also a function. 715 FunctionDecl *Old = 0; 716 if (FunctionTemplateDecl *OldFunctionTemplate 717 = dyn_cast<FunctionTemplateDecl>(OldD)) 718 Old = OldFunctionTemplate->getTemplatedDecl(); 719 else 720 Old = dyn_cast<FunctionDecl>(OldD); 721 if (!Old) { 722 Diag(New->getLocation(), diag::err_redefinition_different_kind) 723 << New->getDeclName(); 724 Diag(OldD->getLocation(), diag::note_previous_definition); 725 return true; 726 } 727 728 // Determine whether the previous declaration was a definition, 729 // implicit declaration, or a declaration. 730 diag::kind PrevDiag; 731 if (Old->isThisDeclarationADefinition()) 732 PrevDiag = diag::note_previous_definition; 733 else if (Old->isImplicit()) 734 PrevDiag = diag::note_previous_implicit_declaration; 735 else 736 PrevDiag = diag::note_previous_declaration; 737 738 QualType OldQType = Context.getCanonicalType(Old->getType()); 739 QualType NewQType = Context.getCanonicalType(New->getType()); 740 741 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 742 New->getStorageClass() == FunctionDecl::Static && 743 Old->getStorageClass() != FunctionDecl::Static) { 744 Diag(New->getLocation(), diag::err_static_non_static) 745 << New; 746 Diag(Old->getLocation(), PrevDiag); 747 return true; 748 } 749 750 if (getLangOptions().CPlusPlus) { 751 // (C++98 13.1p2): 752 // Certain function declarations cannot be overloaded: 753 // -- Function declarations that differ only in the return type 754 // cannot be overloaded. 755 QualType OldReturnType 756 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 757 QualType NewReturnType 758 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 759 if (OldReturnType != NewReturnType) { 760 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 761 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 762 return true; 763 } 764 765 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 766 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 767 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 768 NewMethod->getLexicalDeclContext()->isRecord()) { 769 // -- Member function declarations with the same name and the 770 // same parameter types cannot be overloaded if any of them 771 // is a static member function declaration. 772 if (OldMethod->isStatic() || NewMethod->isStatic()) { 773 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 774 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 775 return true; 776 } 777 778 // C++ [class.mem]p1: 779 // [...] A member shall not be declared twice in the 780 // member-specification, except that a nested class or member 781 // class template can be declared and then later defined. 782 unsigned NewDiag; 783 if (isa<CXXConstructorDecl>(OldMethod)) 784 NewDiag = diag::err_constructor_redeclared; 785 else if (isa<CXXDestructorDecl>(NewMethod)) 786 NewDiag = diag::err_destructor_redeclared; 787 else if (isa<CXXConversionDecl>(NewMethod)) 788 NewDiag = diag::err_conv_function_redeclared; 789 else 790 NewDiag = diag::err_member_redeclared; 791 792 Diag(New->getLocation(), NewDiag); 793 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 794 } 795 796 // (C++98 8.3.5p3): 797 // All declarations for a function shall agree exactly in both the 798 // return type and the parameter-type-list. 799 if (OldQType == NewQType) 800 return MergeCompatibleFunctionDecls(New, Old); 801 802 // Fall through for conflicting redeclarations and redefinitions. 803 } 804 805 // C: Function types need to be compatible, not identical. This handles 806 // duplicate function decls like "void f(int); void f(enum X);" properly. 807 if (!getLangOptions().CPlusPlus && 808 Context.typesAreCompatible(OldQType, NewQType)) { 809 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 810 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 811 const FunctionProtoType *OldProto = 0; 812 if (isa<FunctionNoProtoType>(NewFuncType) && 813 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 814 // The old declaration provided a function prototype, but the 815 // new declaration does not. Merge in the prototype. 816 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 817 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 818 OldProto->arg_type_end()); 819 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 820 ParamTypes.data(), ParamTypes.size(), 821 OldProto->isVariadic(), 822 OldProto->getTypeQuals()); 823 New->setType(NewQType); 824 New->setHasInheritedPrototype(); 825 826 // Synthesize a parameter for each argument type. 827 llvm::SmallVector<ParmVarDecl*, 16> Params; 828 for (FunctionProtoType::arg_type_iterator 829 ParamType = OldProto->arg_type_begin(), 830 ParamEnd = OldProto->arg_type_end(); 831 ParamType != ParamEnd; ++ParamType) { 832 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 833 SourceLocation(), 0, 834 *ParamType, /*DInfo=*/0, 835 VarDecl::None, 0); 836 Param->setImplicit(); 837 Params.push_back(Param); 838 } 839 840 New->setParams(Context, Params.data(), Params.size()); 841 } 842 843 return MergeCompatibleFunctionDecls(New, Old); 844 } 845 846 // GNU C permits a K&R definition to follow a prototype declaration 847 // if the declared types of the parameters in the K&R definition 848 // match the types in the prototype declaration, even when the 849 // promoted types of the parameters from the K&R definition differ 850 // from the types in the prototype. GCC then keeps the types from 851 // the prototype. 852 // 853 // If a variadic prototype is followed by a non-variadic K&R definition, 854 // the K&R definition becomes variadic. This is sort of an edge case, but 855 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 856 // C99 6.9.1p8. 857 if (!getLangOptions().CPlusPlus && 858 Old->hasPrototype() && !New->hasPrototype() && 859 New->getType()->getAs<FunctionProtoType>() && 860 Old->getNumParams() == New->getNumParams()) { 861 llvm::SmallVector<QualType, 16> ArgTypes; 862 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 863 const FunctionProtoType *OldProto 864 = Old->getType()->getAs<FunctionProtoType>(); 865 const FunctionProtoType *NewProto 866 = New->getType()->getAs<FunctionProtoType>(); 867 868 // Determine whether this is the GNU C extension. 869 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 870 NewProto->getResultType()); 871 bool LooseCompatible = !MergedReturn.isNull(); 872 for (unsigned Idx = 0, End = Old->getNumParams(); 873 LooseCompatible && Idx != End; ++Idx) { 874 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 875 ParmVarDecl *NewParm = New->getParamDecl(Idx); 876 if (Context.typesAreCompatible(OldParm->getType(), 877 NewProto->getArgType(Idx))) { 878 ArgTypes.push_back(NewParm->getType()); 879 } else if (Context.typesAreCompatible(OldParm->getType(), 880 NewParm->getType())) { 881 GNUCompatibleParamWarning Warn 882 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 883 Warnings.push_back(Warn); 884 ArgTypes.push_back(NewParm->getType()); 885 } else 886 LooseCompatible = false; 887 } 888 889 if (LooseCompatible) { 890 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 891 Diag(Warnings[Warn].NewParm->getLocation(), 892 diag::ext_param_promoted_not_compatible_with_prototype) 893 << Warnings[Warn].PromotedType 894 << Warnings[Warn].OldParm->getType(); 895 Diag(Warnings[Warn].OldParm->getLocation(), 896 diag::note_previous_declaration); 897 } 898 899 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 900 ArgTypes.size(), 901 OldProto->isVariadic(), 0)); 902 return MergeCompatibleFunctionDecls(New, Old); 903 } 904 905 // Fall through to diagnose conflicting types. 906 } 907 908 // A function that has already been declared has been redeclared or defined 909 // with a different type- show appropriate diagnostic 910 if (unsigned BuiltinID = Old->getBuiltinID()) { 911 // The user has declared a builtin function with an incompatible 912 // signature. 913 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 914 // The function the user is redeclaring is a library-defined 915 // function like 'malloc' or 'printf'. Warn about the 916 // redeclaration, then pretend that we don't know about this 917 // library built-in. 918 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 919 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 920 << Old << Old->getType(); 921 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 922 Old->setInvalidDecl(); 923 return false; 924 } 925 926 PrevDiag = diag::note_previous_builtin_declaration; 927 } 928 929 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 930 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 931 return true; 932} 933 934/// \brief Completes the merge of two function declarations that are 935/// known to be compatible. 936/// 937/// This routine handles the merging of attributes and other 938/// properties of function declarations form the old declaration to 939/// the new declaration, once we know that New is in fact a 940/// redeclaration of Old. 941/// 942/// \returns false 943bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 944 // Merge the attributes 945 MergeAttributes(New, Old, Context); 946 947 // Merge the storage class. 948 if (Old->getStorageClass() != FunctionDecl::Extern && 949 Old->getStorageClass() != FunctionDecl::None) 950 New->setStorageClass(Old->getStorageClass()); 951 952 // Merge "pure" flag. 953 if (Old->isPure()) 954 New->setPure(); 955 956 // Merge the "deleted" flag. 957 if (Old->isDeleted()) 958 New->setDeleted(); 959 960 if (getLangOptions().CPlusPlus) 961 return MergeCXXFunctionDecl(New, Old); 962 963 return false; 964} 965 966/// MergeVarDecl - We just parsed a variable 'New' which has the same name 967/// and scope as a previous declaration 'Old'. Figure out how to resolve this 968/// situation, merging decls or emitting diagnostics as appropriate. 969/// 970/// Tentative definition rules (C99 6.9.2p2) are checked by 971/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 972/// definitions here, since the initializer hasn't been attached. 973/// 974void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 975 // If either decl is invalid, make sure the new one is marked invalid and 976 // don't do any other checking. 977 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 978 return New->setInvalidDecl(); 979 980 // Verify the old decl was also a variable. 981 VarDecl *Old = dyn_cast<VarDecl>(OldD); 982 if (!Old) { 983 Diag(New->getLocation(), diag::err_redefinition_different_kind) 984 << New->getDeclName(); 985 Diag(OldD->getLocation(), diag::note_previous_definition); 986 return New->setInvalidDecl(); 987 } 988 989 MergeAttributes(New, Old, Context); 990 991 // Merge the types 992 QualType MergedT; 993 if (getLangOptions().CPlusPlus) { 994 if (Context.hasSameType(New->getType(), Old->getType())) 995 MergedT = New->getType(); 996 // C++ [basic.types]p7: 997 // [...] The declared type of an array object might be an array of 998 // unknown size and therefore be incomplete at one point in a 999 // translation unit and complete later on; [...] 1000 else if (Old->getType()->isIncompleteArrayType() && 1001 New->getType()->isArrayType()) { 1002 CanQual<ArrayType> OldArray 1003 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1004 CanQual<ArrayType> NewArray 1005 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1006 if (OldArray->getElementType() == NewArray->getElementType()) 1007 MergedT = New->getType(); 1008 } 1009 } else { 1010 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1011 } 1012 if (MergedT.isNull()) { 1013 Diag(New->getLocation(), diag::err_redefinition_different_type) 1014 << New->getDeclName(); 1015 Diag(Old->getLocation(), diag::note_previous_definition); 1016 return New->setInvalidDecl(); 1017 } 1018 New->setType(MergedT); 1019 1020 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1021 if (New->getStorageClass() == VarDecl::Static && 1022 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1023 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1024 Diag(Old->getLocation(), diag::note_previous_definition); 1025 return New->setInvalidDecl(); 1026 } 1027 // C99 6.2.2p4: 1028 // For an identifier declared with the storage-class specifier 1029 // extern in a scope in which a prior declaration of that 1030 // identifier is visible,23) if the prior declaration specifies 1031 // internal or external linkage, the linkage of the identifier at 1032 // the later declaration is the same as the linkage specified at 1033 // the prior declaration. If no prior declaration is visible, or 1034 // if the prior declaration specifies no linkage, then the 1035 // identifier has external linkage. 1036 if (New->hasExternalStorage() && Old->hasLinkage()) 1037 /* Okay */; 1038 else if (New->getStorageClass() != VarDecl::Static && 1039 Old->getStorageClass() == VarDecl::Static) { 1040 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1041 Diag(Old->getLocation(), diag::note_previous_definition); 1042 return New->setInvalidDecl(); 1043 } 1044 1045 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1046 1047 // FIXME: The test for external storage here seems wrong? We still 1048 // need to check for mismatches. 1049 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1050 // Don't complain about out-of-line definitions of static members. 1051 !(Old->getLexicalDeclContext()->isRecord() && 1052 !New->getLexicalDeclContext()->isRecord())) { 1053 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1054 Diag(Old->getLocation(), diag::note_previous_definition); 1055 return New->setInvalidDecl(); 1056 } 1057 1058 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1059 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1060 Diag(Old->getLocation(), diag::note_previous_definition); 1061 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1062 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1063 Diag(Old->getLocation(), diag::note_previous_definition); 1064 } 1065 1066 // Keep a chain of previous declarations. 1067 New->setPreviousDeclaration(Old); 1068} 1069 1070/// CheckFallThrough - Check that we don't fall off the end of a 1071/// Statement that should return a value. 1072/// 1073/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1074/// MaybeFallThrough iff we might or might not fall off the end, 1075/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1076/// return. We assume NeverFallThrough iff we never fall off the end of the 1077/// statement but we may return. We assume that functions not marked noreturn 1078/// will return. 1079Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1080 // FIXME: Eventually share this CFG object when we have other warnings based 1081 // of the CFG. This can be done using AnalysisContext. 1082 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1083 1084 // FIXME: They should never return 0, fix that, delete this code. 1085 if (cfg == 0) 1086 // FIXME: This should be NeverFallThrough 1087 return NeverFallThroughOrReturn; 1088 // The CFG leaves in dead things, and we don't want to dead code paths to 1089 // confuse us, so we mark all live things first. 1090 std::queue<CFGBlock*> workq; 1091 llvm::BitVector live(cfg->getNumBlockIDs()); 1092 // Prep work queue 1093 workq.push(&cfg->getEntry()); 1094 // Solve 1095 while (!workq.empty()) { 1096 CFGBlock *item = workq.front(); 1097 workq.pop(); 1098 live.set(item->getBlockID()); 1099 for (CFGBlock::succ_iterator I=item->succ_begin(), 1100 E=item->succ_end(); 1101 I != E; 1102 ++I) { 1103 if ((*I) && !live[(*I)->getBlockID()]) { 1104 live.set((*I)->getBlockID()); 1105 workq.push(*I); 1106 } 1107 } 1108 } 1109 1110 // Now we know what is live, we check the live precessors of the exit block 1111 // and look for fall through paths, being careful to ignore normal returns, 1112 // and exceptional paths. 1113 bool HasLiveReturn = false; 1114 bool HasFakeEdge = false; 1115 bool HasPlainEdge = false; 1116 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1117 E = cfg->getExit().pred_end(); 1118 I != E; 1119 ++I) { 1120 CFGBlock& B = **I; 1121 if (!live[B.getBlockID()]) 1122 continue; 1123 if (B.size() == 0) { 1124 // A labeled empty statement, or the entry block... 1125 HasPlainEdge = true; 1126 continue; 1127 } 1128 Stmt *S = B[B.size()-1]; 1129 if (isa<ReturnStmt>(S)) { 1130 HasLiveReturn = true; 1131 continue; 1132 } 1133 if (isa<ObjCAtThrowStmt>(S)) { 1134 HasFakeEdge = true; 1135 continue; 1136 } 1137 if (isa<CXXThrowExpr>(S)) { 1138 HasFakeEdge = true; 1139 continue; 1140 } 1141 bool NoReturnEdge = false; 1142 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1143 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1144 if (CEE->getType().getNoReturnAttr()) { 1145 NoReturnEdge = true; 1146 HasFakeEdge = true; 1147 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1148 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1149 if (FD->hasAttr<NoReturnAttr>()) { 1150 NoReturnEdge = true; 1151 HasFakeEdge = true; 1152 } 1153 } 1154 } 1155 } 1156 // FIXME: Add noreturn message sends. 1157 if (NoReturnEdge == false) 1158 HasPlainEdge = true; 1159 } 1160 if (!HasPlainEdge) { 1161 if (HasLiveReturn) 1162 return NeverFallThrough; 1163 return NeverFallThroughOrReturn; 1164 } 1165 if (HasFakeEdge || HasLiveReturn) 1166 return MaybeFallThrough; 1167 // This says AlwaysFallThrough for calls to functions that are not marked 1168 // noreturn, that don't return. If people would like this warning to be more 1169 // accurate, such functions should be marked as noreturn. 1170 return AlwaysFallThrough; 1171} 1172 1173/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1174/// function that should return a value. Check that we don't fall off the end 1175/// of a noreturn function. We assume that functions and blocks not marked 1176/// noreturn will return. 1177void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1178 // FIXME: Would be nice if we had a better way to control cascading errors, 1179 // but for now, avoid them. The problem is that when Parse sees: 1180 // int foo() { return a; } 1181 // The return is eaten and the Sema code sees just: 1182 // int foo() { } 1183 // which this code would then warn about. 1184 if (getDiagnostics().hasErrorOccurred()) 1185 return; 1186 1187 bool ReturnsVoid = false; 1188 bool HasNoReturn = false; 1189 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1190 // If the result type of the function is a dependent type, we don't know 1191 // whether it will be void or not, so don't 1192 if (FD->getResultType()->isDependentType()) 1193 return; 1194 if (FD->getResultType()->isVoidType()) 1195 ReturnsVoid = true; 1196 if (FD->hasAttr<NoReturnAttr>()) 1197 HasNoReturn = true; 1198 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1199 if (MD->getResultType()->isVoidType()) 1200 ReturnsVoid = true; 1201 if (MD->hasAttr<NoReturnAttr>()) 1202 HasNoReturn = true; 1203 } 1204 1205 // Short circuit for compilation speed. 1206 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1207 == Diagnostic::Ignored || ReturnsVoid) 1208 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1209 == Diagnostic::Ignored || !HasNoReturn) 1210 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1211 == Diagnostic::Ignored || !ReturnsVoid)) 1212 return; 1213 // FIXME: Function try block 1214 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1215 switch (CheckFallThrough(Body)) { 1216 case MaybeFallThrough: 1217 if (HasNoReturn) 1218 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1219 else if (!ReturnsVoid) 1220 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1221 break; 1222 case AlwaysFallThrough: 1223 if (HasNoReturn) 1224 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1225 else if (!ReturnsVoid) 1226 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1227 break; 1228 case NeverFallThroughOrReturn: 1229 if (ReturnsVoid && !HasNoReturn) 1230 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1231 break; 1232 case NeverFallThrough: 1233 break; 1234 } 1235 } 1236} 1237 1238/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1239/// that should return a value. Check that we don't fall off the end of a 1240/// noreturn block. We assume that functions and blocks not marked noreturn 1241/// will return. 1242void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1243 // FIXME: Would be nice if we had a better way to control cascading errors, 1244 // but for now, avoid them. The problem is that when Parse sees: 1245 // int foo() { return a; } 1246 // The return is eaten and the Sema code sees just: 1247 // int foo() { } 1248 // which this code would then warn about. 1249 if (getDiagnostics().hasErrorOccurred()) 1250 return; 1251 bool ReturnsVoid = false; 1252 bool HasNoReturn = false; 1253 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1254 if (FT->getResultType()->isVoidType()) 1255 ReturnsVoid = true; 1256 if (FT->getNoReturnAttr()) 1257 HasNoReturn = true; 1258 } 1259 1260 // Short circuit for compilation speed. 1261 if (ReturnsVoid 1262 && !HasNoReturn 1263 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1264 == Diagnostic::Ignored || !ReturnsVoid)) 1265 return; 1266 // FIXME: Funtion try block 1267 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1268 switch (CheckFallThrough(Body)) { 1269 case MaybeFallThrough: 1270 if (HasNoReturn) 1271 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1272 else if (!ReturnsVoid) 1273 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1274 break; 1275 case AlwaysFallThrough: 1276 if (HasNoReturn) 1277 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1278 else if (!ReturnsVoid) 1279 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1280 break; 1281 case NeverFallThroughOrReturn: 1282 if (ReturnsVoid) 1283 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1284 break; 1285 case NeverFallThrough: 1286 break; 1287 } 1288 } 1289} 1290 1291/// CheckParmsForFunctionDef - Check that the parameters of the given 1292/// function are appropriate for the definition of a function. This 1293/// takes care of any checks that cannot be performed on the 1294/// declaration itself, e.g., that the types of each of the function 1295/// parameters are complete. 1296bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1297 bool HasInvalidParm = false; 1298 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1299 ParmVarDecl *Param = FD->getParamDecl(p); 1300 1301 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1302 // function declarator that is part of a function definition of 1303 // that function shall not have incomplete type. 1304 // 1305 // This is also C++ [dcl.fct]p6. 1306 if (!Param->isInvalidDecl() && 1307 RequireCompleteType(Param->getLocation(), Param->getType(), 1308 diag::err_typecheck_decl_incomplete_type)) { 1309 Param->setInvalidDecl(); 1310 HasInvalidParm = true; 1311 } 1312 1313 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1314 // declaration of each parameter shall include an identifier. 1315 if (Param->getIdentifier() == 0 && 1316 !Param->isImplicit() && 1317 !getLangOptions().CPlusPlus) 1318 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1319 } 1320 1321 return HasInvalidParm; 1322} 1323 1324/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1325/// no declarator (e.g. "struct foo;") is parsed. 1326Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1327 // FIXME: Error on auto/register at file scope 1328 // FIXME: Error on inline/virtual/explicit 1329 // FIXME: Error on invalid restrict 1330 // FIXME: Warn on useless __thread 1331 // FIXME: Warn on useless const/volatile 1332 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1333 // FIXME: Warn on useless attributes 1334 Decl *TagD = 0; 1335 TagDecl *Tag = 0; 1336 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1337 DS.getTypeSpecType() == DeclSpec::TST_struct || 1338 DS.getTypeSpecType() == DeclSpec::TST_union || 1339 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1340 TagD = static_cast<Decl *>(DS.getTypeRep()); 1341 1342 if (!TagD) // We probably had an error 1343 return DeclPtrTy(); 1344 1345 // Note that the above type specs guarantee that the 1346 // type rep is a Decl, whereas in many of the others 1347 // it's a Type. 1348 Tag = dyn_cast<TagDecl>(TagD); 1349 } 1350 1351 if (DS.isFriendSpecified()) { 1352 // If we're dealing with a class template decl, assume that the 1353 // template routines are handling it. 1354 if (TagD && isa<ClassTemplateDecl>(TagD)) 1355 return DeclPtrTy(); 1356 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1357 } 1358 1359 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1360 // If there are attributes in the DeclSpec, apply them to the record. 1361 if (const AttributeList *AL = DS.getAttributes()) 1362 ProcessDeclAttributeList(S, Record, AL); 1363 1364 if (!Record->getDeclName() && Record->isDefinition() && 1365 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1366 if (getLangOptions().CPlusPlus || 1367 Record->getDeclContext()->isRecord()) 1368 return BuildAnonymousStructOrUnion(S, DS, Record); 1369 1370 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1371 << DS.getSourceRange(); 1372 } 1373 1374 // Microsoft allows unnamed struct/union fields. Don't complain 1375 // about them. 1376 // FIXME: Should we support Microsoft's extensions in this area? 1377 if (Record->getDeclName() && getLangOptions().Microsoft) 1378 return DeclPtrTy::make(Tag); 1379 } 1380 1381 if (!DS.isMissingDeclaratorOk() && 1382 DS.getTypeSpecType() != DeclSpec::TST_error) { 1383 // Warn about typedefs of enums without names, since this is an 1384 // extension in both Microsoft an GNU. 1385 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1386 Tag && isa<EnumDecl>(Tag)) { 1387 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1388 << DS.getSourceRange(); 1389 return DeclPtrTy::make(Tag); 1390 } 1391 1392 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1393 << DS.getSourceRange(); 1394 return DeclPtrTy(); 1395 } 1396 1397 return DeclPtrTy::make(Tag); 1398} 1399 1400/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1401/// anonymous struct or union AnonRecord into the owning context Owner 1402/// and scope S. This routine will be invoked just after we realize 1403/// that an unnamed union or struct is actually an anonymous union or 1404/// struct, e.g., 1405/// 1406/// @code 1407/// union { 1408/// int i; 1409/// float f; 1410/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1411/// // f into the surrounding scope.x 1412/// @endcode 1413/// 1414/// This routine is recursive, injecting the names of nested anonymous 1415/// structs/unions into the owning context and scope as well. 1416bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1417 RecordDecl *AnonRecord) { 1418 bool Invalid = false; 1419 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1420 FEnd = AnonRecord->field_end(); 1421 F != FEnd; ++F) { 1422 if ((*F)->getDeclName()) { 1423 LookupResult R(*this, (*F)->getDeclName(), SourceLocation(), 1424 LookupOrdinaryName, LookupResult::ForRedeclaration); 1425 LookupQualifiedName(R, Owner); 1426 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1427 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1428 // C++ [class.union]p2: 1429 // The names of the members of an anonymous union shall be 1430 // distinct from the names of any other entity in the 1431 // scope in which the anonymous union is declared. 1432 unsigned diagKind 1433 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1434 : diag::err_anonymous_struct_member_redecl; 1435 Diag((*F)->getLocation(), diagKind) 1436 << (*F)->getDeclName(); 1437 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1438 Invalid = true; 1439 } else { 1440 // C++ [class.union]p2: 1441 // For the purpose of name lookup, after the anonymous union 1442 // definition, the members of the anonymous union are 1443 // considered to have been defined in the scope in which the 1444 // anonymous union is declared. 1445 Owner->makeDeclVisibleInContext(*F); 1446 S->AddDecl(DeclPtrTy::make(*F)); 1447 IdResolver.AddDecl(*F); 1448 } 1449 } else if (const RecordType *InnerRecordType 1450 = (*F)->getType()->getAs<RecordType>()) { 1451 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1452 if (InnerRecord->isAnonymousStructOrUnion()) 1453 Invalid = Invalid || 1454 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1455 } 1456 } 1457 1458 return Invalid; 1459} 1460 1461/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1462/// anonymous structure or union. Anonymous unions are a C++ feature 1463/// (C++ [class.union]) and a GNU C extension; anonymous structures 1464/// are a GNU C and GNU C++ extension. 1465Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1466 RecordDecl *Record) { 1467 DeclContext *Owner = Record->getDeclContext(); 1468 1469 // Diagnose whether this anonymous struct/union is an extension. 1470 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1471 Diag(Record->getLocation(), diag::ext_anonymous_union); 1472 else if (!Record->isUnion()) 1473 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1474 1475 // C and C++ require different kinds of checks for anonymous 1476 // structs/unions. 1477 bool Invalid = false; 1478 if (getLangOptions().CPlusPlus) { 1479 const char* PrevSpec = 0; 1480 unsigned DiagID; 1481 // C++ [class.union]p3: 1482 // Anonymous unions declared in a named namespace or in the 1483 // global namespace shall be declared static. 1484 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1485 (isa<TranslationUnitDecl>(Owner) || 1486 (isa<NamespaceDecl>(Owner) && 1487 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1488 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1489 Invalid = true; 1490 1491 // Recover by adding 'static'. 1492 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1493 PrevSpec, DiagID); 1494 } 1495 // C++ [class.union]p3: 1496 // A storage class is not allowed in a declaration of an 1497 // anonymous union in a class scope. 1498 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1499 isa<RecordDecl>(Owner)) { 1500 Diag(DS.getStorageClassSpecLoc(), 1501 diag::err_anonymous_union_with_storage_spec); 1502 Invalid = true; 1503 1504 // Recover by removing the storage specifier. 1505 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1506 PrevSpec, DiagID); 1507 } 1508 1509 // C++ [class.union]p2: 1510 // The member-specification of an anonymous union shall only 1511 // define non-static data members. [Note: nested types and 1512 // functions cannot be declared within an anonymous union. ] 1513 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1514 MemEnd = Record->decls_end(); 1515 Mem != MemEnd; ++Mem) { 1516 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1517 // C++ [class.union]p3: 1518 // An anonymous union shall not have private or protected 1519 // members (clause 11). 1520 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1521 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1522 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1523 Invalid = true; 1524 } 1525 } else if ((*Mem)->isImplicit()) { 1526 // Any implicit members are fine. 1527 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1528 // This is a type that showed up in an 1529 // elaborated-type-specifier inside the anonymous struct or 1530 // union, but which actually declares a type outside of the 1531 // anonymous struct or union. It's okay. 1532 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1533 if (!MemRecord->isAnonymousStructOrUnion() && 1534 MemRecord->getDeclName()) { 1535 // This is a nested type declaration. 1536 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1537 << (int)Record->isUnion(); 1538 Invalid = true; 1539 } 1540 } else { 1541 // We have something that isn't a non-static data 1542 // member. Complain about it. 1543 unsigned DK = diag::err_anonymous_record_bad_member; 1544 if (isa<TypeDecl>(*Mem)) 1545 DK = diag::err_anonymous_record_with_type; 1546 else if (isa<FunctionDecl>(*Mem)) 1547 DK = diag::err_anonymous_record_with_function; 1548 else if (isa<VarDecl>(*Mem)) 1549 DK = diag::err_anonymous_record_with_static; 1550 Diag((*Mem)->getLocation(), DK) 1551 << (int)Record->isUnion(); 1552 Invalid = true; 1553 } 1554 } 1555 } 1556 1557 if (!Record->isUnion() && !Owner->isRecord()) { 1558 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1559 << (int)getLangOptions().CPlusPlus; 1560 Invalid = true; 1561 } 1562 1563 // Mock up a declarator. 1564 Declarator Dc(DS, Declarator::TypeNameContext); 1565 DeclaratorInfo *DInfo = 0; 1566 GetTypeForDeclarator(Dc, S, &DInfo); 1567 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1568 1569 // Create a declaration for this anonymous struct/union. 1570 NamedDecl *Anon = 0; 1571 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1572 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1573 /*IdentifierInfo=*/0, 1574 Context.getTypeDeclType(Record), 1575 DInfo, 1576 /*BitWidth=*/0, /*Mutable=*/false); 1577 Anon->setAccess(AS_public); 1578 if (getLangOptions().CPlusPlus) 1579 FieldCollector->Add(cast<FieldDecl>(Anon)); 1580 } else { 1581 VarDecl::StorageClass SC; 1582 switch (DS.getStorageClassSpec()) { 1583 default: assert(0 && "Unknown storage class!"); 1584 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1585 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1586 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1587 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1588 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1589 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1590 case DeclSpec::SCS_mutable: 1591 // mutable can only appear on non-static class members, so it's always 1592 // an error here 1593 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1594 Invalid = true; 1595 SC = VarDecl::None; 1596 break; 1597 } 1598 1599 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1600 /*IdentifierInfo=*/0, 1601 Context.getTypeDeclType(Record), 1602 DInfo, 1603 SC); 1604 } 1605 Anon->setImplicit(); 1606 1607 // Add the anonymous struct/union object to the current 1608 // context. We'll be referencing this object when we refer to one of 1609 // its members. 1610 Owner->addDecl(Anon); 1611 1612 // Inject the members of the anonymous struct/union into the owning 1613 // context and into the identifier resolver chain for name lookup 1614 // purposes. 1615 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1616 Invalid = true; 1617 1618 // Mark this as an anonymous struct/union type. Note that we do not 1619 // do this until after we have already checked and injected the 1620 // members of this anonymous struct/union type, because otherwise 1621 // the members could be injected twice: once by DeclContext when it 1622 // builds its lookup table, and once by 1623 // InjectAnonymousStructOrUnionMembers. 1624 Record->setAnonymousStructOrUnion(true); 1625 1626 if (Invalid) 1627 Anon->setInvalidDecl(); 1628 1629 return DeclPtrTy::make(Anon); 1630} 1631 1632 1633/// GetNameForDeclarator - Determine the full declaration name for the 1634/// given Declarator. 1635DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1636 return GetNameFromUnqualifiedId(D.getName()); 1637} 1638 1639/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1640DeclarationName Sema::GetNameFromUnqualifiedId(UnqualifiedId &Name) { 1641 switch (Name.getKind()) { 1642 case UnqualifiedId::IK_Identifier: 1643 return DeclarationName(Name.Identifier); 1644 1645 case UnqualifiedId::IK_OperatorFunctionId: 1646 return Context.DeclarationNames.getCXXOperatorName( 1647 Name.OperatorFunctionId.Operator); 1648 1649 case UnqualifiedId::IK_ConversionFunctionId: { 1650 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1651 if (Ty.isNull()) 1652 return DeclarationName(); 1653 1654 return Context.DeclarationNames.getCXXConversionFunctionName( 1655 Context.getCanonicalType(Ty)); 1656 } 1657 1658 case UnqualifiedId::IK_ConstructorName: { 1659 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1660 if (Ty.isNull()) 1661 return DeclarationName(); 1662 1663 return Context.DeclarationNames.getCXXConstructorName( 1664 Context.getCanonicalType(Ty)); 1665 } 1666 1667 case UnqualifiedId::IK_DestructorName: { 1668 QualType Ty = GetTypeFromParser(Name.DestructorName); 1669 if (Ty.isNull()) 1670 return DeclarationName(); 1671 1672 return Context.DeclarationNames.getCXXDestructorName( 1673 Context.getCanonicalType(Ty)); 1674 } 1675 1676 case UnqualifiedId::IK_TemplateId: { 1677 TemplateName TName 1678 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1679 if (TemplateDecl *Template = TName.getAsTemplateDecl()) 1680 return Template->getDeclName(); 1681 if (OverloadedFunctionDecl *Ovl = TName.getAsOverloadedFunctionDecl()) 1682 return Ovl->getDeclName(); 1683 1684 return DeclarationName(); 1685 } 1686 } 1687 1688 assert(false && "Unknown name kind"); 1689 return DeclarationName(); 1690} 1691 1692/// isNearlyMatchingFunction - Determine whether the C++ functions 1693/// Declaration and Definition are "nearly" matching. This heuristic 1694/// is used to improve diagnostics in the case where an out-of-line 1695/// function definition doesn't match any declaration within 1696/// the class or namespace. 1697static bool isNearlyMatchingFunction(ASTContext &Context, 1698 FunctionDecl *Declaration, 1699 FunctionDecl *Definition) { 1700 if (Declaration->param_size() != Definition->param_size()) 1701 return false; 1702 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1703 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1704 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1705 1706 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1707 DefParamTy.getNonReferenceType())) 1708 return false; 1709 } 1710 1711 return true; 1712} 1713 1714Sema::DeclPtrTy 1715Sema::HandleDeclarator(Scope *S, Declarator &D, 1716 MultiTemplateParamsArg TemplateParamLists, 1717 bool IsFunctionDefinition) { 1718 DeclarationName Name = GetNameForDeclarator(D); 1719 1720 // All of these full declarators require an identifier. If it doesn't have 1721 // one, the ParsedFreeStandingDeclSpec action should be used. 1722 if (!Name) { 1723 if (!D.isInvalidType()) // Reject this if we think it is valid. 1724 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1725 diag::err_declarator_need_ident) 1726 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1727 return DeclPtrTy(); 1728 } 1729 1730 // The scope passed in may not be a decl scope. Zip up the scope tree until 1731 // we find one that is. 1732 while ((S->getFlags() & Scope::DeclScope) == 0 || 1733 (S->getFlags() & Scope::TemplateParamScope) != 0) 1734 S = S->getParent(); 1735 1736 // If this is an out-of-line definition of a member of a class template 1737 // or class template partial specialization, we may need to rebuild the 1738 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1739 // for more information. 1740 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1741 // handle expressions properly. 1742 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1743 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1744 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1745 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1746 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1747 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1748 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1749 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1750 // FIXME: Preserve type source info. 1751 QualType T = GetTypeFromParser(DS.getTypeRep()); 1752 EnterDeclaratorContext(S, DC); 1753 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1754 ExitDeclaratorContext(S); 1755 if (T.isNull()) 1756 return DeclPtrTy(); 1757 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1758 } 1759 } 1760 1761 DeclContext *DC; 1762 NamedDecl *PrevDecl; 1763 NamedDecl *New; 1764 1765 DeclaratorInfo *DInfo = 0; 1766 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1767 1768 // See if this is a redefinition of a variable in the same scope. 1769 if (D.getCXXScopeSpec().isInvalid()) { 1770 DC = CurContext; 1771 PrevDecl = 0; 1772 D.setInvalidType(); 1773 } else if (!D.getCXXScopeSpec().isSet()) { 1774 LookupNameKind NameKind = LookupOrdinaryName; 1775 1776 // If the declaration we're planning to build will be a function 1777 // or object with linkage, then look for another declaration with 1778 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1779 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1780 /* Do nothing*/; 1781 else if (R->isFunctionType()) { 1782 if (CurContext->isFunctionOrMethod() || 1783 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1784 NameKind = LookupRedeclarationWithLinkage; 1785 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1786 NameKind = LookupRedeclarationWithLinkage; 1787 else if (CurContext->getLookupContext()->isTranslationUnit() && 1788 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1789 NameKind = LookupRedeclarationWithLinkage; 1790 1791 DC = CurContext; 1792 LookupResult R(*this, Name, D.getIdentifierLoc(), NameKind, 1793 LookupResult::ForRedeclaration); 1794 1795 LookupName(R, S, NameKind == LookupRedeclarationWithLinkage); 1796 PrevDecl = R.getAsSingleDecl(Context); 1797 } else { // Something like "int foo::x;" 1798 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1799 1800 if (!DC) { 1801 // If we could not compute the declaration context, it's because the 1802 // declaration context is dependent but does not refer to a class, 1803 // class template, or class template partial specialization. Complain 1804 // and return early, to avoid the coming semantic disaster. 1805 Diag(D.getIdentifierLoc(), 1806 diag::err_template_qualified_declarator_no_match) 1807 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1808 << D.getCXXScopeSpec().getRange(); 1809 return DeclPtrTy(); 1810 } 1811 1812 if (!DC->isDependentContext() && 1813 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1814 return DeclPtrTy(); 1815 1816 LookupResult Res(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1817 LookupResult::ForRedeclaration); 1818 LookupQualifiedName(Res, DC); 1819 PrevDecl = Res.getAsSingleDecl(Context); 1820 1821 // C++ 7.3.1.2p2: 1822 // Members (including explicit specializations of templates) of a named 1823 // namespace can also be defined outside that namespace by explicit 1824 // qualification of the name being defined, provided that the entity being 1825 // defined was already declared in the namespace and the definition appears 1826 // after the point of declaration in a namespace that encloses the 1827 // declarations namespace. 1828 // 1829 // Note that we only check the context at this point. We don't yet 1830 // have enough information to make sure that PrevDecl is actually 1831 // the declaration we want to match. For example, given: 1832 // 1833 // class X { 1834 // void f(); 1835 // void f(float); 1836 // }; 1837 // 1838 // void X::f(int) { } // ill-formed 1839 // 1840 // In this case, PrevDecl will point to the overload set 1841 // containing the two f's declared in X, but neither of them 1842 // matches. 1843 1844 // First check whether we named the global scope. 1845 if (isa<TranslationUnitDecl>(DC)) { 1846 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1847 << Name << D.getCXXScopeSpec().getRange(); 1848 } else { 1849 DeclContext *Cur = CurContext; 1850 while (isa<LinkageSpecDecl>(Cur)) 1851 Cur = Cur->getParent(); 1852 if (!Cur->Encloses(DC)) { 1853 // The qualifying scope doesn't enclose the original declaration. 1854 // Emit diagnostic based on current scope. 1855 SourceLocation L = D.getIdentifierLoc(); 1856 SourceRange R = D.getCXXScopeSpec().getRange(); 1857 if (isa<FunctionDecl>(Cur)) 1858 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1859 else 1860 Diag(L, diag::err_invalid_declarator_scope) 1861 << Name << cast<NamedDecl>(DC) << R; 1862 D.setInvalidType(); 1863 } 1864 } 1865 } 1866 1867 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1868 // Maybe we will complain about the shadowed template parameter. 1869 if (!D.isInvalidType()) 1870 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1871 D.setInvalidType(); 1872 1873 // Just pretend that we didn't see the previous declaration. 1874 PrevDecl = 0; 1875 } 1876 1877 // In C++, the previous declaration we find might be a tag type 1878 // (class or enum). In this case, the new declaration will hide the 1879 // tag type. Note that this does does not apply if we're declaring a 1880 // typedef (C++ [dcl.typedef]p4). 1881 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1882 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1883 PrevDecl = 0; 1884 1885 bool Redeclaration = false; 1886 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1887 if (TemplateParamLists.size()) { 1888 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1889 return DeclPtrTy(); 1890 } 1891 1892 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1893 } else if (R->isFunctionType()) { 1894 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1895 move(TemplateParamLists), 1896 IsFunctionDefinition, Redeclaration); 1897 } else { 1898 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1899 move(TemplateParamLists), 1900 Redeclaration); 1901 } 1902 1903 if (New == 0) 1904 return DeclPtrTy(); 1905 1906 // If this has an identifier and is not an invalid redeclaration or 1907 // function template specialization, add it to the scope stack. 1908 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1909 !(isa<FunctionDecl>(New) && 1910 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1911 PushOnScopeChains(New, S); 1912 1913 return DeclPtrTy::make(New); 1914} 1915 1916/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1917/// types into constant array types in certain situations which would otherwise 1918/// be errors (for GCC compatibility). 1919static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1920 ASTContext &Context, 1921 bool &SizeIsNegative) { 1922 // This method tries to turn a variable array into a constant 1923 // array even when the size isn't an ICE. This is necessary 1924 // for compatibility with code that depends on gcc's buggy 1925 // constant expression folding, like struct {char x[(int)(char*)2];} 1926 SizeIsNegative = false; 1927 1928 QualifierCollector Qs; 1929 const Type *Ty = Qs.strip(T); 1930 1931 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1932 QualType Pointee = PTy->getPointeeType(); 1933 QualType FixedType = 1934 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1935 if (FixedType.isNull()) return FixedType; 1936 FixedType = Context.getPointerType(FixedType); 1937 return Qs.apply(FixedType); 1938 } 1939 1940 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1941 if (!VLATy) 1942 return QualType(); 1943 // FIXME: We should probably handle this case 1944 if (VLATy->getElementType()->isVariablyModifiedType()) 1945 return QualType(); 1946 1947 Expr::EvalResult EvalResult; 1948 if (!VLATy->getSizeExpr() || 1949 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1950 !EvalResult.Val.isInt()) 1951 return QualType(); 1952 1953 llvm::APSInt &Res = EvalResult.Val.getInt(); 1954 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1955 // TODO: preserve the size expression in declarator info 1956 return Context.getConstantArrayType(VLATy->getElementType(), 1957 Res, ArrayType::Normal, 0); 1958 } 1959 1960 SizeIsNegative = true; 1961 return QualType(); 1962} 1963 1964/// \brief Register the given locally-scoped external C declaration so 1965/// that it can be found later for redeclarations 1966void 1967Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1968 Scope *S) { 1969 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1970 "Decl is not a locally-scoped decl!"); 1971 // Note that we have a locally-scoped external with this name. 1972 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1973 1974 if (!PrevDecl) 1975 return; 1976 1977 // If there was a previous declaration of this variable, it may be 1978 // in our identifier chain. Update the identifier chain with the new 1979 // declaration. 1980 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1981 // The previous declaration was found on the identifer resolver 1982 // chain, so remove it from its scope. 1983 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1984 S = S->getParent(); 1985 1986 if (S) 1987 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1988 } 1989} 1990 1991/// \brief Diagnose function specifiers on a declaration of an identifier that 1992/// does not identify a function. 1993void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1994 // FIXME: We should probably indicate the identifier in question to avoid 1995 // confusion for constructs like "inline int a(), b;" 1996 if (D.getDeclSpec().isInlineSpecified()) 1997 Diag(D.getDeclSpec().getInlineSpecLoc(), 1998 diag::err_inline_non_function); 1999 2000 if (D.getDeclSpec().isVirtualSpecified()) 2001 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2002 diag::err_virtual_non_function); 2003 2004 if (D.getDeclSpec().isExplicitSpecified()) 2005 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2006 diag::err_explicit_non_function); 2007} 2008 2009NamedDecl* 2010Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2011 QualType R, DeclaratorInfo *DInfo, 2012 NamedDecl* PrevDecl, bool &Redeclaration) { 2013 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2014 if (D.getCXXScopeSpec().isSet()) { 2015 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2016 << D.getCXXScopeSpec().getRange(); 2017 D.setInvalidType(); 2018 // Pretend we didn't see the scope specifier. 2019 DC = 0; 2020 } 2021 2022 if (getLangOptions().CPlusPlus) { 2023 // Check that there are no default arguments (C++ only). 2024 CheckExtraCXXDefaultArguments(D); 2025 } 2026 2027 DiagnoseFunctionSpecifiers(D); 2028 2029 if (D.getDeclSpec().isThreadSpecified()) 2030 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2031 2032 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 2033 if (!NewTD) return 0; 2034 2035 // Handle attributes prior to checking for duplicates in MergeVarDecl 2036 ProcessDeclAttributes(S, NewTD, D); 2037 // Merge the decl with the existing one if appropriate. If the decl is 2038 // in an outer scope, it isn't the same thing. 2039 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2040 Redeclaration = true; 2041 MergeTypeDefDecl(NewTD, PrevDecl); 2042 } 2043 2044 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2045 // then it shall have block scope. 2046 QualType T = NewTD->getUnderlyingType(); 2047 if (T->isVariablyModifiedType()) { 2048 CurFunctionNeedsScopeChecking = true; 2049 2050 if (S->getFnParent() == 0) { 2051 bool SizeIsNegative; 2052 QualType FixedTy = 2053 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2054 if (!FixedTy.isNull()) { 2055 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2056 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2057 } else { 2058 if (SizeIsNegative) 2059 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2060 else if (T->isVariableArrayType()) 2061 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2062 else 2063 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2064 NewTD->setInvalidDecl(); 2065 } 2066 } 2067 } 2068 2069 // If this is the C FILE type, notify the AST context. 2070 if (IdentifierInfo *II = NewTD->getIdentifier()) 2071 if (!NewTD->isInvalidDecl() && 2072 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2073 if (II->isStr("FILE")) 2074 Context.setFILEDecl(NewTD); 2075 else if (II->isStr("jmp_buf")) 2076 Context.setjmp_bufDecl(NewTD); 2077 else if (II->isStr("sigjmp_buf")) 2078 Context.setsigjmp_bufDecl(NewTD); 2079 } 2080 2081 return NewTD; 2082} 2083 2084/// \brief Determines whether the given declaration is an out-of-scope 2085/// previous declaration. 2086/// 2087/// This routine should be invoked when name lookup has found a 2088/// previous declaration (PrevDecl) that is not in the scope where a 2089/// new declaration by the same name is being introduced. If the new 2090/// declaration occurs in a local scope, previous declarations with 2091/// linkage may still be considered previous declarations (C99 2092/// 6.2.2p4-5, C++ [basic.link]p6). 2093/// 2094/// \param PrevDecl the previous declaration found by name 2095/// lookup 2096/// 2097/// \param DC the context in which the new declaration is being 2098/// declared. 2099/// 2100/// \returns true if PrevDecl is an out-of-scope previous declaration 2101/// for a new delcaration with the same name. 2102static bool 2103isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2104 ASTContext &Context) { 2105 if (!PrevDecl) 2106 return 0; 2107 2108 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2109 // case we need to check each of the overloaded functions. 2110 if (!PrevDecl->hasLinkage()) 2111 return false; 2112 2113 if (Context.getLangOptions().CPlusPlus) { 2114 // C++ [basic.link]p6: 2115 // If there is a visible declaration of an entity with linkage 2116 // having the same name and type, ignoring entities declared 2117 // outside the innermost enclosing namespace scope, the block 2118 // scope declaration declares that same entity and receives the 2119 // linkage of the previous declaration. 2120 DeclContext *OuterContext = DC->getLookupContext(); 2121 if (!OuterContext->isFunctionOrMethod()) 2122 // This rule only applies to block-scope declarations. 2123 return false; 2124 else { 2125 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2126 if (PrevOuterContext->isRecord()) 2127 // We found a member function: ignore it. 2128 return false; 2129 else { 2130 // Find the innermost enclosing namespace for the new and 2131 // previous declarations. 2132 while (!OuterContext->isFileContext()) 2133 OuterContext = OuterContext->getParent(); 2134 while (!PrevOuterContext->isFileContext()) 2135 PrevOuterContext = PrevOuterContext->getParent(); 2136 2137 // The previous declaration is in a different namespace, so it 2138 // isn't the same function. 2139 if (OuterContext->getPrimaryContext() != 2140 PrevOuterContext->getPrimaryContext()) 2141 return false; 2142 } 2143 } 2144 } 2145 2146 return true; 2147} 2148 2149NamedDecl* 2150Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2151 QualType R, DeclaratorInfo *DInfo, 2152 NamedDecl* PrevDecl, 2153 MultiTemplateParamsArg TemplateParamLists, 2154 bool &Redeclaration) { 2155 DeclarationName Name = GetNameForDeclarator(D); 2156 2157 // Check that there are no default arguments (C++ only). 2158 if (getLangOptions().CPlusPlus) 2159 CheckExtraCXXDefaultArguments(D); 2160 2161 VarDecl *NewVD; 2162 VarDecl::StorageClass SC; 2163 switch (D.getDeclSpec().getStorageClassSpec()) { 2164 default: assert(0 && "Unknown storage class!"); 2165 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2166 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2167 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2168 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2169 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2170 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2171 case DeclSpec::SCS_mutable: 2172 // mutable can only appear on non-static class members, so it's always 2173 // an error here 2174 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2175 D.setInvalidType(); 2176 SC = VarDecl::None; 2177 break; 2178 } 2179 2180 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2181 if (!II) { 2182 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2183 << Name.getAsString(); 2184 return 0; 2185 } 2186 2187 DiagnoseFunctionSpecifiers(D); 2188 2189 if (!DC->isRecord() && S->getFnParent() == 0) { 2190 // C99 6.9p2: The storage-class specifiers auto and register shall not 2191 // appear in the declaration specifiers in an external declaration. 2192 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2193 2194 // If this is a register variable with an asm label specified, then this 2195 // is a GNU extension. 2196 if (SC == VarDecl::Register && D.getAsmLabel()) 2197 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2198 else 2199 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2200 D.setInvalidType(); 2201 } 2202 } 2203 if (DC->isRecord() && !CurContext->isRecord()) { 2204 // This is an out-of-line definition of a static data member. 2205 if (SC == VarDecl::Static) { 2206 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2207 diag::err_static_out_of_line) 2208 << CodeModificationHint::CreateRemoval( 2209 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2210 } else if (SC == VarDecl::None) 2211 SC = VarDecl::Static; 2212 } 2213 if (SC == VarDecl::Static) { 2214 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2215 if (RD->isLocalClass()) 2216 Diag(D.getIdentifierLoc(), 2217 diag::err_static_data_member_not_allowed_in_local_class) 2218 << Name << RD->getDeclName(); 2219 } 2220 } 2221 2222 // Match up the template parameter lists with the scope specifier, then 2223 // determine whether we have a template or a template specialization. 2224 bool isExplicitSpecialization = false; 2225 if (TemplateParameterList *TemplateParams 2226 = MatchTemplateParametersToScopeSpecifier( 2227 D.getDeclSpec().getSourceRange().getBegin(), 2228 D.getCXXScopeSpec(), 2229 (TemplateParameterList**)TemplateParamLists.get(), 2230 TemplateParamLists.size(), 2231 isExplicitSpecialization)) { 2232 if (TemplateParams->size() > 0) { 2233 // There is no such thing as a variable template. 2234 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2235 << II 2236 << SourceRange(TemplateParams->getTemplateLoc(), 2237 TemplateParams->getRAngleLoc()); 2238 return 0; 2239 } else { 2240 // There is an extraneous 'template<>' for this variable. Complain 2241 // about it, but allow the declaration of the variable. 2242 Diag(TemplateParams->getTemplateLoc(), 2243 diag::err_template_variable_noparams) 2244 << II 2245 << SourceRange(TemplateParams->getTemplateLoc(), 2246 TemplateParams->getRAngleLoc()); 2247 2248 isExplicitSpecialization = true; 2249 } 2250 } 2251 2252 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2253 II, R, DInfo, SC); 2254 2255 if (D.isInvalidType()) 2256 NewVD->setInvalidDecl(); 2257 2258 if (D.getDeclSpec().isThreadSpecified()) { 2259 if (NewVD->hasLocalStorage()) 2260 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2261 else if (!Context.Target.isTLSSupported()) 2262 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2263 else 2264 NewVD->setThreadSpecified(true); 2265 } 2266 2267 // Set the lexical context. If the declarator has a C++ scope specifier, the 2268 // lexical context will be different from the semantic context. 2269 NewVD->setLexicalDeclContext(CurContext); 2270 2271 // Handle attributes prior to checking for duplicates in MergeVarDecl 2272 ProcessDeclAttributes(S, NewVD, D); 2273 2274 // Handle GNU asm-label extension (encoded as an attribute). 2275 if (Expr *E = (Expr*) D.getAsmLabel()) { 2276 // The parser guarantees this is a string. 2277 StringLiteral *SE = cast<StringLiteral>(E); 2278 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2279 SE->getByteLength()))); 2280 } 2281 2282 // If name lookup finds a previous declaration that is not in the 2283 // same scope as the new declaration, this may still be an 2284 // acceptable redeclaration. 2285 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2286 !(NewVD->hasLinkage() && 2287 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2288 PrevDecl = 0; 2289 2290 // Merge the decl with the existing one if appropriate. 2291 if (PrevDecl) { 2292 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2293 // The user tried to define a non-static data member 2294 // out-of-line (C++ [dcl.meaning]p1). 2295 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2296 << D.getCXXScopeSpec().getRange(); 2297 PrevDecl = 0; 2298 NewVD->setInvalidDecl(); 2299 } 2300 } else if (D.getCXXScopeSpec().isSet()) { 2301 // No previous declaration in the qualifying scope. 2302 Diag(D.getIdentifierLoc(), diag::err_no_member) 2303 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2304 << D.getCXXScopeSpec().getRange(); 2305 NewVD->setInvalidDecl(); 2306 } 2307 2308 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2309 2310 // This is an explicit specialization of a static data member. Check it. 2311 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2312 CheckMemberSpecialization(NewVD, PrevDecl)) 2313 NewVD->setInvalidDecl(); 2314 2315 // attributes declared post-definition are currently ignored 2316 if (PrevDecl) { 2317 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2318 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2319 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2320 Diag(Def->getLocation(), diag::note_previous_definition); 2321 } 2322 } 2323 2324 // If this is a locally-scoped extern C variable, update the map of 2325 // such variables. 2326 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2327 !NewVD->isInvalidDecl()) 2328 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2329 2330 return NewVD; 2331} 2332 2333/// \brief Perform semantic checking on a newly-created variable 2334/// declaration. 2335/// 2336/// This routine performs all of the type-checking required for a 2337/// variable declaration once it has been built. It is used both to 2338/// check variables after they have been parsed and their declarators 2339/// have been translated into a declaration, and to check variables 2340/// that have been instantiated from a template. 2341/// 2342/// Sets NewVD->isInvalidDecl() if an error was encountered. 2343void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2344 bool &Redeclaration) { 2345 // If the decl is already known invalid, don't check it. 2346 if (NewVD->isInvalidDecl()) 2347 return; 2348 2349 QualType T = NewVD->getType(); 2350 2351 if (T->isObjCInterfaceType()) { 2352 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2353 return NewVD->setInvalidDecl(); 2354 } 2355 2356 // The variable can not have an abstract class type. 2357 if (RequireNonAbstractType(NewVD->getLocation(), T, 2358 diag::err_abstract_type_in_decl, 2359 AbstractVariableType)) 2360 return NewVD->setInvalidDecl(); 2361 2362 // Emit an error if an address space was applied to decl with local storage. 2363 // This includes arrays of objects with address space qualifiers, but not 2364 // automatic variables that point to other address spaces. 2365 // ISO/IEC TR 18037 S5.1.2 2366 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2367 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2368 return NewVD->setInvalidDecl(); 2369 } 2370 2371 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2372 && !NewVD->hasAttr<BlocksAttr>()) 2373 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2374 2375 bool isVM = T->isVariablyModifiedType(); 2376 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2377 NewVD->hasAttr<BlocksAttr>()) 2378 CurFunctionNeedsScopeChecking = true; 2379 2380 if ((isVM && NewVD->hasLinkage()) || 2381 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2382 bool SizeIsNegative; 2383 QualType FixedTy = 2384 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2385 2386 if (FixedTy.isNull() && T->isVariableArrayType()) { 2387 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2388 // FIXME: This won't give the correct result for 2389 // int a[10][n]; 2390 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2391 2392 if (NewVD->isFileVarDecl()) 2393 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2394 << SizeRange; 2395 else if (NewVD->getStorageClass() == VarDecl::Static) 2396 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2397 << SizeRange; 2398 else 2399 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2400 << SizeRange; 2401 return NewVD->setInvalidDecl(); 2402 } 2403 2404 if (FixedTy.isNull()) { 2405 if (NewVD->isFileVarDecl()) 2406 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2407 else 2408 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2409 return NewVD->setInvalidDecl(); 2410 } 2411 2412 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2413 NewVD->setType(FixedTy); 2414 } 2415 2416 if (!PrevDecl && NewVD->isExternC()) { 2417 // Since we did not find anything by this name and we're declaring 2418 // an extern "C" variable, look for a non-visible extern "C" 2419 // declaration with the same name. 2420 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2421 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2422 if (Pos != LocallyScopedExternalDecls.end()) 2423 PrevDecl = Pos->second; 2424 } 2425 2426 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2427 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2428 << T; 2429 return NewVD->setInvalidDecl(); 2430 } 2431 2432 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2433 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2434 return NewVD->setInvalidDecl(); 2435 } 2436 2437 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2438 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2439 return NewVD->setInvalidDecl(); 2440 } 2441 2442 if (PrevDecl) { 2443 Redeclaration = true; 2444 MergeVarDecl(NewVD, PrevDecl); 2445 } 2446} 2447 2448static bool isUsingDecl(Decl *D) { 2449 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2450} 2451 2452/// \brief Data used with FindOverriddenMethod 2453struct FindOverriddenMethodData { 2454 Sema *S; 2455 CXXMethodDecl *Method; 2456}; 2457 2458/// \brief Member lookup function that determines whether a given C++ 2459/// method overrides a method in a base class, to be used with 2460/// CXXRecordDecl::lookupInBases(). 2461static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2462 CXXBasePath &Path, 2463 void *UserData) { 2464 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2465 2466 FindOverriddenMethodData *Data 2467 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2468 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2469 Path.Decls.first != Path.Decls.second; 2470 ++Path.Decls.first) { 2471 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2472 OverloadedFunctionDecl::function_iterator MatchedDecl; 2473 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2474 return true; 2475 } 2476 } 2477 2478 return false; 2479} 2480 2481NamedDecl* 2482Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2483 QualType R, DeclaratorInfo *DInfo, 2484 NamedDecl* PrevDecl, 2485 MultiTemplateParamsArg TemplateParamLists, 2486 bool IsFunctionDefinition, bool &Redeclaration) { 2487 assert(R.getTypePtr()->isFunctionType()); 2488 2489 DeclarationName Name = GetNameForDeclarator(D); 2490 FunctionDecl::StorageClass SC = FunctionDecl::None; 2491 switch (D.getDeclSpec().getStorageClassSpec()) { 2492 default: assert(0 && "Unknown storage class!"); 2493 case DeclSpec::SCS_auto: 2494 case DeclSpec::SCS_register: 2495 case DeclSpec::SCS_mutable: 2496 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2497 diag::err_typecheck_sclass_func); 2498 D.setInvalidType(); 2499 break; 2500 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2501 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2502 case DeclSpec::SCS_static: { 2503 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2504 // C99 6.7.1p5: 2505 // The declaration of an identifier for a function that has 2506 // block scope shall have no explicit storage-class specifier 2507 // other than extern 2508 // See also (C++ [dcl.stc]p4). 2509 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2510 diag::err_static_block_func); 2511 SC = FunctionDecl::None; 2512 } else 2513 SC = FunctionDecl::Static; 2514 break; 2515 } 2516 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2517 } 2518 2519 if (D.getDeclSpec().isThreadSpecified()) 2520 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2521 2522 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2523 bool isInline = D.getDeclSpec().isInlineSpecified(); 2524 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2525 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2526 2527 // Check that the return type is not an abstract class type. 2528 // For record types, this is done by the AbstractClassUsageDiagnoser once 2529 // the class has been completely parsed. 2530 if (!DC->isRecord() && 2531 RequireNonAbstractType(D.getIdentifierLoc(), 2532 R->getAs<FunctionType>()->getResultType(), 2533 diag::err_abstract_type_in_decl, 2534 AbstractReturnType)) 2535 D.setInvalidType(); 2536 2537 // Do not allow returning a objc interface by-value. 2538 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2539 Diag(D.getIdentifierLoc(), 2540 diag::err_object_cannot_be_passed_returned_by_value) << 0 2541 << R->getAs<FunctionType>()->getResultType(); 2542 D.setInvalidType(); 2543 } 2544 2545 bool isVirtualOkay = false; 2546 FunctionDecl *NewFD; 2547 2548 if (isFriend) { 2549 // DC is the namespace in which the function is being declared. 2550 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2551 "friend function being created in a non-namespace context"); 2552 2553 // C++ [class.friend]p5 2554 // A function can be defined in a friend declaration of a 2555 // class . . . . Such a function is implicitly inline. 2556 isInline |= IsFunctionDefinition; 2557 } 2558 2559 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2560 // This is a C++ constructor declaration. 2561 assert(DC->isRecord() && 2562 "Constructors can only be declared in a member context"); 2563 2564 R = CheckConstructorDeclarator(D, R, SC); 2565 2566 // Create the new declaration 2567 NewFD = CXXConstructorDecl::Create(Context, 2568 cast<CXXRecordDecl>(DC), 2569 D.getIdentifierLoc(), Name, R, DInfo, 2570 isExplicit, isInline, 2571 /*isImplicitlyDeclared=*/false); 2572 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2573 // This is a C++ destructor declaration. 2574 if (DC->isRecord()) { 2575 R = CheckDestructorDeclarator(D, SC); 2576 2577 NewFD = CXXDestructorDecl::Create(Context, 2578 cast<CXXRecordDecl>(DC), 2579 D.getIdentifierLoc(), Name, R, 2580 isInline, 2581 /*isImplicitlyDeclared=*/false); 2582 2583 isVirtualOkay = true; 2584 } else { 2585 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2586 2587 // Create a FunctionDecl to satisfy the function definition parsing 2588 // code path. 2589 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2590 Name, R, DInfo, SC, isInline, 2591 /*hasPrototype=*/true); 2592 D.setInvalidType(); 2593 } 2594 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2595 if (!DC->isRecord()) { 2596 Diag(D.getIdentifierLoc(), 2597 diag::err_conv_function_not_member); 2598 return 0; 2599 } 2600 2601 CheckConversionDeclarator(D, R, SC); 2602 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2603 D.getIdentifierLoc(), Name, R, DInfo, 2604 isInline, isExplicit); 2605 2606 isVirtualOkay = true; 2607 } else if (DC->isRecord()) { 2608 // If the of the function is the same as the name of the record, then this 2609 // must be an invalid constructor that has a return type. 2610 // (The parser checks for a return type and makes the declarator a 2611 // constructor if it has no return type). 2612 // must have an invalid constructor that has a return type 2613 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2614 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2615 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2616 << SourceRange(D.getIdentifierLoc()); 2617 return 0; 2618 } 2619 2620 bool isStatic = SC == FunctionDecl::Static; 2621 2622 // [class.free]p1: 2623 // Any allocation function for a class T is a static member 2624 // (even if not explicitly declared static). 2625 if (Name.getCXXOverloadedOperator() == OO_New || 2626 Name.getCXXOverloadedOperator() == OO_Array_New) 2627 isStatic = true; 2628 2629 // [class.free]p6 Any deallocation function for a class X is a static member 2630 // (even if not explicitly declared static). 2631 if (Name.getCXXOverloadedOperator() == OO_Delete || 2632 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2633 isStatic = true; 2634 2635 // This is a C++ method declaration. 2636 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2637 D.getIdentifierLoc(), Name, R, DInfo, 2638 isStatic, isInline); 2639 2640 isVirtualOkay = !isStatic; 2641 } else { 2642 // Determine whether the function was written with a 2643 // prototype. This true when: 2644 // - we're in C++ (where every function has a prototype), 2645 // - there is a prototype in the declarator, or 2646 // - the type R of the function is some kind of typedef or other reference 2647 // to a type name (which eventually refers to a function type). 2648 bool HasPrototype = 2649 getLangOptions().CPlusPlus || 2650 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2651 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2652 2653 NewFD = FunctionDecl::Create(Context, DC, 2654 D.getIdentifierLoc(), 2655 Name, R, DInfo, SC, isInline, HasPrototype); 2656 } 2657 2658 if (D.isInvalidType()) 2659 NewFD->setInvalidDecl(); 2660 2661 // Set the lexical context. If the declarator has a C++ 2662 // scope specifier, or is the object of a friend declaration, the 2663 // lexical context will be different from the semantic context. 2664 NewFD->setLexicalDeclContext(CurContext); 2665 2666 // Match up the template parameter lists with the scope specifier, then 2667 // determine whether we have a template or a template specialization. 2668 FunctionTemplateDecl *FunctionTemplate = 0; 2669 bool isExplicitSpecialization = false; 2670 bool isFunctionTemplateSpecialization = false; 2671 if (TemplateParameterList *TemplateParams 2672 = MatchTemplateParametersToScopeSpecifier( 2673 D.getDeclSpec().getSourceRange().getBegin(), 2674 D.getCXXScopeSpec(), 2675 (TemplateParameterList**)TemplateParamLists.get(), 2676 TemplateParamLists.size(), 2677 isExplicitSpecialization)) { 2678 if (TemplateParams->size() > 0) { 2679 // This is a function template 2680 2681 // Check that we can declare a template here. 2682 if (CheckTemplateDeclScope(S, TemplateParams)) 2683 return 0; 2684 2685 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2686 NewFD->getLocation(), 2687 Name, TemplateParams, 2688 NewFD); 2689 FunctionTemplate->setLexicalDeclContext(CurContext); 2690 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2691 } else { 2692 // This is a function template specialization. 2693 isFunctionTemplateSpecialization = true; 2694 } 2695 2696 // FIXME: Free this memory properly. 2697 TemplateParamLists.release(); 2698 } 2699 2700 // C++ [dcl.fct.spec]p5: 2701 // The virtual specifier shall only be used in declarations of 2702 // nonstatic class member functions that appear within a 2703 // member-specification of a class declaration; see 10.3. 2704 // 2705 if (isVirtual && !NewFD->isInvalidDecl()) { 2706 if (!isVirtualOkay) { 2707 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2708 diag::err_virtual_non_function); 2709 } else if (!CurContext->isRecord()) { 2710 // 'virtual' was specified outside of the class. 2711 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2712 << CodeModificationHint::CreateRemoval( 2713 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2714 } else { 2715 // Okay: Add virtual to the method. 2716 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2717 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2718 CurClass->setAggregate(false); 2719 CurClass->setPOD(false); 2720 CurClass->setEmpty(false); 2721 CurClass->setPolymorphic(true); 2722 CurClass->setHasTrivialConstructor(false); 2723 CurClass->setHasTrivialCopyConstructor(false); 2724 CurClass->setHasTrivialCopyAssignment(false); 2725 } 2726 } 2727 2728 if (isFriend) { 2729 if (FunctionTemplate) { 2730 FunctionTemplate->setObjectOfFriendDecl( 2731 /* PreviouslyDeclared= */ PrevDecl != NULL); 2732 FunctionTemplate->setAccess(AS_public); 2733 } 2734 else 2735 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2736 2737 NewFD->setAccess(AS_public); 2738 } 2739 2740 2741 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2742 // Look for virtual methods in base classes that this method might override. 2743 CXXBasePaths Paths; 2744 FindOverriddenMethodData Data; 2745 Data.Method = NewMD; 2746 Data.S = this; 2747 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2748 Paths)) { 2749 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2750 E = Paths.found_decls_end(); I != E; ++I) { 2751 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2752 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2753 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2754 NewMD->addOverriddenMethod(OldMD); 2755 } 2756 } 2757 } 2758 } 2759 2760 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2761 !CurContext->isRecord()) { 2762 // C++ [class.static]p1: 2763 // A data or function member of a class may be declared static 2764 // in a class definition, in which case it is a static member of 2765 // the class. 2766 2767 // Complain about the 'static' specifier if it's on an out-of-line 2768 // member function definition. 2769 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2770 diag::err_static_out_of_line) 2771 << CodeModificationHint::CreateRemoval( 2772 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2773 } 2774 2775 // Handle GNU asm-label extension (encoded as an attribute). 2776 if (Expr *E = (Expr*) D.getAsmLabel()) { 2777 // The parser guarantees this is a string. 2778 StringLiteral *SE = cast<StringLiteral>(E); 2779 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2780 SE->getByteLength()))); 2781 } 2782 2783 // Copy the parameter declarations from the declarator D to the function 2784 // declaration NewFD, if they are available. First scavenge them into Params. 2785 llvm::SmallVector<ParmVarDecl*, 16> Params; 2786 if (D.getNumTypeObjects() > 0) { 2787 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2788 2789 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2790 // function that takes no arguments, not a function that takes a 2791 // single void argument. 2792 // We let through "const void" here because Sema::GetTypeForDeclarator 2793 // already checks for that case. 2794 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2795 FTI.ArgInfo[0].Param && 2796 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2797 // Empty arg list, don't push any params. 2798 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2799 2800 // In C++, the empty parameter-type-list must be spelled "void"; a 2801 // typedef of void is not permitted. 2802 if (getLangOptions().CPlusPlus && 2803 Param->getType().getUnqualifiedType() != Context.VoidTy) 2804 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2805 // FIXME: Leaks decl? 2806 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2807 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2808 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2809 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2810 Param->setDeclContext(NewFD); 2811 Params.push_back(Param); 2812 } 2813 } 2814 2815 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2816 // When we're declaring a function with a typedef, typeof, etc as in the 2817 // following example, we'll need to synthesize (unnamed) 2818 // parameters for use in the declaration. 2819 // 2820 // @code 2821 // typedef void fn(int); 2822 // fn f; 2823 // @endcode 2824 2825 // Synthesize a parameter for each argument type. 2826 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2827 AE = FT->arg_type_end(); AI != AE; ++AI) { 2828 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2829 SourceLocation(), 0, 2830 *AI, /*DInfo=*/0, 2831 VarDecl::None, 0); 2832 Param->setImplicit(); 2833 Params.push_back(Param); 2834 } 2835 } else { 2836 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2837 "Should not need args for typedef of non-prototype fn"); 2838 } 2839 // Finally, we know we have the right number of parameters, install them. 2840 NewFD->setParams(Context, Params.data(), Params.size()); 2841 2842 // If name lookup finds a previous declaration that is not in the 2843 // same scope as the new declaration, this may still be an 2844 // acceptable redeclaration. 2845 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2846 !(NewFD->hasLinkage() && 2847 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2848 PrevDecl = 0; 2849 2850 // If the declarator is a template-id, translate the parser's template 2851 // argument list into our AST format. 2852 bool HasExplicitTemplateArgs = false; 2853 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 2854 SourceLocation LAngleLoc, RAngleLoc; 2855 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2856 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2857 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2858 TemplateId->getTemplateArgs(), 2859 TemplateId->NumArgs); 2860 translateTemplateArguments(TemplateArgsPtr, 2861 TemplateArgs); 2862 TemplateArgsPtr.release(); 2863 2864 HasExplicitTemplateArgs = true; 2865 LAngleLoc = TemplateId->LAngleLoc; 2866 RAngleLoc = TemplateId->RAngleLoc; 2867 2868 if (FunctionTemplate) { 2869 // FIXME: Diagnose function template with explicit template 2870 // arguments. 2871 HasExplicitTemplateArgs = false; 2872 } else if (!isFunctionTemplateSpecialization && 2873 !D.getDeclSpec().isFriendSpecified()) { 2874 // We have encountered something that the user meant to be a 2875 // specialization (because it has explicitly-specified template 2876 // arguments) but that was not introduced with a "template<>" (or had 2877 // too few of them). 2878 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2879 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2880 << CodeModificationHint::CreateInsertion( 2881 D.getDeclSpec().getSourceRange().getBegin(), 2882 "template<> "); 2883 isFunctionTemplateSpecialization = true; 2884 } 2885 } 2886 2887 if (isFunctionTemplateSpecialization) { 2888 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2889 LAngleLoc, TemplateArgs.data(), 2890 TemplateArgs.size(), RAngleLoc, 2891 PrevDecl)) 2892 NewFD->setInvalidDecl(); 2893 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2894 CheckMemberSpecialization(NewFD, PrevDecl)) 2895 NewFD->setInvalidDecl(); 2896 2897 // Perform semantic checking on the function declaration. 2898 bool OverloadableAttrRequired = false; // FIXME: HACK! 2899 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2900 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2901 2902 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2903 // An out-of-line member function declaration must also be a 2904 // definition (C++ [dcl.meaning]p1). 2905 // Note that this is not the case for explicit specializations of 2906 // function templates or member functions of class templates, per 2907 // C++ [temp.expl.spec]p2. 2908 if (!IsFunctionDefinition && !isFriend && 2909 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2910 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2911 << D.getCXXScopeSpec().getRange(); 2912 NewFD->setInvalidDecl(); 2913 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2914 // The user tried to provide an out-of-line definition for a 2915 // function that is a member of a class or namespace, but there 2916 // was no such member function declared (C++ [class.mfct]p2, 2917 // C++ [namespace.memdef]p2). For example: 2918 // 2919 // class X { 2920 // void f() const; 2921 // }; 2922 // 2923 // void X::f() { } // ill-formed 2924 // 2925 // Complain about this problem, and attempt to suggest close 2926 // matches (e.g., those that differ only in cv-qualifiers and 2927 // whether the parameter types are references). 2928 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2929 << Name << DC << D.getCXXScopeSpec().getRange(); 2930 NewFD->setInvalidDecl(); 2931 2932 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2933 LookupResult::ForRedeclaration); 2934 LookupQualifiedName(Prev, DC); 2935 assert(!Prev.isAmbiguous() && 2936 "Cannot have an ambiguity in previous-declaration lookup"); 2937 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2938 Func != FuncEnd; ++Func) { 2939 if (isa<FunctionDecl>(*Func) && 2940 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2941 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2942 } 2943 2944 PrevDecl = 0; 2945 } 2946 } 2947 2948 // Handle attributes. We need to have merged decls when handling attributes 2949 // (for example to check for conflicts, etc). 2950 // FIXME: This needs to happen before we merge declarations. Then, 2951 // let attribute merging cope with attribute conflicts. 2952 ProcessDeclAttributes(S, NewFD, D); 2953 2954 // attributes declared post-definition are currently ignored 2955 if (Redeclaration && PrevDecl) { 2956 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2957 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2958 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2959 Diag(Def->getLocation(), diag::note_previous_definition); 2960 } 2961 } 2962 2963 AddKnownFunctionAttributes(NewFD); 2964 2965 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2966 // If a function name is overloadable in C, then every function 2967 // with that name must be marked "overloadable". 2968 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2969 << Redeclaration << NewFD; 2970 if (PrevDecl) 2971 Diag(PrevDecl->getLocation(), 2972 diag::note_attribute_overloadable_prev_overload); 2973 NewFD->addAttr(::new (Context) OverloadableAttr()); 2974 } 2975 2976 // If this is a locally-scoped extern C function, update the 2977 // map of such names. 2978 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2979 && !NewFD->isInvalidDecl()) 2980 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2981 2982 // Set this FunctionDecl's range up to the right paren. 2983 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2984 2985 if (FunctionTemplate && NewFD->isInvalidDecl()) 2986 FunctionTemplate->setInvalidDecl(); 2987 2988 if (FunctionTemplate) 2989 return FunctionTemplate; 2990 2991 return NewFD; 2992} 2993 2994/// \brief Perform semantic checking of a new function declaration. 2995/// 2996/// Performs semantic analysis of the new function declaration 2997/// NewFD. This routine performs all semantic checking that does not 2998/// require the actual declarator involved in the declaration, and is 2999/// used both for the declaration of functions as they are parsed 3000/// (called via ActOnDeclarator) and for the declaration of functions 3001/// that have been instantiated via C++ template instantiation (called 3002/// via InstantiateDecl). 3003/// 3004/// \param IsExplicitSpecialiation whether this new function declaration is 3005/// an explicit specialization of the previous declaration. 3006/// 3007/// This sets NewFD->isInvalidDecl() to true if there was an error. 3008void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 3009 bool IsExplicitSpecialization, 3010 bool &Redeclaration, 3011 bool &OverloadableAttrRequired) { 3012 // If NewFD is already known erroneous, don't do any of this checking. 3013 if (NewFD->isInvalidDecl()) 3014 return; 3015 3016 if (NewFD->getResultType()->isVariablyModifiedType()) { 3017 // Functions returning a variably modified type violate C99 6.7.5.2p2 3018 // because all functions have linkage. 3019 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3020 return NewFD->setInvalidDecl(); 3021 } 3022 3023 if (NewFD->isMain()) 3024 CheckMain(NewFD); 3025 3026 // Check for a previous declaration of this name. 3027 if (!PrevDecl && NewFD->isExternC()) { 3028 // Since we did not find anything by this name and we're declaring 3029 // an extern "C" function, look for a non-visible extern "C" 3030 // declaration with the same name. 3031 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3032 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3033 if (Pos != LocallyScopedExternalDecls.end()) 3034 PrevDecl = Pos->second; 3035 } 3036 3037 // Merge or overload the declaration with an existing declaration of 3038 // the same name, if appropriate. 3039 if (PrevDecl) { 3040 // Determine whether NewFD is an overload of PrevDecl or 3041 // a declaration that requires merging. If it's an overload, 3042 // there's no more work to do here; we'll just add the new 3043 // function to the scope. 3044 OverloadedFunctionDecl::function_iterator MatchedDecl; 3045 3046 if (!getLangOptions().CPlusPlus && 3047 AllowOverloadingOfFunction(PrevDecl, Context)) { 3048 OverloadableAttrRequired = true; 3049 3050 // Functions marked "overloadable" must have a prototype (that 3051 // we can't get through declaration merging). 3052 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3053 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3054 << NewFD; 3055 Redeclaration = true; 3056 3057 // Turn this into a variadic function with no parameters. 3058 QualType R = Context.getFunctionType( 3059 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3060 0, 0, true, 0); 3061 NewFD->setType(R); 3062 return NewFD->setInvalidDecl(); 3063 } 3064 } 3065 3066 if (PrevDecl && 3067 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3068 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3069 Redeclaration = true; 3070 Decl *OldDecl = PrevDecl; 3071 3072 // If PrevDecl was an overloaded function, extract the 3073 // FunctionDecl that matched. 3074 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3075 OldDecl = *MatchedDecl; 3076 3077 // NewFD and OldDecl represent declarations that need to be 3078 // merged. 3079 if (MergeFunctionDecl(NewFD, OldDecl)) 3080 return NewFD->setInvalidDecl(); 3081 3082 if (FunctionTemplateDecl *OldTemplateDecl 3083 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3084 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3085 FunctionTemplateDecl *NewTemplateDecl 3086 = NewFD->getDescribedFunctionTemplate(); 3087 assert(NewTemplateDecl && "Template/non-template mismatch"); 3088 if (CXXMethodDecl *Method 3089 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3090 Method->setAccess(OldTemplateDecl->getAccess()); 3091 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3092 } 3093 3094 // If this is an explicit specialization of a member that is a function 3095 // template, mark it as a member specialization. 3096 if (IsExplicitSpecialization && 3097 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3098 NewTemplateDecl->setMemberSpecialization(); 3099 assert(OldTemplateDecl->isMemberSpecialization()); 3100 } 3101 } else { 3102 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3103 NewFD->setAccess(OldDecl->getAccess()); 3104 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3105 } 3106 } 3107 } 3108 3109 // Semantic checking for this function declaration (in isolation). 3110 if (getLangOptions().CPlusPlus) { 3111 // C++-specific checks. 3112 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3113 CheckConstructor(Constructor); 3114 } else if (CXXDestructorDecl *Destructor = 3115 dyn_cast<CXXDestructorDecl>(NewFD)) { 3116 CXXRecordDecl *Record = Destructor->getParent(); 3117 QualType ClassType = Context.getTypeDeclType(Record); 3118 3119 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3120 // type is dependent? Both gcc and edg can handle that. 3121 if (!ClassType->isDependentType()) { 3122 DeclarationName Name 3123 = Context.DeclarationNames.getCXXDestructorName( 3124 Context.getCanonicalType(ClassType)); 3125 if (NewFD->getDeclName() != Name) { 3126 Diag(NewFD->getLocation(), diag::err_destructor_name); 3127 return NewFD->setInvalidDecl(); 3128 } 3129 3130 CheckDestructor(Destructor); 3131 } 3132 3133 Record->setUserDeclaredDestructor(true); 3134 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3135 // user-defined destructor. 3136 Record->setPOD(false); 3137 3138 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3139 // declared destructor. 3140 // FIXME: C++0x: don't do this for "= default" destructors 3141 Record->setHasTrivialDestructor(false); 3142 } else if (CXXConversionDecl *Conversion 3143 = dyn_cast<CXXConversionDecl>(NewFD)) 3144 ActOnConversionDeclarator(Conversion); 3145 3146 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3147 if (NewFD->isOverloadedOperator() && 3148 CheckOverloadedOperatorDeclaration(NewFD)) 3149 return NewFD->setInvalidDecl(); 3150 3151 // In C++, check default arguments now that we have merged decls. Unless 3152 // the lexical context is the class, because in this case this is done 3153 // during delayed parsing anyway. 3154 if (!CurContext->isRecord()) 3155 CheckCXXDefaultArguments(NewFD); 3156 } 3157} 3158 3159void Sema::CheckMain(FunctionDecl* FD) { 3160 // C++ [basic.start.main]p3: A program that declares main to be inline 3161 // or static is ill-formed. 3162 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3163 // shall not appear in a declaration of main. 3164 // static main is not an error under C99, but we should warn about it. 3165 bool isInline = FD->isInlineSpecified(); 3166 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3167 if (isInline || isStatic) { 3168 unsigned diagID = diag::warn_unusual_main_decl; 3169 if (isInline || getLangOptions().CPlusPlus) 3170 diagID = diag::err_unusual_main_decl; 3171 3172 int which = isStatic + (isInline << 1) - 1; 3173 Diag(FD->getLocation(), diagID) << which; 3174 } 3175 3176 QualType T = FD->getType(); 3177 assert(T->isFunctionType() && "function decl is not of function type"); 3178 const FunctionType* FT = T->getAs<FunctionType>(); 3179 3180 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3181 // TODO: add a replacement fixit to turn the return type into 'int'. 3182 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3183 FD->setInvalidDecl(true); 3184 } 3185 3186 // Treat protoless main() as nullary. 3187 if (isa<FunctionNoProtoType>(FT)) return; 3188 3189 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3190 unsigned nparams = FTP->getNumArgs(); 3191 assert(FD->getNumParams() == nparams); 3192 3193 if (nparams > 3) { 3194 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3195 FD->setInvalidDecl(true); 3196 nparams = 3; 3197 } 3198 3199 // FIXME: a lot of the following diagnostics would be improved 3200 // if we had some location information about types. 3201 3202 QualType CharPP = 3203 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3204 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3205 3206 for (unsigned i = 0; i < nparams; ++i) { 3207 QualType AT = FTP->getArgType(i); 3208 3209 bool mismatch = true; 3210 3211 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3212 mismatch = false; 3213 else if (Expected[i] == CharPP) { 3214 // As an extension, the following forms are okay: 3215 // char const ** 3216 // char const * const * 3217 // char * const * 3218 3219 QualifierCollector qs; 3220 const PointerType* PT; 3221 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3222 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3223 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3224 qs.removeConst(); 3225 mismatch = !qs.empty(); 3226 } 3227 } 3228 3229 if (mismatch) { 3230 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3231 // TODO: suggest replacing given type with expected type 3232 FD->setInvalidDecl(true); 3233 } 3234 } 3235 3236 if (nparams == 1 && !FD->isInvalidDecl()) { 3237 Diag(FD->getLocation(), diag::warn_main_one_arg); 3238 } 3239} 3240 3241bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3242 // FIXME: Need strict checking. In C89, we need to check for 3243 // any assignment, increment, decrement, function-calls, or 3244 // commas outside of a sizeof. In C99, it's the same list, 3245 // except that the aforementioned are allowed in unevaluated 3246 // expressions. Everything else falls under the 3247 // "may accept other forms of constant expressions" exception. 3248 // (We never end up here for C++, so the constant expression 3249 // rules there don't matter.) 3250 if (Init->isConstantInitializer(Context)) 3251 return false; 3252 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3253 << Init->getSourceRange(); 3254 return true; 3255} 3256 3257void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3258 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3259} 3260 3261/// AddInitializerToDecl - Adds the initializer Init to the 3262/// declaration dcl. If DirectInit is true, this is C++ direct 3263/// initialization rather than copy initialization. 3264void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3265 Decl *RealDecl = dcl.getAs<Decl>(); 3266 // If there is no declaration, there was an error parsing it. Just ignore 3267 // the initializer. 3268 if (RealDecl == 0) 3269 return; 3270 3271 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3272 // With declarators parsed the way they are, the parser cannot 3273 // distinguish between a normal initializer and a pure-specifier. 3274 // Thus this grotesque test. 3275 IntegerLiteral *IL; 3276 Expr *Init = static_cast<Expr *>(init.get()); 3277 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3278 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3279 if (Method->isVirtualAsWritten()) { 3280 Method->setPure(); 3281 3282 // A class is abstract if at least one function is pure virtual. 3283 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3284 } else if (!Method->isInvalidDecl()) { 3285 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3286 << Method->getDeclName() << Init->getSourceRange(); 3287 Method->setInvalidDecl(); 3288 } 3289 } else { 3290 Diag(Method->getLocation(), diag::err_member_function_initialization) 3291 << Method->getDeclName() << Init->getSourceRange(); 3292 Method->setInvalidDecl(); 3293 } 3294 return; 3295 } 3296 3297 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3298 if (!VDecl) { 3299 if (getLangOptions().CPlusPlus && 3300 RealDecl->getLexicalDeclContext()->isRecord() && 3301 isa<NamedDecl>(RealDecl)) 3302 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3303 << cast<NamedDecl>(RealDecl)->getDeclName(); 3304 else 3305 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3306 RealDecl->setInvalidDecl(); 3307 return; 3308 } 3309 3310 // A definition must end up with a complete type, which means it must be 3311 // complete with the restriction that an array type might be completed by the 3312 // initializer; note that later code assumes this restriction. 3313 QualType BaseDeclType = VDecl->getType(); 3314 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3315 BaseDeclType = Array->getElementType(); 3316 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3317 diag::err_typecheck_decl_incomplete_type)) { 3318 RealDecl->setInvalidDecl(); 3319 return; 3320 } 3321 3322 const VarDecl *Def = 0; 3323 if (VDecl->getDefinition(Def)) { 3324 Diag(VDecl->getLocation(), diag::err_redefinition) 3325 << VDecl->getDeclName(); 3326 Diag(Def->getLocation(), diag::note_previous_definition); 3327 VDecl->setInvalidDecl(); 3328 return; 3329 } 3330 3331 // Take ownership of the expression, now that we're sure we have somewhere 3332 // to put it. 3333 Expr *Init = init.takeAs<Expr>(); 3334 assert(Init && "missing initializer"); 3335 3336 // Get the decls type and save a reference for later, since 3337 // CheckInitializerTypes may change it. 3338 QualType DclT = VDecl->getType(), SavT = DclT; 3339 if (VDecl->isBlockVarDecl()) { 3340 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3341 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3342 VDecl->setInvalidDecl(); 3343 } else if (!VDecl->isInvalidDecl()) { 3344 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3345 VDecl->getDeclName(), DirectInit)) 3346 VDecl->setInvalidDecl(); 3347 3348 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3349 // Don't check invalid declarations to avoid emitting useless diagnostics. 3350 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3351 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3352 CheckForConstantInitializer(Init, DclT); 3353 } 3354 } 3355 } else if (VDecl->isStaticDataMember() && 3356 VDecl->getLexicalDeclContext()->isRecord()) { 3357 // This is an in-class initialization for a static data member, e.g., 3358 // 3359 // struct S { 3360 // static const int value = 17; 3361 // }; 3362 3363 // Attach the initializer 3364 VDecl->setInit(Context, Init); 3365 3366 // C++ [class.mem]p4: 3367 // A member-declarator can contain a constant-initializer only 3368 // if it declares a static member (9.4) of const integral or 3369 // const enumeration type, see 9.4.2. 3370 QualType T = VDecl->getType(); 3371 if (!T->isDependentType() && 3372 (!Context.getCanonicalType(T).isConstQualified() || 3373 !T->isIntegralType())) { 3374 Diag(VDecl->getLocation(), diag::err_member_initialization) 3375 << VDecl->getDeclName() << Init->getSourceRange(); 3376 VDecl->setInvalidDecl(); 3377 } else { 3378 // C++ [class.static.data]p4: 3379 // If a static data member is of const integral or const 3380 // enumeration type, its declaration in the class definition 3381 // can specify a constant-initializer which shall be an 3382 // integral constant expression (5.19). 3383 if (!Init->isTypeDependent() && 3384 !Init->getType()->isIntegralType()) { 3385 // We have a non-dependent, non-integral or enumeration type. 3386 Diag(Init->getSourceRange().getBegin(), 3387 diag::err_in_class_initializer_non_integral_type) 3388 << Init->getType() << Init->getSourceRange(); 3389 VDecl->setInvalidDecl(); 3390 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3391 // Check whether the expression is a constant expression. 3392 llvm::APSInt Value; 3393 SourceLocation Loc; 3394 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3395 Diag(Loc, diag::err_in_class_initializer_non_constant) 3396 << Init->getSourceRange(); 3397 VDecl->setInvalidDecl(); 3398 } else if (!VDecl->getType()->isDependentType()) 3399 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3400 } 3401 } 3402 } else if (VDecl->isFileVarDecl()) { 3403 if (VDecl->getStorageClass() == VarDecl::Extern) 3404 Diag(VDecl->getLocation(), diag::warn_extern_init); 3405 if (!VDecl->isInvalidDecl()) 3406 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3407 VDecl->getDeclName(), DirectInit)) 3408 VDecl->setInvalidDecl(); 3409 3410 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3411 // Don't check invalid declarations to avoid emitting useless diagnostics. 3412 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3413 // C99 6.7.8p4. All file scoped initializers need to be constant. 3414 CheckForConstantInitializer(Init, DclT); 3415 } 3416 } 3417 // If the type changed, it means we had an incomplete type that was 3418 // completed by the initializer. For example: 3419 // int ary[] = { 1, 3, 5 }; 3420 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3421 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3422 VDecl->setType(DclT); 3423 Init->setType(DclT); 3424 } 3425 3426 Init = MaybeCreateCXXExprWithTemporaries(Init, 3427 /*ShouldDestroyTemporaries=*/true); 3428 // Attach the initializer to the decl. 3429 VDecl->setInit(Context, Init); 3430 3431 // If the previous declaration of VDecl was a tentative definition, 3432 // remove it from the set of tentative definitions. 3433 if (VDecl->getPreviousDeclaration() && 3434 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3435 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3436 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3437 } 3438 3439 return; 3440} 3441 3442void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3443 bool TypeContainsUndeducedAuto) { 3444 Decl *RealDecl = dcl.getAs<Decl>(); 3445 3446 // If there is no declaration, there was an error parsing it. Just ignore it. 3447 if (RealDecl == 0) 3448 return; 3449 3450 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3451 QualType Type = Var->getType(); 3452 3453 // Record tentative definitions. 3454 if (Var->isTentativeDefinition(Context)) { 3455 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3456 InsertPair = 3457 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3458 3459 // Keep the latest definition in the map. If we see 'int i; int i;' we 3460 // want the second one in the map. 3461 InsertPair.first->second = Var; 3462 3463 // However, for the list, we don't care about the order, just make sure 3464 // that there are no dupes for a given declaration name. 3465 if (InsertPair.second) 3466 TentativeDefinitionList.push_back(Var->getDeclName()); 3467 } 3468 3469 // C++ [dcl.init.ref]p3: 3470 // The initializer can be omitted for a reference only in a 3471 // parameter declaration (8.3.5), in the declaration of a 3472 // function return type, in the declaration of a class member 3473 // within its class declaration (9.2), and where the extern 3474 // specifier is explicitly used. 3475 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3476 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3477 << Var->getDeclName() 3478 << SourceRange(Var->getLocation(), Var->getLocation()); 3479 Var->setInvalidDecl(); 3480 return; 3481 } 3482 3483 // C++0x [dcl.spec.auto]p3 3484 if (TypeContainsUndeducedAuto) { 3485 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3486 << Var->getDeclName() << Type; 3487 Var->setInvalidDecl(); 3488 return; 3489 } 3490 3491 // An array without size is an incomplete type, and there are no special 3492 // rules in C++ to make such a definition acceptable. 3493 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3494 !Var->hasExternalStorage()) { 3495 Diag(Var->getLocation(), 3496 diag::err_typecheck_incomplete_array_needs_initializer); 3497 Var->setInvalidDecl(); 3498 return; 3499 } 3500 3501 // C++ [temp.expl.spec]p15: 3502 // An explicit specialization of a static data member of a template is a 3503 // definition if the declaration includes an initializer; otherwise, it 3504 // is a declaration. 3505 if (Var->isStaticDataMember() && 3506 Var->getInstantiatedFromStaticDataMember() && 3507 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3508 return; 3509 3510 // C++ [dcl.init]p9: 3511 // If no initializer is specified for an object, and the object 3512 // is of (possibly cv-qualified) non-POD class type (or array 3513 // thereof), the object shall be default-initialized; if the 3514 // object is of const-qualified type, the underlying class type 3515 // shall have a user-declared default constructor. 3516 // 3517 // FIXME: Diagnose the "user-declared default constructor" bit. 3518 if (getLangOptions().CPlusPlus) { 3519 QualType InitType = Type; 3520 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3521 InitType = Context.getBaseElementType(Array); 3522 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3523 InitType->isRecordType() && !InitType->isDependentType()) { 3524 if (!RequireCompleteType(Var->getLocation(), InitType, 3525 diag::err_invalid_incomplete_type_use)) { 3526 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3527 3528 CXXConstructorDecl *Constructor 3529 = PerformInitializationByConstructor(InitType, 3530 MultiExprArg(*this, 0, 0), 3531 Var->getLocation(), 3532 SourceRange(Var->getLocation(), 3533 Var->getLocation()), 3534 Var->getDeclName(), 3535 IK_Default, 3536 ConstructorArgs); 3537 3538 // FIXME: Location info for the variable initialization? 3539 if (!Constructor) 3540 Var->setInvalidDecl(); 3541 else { 3542 // FIXME: Cope with initialization of arrays 3543 if (!Constructor->isTrivial() && 3544 InitializeVarWithConstructor(Var, Constructor, 3545 move_arg(ConstructorArgs))) 3546 Var->setInvalidDecl(); 3547 3548 FinalizeVarWithDestructor(Var, InitType); 3549 } 3550 } else { 3551 Var->setInvalidDecl(); 3552 } 3553 } 3554 } 3555 3556#if 0 3557 // FIXME: Temporarily disabled because we are not properly parsing 3558 // linkage specifications on declarations, e.g., 3559 // 3560 // extern "C" const CGPoint CGPointerZero; 3561 // 3562 // C++ [dcl.init]p9: 3563 // 3564 // If no initializer is specified for an object, and the 3565 // object is of (possibly cv-qualified) non-POD class type (or 3566 // array thereof), the object shall be default-initialized; if 3567 // the object is of const-qualified type, the underlying class 3568 // type shall have a user-declared default 3569 // constructor. Otherwise, if no initializer is specified for 3570 // an object, the object and its subobjects, if any, have an 3571 // indeterminate initial value; if the object or any of its 3572 // subobjects are of const-qualified type, the program is 3573 // ill-formed. 3574 // 3575 // This isn't technically an error in C, so we don't diagnose it. 3576 // 3577 // FIXME: Actually perform the POD/user-defined default 3578 // constructor check. 3579 if (getLangOptions().CPlusPlus && 3580 Context.getCanonicalType(Type).isConstQualified() && 3581 !Var->hasExternalStorage()) 3582 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3583 << Var->getName() 3584 << SourceRange(Var->getLocation(), Var->getLocation()); 3585#endif 3586 } 3587} 3588 3589Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3590 DeclPtrTy *Group, 3591 unsigned NumDecls) { 3592 llvm::SmallVector<Decl*, 8> Decls; 3593 3594 if (DS.isTypeSpecOwned()) 3595 Decls.push_back((Decl*)DS.getTypeRep()); 3596 3597 for (unsigned i = 0; i != NumDecls; ++i) 3598 if (Decl *D = Group[i].getAs<Decl>()) 3599 Decls.push_back(D); 3600 3601 // Perform semantic analysis that depends on having fully processed both 3602 // the declarator and initializer. 3603 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3604 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3605 if (!IDecl) 3606 continue; 3607 QualType T = IDecl->getType(); 3608 3609 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3610 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3611 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3612 if (T->isDependentType()) { 3613 // If T is dependent, we should not require a complete type. 3614 // (RequireCompleteType shouldn't be called with dependent types.) 3615 // But we still can at least check if we've got an array of unspecified 3616 // size without an initializer. 3617 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3618 !IDecl->getInit()) { 3619 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3620 << T; 3621 IDecl->setInvalidDecl(); 3622 } 3623 } else if (!IDecl->isInvalidDecl()) { 3624 // If T is an incomplete array type with an initializer list that is 3625 // dependent on something, its size has not been fixed. We could attempt 3626 // to fix the size for such arrays, but we would still have to check 3627 // here for initializers containing a C++0x vararg expansion, e.g. 3628 // template <typename... Args> void f(Args... args) { 3629 // int vals[] = { args }; 3630 // } 3631 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3632 Expr *Init = IDecl->getInit(); 3633 if (IAT && Init && 3634 (Init->isTypeDependent() || Init->isValueDependent())) { 3635 // Check that the member type of the array is complete, at least. 3636 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3637 diag::err_typecheck_decl_incomplete_type)) 3638 IDecl->setInvalidDecl(); 3639 } else if (RequireCompleteType(IDecl->getLocation(), T, 3640 diag::err_typecheck_decl_incomplete_type)) 3641 IDecl->setInvalidDecl(); 3642 } 3643 } 3644 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3645 // object that has file scope without an initializer, and without a 3646 // storage-class specifier or with the storage-class specifier "static", 3647 // constitutes a tentative definition. Note: A tentative definition with 3648 // external linkage is valid (C99 6.2.2p5). 3649 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3650 if (const IncompleteArrayType *ArrayT 3651 = Context.getAsIncompleteArrayType(T)) { 3652 if (RequireCompleteType(IDecl->getLocation(), 3653 ArrayT->getElementType(), 3654 diag::err_illegal_decl_array_incomplete_type)) 3655 IDecl->setInvalidDecl(); 3656 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3657 // C99 6.9.2p3: If the declaration of an identifier for an object is 3658 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3659 // declared type shall not be an incomplete type. 3660 // NOTE: code such as the following 3661 // static struct s; 3662 // struct s { int a; }; 3663 // is accepted by gcc. Hence here we issue a warning instead of 3664 // an error and we do not invalidate the static declaration. 3665 // NOTE: to avoid multiple warnings, only check the first declaration. 3666 if (IDecl->getPreviousDeclaration() == 0) 3667 RequireCompleteType(IDecl->getLocation(), T, 3668 diag::ext_typecheck_decl_incomplete_type); 3669 } 3670 } 3671 } 3672 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3673 Decls.data(), Decls.size())); 3674} 3675 3676 3677/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3678/// to introduce parameters into function prototype scope. 3679Sema::DeclPtrTy 3680Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3681 const DeclSpec &DS = D.getDeclSpec(); 3682 3683 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3684 VarDecl::StorageClass StorageClass = VarDecl::None; 3685 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3686 StorageClass = VarDecl::Register; 3687 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3688 Diag(DS.getStorageClassSpecLoc(), 3689 diag::err_invalid_storage_class_in_func_decl); 3690 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3691 } 3692 3693 if (D.getDeclSpec().isThreadSpecified()) 3694 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3695 3696 DiagnoseFunctionSpecifiers(D); 3697 3698 // Check that there are no default arguments inside the type of this 3699 // parameter (C++ only). 3700 if (getLangOptions().CPlusPlus) 3701 CheckExtraCXXDefaultArguments(D); 3702 3703 DeclaratorInfo *DInfo = 0; 3704 TagDecl *OwnedDecl = 0; 3705 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3706 3707 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3708 // C++ [dcl.fct]p6: 3709 // Types shall not be defined in return or parameter types. 3710 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3711 << Context.getTypeDeclType(OwnedDecl); 3712 } 3713 3714 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3715 // Can this happen for params? We already checked that they don't conflict 3716 // among each other. Here they can only shadow globals, which is ok. 3717 IdentifierInfo *II = D.getIdentifier(); 3718 if (II) { 3719 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3720 if (PrevDecl->isTemplateParameter()) { 3721 // Maybe we will complain about the shadowed template parameter. 3722 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3723 // Just pretend that we didn't see the previous declaration. 3724 PrevDecl = 0; 3725 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3726 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3727 3728 // Recover by removing the name 3729 II = 0; 3730 D.SetIdentifier(0, D.getIdentifierLoc()); 3731 } 3732 } 3733 } 3734 3735 // Parameters can not be abstract class types. 3736 // For record types, this is done by the AbstractClassUsageDiagnoser once 3737 // the class has been completely parsed. 3738 if (!CurContext->isRecord() && 3739 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3740 diag::err_abstract_type_in_decl, 3741 AbstractParamType)) 3742 D.setInvalidType(true); 3743 3744 QualType T = adjustParameterType(parmDeclType); 3745 3746 ParmVarDecl *New 3747 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3748 T, DInfo, StorageClass, 0); 3749 3750 if (D.isInvalidType()) 3751 New->setInvalidDecl(); 3752 3753 // Parameter declarators cannot be interface types. All ObjC objects are 3754 // passed by reference. 3755 if (T->isObjCInterfaceType()) { 3756 Diag(D.getIdentifierLoc(), 3757 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3758 New->setInvalidDecl(); 3759 } 3760 3761 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3762 if (D.getCXXScopeSpec().isSet()) { 3763 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3764 << D.getCXXScopeSpec().getRange(); 3765 New->setInvalidDecl(); 3766 } 3767 3768 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3769 // duration shall not be qualified by an address-space qualifier." 3770 // Since all parameters have automatic store duration, they can not have 3771 // an address space. 3772 if (T.getAddressSpace() != 0) { 3773 Diag(D.getIdentifierLoc(), 3774 diag::err_arg_with_address_space); 3775 New->setInvalidDecl(); 3776 } 3777 3778 3779 // Add the parameter declaration into this scope. 3780 S->AddDecl(DeclPtrTy::make(New)); 3781 if (II) 3782 IdResolver.AddDecl(New); 3783 3784 ProcessDeclAttributes(S, New, D); 3785 3786 if (New->hasAttr<BlocksAttr>()) { 3787 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3788 } 3789 return DeclPtrTy::make(New); 3790} 3791 3792void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3793 SourceLocation LocAfterDecls) { 3794 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3795 "Not a function declarator!"); 3796 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3797 3798 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3799 // for a K&R function. 3800 if (!FTI.hasPrototype) { 3801 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3802 --i; 3803 if (FTI.ArgInfo[i].Param == 0) { 3804 llvm::SmallString<256> Code; 3805 llvm::raw_svector_ostream(Code) << " int " 3806 << FTI.ArgInfo[i].Ident->getName() 3807 << ";\n"; 3808 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3809 << FTI.ArgInfo[i].Ident 3810 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3811 3812 // Implicitly declare the argument as type 'int' for lack of a better 3813 // type. 3814 DeclSpec DS; 3815 const char* PrevSpec; // unused 3816 unsigned DiagID; // unused 3817 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3818 PrevSpec, DiagID); 3819 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3820 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3821 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3822 } 3823 } 3824 } 3825} 3826 3827Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3828 Declarator &D) { 3829 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3830 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3831 "Not a function declarator!"); 3832 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3833 3834 if (FTI.hasPrototype) { 3835 // FIXME: Diagnose arguments without names in C. 3836 } 3837 3838 Scope *ParentScope = FnBodyScope->getParent(); 3839 3840 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3841 MultiTemplateParamsArg(*this), 3842 /*IsFunctionDefinition=*/true); 3843 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3844} 3845 3846Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3847 // Clear the last template instantiation error context. 3848 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 3849 3850 if (!D) 3851 return D; 3852 FunctionDecl *FD = 0; 3853 3854 if (FunctionTemplateDecl *FunTmpl 3855 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3856 FD = FunTmpl->getTemplatedDecl(); 3857 else 3858 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3859 3860 CurFunctionNeedsScopeChecking = false; 3861 3862 // See if this is a redefinition. 3863 const FunctionDecl *Definition; 3864 if (FD->getBody(Definition)) { 3865 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3866 Diag(Definition->getLocation(), diag::note_previous_definition); 3867 } 3868 3869 // Builtin functions cannot be defined. 3870 if (unsigned BuiltinID = FD->getBuiltinID()) { 3871 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3872 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3873 FD->setInvalidDecl(); 3874 } 3875 } 3876 3877 // The return type of a function definition must be complete 3878 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3879 QualType ResultType = FD->getResultType(); 3880 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3881 !FD->isInvalidDecl() && 3882 RequireCompleteType(FD->getLocation(), ResultType, 3883 diag::err_func_def_incomplete_result)) 3884 FD->setInvalidDecl(); 3885 3886 // GNU warning -Wmissing-prototypes: 3887 // Warn if a global function is defined without a previous 3888 // prototype declaration. This warning is issued even if the 3889 // definition itself provides a prototype. The aim is to detect 3890 // global functions that fail to be declared in header files. 3891 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3892 !FD->isMain()) { 3893 bool MissingPrototype = true; 3894 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3895 Prev; Prev = Prev->getPreviousDeclaration()) { 3896 // Ignore any declarations that occur in function or method 3897 // scope, because they aren't visible from the header. 3898 if (Prev->getDeclContext()->isFunctionOrMethod()) 3899 continue; 3900 3901 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3902 break; 3903 } 3904 3905 if (MissingPrototype) 3906 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3907 } 3908 3909 if (FnBodyScope) 3910 PushDeclContext(FnBodyScope, FD); 3911 3912 // Check the validity of our function parameters 3913 CheckParmsForFunctionDef(FD); 3914 3915 // Introduce our parameters into the function scope 3916 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3917 ParmVarDecl *Param = FD->getParamDecl(p); 3918 Param->setOwningFunction(FD); 3919 3920 // If this has an identifier, add it to the scope stack. 3921 if (Param->getIdentifier() && FnBodyScope) 3922 PushOnScopeChains(Param, FnBodyScope); 3923 } 3924 3925 // Checking attributes of current function definition 3926 // dllimport attribute. 3927 if (FD->getAttr<DLLImportAttr>() && 3928 (!FD->getAttr<DLLExportAttr>())) { 3929 // dllimport attribute cannot be applied to definition. 3930 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3931 Diag(FD->getLocation(), 3932 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3933 << "dllimport"; 3934 FD->setInvalidDecl(); 3935 return DeclPtrTy::make(FD); 3936 } else { 3937 // If a symbol previously declared dllimport is later defined, the 3938 // attribute is ignored in subsequent references, and a warning is 3939 // emitted. 3940 Diag(FD->getLocation(), 3941 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3942 << FD->getNameAsCString() << "dllimport"; 3943 } 3944 } 3945 return DeclPtrTy::make(FD); 3946} 3947 3948Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3949 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3950} 3951 3952Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3953 bool IsInstantiation) { 3954 Decl *dcl = D.getAs<Decl>(); 3955 Stmt *Body = BodyArg.takeAs<Stmt>(); 3956 3957 FunctionDecl *FD = 0; 3958 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3959 if (FunTmpl) 3960 FD = FunTmpl->getTemplatedDecl(); 3961 else 3962 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3963 3964 if (FD) { 3965 FD->setBody(Body); 3966 if (FD->isMain()) 3967 // C and C++ allow for main to automagically return 0. 3968 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3969 FD->setHasImplicitReturnZero(true); 3970 else 3971 CheckFallThroughForFunctionDef(FD, Body); 3972 3973 if (!FD->isInvalidDecl()) 3974 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3975 3976 // C++ [basic.def.odr]p2: 3977 // [...] A virtual member function is used if it is not pure. [...] 3978 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3979 if (Method->isVirtual() && !Method->isPure()) 3980 MarkDeclarationReferenced(Method->getLocation(), Method); 3981 3982 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3983 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3984 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3985 MD->setBody(Body); 3986 CheckFallThroughForFunctionDef(MD, Body); 3987 MD->setEndLoc(Body->getLocEnd()); 3988 3989 if (!MD->isInvalidDecl()) 3990 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3991 } else { 3992 Body->Destroy(Context); 3993 return DeclPtrTy(); 3994 } 3995 if (!IsInstantiation) 3996 PopDeclContext(); 3997 3998 // Verify and clean out per-function state. 3999 4000 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4001 4002 // Check goto/label use. 4003 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4004 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4005 LabelStmt *L = I->second; 4006 4007 // Verify that we have no forward references left. If so, there was a goto 4008 // or address of a label taken, but no definition of it. Label fwd 4009 // definitions are indicated with a null substmt. 4010 if (L->getSubStmt() != 0) 4011 continue; 4012 4013 // Emit error. 4014 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4015 4016 // At this point, we have gotos that use the bogus label. Stitch it into 4017 // the function body so that they aren't leaked and that the AST is well 4018 // formed. 4019 if (Body == 0) { 4020 // The whole function wasn't parsed correctly, just delete this. 4021 L->Destroy(Context); 4022 continue; 4023 } 4024 4025 // Otherwise, the body is valid: we want to stitch the label decl into the 4026 // function somewhere so that it is properly owned and so that the goto 4027 // has a valid target. Do this by creating a new compound stmt with the 4028 // label in it. 4029 4030 // Give the label a sub-statement. 4031 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4032 4033 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4034 cast<CXXTryStmt>(Body)->getTryBlock() : 4035 cast<CompoundStmt>(Body); 4036 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4037 Elements.push_back(L); 4038 Compound->setStmts(Context, &Elements[0], Elements.size()); 4039 } 4040 FunctionLabelMap.clear(); 4041 4042 if (!Body) return D; 4043 4044 // Verify that that gotos and switch cases don't jump into scopes illegally. 4045 if (CurFunctionNeedsScopeChecking) 4046 DiagnoseInvalidJumps(Body); 4047 4048 // C++ constructors that have function-try-blocks can't have return 4049 // statements in the handlers of that block. (C++ [except.handle]p14) 4050 // Verify this. 4051 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4052 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4053 4054 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4055 computeBaseOrMembersToDestroy(Destructor); 4056 4057 // If any errors have occurred, clear out any temporaries that may have 4058 // been leftover. This ensures that these temporaries won't be picked up for 4059 // deletion in some later function. 4060 if (PP.getDiagnostics().hasErrorOccurred()) 4061 ExprTemporaries.clear(); 4062 4063 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4064 return D; 4065} 4066 4067/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4068/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4069NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4070 IdentifierInfo &II, Scope *S) { 4071 // Before we produce a declaration for an implicitly defined 4072 // function, see whether there was a locally-scoped declaration of 4073 // this name as a function or variable. If so, use that 4074 // (non-visible) declaration, and complain about it. 4075 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4076 = LocallyScopedExternalDecls.find(&II); 4077 if (Pos != LocallyScopedExternalDecls.end()) { 4078 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4079 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4080 return Pos->second; 4081 } 4082 4083 // Extension in C99. Legal in C90, but warn about it. 4084 if (II.getName().startswith("__builtin_")) 4085 Diag(Loc, diag::warn_builtin_unknown) << &II; 4086 else if (getLangOptions().C99) 4087 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4088 else 4089 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4090 4091 // Set a Declarator for the implicit definition: int foo(); 4092 const char *Dummy; 4093 DeclSpec DS; 4094 unsigned DiagID; 4095 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4096 Error = Error; // Silence warning. 4097 assert(!Error && "Error setting up implicit decl!"); 4098 Declarator D(DS, Declarator::BlockContext); 4099 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4100 0, 0, false, SourceLocation(), 4101 false, 0,0,0, Loc, Loc, D), 4102 SourceLocation()); 4103 D.SetIdentifier(&II, Loc); 4104 4105 // Insert this function into translation-unit scope. 4106 4107 DeclContext *PrevDC = CurContext; 4108 CurContext = Context.getTranslationUnitDecl(); 4109 4110 FunctionDecl *FD = 4111 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4112 FD->setImplicit(); 4113 4114 CurContext = PrevDC; 4115 4116 AddKnownFunctionAttributes(FD); 4117 4118 return FD; 4119} 4120 4121/// \brief Adds any function attributes that we know a priori based on 4122/// the declaration of this function. 4123/// 4124/// These attributes can apply both to implicitly-declared builtins 4125/// (like __builtin___printf_chk) or to library-declared functions 4126/// like NSLog or printf. 4127void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4128 if (FD->isInvalidDecl()) 4129 return; 4130 4131 // If this is a built-in function, map its builtin attributes to 4132 // actual attributes. 4133 if (unsigned BuiltinID = FD->getBuiltinID()) { 4134 // Handle printf-formatting attributes. 4135 unsigned FormatIdx; 4136 bool HasVAListArg; 4137 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4138 if (!FD->getAttr<FormatAttr>()) 4139 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4140 HasVAListArg ? 0 : FormatIdx + 2)); 4141 } 4142 4143 // Mark const if we don't care about errno and that is the only 4144 // thing preventing the function from being const. This allows 4145 // IRgen to use LLVM intrinsics for such functions. 4146 if (!getLangOptions().MathErrno && 4147 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4148 if (!FD->getAttr<ConstAttr>()) 4149 FD->addAttr(::new (Context) ConstAttr()); 4150 } 4151 4152 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4153 FD->addAttr(::new (Context) NoReturnAttr()); 4154 } 4155 4156 IdentifierInfo *Name = FD->getIdentifier(); 4157 if (!Name) 4158 return; 4159 if ((!getLangOptions().CPlusPlus && 4160 FD->getDeclContext()->isTranslationUnit()) || 4161 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4162 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4163 LinkageSpecDecl::lang_c)) { 4164 // Okay: this could be a libc/libm/Objective-C function we know 4165 // about. 4166 } else 4167 return; 4168 4169 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4170 // FIXME: NSLog and NSLogv should be target specific 4171 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4172 // FIXME: We known better than our headers. 4173 const_cast<FormatAttr *>(Format)->setType("printf"); 4174 } else 4175 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4176 Name->isStr("NSLogv") ? 0 : 2)); 4177 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4178 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4179 // target-specific builtins, perhaps? 4180 if (!FD->getAttr<FormatAttr>()) 4181 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4182 Name->isStr("vasprintf") ? 0 : 3)); 4183 } 4184} 4185 4186TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4187 DeclaratorInfo *DInfo) { 4188 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4189 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4190 4191 if (!DInfo) { 4192 assert(D.isInvalidType() && "no declarator info for valid type"); 4193 DInfo = Context.getTrivialDeclaratorInfo(T); 4194 } 4195 4196 // Scope manipulation handled by caller. 4197 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4198 D.getIdentifierLoc(), 4199 D.getIdentifier(), 4200 DInfo); 4201 4202 if (const TagType *TT = T->getAs<TagType>()) { 4203 TagDecl *TD = TT->getDecl(); 4204 4205 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4206 // keep track of the TypedefDecl. 4207 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4208 TD->setTypedefForAnonDecl(NewTD); 4209 } 4210 4211 if (D.isInvalidType()) 4212 NewTD->setInvalidDecl(); 4213 return NewTD; 4214} 4215 4216 4217/// \brief Determine whether a tag with a given kind is acceptable 4218/// as a redeclaration of the given tag declaration. 4219/// 4220/// \returns true if the new tag kind is acceptable, false otherwise. 4221bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4222 TagDecl::TagKind NewTag, 4223 SourceLocation NewTagLoc, 4224 const IdentifierInfo &Name) { 4225 // C++ [dcl.type.elab]p3: 4226 // The class-key or enum keyword present in the 4227 // elaborated-type-specifier shall agree in kind with the 4228 // declaration to which the name in theelaborated-type-specifier 4229 // refers. This rule also applies to the form of 4230 // elaborated-type-specifier that declares a class-name or 4231 // friend class since it can be construed as referring to the 4232 // definition of the class. Thus, in any 4233 // elaborated-type-specifier, the enum keyword shall be used to 4234 // refer to an enumeration (7.2), the union class-keyshall be 4235 // used to refer to a union (clause 9), and either the class or 4236 // struct class-key shall be used to refer to a class (clause 9) 4237 // declared using the class or struct class-key. 4238 TagDecl::TagKind OldTag = Previous->getTagKind(); 4239 if (OldTag == NewTag) 4240 return true; 4241 4242 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4243 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4244 // Warn about the struct/class tag mismatch. 4245 bool isTemplate = false; 4246 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4247 isTemplate = Record->getDescribedClassTemplate(); 4248 4249 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4250 << (NewTag == TagDecl::TK_class) 4251 << isTemplate << &Name 4252 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4253 OldTag == TagDecl::TK_class? "class" : "struct"); 4254 Diag(Previous->getLocation(), diag::note_previous_use); 4255 return true; 4256 } 4257 return false; 4258} 4259 4260/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4261/// former case, Name will be non-null. In the later case, Name will be null. 4262/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4263/// reference/declaration/definition of a tag. 4264Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4265 SourceLocation KWLoc, const CXXScopeSpec &SS, 4266 IdentifierInfo *Name, SourceLocation NameLoc, 4267 AttributeList *Attr, AccessSpecifier AS, 4268 MultiTemplateParamsArg TemplateParameterLists, 4269 bool &OwnedDecl, bool &IsDependent) { 4270 // If this is not a definition, it must have a name. 4271 assert((Name != 0 || TUK == TUK_Definition) && 4272 "Nameless record must be a definition!"); 4273 4274 OwnedDecl = false; 4275 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4276 4277 // FIXME: Check explicit specializations more carefully. 4278 bool isExplicitSpecialization = false; 4279 if (TUK != TUK_Reference) { 4280 if (TemplateParameterList *TemplateParams 4281 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4282 (TemplateParameterList**)TemplateParameterLists.get(), 4283 TemplateParameterLists.size(), 4284 isExplicitSpecialization)) { 4285 if (TemplateParams->size() > 0) { 4286 // This is a declaration or definition of a class template (which may 4287 // be a member of another template). 4288 OwnedDecl = false; 4289 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4290 SS, Name, NameLoc, Attr, 4291 TemplateParams, 4292 AS); 4293 TemplateParameterLists.release(); 4294 return Result.get(); 4295 } else { 4296 // The "template<>" header is extraneous. 4297 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4298 << ElaboratedType::getNameForTagKind(Kind) << Name; 4299 isExplicitSpecialization = true; 4300 } 4301 } 4302 4303 TemplateParameterLists.release(); 4304 } 4305 4306 DeclContext *SearchDC = CurContext; 4307 DeclContext *DC = CurContext; 4308 NamedDecl *PrevDecl = 0; 4309 bool isStdBadAlloc = false; 4310 bool Invalid = false; 4311 4312 LookupResult::RedeclarationKind Redecl = 4313 (LookupResult::RedeclarationKind) (TUK != TUK_Reference); 4314 4315 if (Name && SS.isNotEmpty()) { 4316 // We have a nested-name tag ('struct foo::bar'). 4317 4318 // Check for invalid 'foo::'. 4319 if (SS.isInvalid()) { 4320 Name = 0; 4321 goto CreateNewDecl; 4322 } 4323 4324 // If this is a friend or a reference to a class in a dependent 4325 // context, don't try to make a decl for it. 4326 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4327 DC = computeDeclContext(SS, false); 4328 if (!DC) { 4329 IsDependent = true; 4330 return DeclPtrTy(); 4331 } 4332 } 4333 4334 if (RequireCompleteDeclContext(SS)) 4335 return DeclPtrTy::make((Decl *)0); 4336 4337 DC = computeDeclContext(SS, true); 4338 SearchDC = DC; 4339 // Look-up name inside 'foo::'. 4340 LookupResult R(*this, Name, NameLoc, LookupTagName, Redecl); 4341 LookupQualifiedName(R, DC); 4342 4343 if (R.isAmbiguous()) 4344 return DeclPtrTy(); 4345 4346 if (R.getResultKind() == LookupResult::Found) 4347 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4348 4349 // A tag 'foo::bar' must already exist. 4350 if (!PrevDecl) { 4351 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4352 Name = 0; 4353 Invalid = true; 4354 goto CreateNewDecl; 4355 } 4356 } else if (Name) { 4357 // If this is a named struct, check to see if there was a previous forward 4358 // declaration or definition. 4359 // FIXME: We're looking into outer scopes here, even when we 4360 // shouldn't be. Doing so can result in ambiguities that we 4361 // shouldn't be diagnosing. 4362 LookupResult R(*this, Name, NameLoc, LookupTagName, Redecl); 4363 LookupName(R, S); 4364 if (R.isAmbiguous()) { 4365 // FIXME: This is not best way to recover from case like: 4366 // 4367 // struct S s; 4368 // 4369 // causes needless "incomplete type" error later. 4370 Name = 0; 4371 PrevDecl = 0; 4372 Invalid = true; 4373 } else 4374 PrevDecl = R.getAsSingleDecl(Context); 4375 4376 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4377 // FIXME: This makes sure that we ignore the contexts associated 4378 // with C structs, unions, and enums when looking for a matching 4379 // tag declaration or definition. See the similar lookup tweak 4380 // in Sema::LookupName; is there a better way to deal with this? 4381 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4382 SearchDC = SearchDC->getParent(); 4383 } 4384 } 4385 4386 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4387 // Maybe we will complain about the shadowed template parameter. 4388 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4389 // Just pretend that we didn't see the previous declaration. 4390 PrevDecl = 0; 4391 } 4392 4393 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4394 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4395 // This is a declaration of or a reference to "std::bad_alloc". 4396 isStdBadAlloc = true; 4397 4398 if (!PrevDecl && StdBadAlloc) { 4399 // std::bad_alloc has been implicitly declared (but made invisible to 4400 // name lookup). Fill in this implicit declaration as the previous 4401 // declaration, so that the declarations get chained appropriately. 4402 PrevDecl = StdBadAlloc; 4403 } 4404 } 4405 4406 if (PrevDecl) { 4407 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4408 // If this is a use of a previous tag, or if the tag is already declared 4409 // in the same scope (so that the definition/declaration completes or 4410 // rementions the tag), reuse the decl. 4411 if (TUK == TUK_Reference || TUK == TUK_Friend || 4412 isDeclInScope(PrevDecl, SearchDC, S)) { 4413 // Make sure that this wasn't declared as an enum and now used as a 4414 // struct or something similar. 4415 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4416 bool SafeToContinue 4417 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4418 Kind != TagDecl::TK_enum); 4419 if (SafeToContinue) 4420 Diag(KWLoc, diag::err_use_with_wrong_tag) 4421 << Name 4422 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4423 PrevTagDecl->getKindName()); 4424 else 4425 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4426 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4427 4428 if (SafeToContinue) 4429 Kind = PrevTagDecl->getTagKind(); 4430 else { 4431 // Recover by making this an anonymous redefinition. 4432 Name = 0; 4433 PrevDecl = 0; 4434 Invalid = true; 4435 } 4436 } 4437 4438 if (!Invalid) { 4439 // If this is a use, just return the declaration we found. 4440 4441 // FIXME: In the future, return a variant or some other clue 4442 // for the consumer of this Decl to know it doesn't own it. 4443 // For our current ASTs this shouldn't be a problem, but will 4444 // need to be changed with DeclGroups. 4445 if (TUK == TUK_Reference || TUK == TUK_Friend) 4446 return DeclPtrTy::make(PrevDecl); 4447 4448 // Diagnose attempts to redefine a tag. 4449 if (TUK == TUK_Definition) { 4450 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4451 // If we're defining a specialization and the previous definition 4452 // is from an implicit instantiation, don't emit an error 4453 // here; we'll catch this in the general case below. 4454 if (!isExplicitSpecialization || 4455 !isa<CXXRecordDecl>(Def) || 4456 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4457 == TSK_ExplicitSpecialization) { 4458 Diag(NameLoc, diag::err_redefinition) << Name; 4459 Diag(Def->getLocation(), diag::note_previous_definition); 4460 // If this is a redefinition, recover by making this 4461 // struct be anonymous, which will make any later 4462 // references get the previous definition. 4463 Name = 0; 4464 PrevDecl = 0; 4465 Invalid = true; 4466 } 4467 } else { 4468 // If the type is currently being defined, complain 4469 // about a nested redefinition. 4470 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4471 if (Tag->isBeingDefined()) { 4472 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4473 Diag(PrevTagDecl->getLocation(), 4474 diag::note_previous_definition); 4475 Name = 0; 4476 PrevDecl = 0; 4477 Invalid = true; 4478 } 4479 } 4480 4481 // Okay, this is definition of a previously declared or referenced 4482 // tag PrevDecl. We're going to create a new Decl for it. 4483 } 4484 } 4485 // If we get here we have (another) forward declaration or we 4486 // have a definition. Just create a new decl. 4487 4488 } else { 4489 // If we get here, this is a definition of a new tag type in a nested 4490 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4491 // new decl/type. We set PrevDecl to NULL so that the entities 4492 // have distinct types. 4493 PrevDecl = 0; 4494 } 4495 // If we get here, we're going to create a new Decl. If PrevDecl 4496 // is non-NULL, it's a definition of the tag declared by 4497 // PrevDecl. If it's NULL, we have a new definition. 4498 } else { 4499 // PrevDecl is a namespace, template, or anything else 4500 // that lives in the IDNS_Tag identifier namespace. 4501 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4502 // The tag name clashes with a namespace name, issue an error and 4503 // recover by making this tag be anonymous. 4504 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4505 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4506 Name = 0; 4507 PrevDecl = 0; 4508 Invalid = true; 4509 } else { 4510 // The existing declaration isn't relevant to us; we're in a 4511 // new scope, so clear out the previous declaration. 4512 PrevDecl = 0; 4513 } 4514 } 4515 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4516 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4517 // C++ [basic.scope.pdecl]p5: 4518 // -- for an elaborated-type-specifier of the form 4519 // 4520 // class-key identifier 4521 // 4522 // if the elaborated-type-specifier is used in the 4523 // decl-specifier-seq or parameter-declaration-clause of a 4524 // function defined in namespace scope, the identifier is 4525 // declared as a class-name in the namespace that contains 4526 // the declaration; otherwise, except as a friend 4527 // declaration, the identifier is declared in the smallest 4528 // non-class, non-function-prototype scope that contains the 4529 // declaration. 4530 // 4531 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4532 // C structs and unions. 4533 // 4534 // GNU C also supports this behavior as part of its incomplete 4535 // enum types extension, while GNU C++ does not. 4536 // 4537 // Find the context where we'll be declaring the tag. 4538 // FIXME: We would like to maintain the current DeclContext as the 4539 // lexical context, 4540 while (SearchDC->isRecord()) 4541 SearchDC = SearchDC->getParent(); 4542 4543 // Find the scope where we'll be declaring the tag. 4544 while (S->isClassScope() || 4545 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4546 ((S->getFlags() & Scope::DeclScope) == 0) || 4547 (S->getEntity() && 4548 ((DeclContext *)S->getEntity())->isTransparentContext())) 4549 S = S->getParent(); 4550 4551 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4552 // C++ [namespace.memdef]p3: 4553 // If a friend declaration in a non-local class first declares a 4554 // class or function, the friend class or function is a member of 4555 // the innermost enclosing namespace. 4556 while (!SearchDC->isFileContext()) 4557 SearchDC = SearchDC->getParent(); 4558 4559 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4560 while (S->getEntity() != SearchDC) 4561 S = S->getParent(); 4562 } 4563 4564CreateNewDecl: 4565 4566 // If there is an identifier, use the location of the identifier as the 4567 // location of the decl, otherwise use the location of the struct/union 4568 // keyword. 4569 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4570 4571 // Otherwise, create a new declaration. If there is a previous 4572 // declaration of the same entity, the two will be linked via 4573 // PrevDecl. 4574 TagDecl *New; 4575 4576 if (Kind == TagDecl::TK_enum) { 4577 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4578 // enum X { A, B, C } D; D should chain to X. 4579 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4580 cast_or_null<EnumDecl>(PrevDecl)); 4581 // If this is an undefined enum, warn. 4582 if (TUK != TUK_Definition && !Invalid) { 4583 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4584 : diag::ext_forward_ref_enum; 4585 Diag(Loc, DK); 4586 } 4587 } else { 4588 // struct/union/class 4589 4590 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4591 // struct X { int A; } D; D should chain to X. 4592 if (getLangOptions().CPlusPlus) { 4593 // FIXME: Look for a way to use RecordDecl for simple structs. 4594 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4595 cast_or_null<CXXRecordDecl>(PrevDecl)); 4596 4597 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4598 StdBadAlloc = cast<CXXRecordDecl>(New); 4599 } else 4600 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4601 cast_or_null<RecordDecl>(PrevDecl)); 4602 } 4603 4604 if (Kind != TagDecl::TK_enum) { 4605 // Handle #pragma pack: if the #pragma pack stack has non-default 4606 // alignment, make up a packed attribute for this decl. These 4607 // attributes are checked when the ASTContext lays out the 4608 // structure. 4609 // 4610 // It is important for implementing the correct semantics that this 4611 // happen here (in act on tag decl). The #pragma pack stack is 4612 // maintained as a result of parser callbacks which can occur at 4613 // many points during the parsing of a struct declaration (because 4614 // the #pragma tokens are effectively skipped over during the 4615 // parsing of the struct). 4616 if (unsigned Alignment = getPragmaPackAlignment()) 4617 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4618 } 4619 4620 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4621 // C++ [dcl.typedef]p3: 4622 // [...] Similarly, in a given scope, a class or enumeration 4623 // shall not be declared with the same name as a typedef-name 4624 // that is declared in that scope and refers to a type other 4625 // than the class or enumeration itself. 4626 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4627 LookupResult::ForRedeclaration); 4628 LookupName(Lookup, S); 4629 TypedefDecl *PrevTypedef = 0; 4630 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4631 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4632 4633 NamedDecl *PrevTypedefNamed = PrevTypedef; 4634 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4635 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4636 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4637 Diag(Loc, diag::err_tag_definition_of_typedef) 4638 << Context.getTypeDeclType(New) 4639 << PrevTypedef->getUnderlyingType(); 4640 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4641 Invalid = true; 4642 } 4643 } 4644 4645 // If this is a specialization of a member class (of a class template), 4646 // check the specialization. 4647 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4648 Invalid = true; 4649 4650 if (Invalid) 4651 New->setInvalidDecl(); 4652 4653 if (Attr) 4654 ProcessDeclAttributeList(S, New, Attr); 4655 4656 // If we're declaring or defining a tag in function prototype scope 4657 // in C, note that this type can only be used within the function. 4658 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4659 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4660 4661 // Set the lexical context. If the tag has a C++ scope specifier, the 4662 // lexical context will be different from the semantic context. 4663 New->setLexicalDeclContext(CurContext); 4664 4665 // Mark this as a friend decl if applicable. 4666 if (TUK == TUK_Friend) 4667 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4668 4669 // Set the access specifier. 4670 if (!Invalid && TUK != TUK_Friend) 4671 SetMemberAccessSpecifier(New, PrevDecl, AS); 4672 4673 if (TUK == TUK_Definition) 4674 New->startDefinition(); 4675 4676 // If this has an identifier, add it to the scope stack. 4677 if (TUK == TUK_Friend) { 4678 // We might be replacing an existing declaration in the lookup tables; 4679 // if so, borrow its access specifier. 4680 if (PrevDecl) 4681 New->setAccess(PrevDecl->getAccess()); 4682 4683 // Friend tag decls are visible in fairly strange ways. 4684 if (!CurContext->isDependentContext()) { 4685 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4686 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4687 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4688 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4689 } 4690 } else if (Name) { 4691 S = getNonFieldDeclScope(S); 4692 PushOnScopeChains(New, S); 4693 } else { 4694 CurContext->addDecl(New); 4695 } 4696 4697 // If this is the C FILE type, notify the AST context. 4698 if (IdentifierInfo *II = New->getIdentifier()) 4699 if (!New->isInvalidDecl() && 4700 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4701 II->isStr("FILE")) 4702 Context.setFILEDecl(New); 4703 4704 OwnedDecl = true; 4705 return DeclPtrTy::make(New); 4706} 4707 4708void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4709 AdjustDeclIfTemplate(TagD); 4710 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4711 4712 // Enter the tag context. 4713 PushDeclContext(S, Tag); 4714 4715 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4716 FieldCollector->StartClass(); 4717 4718 if (Record->getIdentifier()) { 4719 // C++ [class]p2: 4720 // [...] The class-name is also inserted into the scope of the 4721 // class itself; this is known as the injected-class-name. For 4722 // purposes of access checking, the injected-class-name is treated 4723 // as if it were a public member name. 4724 CXXRecordDecl *InjectedClassName 4725 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4726 CurContext, Record->getLocation(), 4727 Record->getIdentifier(), 4728 Record->getTagKeywordLoc(), 4729 Record); 4730 InjectedClassName->setImplicit(); 4731 InjectedClassName->setAccess(AS_public); 4732 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4733 InjectedClassName->setDescribedClassTemplate(Template); 4734 PushOnScopeChains(InjectedClassName, S); 4735 assert(InjectedClassName->isInjectedClassName() && 4736 "Broken injected-class-name"); 4737 } 4738 } 4739} 4740 4741void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4742 SourceLocation RBraceLoc) { 4743 AdjustDeclIfTemplate(TagD); 4744 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4745 Tag->setRBraceLoc(RBraceLoc); 4746 4747 if (isa<CXXRecordDecl>(Tag)) 4748 FieldCollector->FinishClass(); 4749 4750 // Exit this scope of this tag's definition. 4751 PopDeclContext(); 4752 4753 // Notify the consumer that we've defined a tag. 4754 Consumer.HandleTagDeclDefinition(Tag); 4755} 4756 4757// Note that FieldName may be null for anonymous bitfields. 4758bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4759 QualType FieldTy, const Expr *BitWidth, 4760 bool *ZeroWidth) { 4761 // Default to true; that shouldn't confuse checks for emptiness 4762 if (ZeroWidth) 4763 *ZeroWidth = true; 4764 4765 // C99 6.7.2.1p4 - verify the field type. 4766 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4767 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4768 // Handle incomplete types with specific error. 4769 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4770 return true; 4771 if (FieldName) 4772 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4773 << FieldName << FieldTy << BitWidth->getSourceRange(); 4774 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4775 << FieldTy << BitWidth->getSourceRange(); 4776 } 4777 4778 // If the bit-width is type- or value-dependent, don't try to check 4779 // it now. 4780 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4781 return false; 4782 4783 llvm::APSInt Value; 4784 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4785 return true; 4786 4787 if (Value != 0 && ZeroWidth) 4788 *ZeroWidth = false; 4789 4790 // Zero-width bitfield is ok for anonymous field. 4791 if (Value == 0 && FieldName) 4792 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4793 4794 if (Value.isSigned() && Value.isNegative()) { 4795 if (FieldName) 4796 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4797 << FieldName << Value.toString(10); 4798 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4799 << Value.toString(10); 4800 } 4801 4802 if (!FieldTy->isDependentType()) { 4803 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4804 if (Value.getZExtValue() > TypeSize) { 4805 if (FieldName) 4806 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4807 << FieldName << (unsigned)TypeSize; 4808 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4809 << (unsigned)TypeSize; 4810 } 4811 } 4812 4813 return false; 4814} 4815 4816/// ActOnField - Each field of a struct/union/class is passed into this in order 4817/// to create a FieldDecl object for it. 4818Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4819 SourceLocation DeclStart, 4820 Declarator &D, ExprTy *BitfieldWidth) { 4821 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4822 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4823 AS_public); 4824 return DeclPtrTy::make(Res); 4825} 4826 4827/// HandleField - Analyze a field of a C struct or a C++ data member. 4828/// 4829FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4830 SourceLocation DeclStart, 4831 Declarator &D, Expr *BitWidth, 4832 AccessSpecifier AS) { 4833 IdentifierInfo *II = D.getIdentifier(); 4834 SourceLocation Loc = DeclStart; 4835 if (II) Loc = D.getIdentifierLoc(); 4836 4837 DeclaratorInfo *DInfo = 0; 4838 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4839 if (getLangOptions().CPlusPlus) 4840 CheckExtraCXXDefaultArguments(D); 4841 4842 DiagnoseFunctionSpecifiers(D); 4843 4844 if (D.getDeclSpec().isThreadSpecified()) 4845 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4846 4847 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 4848 LookupResult::ForRedeclaration); 4849 4850 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4851 // Maybe we will complain about the shadowed template parameter. 4852 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4853 // Just pretend that we didn't see the previous declaration. 4854 PrevDecl = 0; 4855 } 4856 4857 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4858 PrevDecl = 0; 4859 4860 bool Mutable 4861 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4862 SourceLocation TSSL = D.getSourceRange().getBegin(); 4863 FieldDecl *NewFD 4864 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4865 AS, PrevDecl, &D); 4866 if (NewFD->isInvalidDecl() && PrevDecl) { 4867 // Don't introduce NewFD into scope; there's already something 4868 // with the same name in the same scope. 4869 } else if (II) { 4870 PushOnScopeChains(NewFD, S); 4871 } else 4872 Record->addDecl(NewFD); 4873 4874 return NewFD; 4875} 4876 4877/// \brief Build a new FieldDecl and check its well-formedness. 4878/// 4879/// This routine builds a new FieldDecl given the fields name, type, 4880/// record, etc. \p PrevDecl should refer to any previous declaration 4881/// with the same name and in the same scope as the field to be 4882/// created. 4883/// 4884/// \returns a new FieldDecl. 4885/// 4886/// \todo The Declarator argument is a hack. It will be removed once 4887FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4888 DeclaratorInfo *DInfo, 4889 RecordDecl *Record, SourceLocation Loc, 4890 bool Mutable, Expr *BitWidth, 4891 SourceLocation TSSL, 4892 AccessSpecifier AS, NamedDecl *PrevDecl, 4893 Declarator *D) { 4894 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4895 bool InvalidDecl = false; 4896 if (D) InvalidDecl = D->isInvalidType(); 4897 4898 // If we receive a broken type, recover by assuming 'int' and 4899 // marking this declaration as invalid. 4900 if (T.isNull()) { 4901 InvalidDecl = true; 4902 T = Context.IntTy; 4903 } 4904 4905 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4906 // than a variably modified type. 4907 if (T->isVariablyModifiedType()) { 4908 bool SizeIsNegative; 4909 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4910 SizeIsNegative); 4911 if (!FixedTy.isNull()) { 4912 Diag(Loc, diag::warn_illegal_constant_array_size); 4913 T = FixedTy; 4914 } else { 4915 if (SizeIsNegative) 4916 Diag(Loc, diag::err_typecheck_negative_array_size); 4917 else 4918 Diag(Loc, diag::err_typecheck_field_variable_size); 4919 InvalidDecl = true; 4920 } 4921 } 4922 4923 // Fields can not have abstract class types 4924 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4925 AbstractFieldType)) 4926 InvalidDecl = true; 4927 4928 bool ZeroWidth = false; 4929 // If this is declared as a bit-field, check the bit-field. 4930 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4931 InvalidDecl = true; 4932 DeleteExpr(BitWidth); 4933 BitWidth = 0; 4934 ZeroWidth = false; 4935 } 4936 4937 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4938 BitWidth, Mutable); 4939 if (InvalidDecl) 4940 NewFD->setInvalidDecl(); 4941 4942 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4943 Diag(Loc, diag::err_duplicate_member) << II; 4944 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4945 NewFD->setInvalidDecl(); 4946 } 4947 4948 if (getLangOptions().CPlusPlus) { 4949 QualType EltTy = Context.getBaseElementType(T); 4950 4951 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4952 4953 if (!T->isPODType()) 4954 CXXRecord->setPOD(false); 4955 if (!ZeroWidth) 4956 CXXRecord->setEmpty(false); 4957 4958 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4959 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4960 4961 if (!RDecl->hasTrivialConstructor()) 4962 CXXRecord->setHasTrivialConstructor(false); 4963 if (!RDecl->hasTrivialCopyConstructor()) 4964 CXXRecord->setHasTrivialCopyConstructor(false); 4965 if (!RDecl->hasTrivialCopyAssignment()) 4966 CXXRecord->setHasTrivialCopyAssignment(false); 4967 if (!RDecl->hasTrivialDestructor()) 4968 CXXRecord->setHasTrivialDestructor(false); 4969 4970 // C++ 9.5p1: An object of a class with a non-trivial 4971 // constructor, a non-trivial copy constructor, a non-trivial 4972 // destructor, or a non-trivial copy assignment operator 4973 // cannot be a member of a union, nor can an array of such 4974 // objects. 4975 // TODO: C++0x alters this restriction significantly. 4976 if (Record->isUnion()) { 4977 // We check for copy constructors before constructors 4978 // because otherwise we'll never get complaints about 4979 // copy constructors. 4980 4981 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4982 4983 CXXSpecialMember member; 4984 if (!RDecl->hasTrivialCopyConstructor()) 4985 member = CXXCopyConstructor; 4986 else if (!RDecl->hasTrivialConstructor()) 4987 member = CXXDefaultConstructor; 4988 else if (!RDecl->hasTrivialCopyAssignment()) 4989 member = CXXCopyAssignment; 4990 else if (!RDecl->hasTrivialDestructor()) 4991 member = CXXDestructor; 4992 else 4993 member = invalid; 4994 4995 if (member != invalid) { 4996 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4997 DiagnoseNontrivial(RT, member); 4998 NewFD->setInvalidDecl(); 4999 } 5000 } 5001 } 5002 } 5003 5004 // FIXME: We need to pass in the attributes given an AST 5005 // representation, not a parser representation. 5006 if (D) 5007 // FIXME: What to pass instead of TUScope? 5008 ProcessDeclAttributes(TUScope, NewFD, *D); 5009 5010 if (T.isObjCGCWeak()) 5011 Diag(Loc, diag::warn_attribute_weak_on_field); 5012 5013 NewFD->setAccess(AS); 5014 5015 // C++ [dcl.init.aggr]p1: 5016 // An aggregate is an array or a class (clause 9) with [...] no 5017 // private or protected non-static data members (clause 11). 5018 // A POD must be an aggregate. 5019 if (getLangOptions().CPlusPlus && 5020 (AS == AS_private || AS == AS_protected)) { 5021 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5022 CXXRecord->setAggregate(false); 5023 CXXRecord->setPOD(false); 5024 } 5025 5026 return NewFD; 5027} 5028 5029/// DiagnoseNontrivial - Given that a class has a non-trivial 5030/// special member, figure out why. 5031void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5032 QualType QT(T, 0U); 5033 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5034 5035 // Check whether the member was user-declared. 5036 switch (member) { 5037 case CXXDefaultConstructor: 5038 if (RD->hasUserDeclaredConstructor()) { 5039 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5040 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5041 const FunctionDecl *body = 0; 5042 ci->getBody(body); 5043 if (!body || 5044 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5045 SourceLocation CtorLoc = ci->getLocation(); 5046 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5047 return; 5048 } 5049 } 5050 5051 assert(0 && "found no user-declared constructors"); 5052 return; 5053 } 5054 break; 5055 5056 case CXXCopyConstructor: 5057 if (RD->hasUserDeclaredCopyConstructor()) { 5058 SourceLocation CtorLoc = 5059 RD->getCopyConstructor(Context, 0)->getLocation(); 5060 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5061 return; 5062 } 5063 break; 5064 5065 case CXXCopyAssignment: 5066 if (RD->hasUserDeclaredCopyAssignment()) { 5067 // FIXME: this should use the location of the copy 5068 // assignment, not the type. 5069 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5070 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5071 return; 5072 } 5073 break; 5074 5075 case CXXDestructor: 5076 if (RD->hasUserDeclaredDestructor()) { 5077 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5078 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5079 return; 5080 } 5081 break; 5082 } 5083 5084 typedef CXXRecordDecl::base_class_iterator base_iter; 5085 5086 // Virtual bases and members inhibit trivial copying/construction, 5087 // but not trivial destruction. 5088 if (member != CXXDestructor) { 5089 // Check for virtual bases. vbases includes indirect virtual bases, 5090 // so we just iterate through the direct bases. 5091 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5092 if (bi->isVirtual()) { 5093 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5094 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5095 return; 5096 } 5097 5098 // Check for virtual methods. 5099 typedef CXXRecordDecl::method_iterator meth_iter; 5100 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5101 ++mi) { 5102 if (mi->isVirtual()) { 5103 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5104 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5105 return; 5106 } 5107 } 5108 } 5109 5110 bool (CXXRecordDecl::*hasTrivial)() const; 5111 switch (member) { 5112 case CXXDefaultConstructor: 5113 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5114 case CXXCopyConstructor: 5115 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5116 case CXXCopyAssignment: 5117 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5118 case CXXDestructor: 5119 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5120 default: 5121 assert(0 && "unexpected special member"); return; 5122 } 5123 5124 // Check for nontrivial bases (and recurse). 5125 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5126 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5127 assert(BaseRT && "Don't know how to handle dependent bases"); 5128 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5129 if (!(BaseRecTy->*hasTrivial)()) { 5130 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5131 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5132 DiagnoseNontrivial(BaseRT, member); 5133 return; 5134 } 5135 } 5136 5137 // Check for nontrivial members (and recurse). 5138 typedef RecordDecl::field_iterator field_iter; 5139 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5140 ++fi) { 5141 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5142 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5143 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5144 5145 if (!(EltRD->*hasTrivial)()) { 5146 SourceLocation FLoc = (*fi)->getLocation(); 5147 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5148 DiagnoseNontrivial(EltRT, member); 5149 return; 5150 } 5151 } 5152 } 5153 5154 assert(0 && "found no explanation for non-trivial member"); 5155} 5156 5157/// TranslateIvarVisibility - Translate visibility from a token ID to an 5158/// AST enum value. 5159static ObjCIvarDecl::AccessControl 5160TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5161 switch (ivarVisibility) { 5162 default: assert(0 && "Unknown visitibility kind"); 5163 case tok::objc_private: return ObjCIvarDecl::Private; 5164 case tok::objc_public: return ObjCIvarDecl::Public; 5165 case tok::objc_protected: return ObjCIvarDecl::Protected; 5166 case tok::objc_package: return ObjCIvarDecl::Package; 5167 } 5168} 5169 5170/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5171/// in order to create an IvarDecl object for it. 5172Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5173 SourceLocation DeclStart, 5174 DeclPtrTy IntfDecl, 5175 Declarator &D, ExprTy *BitfieldWidth, 5176 tok::ObjCKeywordKind Visibility) { 5177 5178 IdentifierInfo *II = D.getIdentifier(); 5179 Expr *BitWidth = (Expr*)BitfieldWidth; 5180 SourceLocation Loc = DeclStart; 5181 if (II) Loc = D.getIdentifierLoc(); 5182 5183 // FIXME: Unnamed fields can be handled in various different ways, for 5184 // example, unnamed unions inject all members into the struct namespace! 5185 5186 DeclaratorInfo *DInfo = 0; 5187 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5188 5189 if (BitWidth) { 5190 // 6.7.2.1p3, 6.7.2.1p4 5191 if (VerifyBitField(Loc, II, T, BitWidth)) { 5192 D.setInvalidType(); 5193 DeleteExpr(BitWidth); 5194 BitWidth = 0; 5195 } 5196 } else { 5197 // Not a bitfield. 5198 5199 // validate II. 5200 5201 } 5202 5203 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5204 // than a variably modified type. 5205 if (T->isVariablyModifiedType()) { 5206 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5207 D.setInvalidType(); 5208 } 5209 5210 // Get the visibility (access control) for this ivar. 5211 ObjCIvarDecl::AccessControl ac = 5212 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5213 : ObjCIvarDecl::None; 5214 // Must set ivar's DeclContext to its enclosing interface. 5215 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5216 DeclContext *EnclosingContext; 5217 if (ObjCImplementationDecl *IMPDecl = 5218 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5219 // Case of ivar declared in an implementation. Context is that of its class. 5220 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5221 assert(IDecl && "No class- ActOnIvar"); 5222 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5223 } else 5224 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5225 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5226 5227 // Construct the decl. 5228 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5229 EnclosingContext, Loc, II, T, 5230 DInfo, ac, (Expr *)BitfieldWidth); 5231 5232 if (II) { 5233 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5234 LookupResult::ForRedeclaration); 5235 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5236 && !isa<TagDecl>(PrevDecl)) { 5237 Diag(Loc, diag::err_duplicate_member) << II; 5238 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5239 NewID->setInvalidDecl(); 5240 } 5241 } 5242 5243 // Process attributes attached to the ivar. 5244 ProcessDeclAttributes(S, NewID, D); 5245 5246 if (D.isInvalidType()) 5247 NewID->setInvalidDecl(); 5248 5249 if (II) { 5250 // FIXME: When interfaces are DeclContexts, we'll need to add 5251 // these to the interface. 5252 S->AddDecl(DeclPtrTy::make(NewID)); 5253 IdResolver.AddDecl(NewID); 5254 } 5255 5256 return DeclPtrTy::make(NewID); 5257} 5258 5259void Sema::ActOnFields(Scope* S, 5260 SourceLocation RecLoc, DeclPtrTy RecDecl, 5261 DeclPtrTy *Fields, unsigned NumFields, 5262 SourceLocation LBrac, SourceLocation RBrac, 5263 AttributeList *Attr) { 5264 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5265 assert(EnclosingDecl && "missing record or interface decl"); 5266 5267 // If the decl this is being inserted into is invalid, then it may be a 5268 // redeclaration or some other bogus case. Don't try to add fields to it. 5269 if (EnclosingDecl->isInvalidDecl()) { 5270 // FIXME: Deallocate fields? 5271 return; 5272 } 5273 5274 5275 // Verify that all the fields are okay. 5276 unsigned NumNamedMembers = 0; 5277 llvm::SmallVector<FieldDecl*, 32> RecFields; 5278 5279 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5280 for (unsigned i = 0; i != NumFields; ++i) { 5281 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5282 5283 // Get the type for the field. 5284 Type *FDTy = FD->getType().getTypePtr(); 5285 5286 if (!FD->isAnonymousStructOrUnion()) { 5287 // Remember all fields written by the user. 5288 RecFields.push_back(FD); 5289 } 5290 5291 // If the field is already invalid for some reason, don't emit more 5292 // diagnostics about it. 5293 if (FD->isInvalidDecl()) 5294 continue; 5295 5296 // C99 6.7.2.1p2: 5297 // A structure or union shall not contain a member with 5298 // incomplete or function type (hence, a structure shall not 5299 // contain an instance of itself, but may contain a pointer to 5300 // an instance of itself), except that the last member of a 5301 // structure with more than one named member may have incomplete 5302 // array type; such a structure (and any union containing, 5303 // possibly recursively, a member that is such a structure) 5304 // shall not be a member of a structure or an element of an 5305 // array. 5306 if (FDTy->isFunctionType()) { 5307 // Field declared as a function. 5308 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5309 << FD->getDeclName(); 5310 FD->setInvalidDecl(); 5311 EnclosingDecl->setInvalidDecl(); 5312 continue; 5313 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5314 Record && Record->isStruct()) { 5315 // Flexible array member. 5316 if (NumNamedMembers < 1) { 5317 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5318 << FD->getDeclName(); 5319 FD->setInvalidDecl(); 5320 EnclosingDecl->setInvalidDecl(); 5321 continue; 5322 } 5323 // Okay, we have a legal flexible array member at the end of the struct. 5324 if (Record) 5325 Record->setHasFlexibleArrayMember(true); 5326 } else if (!FDTy->isDependentType() && 5327 RequireCompleteType(FD->getLocation(), FD->getType(), 5328 diag::err_field_incomplete)) { 5329 // Incomplete type 5330 FD->setInvalidDecl(); 5331 EnclosingDecl->setInvalidDecl(); 5332 continue; 5333 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5334 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5335 // If this is a member of a union, then entire union becomes "flexible". 5336 if (Record && Record->isUnion()) { 5337 Record->setHasFlexibleArrayMember(true); 5338 } else { 5339 // If this is a struct/class and this is not the last element, reject 5340 // it. Note that GCC supports variable sized arrays in the middle of 5341 // structures. 5342 if (i != NumFields-1) 5343 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5344 << FD->getDeclName() << FD->getType(); 5345 else { 5346 // We support flexible arrays at the end of structs in 5347 // other structs as an extension. 5348 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5349 << FD->getDeclName(); 5350 if (Record) 5351 Record->setHasFlexibleArrayMember(true); 5352 } 5353 } 5354 } 5355 if (Record && FDTTy->getDecl()->hasObjectMember()) 5356 Record->setHasObjectMember(true); 5357 } else if (FDTy->isObjCInterfaceType()) { 5358 /// A field cannot be an Objective-c object 5359 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5360 FD->setInvalidDecl(); 5361 EnclosingDecl->setInvalidDecl(); 5362 continue; 5363 } else if (getLangOptions().ObjC1 && 5364 getLangOptions().getGCMode() != LangOptions::NonGC && 5365 Record && 5366 (FD->getType()->isObjCObjectPointerType() || 5367 FD->getType().isObjCGCStrong())) 5368 Record->setHasObjectMember(true); 5369 // Keep track of the number of named members. 5370 if (FD->getIdentifier()) 5371 ++NumNamedMembers; 5372 } 5373 5374 // Okay, we successfully defined 'Record'. 5375 if (Record) { 5376 Record->completeDefinition(Context); 5377 } else { 5378 ObjCIvarDecl **ClsFields = 5379 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5380 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5381 ID->setIVarList(ClsFields, RecFields.size(), Context); 5382 ID->setLocEnd(RBrac); 5383 // Add ivar's to class's DeclContext. 5384 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5385 ClsFields[i]->setLexicalDeclContext(ID); 5386 ID->addDecl(ClsFields[i]); 5387 } 5388 // Must enforce the rule that ivars in the base classes may not be 5389 // duplicates. 5390 if (ID->getSuperClass()) { 5391 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5392 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5393 ObjCIvarDecl* Ivar = (*IVI); 5394 5395 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5396 ObjCIvarDecl* prevIvar = 5397 ID->getSuperClass()->lookupInstanceVariable(II); 5398 if (prevIvar) { 5399 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5400 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5401 } 5402 } 5403 } 5404 } 5405 } else if (ObjCImplementationDecl *IMPDecl = 5406 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5407 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5408 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5409 // Ivar declared in @implementation never belongs to the implementation. 5410 // Only it is in implementation's lexical context. 5411 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5412 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5413 } 5414 } 5415 5416 if (Attr) 5417 ProcessDeclAttributeList(S, Record, Attr); 5418} 5419 5420EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5421 EnumConstantDecl *LastEnumConst, 5422 SourceLocation IdLoc, 5423 IdentifierInfo *Id, 5424 ExprArg val) { 5425 Expr *Val = (Expr *)val.get(); 5426 5427 llvm::APSInt EnumVal(32); 5428 QualType EltTy; 5429 if (Val) { 5430 if (Val->isTypeDependent()) 5431 EltTy = Context.DependentTy; 5432 else { 5433 // Make sure to promote the operand type to int. 5434 UsualUnaryConversions(Val); 5435 if (Val != val.get()) { 5436 val.release(); 5437 val = Val; 5438 } 5439 5440 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5441 SourceLocation ExpLoc; 5442 if (!Val->isValueDependent() && 5443 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5444 Val = 0; 5445 } else { 5446 EltTy = Val->getType(); 5447 } 5448 } 5449 } 5450 5451 if (!Val) { 5452 if (LastEnumConst) { 5453 // Assign the last value + 1. 5454 EnumVal = LastEnumConst->getInitVal(); 5455 ++EnumVal; 5456 5457 // Check for overflow on increment. 5458 if (EnumVal < LastEnumConst->getInitVal()) 5459 Diag(IdLoc, diag::warn_enum_value_overflow); 5460 5461 EltTy = LastEnumConst->getType(); 5462 } else { 5463 // First value, set to zero. 5464 EltTy = Context.IntTy; 5465 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5466 } 5467 } 5468 5469 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5470 5471 val.release(); 5472 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5473 Val, EnumVal); 5474} 5475 5476 5477Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5478 DeclPtrTy lastEnumConst, 5479 SourceLocation IdLoc, 5480 IdentifierInfo *Id, 5481 SourceLocation EqualLoc, ExprTy *val) { 5482 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5483 EnumConstantDecl *LastEnumConst = 5484 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5485 Expr *Val = static_cast<Expr*>(val); 5486 5487 // The scope passed in may not be a decl scope. Zip up the scope tree until 5488 // we find one that is. 5489 S = getNonFieldDeclScope(S); 5490 5491 // Verify that there isn't already something declared with this name in this 5492 // scope. 5493 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5494 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5495 // Maybe we will complain about the shadowed template parameter. 5496 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5497 // Just pretend that we didn't see the previous declaration. 5498 PrevDecl = 0; 5499 } 5500 5501 if (PrevDecl) { 5502 // When in C++, we may get a TagDecl with the same name; in this case the 5503 // enum constant will 'hide' the tag. 5504 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5505 "Received TagDecl when not in C++!"); 5506 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5507 if (isa<EnumConstantDecl>(PrevDecl)) 5508 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5509 else 5510 Diag(IdLoc, diag::err_redefinition) << Id; 5511 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5512 if (Val) Val->Destroy(Context); 5513 return DeclPtrTy(); 5514 } 5515 } 5516 5517 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5518 IdLoc, Id, Owned(Val)); 5519 5520 // Register this decl in the current scope stack. 5521 if (New) 5522 PushOnScopeChains(New, S); 5523 5524 return DeclPtrTy::make(New); 5525} 5526 5527void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5528 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5529 DeclPtrTy *Elements, unsigned NumElements, 5530 Scope *S, AttributeList *Attr) { 5531 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5532 QualType EnumType = Context.getTypeDeclType(Enum); 5533 5534 if (Attr) 5535 ProcessDeclAttributeList(S, Enum, Attr); 5536 5537 // TODO: If the result value doesn't fit in an int, it must be a long or long 5538 // long value. ISO C does not support this, but GCC does as an extension, 5539 // emit a warning. 5540 unsigned IntWidth = Context.Target.getIntWidth(); 5541 unsigned CharWidth = Context.Target.getCharWidth(); 5542 unsigned ShortWidth = Context.Target.getShortWidth(); 5543 5544 // Verify that all the values are okay, compute the size of the values, and 5545 // reverse the list. 5546 unsigned NumNegativeBits = 0; 5547 unsigned NumPositiveBits = 0; 5548 5549 // Keep track of whether all elements have type int. 5550 bool AllElementsInt = true; 5551 5552 for (unsigned i = 0; i != NumElements; ++i) { 5553 EnumConstantDecl *ECD = 5554 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5555 if (!ECD) continue; // Already issued a diagnostic. 5556 5557 // If the enum value doesn't fit in an int, emit an extension warning. 5558 const llvm::APSInt &InitVal = ECD->getInitVal(); 5559 assert(InitVal.getBitWidth() >= IntWidth && 5560 "Should have promoted value to int"); 5561 if (InitVal.getBitWidth() > IntWidth) { 5562 llvm::APSInt V(InitVal); 5563 V.trunc(IntWidth); 5564 V.extend(InitVal.getBitWidth()); 5565 if (V != InitVal) 5566 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5567 << InitVal.toString(10); 5568 } 5569 5570 // Keep track of the size of positive and negative values. 5571 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5572 NumPositiveBits = std::max(NumPositiveBits, 5573 (unsigned)InitVal.getActiveBits()); 5574 else 5575 NumNegativeBits = std::max(NumNegativeBits, 5576 (unsigned)InitVal.getMinSignedBits()); 5577 5578 // Keep track of whether every enum element has type int (very commmon). 5579 if (AllElementsInt) 5580 AllElementsInt = ECD->getType() == Context.IntTy; 5581 } 5582 5583 // Figure out the type that should be used for this enum. 5584 // FIXME: Support -fshort-enums. 5585 QualType BestType; 5586 unsigned BestWidth; 5587 5588 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5589 5590 if (NumNegativeBits) { 5591 // If there is a negative value, figure out the smallest integer type (of 5592 // int/long/longlong) that fits. 5593 // If it's packed, check also if it fits a char or a short. 5594 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5595 BestType = Context.SignedCharTy; 5596 BestWidth = CharWidth; 5597 } else if (Packed && NumNegativeBits <= ShortWidth && 5598 NumPositiveBits < ShortWidth) { 5599 BestType = Context.ShortTy; 5600 BestWidth = ShortWidth; 5601 } 5602 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5603 BestType = Context.IntTy; 5604 BestWidth = IntWidth; 5605 } else { 5606 BestWidth = Context.Target.getLongWidth(); 5607 5608 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5609 BestType = Context.LongTy; 5610 else { 5611 BestWidth = Context.Target.getLongLongWidth(); 5612 5613 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5614 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5615 BestType = Context.LongLongTy; 5616 } 5617 } 5618 } else { 5619 // If there is no negative value, figure out which of uint, ulong, ulonglong 5620 // fits. 5621 // If it's packed, check also if it fits a char or a short. 5622 if (Packed && NumPositiveBits <= CharWidth) { 5623 BestType = Context.UnsignedCharTy; 5624 BestWidth = CharWidth; 5625 } else if (Packed && NumPositiveBits <= ShortWidth) { 5626 BestType = Context.UnsignedShortTy; 5627 BestWidth = ShortWidth; 5628 } 5629 else if (NumPositiveBits <= IntWidth) { 5630 BestType = Context.UnsignedIntTy; 5631 BestWidth = IntWidth; 5632 } else if (NumPositiveBits <= 5633 (BestWidth = Context.Target.getLongWidth())) { 5634 BestType = Context.UnsignedLongTy; 5635 } else { 5636 BestWidth = Context.Target.getLongLongWidth(); 5637 assert(NumPositiveBits <= BestWidth && 5638 "How could an initializer get larger than ULL?"); 5639 BestType = Context.UnsignedLongLongTy; 5640 } 5641 } 5642 5643 // Loop over all of the enumerator constants, changing their types to match 5644 // the type of the enum if needed. 5645 for (unsigned i = 0; i != NumElements; ++i) { 5646 EnumConstantDecl *ECD = 5647 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5648 if (!ECD) continue; // Already issued a diagnostic. 5649 5650 // Standard C says the enumerators have int type, but we allow, as an 5651 // extension, the enumerators to be larger than int size. If each 5652 // enumerator value fits in an int, type it as an int, otherwise type it the 5653 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5654 // that X has type 'int', not 'unsigned'. 5655 if (ECD->getType() == Context.IntTy) { 5656 // Make sure the init value is signed. 5657 llvm::APSInt IV = ECD->getInitVal(); 5658 IV.setIsSigned(true); 5659 ECD->setInitVal(IV); 5660 5661 if (getLangOptions().CPlusPlus) 5662 // C++ [dcl.enum]p4: Following the closing brace of an 5663 // enum-specifier, each enumerator has the type of its 5664 // enumeration. 5665 ECD->setType(EnumType); 5666 continue; // Already int type. 5667 } 5668 5669 // Determine whether the value fits into an int. 5670 llvm::APSInt InitVal = ECD->getInitVal(); 5671 bool FitsInInt; 5672 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5673 FitsInInt = InitVal.getActiveBits() < IntWidth; 5674 else 5675 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5676 5677 // If it fits into an integer type, force it. Otherwise force it to match 5678 // the enum decl type. 5679 QualType NewTy; 5680 unsigned NewWidth; 5681 bool NewSign; 5682 if (FitsInInt) { 5683 NewTy = Context.IntTy; 5684 NewWidth = IntWidth; 5685 NewSign = true; 5686 } else if (ECD->getType() == BestType) { 5687 // Already the right type! 5688 if (getLangOptions().CPlusPlus) 5689 // C++ [dcl.enum]p4: Following the closing brace of an 5690 // enum-specifier, each enumerator has the type of its 5691 // enumeration. 5692 ECD->setType(EnumType); 5693 continue; 5694 } else { 5695 NewTy = BestType; 5696 NewWidth = BestWidth; 5697 NewSign = BestType->isSignedIntegerType(); 5698 } 5699 5700 // Adjust the APSInt value. 5701 InitVal.extOrTrunc(NewWidth); 5702 InitVal.setIsSigned(NewSign); 5703 ECD->setInitVal(InitVal); 5704 5705 // Adjust the Expr initializer and type. 5706 if (ECD->getInitExpr()) 5707 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5708 CastExpr::CK_IntegralCast, 5709 ECD->getInitExpr(), 5710 /*isLvalue=*/false)); 5711 if (getLangOptions().CPlusPlus) 5712 // C++ [dcl.enum]p4: Following the closing brace of an 5713 // enum-specifier, each enumerator has the type of its 5714 // enumeration. 5715 ECD->setType(EnumType); 5716 else 5717 ECD->setType(NewTy); 5718 } 5719 5720 Enum->completeDefinition(Context, BestType); 5721} 5722 5723Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5724 ExprArg expr) { 5725 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5726 5727 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5728 Loc, AsmString); 5729 CurContext->addDecl(New); 5730 return DeclPtrTy::make(New); 5731} 5732 5733void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5734 SourceLocation PragmaLoc, 5735 SourceLocation NameLoc) { 5736 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5737 5738 if (PrevDecl) { 5739 PrevDecl->addAttr(::new (Context) WeakAttr()); 5740 } else { 5741 (void)WeakUndeclaredIdentifiers.insert( 5742 std::pair<IdentifierInfo*,WeakInfo> 5743 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5744 } 5745} 5746 5747void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5748 IdentifierInfo* AliasName, 5749 SourceLocation PragmaLoc, 5750 SourceLocation NameLoc, 5751 SourceLocation AliasNameLoc) { 5752 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5753 WeakInfo W = WeakInfo(Name, NameLoc); 5754 5755 if (PrevDecl) { 5756 if (!PrevDecl->hasAttr<AliasAttr>()) 5757 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5758 DeclApplyPragmaWeak(TUScope, ND, W); 5759 } else { 5760 (void)WeakUndeclaredIdentifiers.insert( 5761 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5762 } 5763} 5764