SemaDecl.cpp revision b226b2e8514db1c679ed27ebd6a241e0f4cacac6
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/Analysis/CFG.h" 19#include "clang/AST/CXXInheritance.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Parse/ParseDiagnostic.h" 27#include "clang/Parse/Template.h" 28#include "clang/Basic/PartialDiagnostic.h" 29#include "clang/Basic/SourceManager.h" 30#include "clang/Basic/TargetInfo.h" 31// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 32#include "clang/Lex/Preprocessor.h" 33#include "clang/Lex/HeaderSearch.h" 34#include "llvm/ADT/BitVector.h" 35#include "llvm/ADT/STLExtras.h" 36#include <algorithm> 37#include <cstring> 38#include <functional> 39#include <queue> 40using namespace clang; 41 42/// getDeclName - Return a pretty name for the specified decl if possible, or 43/// an empty string if not. This is used for pretty crash reporting. 44std::string Sema::getDeclName(DeclPtrTy d) { 45 Decl *D = d.getAs<Decl>(); 46 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 47 return DN->getQualifiedNameAsString(); 48 return ""; 49} 50 51Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 52 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 53} 54 55/// \brief If the identifier refers to a type name within this scope, 56/// return the declaration of that type. 57/// 58/// This routine performs ordinary name lookup of the identifier II 59/// within the given scope, with optional C++ scope specifier SS, to 60/// determine whether the name refers to a type. If so, returns an 61/// opaque pointer (actually a QualType) corresponding to that 62/// type. Otherwise, returns NULL. 63/// 64/// If name lookup results in an ambiguity, this routine will complain 65/// and then return NULL. 66Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 67 Scope *S, const CXXScopeSpec *SS, 68 bool isClassName) { 69 // C++ [temp.res]p3: 70 // A qualified-id that refers to a type and in which the 71 // nested-name-specifier depends on a template-parameter (14.6.2) 72 // shall be prefixed by the keyword typename to indicate that the 73 // qualified-id denotes a type, forming an 74 // elaborated-type-specifier (7.1.5.3). 75 // 76 // We therefore do not perform any name lookup if the result would 77 // refer to a member of an unknown specialization. 78 if (SS && isUnknownSpecialization(*SS)) { 79 if (!isClassName) 80 return 0; 81 82 // We know from the grammar that this name refers to a type, so build a 83 // TypenameType node to describe the type. 84 // FIXME: Record somewhere that this TypenameType node has no "typename" 85 // keyword associated with it. 86 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 87 II, SS->getRange()).getAsOpaquePtr(); 88 } 89 90 LookupResult Result; 91 LookupParsedName(Result, S, SS, &II, LookupOrdinaryName, false, false); 92 93 NamedDecl *IIDecl = 0; 94 switch (Result.getKind()) { 95 case LookupResult::NotFound: 96 case LookupResult::FoundOverloaded: 97 return 0; 98 99 case LookupResult::Ambiguous: 100 // Recover from type-hiding ambiguities by hiding the type. We'll 101 // do the lookup again when looking for an object, and we can 102 // diagnose the error then. If we don't do this, then the error 103 // about hiding the type will be immediately followed by an error 104 // that only makes sense if the identifier was treated like a type. 105 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) 106 return 0; 107 108 // Look to see if we have a type anywhere in the list of results. 109 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 110 Res != ResEnd; ++Res) { 111 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 112 if (!IIDecl || 113 (*Res)->getLocation().getRawEncoding() < 114 IIDecl->getLocation().getRawEncoding()) 115 IIDecl = *Res; 116 } 117 } 118 119 if (!IIDecl) { 120 // None of the entities we found is a type, so there is no way 121 // to even assume that the result is a type. In this case, don't 122 // complain about the ambiguity. The parser will either try to 123 // perform this lookup again (e.g., as an object name), which 124 // will produce the ambiguity, or will complain that it expected 125 // a type name. 126 return 0; 127 } 128 129 // We found a type within the ambiguous lookup; diagnose the 130 // ambiguity and then return that type. This might be the right 131 // answer, or it might not be, but it suppresses any attempt to 132 // perform the name lookup again. 133 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 134 break; 135 136 case LookupResult::Found: 137 IIDecl = Result.getFoundDecl(); 138 break; 139 } 140 141 assert(IIDecl && "Didn't find decl"); 142 143 QualType T; 144 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 145 DiagnoseUseOfDecl(IIDecl, NameLoc); 146 147 // C++ [temp.local]p2: 148 // Within the scope of a class template specialization or 149 // partial specialization, when the injected-class-name is 150 // not followed by a <, it is equivalent to the 151 // injected-class-name followed by the template-argument s 152 // of the class template specialization or partial 153 // specialization enclosed in <>. 154 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 155 if (RD->isInjectedClassName()) 156 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 157 T = Template->getInjectedClassNameType(Context); 158 159 if (T.isNull()) 160 T = Context.getTypeDeclType(TD); 161 162 if (SS) 163 T = getQualifiedNameType(*SS, T); 164 165 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 166 DiagnoseUseOfDecl(IIDecl, NameLoc); 167 T = Context.getObjCInterfaceType(IDecl); 168 } else 169 return 0; 170 171 return T.getAsOpaquePtr(); 172} 173 174/// isTagName() - This method is called *for error recovery purposes only* 175/// to determine if the specified name is a valid tag name ("struct foo"). If 176/// so, this returns the TST for the tag corresponding to it (TST_enum, 177/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 178/// where the user forgot to specify the tag. 179DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 180 // Do a tag name lookup in this scope. 181 LookupResult R; 182 LookupName(R, S, &II, LookupTagName, false, false); 183 if (R.getKind() == LookupResult::Found) 184 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 185 switch (TD->getTagKind()) { 186 case TagDecl::TK_struct: return DeclSpec::TST_struct; 187 case TagDecl::TK_union: return DeclSpec::TST_union; 188 case TagDecl::TK_class: return DeclSpec::TST_class; 189 case TagDecl::TK_enum: return DeclSpec::TST_enum; 190 } 191 } 192 193 return DeclSpec::TST_unspecified; 194} 195 196bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 197 SourceLocation IILoc, 198 Scope *S, 199 const CXXScopeSpec *SS, 200 TypeTy *&SuggestedType) { 201 // We don't have anything to suggest (yet). 202 SuggestedType = 0; 203 204 // FIXME: Should we move the logic that tries to recover from a missing tag 205 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 206 207 if (!SS) 208 Diag(IILoc, diag::err_unknown_typename) << &II; 209 else if (DeclContext *DC = computeDeclContext(*SS, false)) 210 Diag(IILoc, diag::err_typename_nested_not_found) 211 << &II << DC << SS->getRange(); 212 else if (isDependentScopeSpecifier(*SS)) { 213 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 214 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 215 << SourceRange(SS->getRange().getBegin(), IILoc) 216 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 217 "typename "); 218 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 219 } else { 220 assert(SS && SS->isInvalid() && 221 "Invalid scope specifier has already been diagnosed"); 222 } 223 224 return true; 225} 226 227// Determines the context to return to after temporarily entering a 228// context. This depends in an unnecessarily complicated way on the 229// exact ordering of callbacks from the parser. 230DeclContext *Sema::getContainingDC(DeclContext *DC) { 231 232 // Functions defined inline within classes aren't parsed until we've 233 // finished parsing the top-level class, so the top-level class is 234 // the context we'll need to return to. 235 if (isa<FunctionDecl>(DC)) { 236 DC = DC->getLexicalParent(); 237 238 // A function not defined within a class will always return to its 239 // lexical context. 240 if (!isa<CXXRecordDecl>(DC)) 241 return DC; 242 243 // A C++ inline method/friend is parsed *after* the topmost class 244 // it was declared in is fully parsed ("complete"); the topmost 245 // class is the context we need to return to. 246 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 247 DC = RD; 248 249 // Return the declaration context of the topmost class the inline method is 250 // declared in. 251 return DC; 252 } 253 254 if (isa<ObjCMethodDecl>(DC)) 255 return Context.getTranslationUnitDecl(); 256 257 return DC->getLexicalParent(); 258} 259 260void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 261 assert(getContainingDC(DC) == CurContext && 262 "The next DeclContext should be lexically contained in the current one."); 263 CurContext = DC; 264 S->setEntity(DC); 265} 266 267void Sema::PopDeclContext() { 268 assert(CurContext && "DeclContext imbalance!"); 269 270 CurContext = getContainingDC(CurContext); 271} 272 273/// EnterDeclaratorContext - Used when we must lookup names in the context 274/// of a declarator's nested name specifier. 275void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 276 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 277 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 278 CurContext = DC; 279 assert(CurContext && "No context?"); 280 S->setEntity(CurContext); 281} 282 283void Sema::ExitDeclaratorContext(Scope *S) { 284 S->setEntity(PreDeclaratorDC); 285 PreDeclaratorDC = 0; 286 287 // Reset CurContext to the nearest enclosing context. 288 while (!S->getEntity() && S->getParent()) 289 S = S->getParent(); 290 CurContext = static_cast<DeclContext*>(S->getEntity()); 291 assert(CurContext && "No context?"); 292} 293 294/// \brief Determine whether we allow overloading of the function 295/// PrevDecl with another declaration. 296/// 297/// This routine determines whether overloading is possible, not 298/// whether some new function is actually an overload. It will return 299/// true in C++ (where we can always provide overloads) or, as an 300/// extension, in C when the previous function is already an 301/// overloaded function declaration or has the "overloadable" 302/// attribute. 303static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 304 if (Context.getLangOptions().CPlusPlus) 305 return true; 306 307 if (isa<OverloadedFunctionDecl>(PrevDecl)) 308 return true; 309 310 return PrevDecl->getAttr<OverloadableAttr>() != 0; 311} 312 313/// Add this decl to the scope shadowed decl chains. 314void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 315 // Move up the scope chain until we find the nearest enclosing 316 // non-transparent context. The declaration will be introduced into this 317 // scope. 318 while (S->getEntity() && 319 ((DeclContext *)S->getEntity())->isTransparentContext()) 320 S = S->getParent(); 321 322 // Add scoped declarations into their context, so that they can be 323 // found later. Declarations without a context won't be inserted 324 // into any context. 325 if (AddToContext) 326 CurContext->addDecl(D); 327 328 // Out-of-line function and variable definitions should not be pushed into 329 // scope. 330 if ((isa<FunctionTemplateDecl>(D) && 331 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 332 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 333 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 334 return; 335 336 // If this replaces anything in the current scope, 337 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 338 IEnd = IdResolver.end(); 339 for (; I != IEnd; ++I) { 340 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 341 S->RemoveDecl(DeclPtrTy::make(*I)); 342 IdResolver.RemoveDecl(*I); 343 344 // Should only need to replace one decl. 345 break; 346 } 347 } 348 349 S->AddDecl(DeclPtrTy::make(D)); 350 IdResolver.AddDecl(D); 351} 352 353bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 354 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 355 // Look inside the overload set to determine if any of the declarations 356 // are in scope. (Possibly) build a new overload set containing only 357 // those declarations that are in scope. 358 OverloadedFunctionDecl *NewOvl = 0; 359 bool FoundInScope = false; 360 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 361 FEnd = Ovl->function_end(); 362 F != FEnd; ++F) { 363 NamedDecl *FD = F->get(); 364 if (!isDeclInScope(FD, Ctx, S)) { 365 if (!NewOvl && F != Ovl->function_begin()) { 366 NewOvl = OverloadedFunctionDecl::Create(Context, 367 F->get()->getDeclContext(), 368 F->get()->getDeclName()); 369 D = NewOvl; 370 for (OverloadedFunctionDecl::function_iterator 371 First = Ovl->function_begin(); 372 First != F; ++First) 373 NewOvl->addOverload(*First); 374 } 375 } else { 376 FoundInScope = true; 377 if (NewOvl) 378 NewOvl->addOverload(*F); 379 } 380 } 381 382 return FoundInScope; 383 } 384 385 return IdResolver.isDeclInScope(D, Ctx, Context, S); 386} 387 388static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 389 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 390 return false; 391 392 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 393 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 394 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 395 if (!RD->hasTrivialConstructor()) 396 return false; 397 if (!RD->hasTrivialDestructor()) 398 return false; 399 } 400 } 401 } 402 403 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 404 !isa<ImplicitParamDecl>(D) && 405 D->getDeclContext()->isFunctionOrMethod()); 406} 407 408void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 409 if (S->decl_empty()) return; 410 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 411 "Scope shouldn't contain decls!"); 412 413 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 414 I != E; ++I) { 415 Decl *TmpD = (*I).getAs<Decl>(); 416 assert(TmpD && "This decl didn't get pushed??"); 417 418 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 419 NamedDecl *D = cast<NamedDecl>(TmpD); 420 421 if (!D->getDeclName()) continue; 422 423 // Diagnose unused variables in this scope. 424 if (ShouldDiagnoseUnusedDecl(D)) 425 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 426 427 // Remove this name from our lexical scope. 428 IdResolver.RemoveDecl(D); 429 } 430} 431 432/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 433/// return 0 if one not found. 434ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 435 // The third "scope" argument is 0 since we aren't enabling lazy built-in 436 // creation from this context. 437 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 438 439 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 440} 441 442/// getNonFieldDeclScope - Retrieves the innermost scope, starting 443/// from S, where a non-field would be declared. This routine copes 444/// with the difference between C and C++ scoping rules in structs and 445/// unions. For example, the following code is well-formed in C but 446/// ill-formed in C++: 447/// @code 448/// struct S6 { 449/// enum { BAR } e; 450/// }; 451/// 452/// void test_S6() { 453/// struct S6 a; 454/// a.e = BAR; 455/// } 456/// @endcode 457/// For the declaration of BAR, this routine will return a different 458/// scope. The scope S will be the scope of the unnamed enumeration 459/// within S6. In C++, this routine will return the scope associated 460/// with S6, because the enumeration's scope is a transparent 461/// context but structures can contain non-field names. In C, this 462/// routine will return the translation unit scope, since the 463/// enumeration's scope is a transparent context and structures cannot 464/// contain non-field names. 465Scope *Sema::getNonFieldDeclScope(Scope *S) { 466 while (((S->getFlags() & Scope::DeclScope) == 0) || 467 (S->getEntity() && 468 ((DeclContext *)S->getEntity())->isTransparentContext()) || 469 (S->isClassScope() && !getLangOptions().CPlusPlus)) 470 S = S->getParent(); 471 return S; 472} 473 474void Sema::InitBuiltinVaListType() { 475 if (!Context.getBuiltinVaListType().isNull()) 476 return; 477 478 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 479 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 480 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 481 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 482} 483 484/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 485/// file scope. lazily create a decl for it. ForRedeclaration is true 486/// if we're creating this built-in in anticipation of redeclaring the 487/// built-in. 488NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 489 Scope *S, bool ForRedeclaration, 490 SourceLocation Loc) { 491 Builtin::ID BID = (Builtin::ID)bid; 492 493 if (Context.BuiltinInfo.hasVAListUse(BID)) 494 InitBuiltinVaListType(); 495 496 ASTContext::GetBuiltinTypeError Error; 497 QualType R = Context.GetBuiltinType(BID, Error); 498 switch (Error) { 499 case ASTContext::GE_None: 500 // Okay 501 break; 502 503 case ASTContext::GE_Missing_stdio: 504 if (ForRedeclaration) 505 Diag(Loc, diag::err_implicit_decl_requires_stdio) 506 << Context.BuiltinInfo.GetName(BID); 507 return 0; 508 509 case ASTContext::GE_Missing_setjmp: 510 if (ForRedeclaration) 511 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 512 << Context.BuiltinInfo.GetName(BID); 513 return 0; 514 } 515 516 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 517 Diag(Loc, diag::ext_implicit_lib_function_decl) 518 << Context.BuiltinInfo.GetName(BID) 519 << R; 520 if (Context.BuiltinInfo.getHeaderName(BID) && 521 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 522 != Diagnostic::Ignored) 523 Diag(Loc, diag::note_please_include_header) 524 << Context.BuiltinInfo.getHeaderName(BID) 525 << Context.BuiltinInfo.GetName(BID); 526 } 527 528 FunctionDecl *New = FunctionDecl::Create(Context, 529 Context.getTranslationUnitDecl(), 530 Loc, II, R, /*DInfo=*/0, 531 FunctionDecl::Extern, false, 532 /*hasPrototype=*/true); 533 New->setImplicit(); 534 535 // Create Decl objects for each parameter, adding them to the 536 // FunctionDecl. 537 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 538 llvm::SmallVector<ParmVarDecl*, 16> Params; 539 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 540 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 541 FT->getArgType(i), /*DInfo=*/0, 542 VarDecl::None, 0)); 543 New->setParams(Context, Params.data(), Params.size()); 544 } 545 546 AddKnownFunctionAttributes(New); 547 548 // TUScope is the translation-unit scope to insert this function into. 549 // FIXME: This is hideous. We need to teach PushOnScopeChains to 550 // relate Scopes to DeclContexts, and probably eliminate CurContext 551 // entirely, but we're not there yet. 552 DeclContext *SavedContext = CurContext; 553 CurContext = Context.getTranslationUnitDecl(); 554 PushOnScopeChains(New, TUScope); 555 CurContext = SavedContext; 556 return New; 557} 558 559/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 560/// same name and scope as a previous declaration 'Old'. Figure out 561/// how to resolve this situation, merging decls or emitting 562/// diagnostics as appropriate. If there was an error, set New to be invalid. 563/// 564void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 565 // If either decl is known invalid already, set the new one to be invalid and 566 // don't bother doing any merging checks. 567 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 568 return New->setInvalidDecl(); 569 570 // Allow multiple definitions for ObjC built-in typedefs. 571 // FIXME: Verify the underlying types are equivalent! 572 if (getLangOptions().ObjC1) { 573 const IdentifierInfo *TypeID = New->getIdentifier(); 574 switch (TypeID->getLength()) { 575 default: break; 576 case 2: 577 if (!TypeID->isStr("id")) 578 break; 579 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 580 // Install the built-in type for 'id', ignoring the current definition. 581 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 582 return; 583 case 5: 584 if (!TypeID->isStr("Class")) 585 break; 586 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 587 // Install the built-in type for 'Class', ignoring the current definition. 588 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 589 return; 590 case 3: 591 if (!TypeID->isStr("SEL")) 592 break; 593 Context.setObjCSelType(Context.getTypeDeclType(New)); 594 return; 595 case 8: 596 if (!TypeID->isStr("Protocol")) 597 break; 598 Context.setObjCProtoType(New->getUnderlyingType()); 599 return; 600 } 601 // Fall through - the typedef name was not a builtin type. 602 } 603 // Verify the old decl was also a type. 604 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 605 if (!Old) { 606 Diag(New->getLocation(), diag::err_redefinition_different_kind) 607 << New->getDeclName(); 608 if (OldD->getLocation().isValid()) 609 Diag(OldD->getLocation(), diag::note_previous_definition); 610 return New->setInvalidDecl(); 611 } 612 613 // Determine the "old" type we'll use for checking and diagnostics. 614 QualType OldType; 615 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 616 OldType = OldTypedef->getUnderlyingType(); 617 else 618 OldType = Context.getTypeDeclType(Old); 619 620 // If the typedef types are not identical, reject them in all languages and 621 // with any extensions enabled. 622 623 if (OldType != New->getUnderlyingType() && 624 Context.getCanonicalType(OldType) != 625 Context.getCanonicalType(New->getUnderlyingType())) { 626 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 627 << New->getUnderlyingType() << OldType; 628 if (Old->getLocation().isValid()) 629 Diag(Old->getLocation(), diag::note_previous_definition); 630 return New->setInvalidDecl(); 631 } 632 633 if (getLangOptions().Microsoft) 634 return; 635 636 // C++ [dcl.typedef]p2: 637 // In a given non-class scope, a typedef specifier can be used to 638 // redefine the name of any type declared in that scope to refer 639 // to the type to which it already refers. 640 if (getLangOptions().CPlusPlus) { 641 if (!isa<CXXRecordDecl>(CurContext)) 642 return; 643 Diag(New->getLocation(), diag::err_redefinition) 644 << New->getDeclName(); 645 Diag(Old->getLocation(), diag::note_previous_definition); 646 return New->setInvalidDecl(); 647 } 648 649 // If we have a redefinition of a typedef in C, emit a warning. This warning 650 // is normally mapped to an error, but can be controlled with 651 // -Wtypedef-redefinition. If either the original or the redefinition is 652 // in a system header, don't emit this for compatibility with GCC. 653 if (PP.getDiagnostics().getSuppressSystemWarnings() && 654 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 655 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 656 return; 657 658 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 659 << New->getDeclName(); 660 Diag(Old->getLocation(), diag::note_previous_definition); 661 return; 662} 663 664/// DeclhasAttr - returns true if decl Declaration already has the target 665/// attribute. 666static bool 667DeclHasAttr(const Decl *decl, const Attr *target) { 668 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 669 if (attr->getKind() == target->getKind()) 670 return true; 671 672 return false; 673} 674 675/// MergeAttributes - append attributes from the Old decl to the New one. 676static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 677 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 678 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 679 Attr *NewAttr = attr->clone(C); 680 NewAttr->setInherited(true); 681 New->addAttr(NewAttr); 682 } 683 } 684} 685 686/// Used in MergeFunctionDecl to keep track of function parameters in 687/// C. 688struct GNUCompatibleParamWarning { 689 ParmVarDecl *OldParm; 690 ParmVarDecl *NewParm; 691 QualType PromotedType; 692}; 693 694/// MergeFunctionDecl - We just parsed a function 'New' from 695/// declarator D which has the same name and scope as a previous 696/// declaration 'Old'. Figure out how to resolve this situation, 697/// merging decls or emitting diagnostics as appropriate. 698/// 699/// In C++, New and Old must be declarations that are not 700/// overloaded. Use IsOverload to determine whether New and Old are 701/// overloaded, and to select the Old declaration that New should be 702/// merged with. 703/// 704/// Returns true if there was an error, false otherwise. 705bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 706 assert(!isa<OverloadedFunctionDecl>(OldD) && 707 "Cannot merge with an overloaded function declaration"); 708 709 // Verify the old decl was also a function. 710 FunctionDecl *Old = 0; 711 if (FunctionTemplateDecl *OldFunctionTemplate 712 = dyn_cast<FunctionTemplateDecl>(OldD)) 713 Old = OldFunctionTemplate->getTemplatedDecl(); 714 else 715 Old = dyn_cast<FunctionDecl>(OldD); 716 if (!Old) { 717 Diag(New->getLocation(), diag::err_redefinition_different_kind) 718 << New->getDeclName(); 719 Diag(OldD->getLocation(), diag::note_previous_definition); 720 return true; 721 } 722 723 // Determine whether the previous declaration was a definition, 724 // implicit declaration, or a declaration. 725 diag::kind PrevDiag; 726 if (Old->isThisDeclarationADefinition()) 727 PrevDiag = diag::note_previous_definition; 728 else if (Old->isImplicit()) 729 PrevDiag = diag::note_previous_implicit_declaration; 730 else 731 PrevDiag = diag::note_previous_declaration; 732 733 QualType OldQType = Context.getCanonicalType(Old->getType()); 734 QualType NewQType = Context.getCanonicalType(New->getType()); 735 736 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 737 New->getStorageClass() == FunctionDecl::Static && 738 Old->getStorageClass() != FunctionDecl::Static) { 739 Diag(New->getLocation(), diag::err_static_non_static) 740 << New; 741 Diag(Old->getLocation(), PrevDiag); 742 return true; 743 } 744 745 if (getLangOptions().CPlusPlus) { 746 // (C++98 13.1p2): 747 // Certain function declarations cannot be overloaded: 748 // -- Function declarations that differ only in the return type 749 // cannot be overloaded. 750 QualType OldReturnType 751 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 752 QualType NewReturnType 753 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 754 if (OldReturnType != NewReturnType) { 755 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 756 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 757 return true; 758 } 759 760 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 761 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 762 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 763 NewMethod->getLexicalDeclContext()->isRecord()) { 764 // -- Member function declarations with the same name and the 765 // same parameter types cannot be overloaded if any of them 766 // is a static member function declaration. 767 if (OldMethod->isStatic() || NewMethod->isStatic()) { 768 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 769 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 770 return true; 771 } 772 773 // C++ [class.mem]p1: 774 // [...] A member shall not be declared twice in the 775 // member-specification, except that a nested class or member 776 // class template can be declared and then later defined. 777 unsigned NewDiag; 778 if (isa<CXXConstructorDecl>(OldMethod)) 779 NewDiag = diag::err_constructor_redeclared; 780 else if (isa<CXXDestructorDecl>(NewMethod)) 781 NewDiag = diag::err_destructor_redeclared; 782 else if (isa<CXXConversionDecl>(NewMethod)) 783 NewDiag = diag::err_conv_function_redeclared; 784 else 785 NewDiag = diag::err_member_redeclared; 786 787 Diag(New->getLocation(), NewDiag); 788 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 789 } 790 791 // (C++98 8.3.5p3): 792 // All declarations for a function shall agree exactly in both the 793 // return type and the parameter-type-list. 794 if (OldQType == NewQType) 795 return MergeCompatibleFunctionDecls(New, Old); 796 797 // Fall through for conflicting redeclarations and redefinitions. 798 } 799 800 // C: Function types need to be compatible, not identical. This handles 801 // duplicate function decls like "void f(int); void f(enum X);" properly. 802 if (!getLangOptions().CPlusPlus && 803 Context.typesAreCompatible(OldQType, NewQType)) { 804 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 805 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 806 const FunctionProtoType *OldProto = 0; 807 if (isa<FunctionNoProtoType>(NewFuncType) && 808 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 809 // The old declaration provided a function prototype, but the 810 // new declaration does not. Merge in the prototype. 811 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 812 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 813 OldProto->arg_type_end()); 814 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 815 ParamTypes.data(), ParamTypes.size(), 816 OldProto->isVariadic(), 817 OldProto->getTypeQuals()); 818 New->setType(NewQType); 819 New->setHasInheritedPrototype(); 820 821 // Synthesize a parameter for each argument type. 822 llvm::SmallVector<ParmVarDecl*, 16> Params; 823 for (FunctionProtoType::arg_type_iterator 824 ParamType = OldProto->arg_type_begin(), 825 ParamEnd = OldProto->arg_type_end(); 826 ParamType != ParamEnd; ++ParamType) { 827 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 828 SourceLocation(), 0, 829 *ParamType, /*DInfo=*/0, 830 VarDecl::None, 0); 831 Param->setImplicit(); 832 Params.push_back(Param); 833 } 834 835 New->setParams(Context, Params.data(), Params.size()); 836 } 837 838 return MergeCompatibleFunctionDecls(New, Old); 839 } 840 841 // GNU C permits a K&R definition to follow a prototype declaration 842 // if the declared types of the parameters in the K&R definition 843 // match the types in the prototype declaration, even when the 844 // promoted types of the parameters from the K&R definition differ 845 // from the types in the prototype. GCC then keeps the types from 846 // the prototype. 847 // 848 // If a variadic prototype is followed by a non-variadic K&R definition, 849 // the K&R definition becomes variadic. This is sort of an edge case, but 850 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 851 // C99 6.9.1p8. 852 if (!getLangOptions().CPlusPlus && 853 Old->hasPrototype() && !New->hasPrototype() && 854 New->getType()->getAs<FunctionProtoType>() && 855 Old->getNumParams() == New->getNumParams()) { 856 llvm::SmallVector<QualType, 16> ArgTypes; 857 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 858 const FunctionProtoType *OldProto 859 = Old->getType()->getAs<FunctionProtoType>(); 860 const FunctionProtoType *NewProto 861 = New->getType()->getAs<FunctionProtoType>(); 862 863 // Determine whether this is the GNU C extension. 864 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 865 NewProto->getResultType()); 866 bool LooseCompatible = !MergedReturn.isNull(); 867 for (unsigned Idx = 0, End = Old->getNumParams(); 868 LooseCompatible && Idx != End; ++Idx) { 869 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 870 ParmVarDecl *NewParm = New->getParamDecl(Idx); 871 if (Context.typesAreCompatible(OldParm->getType(), 872 NewProto->getArgType(Idx))) { 873 ArgTypes.push_back(NewParm->getType()); 874 } else if (Context.typesAreCompatible(OldParm->getType(), 875 NewParm->getType())) { 876 GNUCompatibleParamWarning Warn 877 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 878 Warnings.push_back(Warn); 879 ArgTypes.push_back(NewParm->getType()); 880 } else 881 LooseCompatible = false; 882 } 883 884 if (LooseCompatible) { 885 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 886 Diag(Warnings[Warn].NewParm->getLocation(), 887 diag::ext_param_promoted_not_compatible_with_prototype) 888 << Warnings[Warn].PromotedType 889 << Warnings[Warn].OldParm->getType(); 890 Diag(Warnings[Warn].OldParm->getLocation(), 891 diag::note_previous_declaration); 892 } 893 894 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 895 ArgTypes.size(), 896 OldProto->isVariadic(), 0)); 897 return MergeCompatibleFunctionDecls(New, Old); 898 } 899 900 // Fall through to diagnose conflicting types. 901 } 902 903 // A function that has already been declared has been redeclared or defined 904 // with a different type- show appropriate diagnostic 905 if (unsigned BuiltinID = Old->getBuiltinID()) { 906 // The user has declared a builtin function with an incompatible 907 // signature. 908 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 909 // The function the user is redeclaring is a library-defined 910 // function like 'malloc' or 'printf'. Warn about the 911 // redeclaration, then pretend that we don't know about this 912 // library built-in. 913 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 914 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 915 << Old << Old->getType(); 916 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 917 Old->setInvalidDecl(); 918 return false; 919 } 920 921 PrevDiag = diag::note_previous_builtin_declaration; 922 } 923 924 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 925 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 926 return true; 927} 928 929/// \brief Completes the merge of two function declarations that are 930/// known to be compatible. 931/// 932/// This routine handles the merging of attributes and other 933/// properties of function declarations form the old declaration to 934/// the new declaration, once we know that New is in fact a 935/// redeclaration of Old. 936/// 937/// \returns false 938bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 939 // Merge the attributes 940 MergeAttributes(New, Old, Context); 941 942 // Merge the storage class. 943 if (Old->getStorageClass() != FunctionDecl::Extern && 944 Old->getStorageClass() != FunctionDecl::None) 945 New->setStorageClass(Old->getStorageClass()); 946 947 // Merge "pure" flag. 948 if (Old->isPure()) 949 New->setPure(); 950 951 // Merge the "deleted" flag. 952 if (Old->isDeleted()) 953 New->setDeleted(); 954 955 if (getLangOptions().CPlusPlus) 956 return MergeCXXFunctionDecl(New, Old); 957 958 return false; 959} 960 961/// MergeVarDecl - We just parsed a variable 'New' which has the same name 962/// and scope as a previous declaration 'Old'. Figure out how to resolve this 963/// situation, merging decls or emitting diagnostics as appropriate. 964/// 965/// Tentative definition rules (C99 6.9.2p2) are checked by 966/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 967/// definitions here, since the initializer hasn't been attached. 968/// 969void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 970 // If either decl is invalid, make sure the new one is marked invalid and 971 // don't do any other checking. 972 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 973 return New->setInvalidDecl(); 974 975 // Verify the old decl was also a variable. 976 VarDecl *Old = dyn_cast<VarDecl>(OldD); 977 if (!Old) { 978 Diag(New->getLocation(), diag::err_redefinition_different_kind) 979 << New->getDeclName(); 980 Diag(OldD->getLocation(), diag::note_previous_definition); 981 return New->setInvalidDecl(); 982 } 983 984 MergeAttributes(New, Old, Context); 985 986 // Merge the types 987 QualType MergedT; 988 if (getLangOptions().CPlusPlus) { 989 if (Context.hasSameType(New->getType(), Old->getType())) 990 MergedT = New->getType(); 991 // C++ [basic.types]p7: 992 // [...] The declared type of an array object might be an array of 993 // unknown size and therefore be incomplete at one point in a 994 // translation unit and complete later on; [...] 995 else if (Old->getType()->isIncompleteArrayType() && 996 New->getType()->isArrayType()) { 997 CanQual<ArrayType> OldArray 998 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 999 CanQual<ArrayType> NewArray 1000 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1001 if (OldArray->getElementType() == NewArray->getElementType()) 1002 MergedT = New->getType(); 1003 } 1004 } else { 1005 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1006 } 1007 if (MergedT.isNull()) { 1008 Diag(New->getLocation(), diag::err_redefinition_different_type) 1009 << New->getDeclName(); 1010 Diag(Old->getLocation(), diag::note_previous_definition); 1011 return New->setInvalidDecl(); 1012 } 1013 New->setType(MergedT); 1014 1015 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1016 if (New->getStorageClass() == VarDecl::Static && 1017 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1018 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1019 Diag(Old->getLocation(), diag::note_previous_definition); 1020 return New->setInvalidDecl(); 1021 } 1022 // C99 6.2.2p4: 1023 // For an identifier declared with the storage-class specifier 1024 // extern in a scope in which a prior declaration of that 1025 // identifier is visible,23) if the prior declaration specifies 1026 // internal or external linkage, the linkage of the identifier at 1027 // the later declaration is the same as the linkage specified at 1028 // the prior declaration. If no prior declaration is visible, or 1029 // if the prior declaration specifies no linkage, then the 1030 // identifier has external linkage. 1031 if (New->hasExternalStorage() && Old->hasLinkage()) 1032 /* Okay */; 1033 else if (New->getStorageClass() != VarDecl::Static && 1034 Old->getStorageClass() == VarDecl::Static) { 1035 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1036 Diag(Old->getLocation(), diag::note_previous_definition); 1037 return New->setInvalidDecl(); 1038 } 1039 1040 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1041 1042 // FIXME: The test for external storage here seems wrong? We still 1043 // need to check for mismatches. 1044 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1045 // Don't complain about out-of-line definitions of static members. 1046 !(Old->getLexicalDeclContext()->isRecord() && 1047 !New->getLexicalDeclContext()->isRecord())) { 1048 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1049 Diag(Old->getLocation(), diag::note_previous_definition); 1050 return New->setInvalidDecl(); 1051 } 1052 1053 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1054 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1055 Diag(Old->getLocation(), diag::note_previous_definition); 1056 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1057 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1058 Diag(Old->getLocation(), diag::note_previous_definition); 1059 } 1060 1061 // Keep a chain of previous declarations. 1062 New->setPreviousDeclaration(Old); 1063} 1064 1065/// CheckFallThrough - Check that we don't fall off the end of a 1066/// Statement that should return a value. 1067/// 1068/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1069/// MaybeFallThrough iff we might or might not fall off the end, 1070/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1071/// return. We assume NeverFallThrough iff we never fall off the end of the 1072/// statement but we may return. We assume that functions not marked noreturn 1073/// will return. 1074Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1075 // FIXME: Eventually share this CFG object when we have other warnings based 1076 // of the CFG. This can be done using AnalysisContext. 1077 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1078 1079 // FIXME: They should never return 0, fix that, delete this code. 1080 if (cfg == 0) 1081 // FIXME: This should be NeverFallThrough 1082 return NeverFallThroughOrReturn; 1083 // The CFG leaves in dead things, and we don't want to dead code paths to 1084 // confuse us, so we mark all live things first. 1085 std::queue<CFGBlock*> workq; 1086 llvm::BitVector live(cfg->getNumBlockIDs()); 1087 // Prep work queue 1088 workq.push(&cfg->getEntry()); 1089 // Solve 1090 while (!workq.empty()) { 1091 CFGBlock *item = workq.front(); 1092 workq.pop(); 1093 live.set(item->getBlockID()); 1094 for (CFGBlock::succ_iterator I=item->succ_begin(), 1095 E=item->succ_end(); 1096 I != E; 1097 ++I) { 1098 if ((*I) && !live[(*I)->getBlockID()]) { 1099 live.set((*I)->getBlockID()); 1100 workq.push(*I); 1101 } 1102 } 1103 } 1104 1105 // Now we know what is live, we check the live precessors of the exit block 1106 // and look for fall through paths, being careful to ignore normal returns, 1107 // and exceptional paths. 1108 bool HasLiveReturn = false; 1109 bool HasFakeEdge = false; 1110 bool HasPlainEdge = false; 1111 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1112 E = cfg->getExit().pred_end(); 1113 I != E; 1114 ++I) { 1115 CFGBlock& B = **I; 1116 if (!live[B.getBlockID()]) 1117 continue; 1118 if (B.size() == 0) { 1119 // A labeled empty statement, or the entry block... 1120 HasPlainEdge = true; 1121 continue; 1122 } 1123 Stmt *S = B[B.size()-1]; 1124 if (isa<ReturnStmt>(S)) { 1125 HasLiveReturn = true; 1126 continue; 1127 } 1128 if (isa<ObjCAtThrowStmt>(S)) { 1129 HasFakeEdge = true; 1130 continue; 1131 } 1132 if (isa<CXXThrowExpr>(S)) { 1133 HasFakeEdge = true; 1134 continue; 1135 } 1136 bool NoReturnEdge = false; 1137 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1138 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1139 if (CEE->getType().getNoReturnAttr()) { 1140 NoReturnEdge = true; 1141 HasFakeEdge = true; 1142 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1143 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1144 if (FD->hasAttr<NoReturnAttr>()) { 1145 NoReturnEdge = true; 1146 HasFakeEdge = true; 1147 } 1148 } 1149 } 1150 } 1151 // FIXME: Add noreturn message sends. 1152 if (NoReturnEdge == false) 1153 HasPlainEdge = true; 1154 } 1155 if (!HasPlainEdge) { 1156 if (HasLiveReturn) 1157 return NeverFallThrough; 1158 return NeverFallThroughOrReturn; 1159 } 1160 if (HasFakeEdge || HasLiveReturn) 1161 return MaybeFallThrough; 1162 // This says AlwaysFallThrough for calls to functions that are not marked 1163 // noreturn, that don't return. If people would like this warning to be more 1164 // accurate, such functions should be marked as noreturn. 1165 return AlwaysFallThrough; 1166} 1167 1168/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1169/// function that should return a value. Check that we don't fall off the end 1170/// of a noreturn function. We assume that functions and blocks not marked 1171/// noreturn will return. 1172void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1173 // FIXME: Would be nice if we had a better way to control cascading errors, 1174 // but for now, avoid them. The problem is that when Parse sees: 1175 // int foo() { return a; } 1176 // The return is eaten and the Sema code sees just: 1177 // int foo() { } 1178 // which this code would then warn about. 1179 if (getDiagnostics().hasErrorOccurred()) 1180 return; 1181 1182 bool ReturnsVoid = false; 1183 bool HasNoReturn = false; 1184 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1185 // If the result type of the function is a dependent type, we don't know 1186 // whether it will be void or not, so don't 1187 if (FD->getResultType()->isDependentType()) 1188 return; 1189 if (FD->getResultType()->isVoidType()) 1190 ReturnsVoid = true; 1191 if (FD->hasAttr<NoReturnAttr>()) 1192 HasNoReturn = true; 1193 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1194 if (MD->getResultType()->isVoidType()) 1195 ReturnsVoid = true; 1196 if (MD->hasAttr<NoReturnAttr>()) 1197 HasNoReturn = true; 1198 } 1199 1200 // Short circuit for compilation speed. 1201 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1202 == Diagnostic::Ignored || ReturnsVoid) 1203 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1204 == Diagnostic::Ignored || !HasNoReturn) 1205 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1206 == Diagnostic::Ignored || !ReturnsVoid)) 1207 return; 1208 // FIXME: Function try block 1209 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1210 switch (CheckFallThrough(Body)) { 1211 case MaybeFallThrough: 1212 if (HasNoReturn) 1213 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1214 else if (!ReturnsVoid) 1215 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1216 break; 1217 case AlwaysFallThrough: 1218 if (HasNoReturn) 1219 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1220 else if (!ReturnsVoid) 1221 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1222 break; 1223 case NeverFallThroughOrReturn: 1224 if (ReturnsVoid && !HasNoReturn) 1225 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1226 break; 1227 case NeverFallThrough: 1228 break; 1229 } 1230 } 1231} 1232 1233/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1234/// that should return a value. Check that we don't fall off the end of a 1235/// noreturn block. We assume that functions and blocks not marked noreturn 1236/// will return. 1237void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1238 // FIXME: Would be nice if we had a better way to control cascading errors, 1239 // but for now, avoid them. The problem is that when Parse sees: 1240 // int foo() { return a; } 1241 // The return is eaten and the Sema code sees just: 1242 // int foo() { } 1243 // which this code would then warn about. 1244 if (getDiagnostics().hasErrorOccurred()) 1245 return; 1246 bool ReturnsVoid = false; 1247 bool HasNoReturn = false; 1248 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1249 if (FT->getResultType()->isVoidType()) 1250 ReturnsVoid = true; 1251 if (FT->getNoReturnAttr()) 1252 HasNoReturn = true; 1253 } 1254 1255 // Short circuit for compilation speed. 1256 if (ReturnsVoid 1257 && !HasNoReturn 1258 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1259 == Diagnostic::Ignored || !ReturnsVoid)) 1260 return; 1261 // FIXME: Funtion try block 1262 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1263 switch (CheckFallThrough(Body)) { 1264 case MaybeFallThrough: 1265 if (HasNoReturn) 1266 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1267 else if (!ReturnsVoid) 1268 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1269 break; 1270 case AlwaysFallThrough: 1271 if (HasNoReturn) 1272 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1273 else if (!ReturnsVoid) 1274 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1275 break; 1276 case NeverFallThroughOrReturn: 1277 if (ReturnsVoid) 1278 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1279 break; 1280 case NeverFallThrough: 1281 break; 1282 } 1283 } 1284} 1285 1286/// CheckParmsForFunctionDef - Check that the parameters of the given 1287/// function are appropriate for the definition of a function. This 1288/// takes care of any checks that cannot be performed on the 1289/// declaration itself, e.g., that the types of each of the function 1290/// parameters are complete. 1291bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1292 bool HasInvalidParm = false; 1293 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1294 ParmVarDecl *Param = FD->getParamDecl(p); 1295 1296 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1297 // function declarator that is part of a function definition of 1298 // that function shall not have incomplete type. 1299 // 1300 // This is also C++ [dcl.fct]p6. 1301 if (!Param->isInvalidDecl() && 1302 RequireCompleteType(Param->getLocation(), Param->getType(), 1303 diag::err_typecheck_decl_incomplete_type)) { 1304 Param->setInvalidDecl(); 1305 HasInvalidParm = true; 1306 } 1307 1308 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1309 // declaration of each parameter shall include an identifier. 1310 if (Param->getIdentifier() == 0 && 1311 !Param->isImplicit() && 1312 !getLangOptions().CPlusPlus) 1313 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1314 } 1315 1316 return HasInvalidParm; 1317} 1318 1319/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1320/// no declarator (e.g. "struct foo;") is parsed. 1321Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1322 // FIXME: Error on auto/register at file scope 1323 // FIXME: Error on inline/virtual/explicit 1324 // FIXME: Error on invalid restrict 1325 // FIXME: Warn on useless __thread 1326 // FIXME: Warn on useless const/volatile 1327 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1328 // FIXME: Warn on useless attributes 1329 Decl *TagD = 0; 1330 TagDecl *Tag = 0; 1331 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1332 DS.getTypeSpecType() == DeclSpec::TST_struct || 1333 DS.getTypeSpecType() == DeclSpec::TST_union || 1334 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1335 TagD = static_cast<Decl *>(DS.getTypeRep()); 1336 1337 if (!TagD) // We probably had an error 1338 return DeclPtrTy(); 1339 1340 // Note that the above type specs guarantee that the 1341 // type rep is a Decl, whereas in many of the others 1342 // it's a Type. 1343 Tag = dyn_cast<TagDecl>(TagD); 1344 } 1345 1346 if (DS.isFriendSpecified()) { 1347 // If we're dealing with a class template decl, assume that the 1348 // template routines are handling it. 1349 if (TagD && isa<ClassTemplateDecl>(TagD)) 1350 return DeclPtrTy(); 1351 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1352 } 1353 1354 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1355 // If there are attributes in the DeclSpec, apply them to the record. 1356 if (const AttributeList *AL = DS.getAttributes()) 1357 ProcessDeclAttributeList(S, Record, AL); 1358 1359 if (!Record->getDeclName() && Record->isDefinition() && 1360 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1361 if (getLangOptions().CPlusPlus || 1362 Record->getDeclContext()->isRecord()) 1363 return BuildAnonymousStructOrUnion(S, DS, Record); 1364 1365 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1366 << DS.getSourceRange(); 1367 } 1368 1369 // Microsoft allows unnamed struct/union fields. Don't complain 1370 // about them. 1371 // FIXME: Should we support Microsoft's extensions in this area? 1372 if (Record->getDeclName() && getLangOptions().Microsoft) 1373 return DeclPtrTy::make(Tag); 1374 } 1375 1376 if (!DS.isMissingDeclaratorOk() && 1377 DS.getTypeSpecType() != DeclSpec::TST_error) { 1378 // Warn about typedefs of enums without names, since this is an 1379 // extension in both Microsoft an GNU. 1380 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1381 Tag && isa<EnumDecl>(Tag)) { 1382 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1383 << DS.getSourceRange(); 1384 return DeclPtrTy::make(Tag); 1385 } 1386 1387 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1388 << DS.getSourceRange(); 1389 return DeclPtrTy(); 1390 } 1391 1392 return DeclPtrTy::make(Tag); 1393} 1394 1395/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1396/// anonymous struct or union AnonRecord into the owning context Owner 1397/// and scope S. This routine will be invoked just after we realize 1398/// that an unnamed union or struct is actually an anonymous union or 1399/// struct, e.g., 1400/// 1401/// @code 1402/// union { 1403/// int i; 1404/// float f; 1405/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1406/// // f into the surrounding scope.x 1407/// @endcode 1408/// 1409/// This routine is recursive, injecting the names of nested anonymous 1410/// structs/unions into the owning context and scope as well. 1411bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1412 RecordDecl *AnonRecord) { 1413 bool Invalid = false; 1414 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1415 FEnd = AnonRecord->field_end(); 1416 F != FEnd; ++F) { 1417 if ((*F)->getDeclName()) { 1418 LookupResult R; 1419 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1420 LookupOrdinaryName, true); 1421 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1422 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1423 // C++ [class.union]p2: 1424 // The names of the members of an anonymous union shall be 1425 // distinct from the names of any other entity in the 1426 // scope in which the anonymous union is declared. 1427 unsigned diagKind 1428 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1429 : diag::err_anonymous_struct_member_redecl; 1430 Diag((*F)->getLocation(), diagKind) 1431 << (*F)->getDeclName(); 1432 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1433 Invalid = true; 1434 } else { 1435 // C++ [class.union]p2: 1436 // For the purpose of name lookup, after the anonymous union 1437 // definition, the members of the anonymous union are 1438 // considered to have been defined in the scope in which the 1439 // anonymous union is declared. 1440 Owner->makeDeclVisibleInContext(*F); 1441 S->AddDecl(DeclPtrTy::make(*F)); 1442 IdResolver.AddDecl(*F); 1443 } 1444 } else if (const RecordType *InnerRecordType 1445 = (*F)->getType()->getAs<RecordType>()) { 1446 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1447 if (InnerRecord->isAnonymousStructOrUnion()) 1448 Invalid = Invalid || 1449 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1450 } 1451 } 1452 1453 return Invalid; 1454} 1455 1456/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1457/// anonymous structure or union. Anonymous unions are a C++ feature 1458/// (C++ [class.union]) and a GNU C extension; anonymous structures 1459/// are a GNU C and GNU C++ extension. 1460Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1461 RecordDecl *Record) { 1462 DeclContext *Owner = Record->getDeclContext(); 1463 1464 // Diagnose whether this anonymous struct/union is an extension. 1465 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1466 Diag(Record->getLocation(), diag::ext_anonymous_union); 1467 else if (!Record->isUnion()) 1468 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1469 1470 // C and C++ require different kinds of checks for anonymous 1471 // structs/unions. 1472 bool Invalid = false; 1473 if (getLangOptions().CPlusPlus) { 1474 const char* PrevSpec = 0; 1475 unsigned DiagID; 1476 // C++ [class.union]p3: 1477 // Anonymous unions declared in a named namespace or in the 1478 // global namespace shall be declared static. 1479 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1480 (isa<TranslationUnitDecl>(Owner) || 1481 (isa<NamespaceDecl>(Owner) && 1482 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1483 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1484 Invalid = true; 1485 1486 // Recover by adding 'static'. 1487 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1488 PrevSpec, DiagID); 1489 } 1490 // C++ [class.union]p3: 1491 // A storage class is not allowed in a declaration of an 1492 // anonymous union in a class scope. 1493 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1494 isa<RecordDecl>(Owner)) { 1495 Diag(DS.getStorageClassSpecLoc(), 1496 diag::err_anonymous_union_with_storage_spec); 1497 Invalid = true; 1498 1499 // Recover by removing the storage specifier. 1500 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1501 PrevSpec, DiagID); 1502 } 1503 1504 // C++ [class.union]p2: 1505 // The member-specification of an anonymous union shall only 1506 // define non-static data members. [Note: nested types and 1507 // functions cannot be declared within an anonymous union. ] 1508 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1509 MemEnd = Record->decls_end(); 1510 Mem != MemEnd; ++Mem) { 1511 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1512 // C++ [class.union]p3: 1513 // An anonymous union shall not have private or protected 1514 // members (clause 11). 1515 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1516 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1517 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1518 Invalid = true; 1519 } 1520 } else if ((*Mem)->isImplicit()) { 1521 // Any implicit members are fine. 1522 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1523 // This is a type that showed up in an 1524 // elaborated-type-specifier inside the anonymous struct or 1525 // union, but which actually declares a type outside of the 1526 // anonymous struct or union. It's okay. 1527 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1528 if (!MemRecord->isAnonymousStructOrUnion() && 1529 MemRecord->getDeclName()) { 1530 // This is a nested type declaration. 1531 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1532 << (int)Record->isUnion(); 1533 Invalid = true; 1534 } 1535 } else { 1536 // We have something that isn't a non-static data 1537 // member. Complain about it. 1538 unsigned DK = diag::err_anonymous_record_bad_member; 1539 if (isa<TypeDecl>(*Mem)) 1540 DK = diag::err_anonymous_record_with_type; 1541 else if (isa<FunctionDecl>(*Mem)) 1542 DK = diag::err_anonymous_record_with_function; 1543 else if (isa<VarDecl>(*Mem)) 1544 DK = diag::err_anonymous_record_with_static; 1545 Diag((*Mem)->getLocation(), DK) 1546 << (int)Record->isUnion(); 1547 Invalid = true; 1548 } 1549 } 1550 } 1551 1552 if (!Record->isUnion() && !Owner->isRecord()) { 1553 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1554 << (int)getLangOptions().CPlusPlus; 1555 Invalid = true; 1556 } 1557 1558 // Mock up a declarator. 1559 Declarator Dc(DS, Declarator::TypeNameContext); 1560 DeclaratorInfo *DInfo = 0; 1561 GetTypeForDeclarator(Dc, S, &DInfo); 1562 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1563 1564 // Create a declaration for this anonymous struct/union. 1565 NamedDecl *Anon = 0; 1566 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1567 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1568 /*IdentifierInfo=*/0, 1569 Context.getTypeDeclType(Record), 1570 DInfo, 1571 /*BitWidth=*/0, /*Mutable=*/false); 1572 Anon->setAccess(AS_public); 1573 if (getLangOptions().CPlusPlus) 1574 FieldCollector->Add(cast<FieldDecl>(Anon)); 1575 } else { 1576 VarDecl::StorageClass SC; 1577 switch (DS.getStorageClassSpec()) { 1578 default: assert(0 && "Unknown storage class!"); 1579 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1580 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1581 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1582 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1583 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1584 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1585 case DeclSpec::SCS_mutable: 1586 // mutable can only appear on non-static class members, so it's always 1587 // an error here 1588 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1589 Invalid = true; 1590 SC = VarDecl::None; 1591 break; 1592 } 1593 1594 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1595 /*IdentifierInfo=*/0, 1596 Context.getTypeDeclType(Record), 1597 DInfo, 1598 SC); 1599 } 1600 Anon->setImplicit(); 1601 1602 // Add the anonymous struct/union object to the current 1603 // context. We'll be referencing this object when we refer to one of 1604 // its members. 1605 Owner->addDecl(Anon); 1606 1607 // Inject the members of the anonymous struct/union into the owning 1608 // context and into the identifier resolver chain for name lookup 1609 // purposes. 1610 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1611 Invalid = true; 1612 1613 // Mark this as an anonymous struct/union type. Note that we do not 1614 // do this until after we have already checked and injected the 1615 // members of this anonymous struct/union type, because otherwise 1616 // the members could be injected twice: once by DeclContext when it 1617 // builds its lookup table, and once by 1618 // InjectAnonymousStructOrUnionMembers. 1619 Record->setAnonymousStructOrUnion(true); 1620 1621 if (Invalid) 1622 Anon->setInvalidDecl(); 1623 1624 return DeclPtrTy::make(Anon); 1625} 1626 1627 1628/// GetNameForDeclarator - Determine the full declaration name for the 1629/// given Declarator. 1630DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1631 return GetNameFromUnqualifiedId(D.getName()); 1632} 1633 1634/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1635DeclarationName Sema::GetNameFromUnqualifiedId(UnqualifiedId &Name) { 1636 switch (Name.getKind()) { 1637 case UnqualifiedId::IK_Identifier: 1638 return DeclarationName(Name.Identifier); 1639 1640 case UnqualifiedId::IK_OperatorFunctionId: 1641 return Context.DeclarationNames.getCXXOperatorName( 1642 Name.OperatorFunctionId.Operator); 1643 1644 case UnqualifiedId::IK_ConversionFunctionId: { 1645 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1646 if (Ty.isNull()) 1647 return DeclarationName(); 1648 1649 return Context.DeclarationNames.getCXXConversionFunctionName( 1650 Context.getCanonicalType(Ty)); 1651 } 1652 1653 case UnqualifiedId::IK_ConstructorName: { 1654 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1655 if (Ty.isNull()) 1656 return DeclarationName(); 1657 1658 return Context.DeclarationNames.getCXXConstructorName( 1659 Context.getCanonicalType(Ty)); 1660 } 1661 1662 case UnqualifiedId::IK_DestructorName: { 1663 QualType Ty = GetTypeFromParser(Name.DestructorName); 1664 if (Ty.isNull()) 1665 return DeclarationName(); 1666 1667 return Context.DeclarationNames.getCXXDestructorName( 1668 Context.getCanonicalType(Ty)); 1669 } 1670 1671 case UnqualifiedId::IK_TemplateId: { 1672 TemplateName TName 1673 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1674 if (TemplateDecl *Template = TName.getAsTemplateDecl()) 1675 return Template->getDeclName(); 1676 if (OverloadedFunctionDecl *Ovl = TName.getAsOverloadedFunctionDecl()) 1677 return Ovl->getDeclName(); 1678 1679 return DeclarationName(); 1680 } 1681 } 1682 1683 assert(false && "Unknown name kind"); 1684 return DeclarationName(); 1685} 1686 1687/// isNearlyMatchingFunction - Determine whether the C++ functions 1688/// Declaration and Definition are "nearly" matching. This heuristic 1689/// is used to improve diagnostics in the case where an out-of-line 1690/// function definition doesn't match any declaration within 1691/// the class or namespace. 1692static bool isNearlyMatchingFunction(ASTContext &Context, 1693 FunctionDecl *Declaration, 1694 FunctionDecl *Definition) { 1695 if (Declaration->param_size() != Definition->param_size()) 1696 return false; 1697 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1698 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1699 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1700 1701 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1702 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1703 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1704 return false; 1705 } 1706 1707 return true; 1708} 1709 1710Sema::DeclPtrTy 1711Sema::HandleDeclarator(Scope *S, Declarator &D, 1712 MultiTemplateParamsArg TemplateParamLists, 1713 bool IsFunctionDefinition) { 1714 DeclarationName Name = GetNameForDeclarator(D); 1715 1716 // All of these full declarators require an identifier. If it doesn't have 1717 // one, the ParsedFreeStandingDeclSpec action should be used. 1718 if (!Name) { 1719 if (!D.isInvalidType()) // Reject this if we think it is valid. 1720 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1721 diag::err_declarator_need_ident) 1722 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1723 return DeclPtrTy(); 1724 } 1725 1726 // The scope passed in may not be a decl scope. Zip up the scope tree until 1727 // we find one that is. 1728 while ((S->getFlags() & Scope::DeclScope) == 0 || 1729 (S->getFlags() & Scope::TemplateParamScope) != 0) 1730 S = S->getParent(); 1731 1732 // If this is an out-of-line definition of a member of a class template 1733 // or class template partial specialization, we may need to rebuild the 1734 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1735 // for more information. 1736 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1737 // handle expressions properly. 1738 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1739 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1740 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1741 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1742 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1743 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1744 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1745 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1746 // FIXME: Preserve type source info. 1747 QualType T = GetTypeFromParser(DS.getTypeRep()); 1748 EnterDeclaratorContext(S, DC); 1749 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1750 ExitDeclaratorContext(S); 1751 if (T.isNull()) 1752 return DeclPtrTy(); 1753 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1754 } 1755 } 1756 1757 DeclContext *DC; 1758 NamedDecl *PrevDecl; 1759 NamedDecl *New; 1760 1761 DeclaratorInfo *DInfo = 0; 1762 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1763 1764 // See if this is a redefinition of a variable in the same scope. 1765 if (D.getCXXScopeSpec().isInvalid()) { 1766 DC = CurContext; 1767 PrevDecl = 0; 1768 D.setInvalidType(); 1769 } else if (!D.getCXXScopeSpec().isSet()) { 1770 LookupNameKind NameKind = LookupOrdinaryName; 1771 1772 // If the declaration we're planning to build will be a function 1773 // or object with linkage, then look for another declaration with 1774 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1775 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1776 /* Do nothing*/; 1777 else if (R->isFunctionType()) { 1778 if (CurContext->isFunctionOrMethod() || 1779 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1780 NameKind = LookupRedeclarationWithLinkage; 1781 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1782 NameKind = LookupRedeclarationWithLinkage; 1783 else if (CurContext->getLookupContext()->isTranslationUnit() && 1784 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1785 NameKind = LookupRedeclarationWithLinkage; 1786 1787 DC = CurContext; 1788 LookupResult R; 1789 LookupName(R, S, Name, NameKind, true, 1790 NameKind == LookupRedeclarationWithLinkage, 1791 D.getIdentifierLoc()); 1792 PrevDecl = R.getAsSingleDecl(Context); 1793 } else { // Something like "int foo::x;" 1794 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1795 1796 if (!DC) { 1797 // If we could not compute the declaration context, it's because the 1798 // declaration context is dependent but does not refer to a class, 1799 // class template, or class template partial specialization. Complain 1800 // and return early, to avoid the coming semantic disaster. 1801 Diag(D.getIdentifierLoc(), 1802 diag::err_template_qualified_declarator_no_match) 1803 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1804 << D.getCXXScopeSpec().getRange(); 1805 return DeclPtrTy(); 1806 } 1807 1808 if (!DC->isDependentContext() && 1809 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1810 return DeclPtrTy(); 1811 1812 LookupResult Res; 1813 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1814 PrevDecl = Res.getAsSingleDecl(Context); 1815 1816 // C++ 7.3.1.2p2: 1817 // Members (including explicit specializations of templates) of a named 1818 // namespace can also be defined outside that namespace by explicit 1819 // qualification of the name being defined, provided that the entity being 1820 // defined was already declared in the namespace and the definition appears 1821 // after the point of declaration in a namespace that encloses the 1822 // declarations namespace. 1823 // 1824 // Note that we only check the context at this point. We don't yet 1825 // have enough information to make sure that PrevDecl is actually 1826 // the declaration we want to match. For example, given: 1827 // 1828 // class X { 1829 // void f(); 1830 // void f(float); 1831 // }; 1832 // 1833 // void X::f(int) { } // ill-formed 1834 // 1835 // In this case, PrevDecl will point to the overload set 1836 // containing the two f's declared in X, but neither of them 1837 // matches. 1838 1839 // First check whether we named the global scope. 1840 if (isa<TranslationUnitDecl>(DC)) { 1841 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1842 << Name << D.getCXXScopeSpec().getRange(); 1843 } else { 1844 DeclContext *Cur = CurContext; 1845 while (isa<LinkageSpecDecl>(Cur)) 1846 Cur = Cur->getParent(); 1847 if (!Cur->Encloses(DC)) { 1848 // The qualifying scope doesn't enclose the original declaration. 1849 // Emit diagnostic based on current scope. 1850 SourceLocation L = D.getIdentifierLoc(); 1851 SourceRange R = D.getCXXScopeSpec().getRange(); 1852 if (isa<FunctionDecl>(Cur)) 1853 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1854 else 1855 Diag(L, diag::err_invalid_declarator_scope) 1856 << Name << cast<NamedDecl>(DC) << R; 1857 D.setInvalidType(); 1858 } 1859 } 1860 } 1861 1862 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1863 // Maybe we will complain about the shadowed template parameter. 1864 if (!D.isInvalidType()) 1865 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1866 D.setInvalidType(); 1867 1868 // Just pretend that we didn't see the previous declaration. 1869 PrevDecl = 0; 1870 } 1871 1872 // In C++, the previous declaration we find might be a tag type 1873 // (class or enum). In this case, the new declaration will hide the 1874 // tag type. Note that this does does not apply if we're declaring a 1875 // typedef (C++ [dcl.typedef]p4). 1876 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1877 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1878 PrevDecl = 0; 1879 1880 bool Redeclaration = false; 1881 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1882 if (TemplateParamLists.size()) { 1883 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1884 return DeclPtrTy(); 1885 } 1886 1887 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1888 } else if (R->isFunctionType()) { 1889 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1890 move(TemplateParamLists), 1891 IsFunctionDefinition, Redeclaration); 1892 } else { 1893 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1894 move(TemplateParamLists), 1895 Redeclaration); 1896 } 1897 1898 if (New == 0) 1899 return DeclPtrTy(); 1900 1901 // If this has an identifier and is not an invalid redeclaration or 1902 // function template specialization, add it to the scope stack. 1903 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1904 !(isa<FunctionDecl>(New) && 1905 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1906 PushOnScopeChains(New, S); 1907 1908 return DeclPtrTy::make(New); 1909} 1910 1911/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1912/// types into constant array types in certain situations which would otherwise 1913/// be errors (for GCC compatibility). 1914static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1915 ASTContext &Context, 1916 bool &SizeIsNegative) { 1917 // This method tries to turn a variable array into a constant 1918 // array even when the size isn't an ICE. This is necessary 1919 // for compatibility with code that depends on gcc's buggy 1920 // constant expression folding, like struct {char x[(int)(char*)2];} 1921 SizeIsNegative = false; 1922 1923 QualifierCollector Qs; 1924 const Type *Ty = Qs.strip(T); 1925 1926 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1927 QualType Pointee = PTy->getPointeeType(); 1928 QualType FixedType = 1929 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1930 if (FixedType.isNull()) return FixedType; 1931 FixedType = Context.getPointerType(FixedType); 1932 return Qs.apply(FixedType); 1933 } 1934 1935 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1936 if (!VLATy) 1937 return QualType(); 1938 // FIXME: We should probably handle this case 1939 if (VLATy->getElementType()->isVariablyModifiedType()) 1940 return QualType(); 1941 1942 Expr::EvalResult EvalResult; 1943 if (!VLATy->getSizeExpr() || 1944 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1945 !EvalResult.Val.isInt()) 1946 return QualType(); 1947 1948 llvm::APSInt &Res = EvalResult.Val.getInt(); 1949 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1950 // TODO: preserve the size expression in declarator info 1951 return Context.getConstantArrayType(VLATy->getElementType(), 1952 Res, ArrayType::Normal, 0); 1953 } 1954 1955 SizeIsNegative = true; 1956 return QualType(); 1957} 1958 1959/// \brief Register the given locally-scoped external C declaration so 1960/// that it can be found later for redeclarations 1961void 1962Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1963 Scope *S) { 1964 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1965 "Decl is not a locally-scoped decl!"); 1966 // Note that we have a locally-scoped external with this name. 1967 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1968 1969 if (!PrevDecl) 1970 return; 1971 1972 // If there was a previous declaration of this variable, it may be 1973 // in our identifier chain. Update the identifier chain with the new 1974 // declaration. 1975 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1976 // The previous declaration was found on the identifer resolver 1977 // chain, so remove it from its scope. 1978 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1979 S = S->getParent(); 1980 1981 if (S) 1982 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1983 } 1984} 1985 1986/// \brief Diagnose function specifiers on a declaration of an identifier that 1987/// does not identify a function. 1988void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1989 // FIXME: We should probably indicate the identifier in question to avoid 1990 // confusion for constructs like "inline int a(), b;" 1991 if (D.getDeclSpec().isInlineSpecified()) 1992 Diag(D.getDeclSpec().getInlineSpecLoc(), 1993 diag::err_inline_non_function); 1994 1995 if (D.getDeclSpec().isVirtualSpecified()) 1996 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1997 diag::err_virtual_non_function); 1998 1999 if (D.getDeclSpec().isExplicitSpecified()) 2000 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2001 diag::err_explicit_non_function); 2002} 2003 2004NamedDecl* 2005Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2006 QualType R, DeclaratorInfo *DInfo, 2007 NamedDecl* PrevDecl, bool &Redeclaration) { 2008 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2009 if (D.getCXXScopeSpec().isSet()) { 2010 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2011 << D.getCXXScopeSpec().getRange(); 2012 D.setInvalidType(); 2013 // Pretend we didn't see the scope specifier. 2014 DC = 0; 2015 } 2016 2017 if (getLangOptions().CPlusPlus) { 2018 // Check that there are no default arguments (C++ only). 2019 CheckExtraCXXDefaultArguments(D); 2020 } 2021 2022 DiagnoseFunctionSpecifiers(D); 2023 2024 if (D.getDeclSpec().isThreadSpecified()) 2025 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2026 2027 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 2028 if (!NewTD) return 0; 2029 2030 // Handle attributes prior to checking for duplicates in MergeVarDecl 2031 ProcessDeclAttributes(S, NewTD, D); 2032 // Merge the decl with the existing one if appropriate. If the decl is 2033 // in an outer scope, it isn't the same thing. 2034 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2035 Redeclaration = true; 2036 MergeTypeDefDecl(NewTD, PrevDecl); 2037 } 2038 2039 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2040 // then it shall have block scope. 2041 QualType T = NewTD->getUnderlyingType(); 2042 if (T->isVariablyModifiedType()) { 2043 CurFunctionNeedsScopeChecking = true; 2044 2045 if (S->getFnParent() == 0) { 2046 bool SizeIsNegative; 2047 QualType FixedTy = 2048 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2049 if (!FixedTy.isNull()) { 2050 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2051 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2052 } else { 2053 if (SizeIsNegative) 2054 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2055 else if (T->isVariableArrayType()) 2056 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2057 else 2058 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2059 NewTD->setInvalidDecl(); 2060 } 2061 } 2062 } 2063 2064 // If this is the C FILE type, notify the AST context. 2065 if (IdentifierInfo *II = NewTD->getIdentifier()) 2066 if (!NewTD->isInvalidDecl() && 2067 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2068 if (II->isStr("FILE")) 2069 Context.setFILEDecl(NewTD); 2070 else if (II->isStr("jmp_buf")) 2071 Context.setjmp_bufDecl(NewTD); 2072 else if (II->isStr("sigjmp_buf")) 2073 Context.setsigjmp_bufDecl(NewTD); 2074 } 2075 2076 return NewTD; 2077} 2078 2079/// \brief Determines whether the given declaration is an out-of-scope 2080/// previous declaration. 2081/// 2082/// This routine should be invoked when name lookup has found a 2083/// previous declaration (PrevDecl) that is not in the scope where a 2084/// new declaration by the same name is being introduced. If the new 2085/// declaration occurs in a local scope, previous declarations with 2086/// linkage may still be considered previous declarations (C99 2087/// 6.2.2p4-5, C++ [basic.link]p6). 2088/// 2089/// \param PrevDecl the previous declaration found by name 2090/// lookup 2091/// 2092/// \param DC the context in which the new declaration is being 2093/// declared. 2094/// 2095/// \returns true if PrevDecl is an out-of-scope previous declaration 2096/// for a new delcaration with the same name. 2097static bool 2098isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2099 ASTContext &Context) { 2100 if (!PrevDecl) 2101 return 0; 2102 2103 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2104 // case we need to check each of the overloaded functions. 2105 if (!PrevDecl->hasLinkage()) 2106 return false; 2107 2108 if (Context.getLangOptions().CPlusPlus) { 2109 // C++ [basic.link]p6: 2110 // If there is a visible declaration of an entity with linkage 2111 // having the same name and type, ignoring entities declared 2112 // outside the innermost enclosing namespace scope, the block 2113 // scope declaration declares that same entity and receives the 2114 // linkage of the previous declaration. 2115 DeclContext *OuterContext = DC->getLookupContext(); 2116 if (!OuterContext->isFunctionOrMethod()) 2117 // This rule only applies to block-scope declarations. 2118 return false; 2119 else { 2120 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2121 if (PrevOuterContext->isRecord()) 2122 // We found a member function: ignore it. 2123 return false; 2124 else { 2125 // Find the innermost enclosing namespace for the new and 2126 // previous declarations. 2127 while (!OuterContext->isFileContext()) 2128 OuterContext = OuterContext->getParent(); 2129 while (!PrevOuterContext->isFileContext()) 2130 PrevOuterContext = PrevOuterContext->getParent(); 2131 2132 // The previous declaration is in a different namespace, so it 2133 // isn't the same function. 2134 if (OuterContext->getPrimaryContext() != 2135 PrevOuterContext->getPrimaryContext()) 2136 return false; 2137 } 2138 } 2139 } 2140 2141 return true; 2142} 2143 2144NamedDecl* 2145Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2146 QualType R, DeclaratorInfo *DInfo, 2147 NamedDecl* PrevDecl, 2148 MultiTemplateParamsArg TemplateParamLists, 2149 bool &Redeclaration) { 2150 DeclarationName Name = GetNameForDeclarator(D); 2151 2152 // Check that there are no default arguments (C++ only). 2153 if (getLangOptions().CPlusPlus) 2154 CheckExtraCXXDefaultArguments(D); 2155 2156 VarDecl *NewVD; 2157 VarDecl::StorageClass SC; 2158 switch (D.getDeclSpec().getStorageClassSpec()) { 2159 default: assert(0 && "Unknown storage class!"); 2160 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2161 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2162 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2163 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2164 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2165 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2166 case DeclSpec::SCS_mutable: 2167 // mutable can only appear on non-static class members, so it's always 2168 // an error here 2169 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2170 D.setInvalidType(); 2171 SC = VarDecl::None; 2172 break; 2173 } 2174 2175 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2176 if (!II) { 2177 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2178 << Name.getAsString(); 2179 return 0; 2180 } 2181 2182 DiagnoseFunctionSpecifiers(D); 2183 2184 if (!DC->isRecord() && S->getFnParent() == 0) { 2185 // C99 6.9p2: The storage-class specifiers auto and register shall not 2186 // appear in the declaration specifiers in an external declaration. 2187 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2188 2189 // If this is a register variable with an asm label specified, then this 2190 // is a GNU extension. 2191 if (SC == VarDecl::Register && D.getAsmLabel()) 2192 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2193 else 2194 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2195 D.setInvalidType(); 2196 } 2197 } 2198 if (DC->isRecord() && !CurContext->isRecord()) { 2199 // This is an out-of-line definition of a static data member. 2200 if (SC == VarDecl::Static) { 2201 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2202 diag::err_static_out_of_line) 2203 << CodeModificationHint::CreateRemoval( 2204 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2205 } else if (SC == VarDecl::None) 2206 SC = VarDecl::Static; 2207 } 2208 if (SC == VarDecl::Static) { 2209 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2210 if (RD->isLocalClass()) 2211 Diag(D.getIdentifierLoc(), 2212 diag::err_static_data_member_not_allowed_in_local_class) 2213 << Name << RD->getDeclName(); 2214 } 2215 } 2216 2217 // Match up the template parameter lists with the scope specifier, then 2218 // determine whether we have a template or a template specialization. 2219 bool isExplicitSpecialization = false; 2220 if (TemplateParameterList *TemplateParams 2221 = MatchTemplateParametersToScopeSpecifier( 2222 D.getDeclSpec().getSourceRange().getBegin(), 2223 D.getCXXScopeSpec(), 2224 (TemplateParameterList**)TemplateParamLists.get(), 2225 TemplateParamLists.size(), 2226 isExplicitSpecialization)) { 2227 if (TemplateParams->size() > 0) { 2228 // There is no such thing as a variable template. 2229 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2230 << II 2231 << SourceRange(TemplateParams->getTemplateLoc(), 2232 TemplateParams->getRAngleLoc()); 2233 return 0; 2234 } else { 2235 // There is an extraneous 'template<>' for this variable. Complain 2236 // about it, but allow the declaration of the variable. 2237 Diag(TemplateParams->getTemplateLoc(), 2238 diag::err_template_variable_noparams) 2239 << II 2240 << SourceRange(TemplateParams->getTemplateLoc(), 2241 TemplateParams->getRAngleLoc()); 2242 2243 isExplicitSpecialization = true; 2244 } 2245 } 2246 2247 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2248 II, R, DInfo, SC); 2249 2250 if (D.isInvalidType()) 2251 NewVD->setInvalidDecl(); 2252 2253 if (D.getDeclSpec().isThreadSpecified()) { 2254 if (NewVD->hasLocalStorage()) 2255 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2256 else if (!Context.Target.isTLSSupported()) 2257 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2258 else 2259 NewVD->setThreadSpecified(true); 2260 } 2261 2262 // Set the lexical context. If the declarator has a C++ scope specifier, the 2263 // lexical context will be different from the semantic context. 2264 NewVD->setLexicalDeclContext(CurContext); 2265 2266 // Handle attributes prior to checking for duplicates in MergeVarDecl 2267 ProcessDeclAttributes(S, NewVD, D); 2268 2269 // Handle GNU asm-label extension (encoded as an attribute). 2270 if (Expr *E = (Expr*) D.getAsmLabel()) { 2271 // The parser guarantees this is a string. 2272 StringLiteral *SE = cast<StringLiteral>(E); 2273 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2274 SE->getByteLength()))); 2275 } 2276 2277 // If name lookup finds a previous declaration that is not in the 2278 // same scope as the new declaration, this may still be an 2279 // acceptable redeclaration. 2280 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2281 !(NewVD->hasLinkage() && 2282 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2283 PrevDecl = 0; 2284 2285 // Merge the decl with the existing one if appropriate. 2286 if (PrevDecl) { 2287 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2288 // The user tried to define a non-static data member 2289 // out-of-line (C++ [dcl.meaning]p1). 2290 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2291 << D.getCXXScopeSpec().getRange(); 2292 PrevDecl = 0; 2293 NewVD->setInvalidDecl(); 2294 } 2295 } else if (D.getCXXScopeSpec().isSet()) { 2296 // No previous declaration in the qualifying scope. 2297 Diag(D.getIdentifierLoc(), diag::err_no_member) 2298 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2299 << D.getCXXScopeSpec().getRange(); 2300 NewVD->setInvalidDecl(); 2301 } 2302 2303 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2304 2305 // This is an explicit specialization of a static data member. Check it. 2306 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2307 CheckMemberSpecialization(NewVD, PrevDecl)) 2308 NewVD->setInvalidDecl(); 2309 2310 // attributes declared post-definition are currently ignored 2311 if (PrevDecl) { 2312 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2313 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2314 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2315 Diag(Def->getLocation(), diag::note_previous_definition); 2316 } 2317 } 2318 2319 // If this is a locally-scoped extern C variable, update the map of 2320 // such variables. 2321 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2322 !NewVD->isInvalidDecl()) 2323 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2324 2325 return NewVD; 2326} 2327 2328/// \brief Perform semantic checking on a newly-created variable 2329/// declaration. 2330/// 2331/// This routine performs all of the type-checking required for a 2332/// variable declaration once it has been built. It is used both to 2333/// check variables after they have been parsed and their declarators 2334/// have been translated into a declaration, and to check variables 2335/// that have been instantiated from a template. 2336/// 2337/// Sets NewVD->isInvalidDecl() if an error was encountered. 2338void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2339 bool &Redeclaration) { 2340 // If the decl is already known invalid, don't check it. 2341 if (NewVD->isInvalidDecl()) 2342 return; 2343 2344 QualType T = NewVD->getType(); 2345 2346 if (T->isObjCInterfaceType()) { 2347 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2348 return NewVD->setInvalidDecl(); 2349 } 2350 2351 // The variable can not have an abstract class type. 2352 if (RequireNonAbstractType(NewVD->getLocation(), T, 2353 diag::err_abstract_type_in_decl, 2354 AbstractVariableType)) 2355 return NewVD->setInvalidDecl(); 2356 2357 // Emit an error if an address space was applied to decl with local storage. 2358 // This includes arrays of objects with address space qualifiers, but not 2359 // automatic variables that point to other address spaces. 2360 // ISO/IEC TR 18037 S5.1.2 2361 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2362 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2363 return NewVD->setInvalidDecl(); 2364 } 2365 2366 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2367 && !NewVD->hasAttr<BlocksAttr>()) 2368 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2369 2370 bool isVM = T->isVariablyModifiedType(); 2371 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2372 NewVD->hasAttr<BlocksAttr>()) 2373 CurFunctionNeedsScopeChecking = true; 2374 2375 if ((isVM && NewVD->hasLinkage()) || 2376 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2377 bool SizeIsNegative; 2378 QualType FixedTy = 2379 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2380 2381 if (FixedTy.isNull() && T->isVariableArrayType()) { 2382 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2383 // FIXME: This won't give the correct result for 2384 // int a[10][n]; 2385 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2386 2387 if (NewVD->isFileVarDecl()) 2388 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2389 << SizeRange; 2390 else if (NewVD->getStorageClass() == VarDecl::Static) 2391 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2392 << SizeRange; 2393 else 2394 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2395 << SizeRange; 2396 return NewVD->setInvalidDecl(); 2397 } 2398 2399 if (FixedTy.isNull()) { 2400 if (NewVD->isFileVarDecl()) 2401 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2402 else 2403 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2404 return NewVD->setInvalidDecl(); 2405 } 2406 2407 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2408 NewVD->setType(FixedTy); 2409 } 2410 2411 if (!PrevDecl && NewVD->isExternC()) { 2412 // Since we did not find anything by this name and we're declaring 2413 // an extern "C" variable, look for a non-visible extern "C" 2414 // declaration with the same name. 2415 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2416 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2417 if (Pos != LocallyScopedExternalDecls.end()) 2418 PrevDecl = Pos->second; 2419 } 2420 2421 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2422 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2423 << T; 2424 return NewVD->setInvalidDecl(); 2425 } 2426 2427 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2428 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2429 return NewVD->setInvalidDecl(); 2430 } 2431 2432 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2433 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2434 return NewVD->setInvalidDecl(); 2435 } 2436 2437 if (PrevDecl) { 2438 Redeclaration = true; 2439 MergeVarDecl(NewVD, PrevDecl); 2440 } 2441} 2442 2443static bool isUsingDecl(Decl *D) { 2444 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2445} 2446 2447/// \brief Data used with FindOverriddenMethod 2448struct FindOverriddenMethodData { 2449 Sema *S; 2450 CXXMethodDecl *Method; 2451}; 2452 2453/// \brief Member lookup function that determines whether a given C++ 2454/// method overrides a method in a base class, to be used with 2455/// CXXRecordDecl::lookupInBases(). 2456static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2457 CXXBasePath &Path, 2458 void *UserData) { 2459 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2460 2461 FindOverriddenMethodData *Data 2462 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2463 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2464 Path.Decls.first != Path.Decls.second; 2465 ++Path.Decls.first) { 2466 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2467 OverloadedFunctionDecl::function_iterator MatchedDecl; 2468 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2469 return true; 2470 } 2471 } 2472 2473 return false; 2474} 2475 2476NamedDecl* 2477Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2478 QualType R, DeclaratorInfo *DInfo, 2479 NamedDecl* PrevDecl, 2480 MultiTemplateParamsArg TemplateParamLists, 2481 bool IsFunctionDefinition, bool &Redeclaration) { 2482 assert(R.getTypePtr()->isFunctionType()); 2483 2484 DeclarationName Name = GetNameForDeclarator(D); 2485 FunctionDecl::StorageClass SC = FunctionDecl::None; 2486 switch (D.getDeclSpec().getStorageClassSpec()) { 2487 default: assert(0 && "Unknown storage class!"); 2488 case DeclSpec::SCS_auto: 2489 case DeclSpec::SCS_register: 2490 case DeclSpec::SCS_mutable: 2491 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2492 diag::err_typecheck_sclass_func); 2493 D.setInvalidType(); 2494 break; 2495 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2496 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2497 case DeclSpec::SCS_static: { 2498 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2499 // C99 6.7.1p5: 2500 // The declaration of an identifier for a function that has 2501 // block scope shall have no explicit storage-class specifier 2502 // other than extern 2503 // See also (C++ [dcl.stc]p4). 2504 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2505 diag::err_static_block_func); 2506 SC = FunctionDecl::None; 2507 } else 2508 SC = FunctionDecl::Static; 2509 break; 2510 } 2511 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2512 } 2513 2514 if (D.getDeclSpec().isThreadSpecified()) 2515 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2516 2517 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2518 bool isInline = D.getDeclSpec().isInlineSpecified(); 2519 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2520 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2521 2522 // Check that the return type is not an abstract class type. 2523 // For record types, this is done by the AbstractClassUsageDiagnoser once 2524 // the class has been completely parsed. 2525 if (!DC->isRecord() && 2526 RequireNonAbstractType(D.getIdentifierLoc(), 2527 R->getAs<FunctionType>()->getResultType(), 2528 diag::err_abstract_type_in_decl, 2529 AbstractReturnType)) 2530 D.setInvalidType(); 2531 2532 // Do not allow returning a objc interface by-value. 2533 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2534 Diag(D.getIdentifierLoc(), 2535 diag::err_object_cannot_be_passed_returned_by_value) << 0 2536 << R->getAs<FunctionType>()->getResultType(); 2537 D.setInvalidType(); 2538 } 2539 2540 bool isVirtualOkay = false; 2541 FunctionDecl *NewFD; 2542 2543 if (isFriend) { 2544 // DC is the namespace in which the function is being declared. 2545 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2546 "friend function being created in a non-namespace context"); 2547 2548 // C++ [class.friend]p5 2549 // A function can be defined in a friend declaration of a 2550 // class . . . . Such a function is implicitly inline. 2551 isInline |= IsFunctionDefinition; 2552 } 2553 2554 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2555 // This is a C++ constructor declaration. 2556 assert(DC->isRecord() && 2557 "Constructors can only be declared in a member context"); 2558 2559 R = CheckConstructorDeclarator(D, R, SC); 2560 2561 // Create the new declaration 2562 NewFD = CXXConstructorDecl::Create(Context, 2563 cast<CXXRecordDecl>(DC), 2564 D.getIdentifierLoc(), Name, R, DInfo, 2565 isExplicit, isInline, 2566 /*isImplicitlyDeclared=*/false); 2567 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2568 // This is a C++ destructor declaration. 2569 if (DC->isRecord()) { 2570 R = CheckDestructorDeclarator(D, SC); 2571 2572 NewFD = CXXDestructorDecl::Create(Context, 2573 cast<CXXRecordDecl>(DC), 2574 D.getIdentifierLoc(), Name, R, 2575 isInline, 2576 /*isImplicitlyDeclared=*/false); 2577 2578 isVirtualOkay = true; 2579 } else { 2580 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2581 2582 // Create a FunctionDecl to satisfy the function definition parsing 2583 // code path. 2584 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2585 Name, R, DInfo, SC, isInline, 2586 /*hasPrototype=*/true); 2587 D.setInvalidType(); 2588 } 2589 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2590 if (!DC->isRecord()) { 2591 Diag(D.getIdentifierLoc(), 2592 diag::err_conv_function_not_member); 2593 return 0; 2594 } 2595 2596 CheckConversionDeclarator(D, R, SC); 2597 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2598 D.getIdentifierLoc(), Name, R, DInfo, 2599 isInline, isExplicit); 2600 2601 isVirtualOkay = true; 2602 } else if (DC->isRecord()) { 2603 // If the of the function is the same as the name of the record, then this 2604 // must be an invalid constructor that has a return type. 2605 // (The parser checks for a return type and makes the declarator a 2606 // constructor if it has no return type). 2607 // must have an invalid constructor that has a return type 2608 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2609 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2610 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2611 << SourceRange(D.getIdentifierLoc()); 2612 return 0; 2613 } 2614 2615 // This is a C++ method declaration. 2616 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2617 D.getIdentifierLoc(), Name, R, DInfo, 2618 (SC == FunctionDecl::Static), isInline); 2619 2620 isVirtualOkay = (SC != FunctionDecl::Static); 2621 } else { 2622 // Determine whether the function was written with a 2623 // prototype. This true when: 2624 // - we're in C++ (where every function has a prototype), 2625 // - there is a prototype in the declarator, or 2626 // - the type R of the function is some kind of typedef or other reference 2627 // to a type name (which eventually refers to a function type). 2628 bool HasPrototype = 2629 getLangOptions().CPlusPlus || 2630 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2631 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2632 2633 NewFD = FunctionDecl::Create(Context, DC, 2634 D.getIdentifierLoc(), 2635 Name, R, DInfo, SC, isInline, HasPrototype); 2636 } 2637 2638 if (D.isInvalidType()) 2639 NewFD->setInvalidDecl(); 2640 2641 // Set the lexical context. If the declarator has a C++ 2642 // scope specifier, or is the object of a friend declaration, the 2643 // lexical context will be different from the semantic context. 2644 NewFD->setLexicalDeclContext(CurContext); 2645 2646 // Match up the template parameter lists with the scope specifier, then 2647 // determine whether we have a template or a template specialization. 2648 FunctionTemplateDecl *FunctionTemplate = 0; 2649 bool isExplicitSpecialization = false; 2650 bool isFunctionTemplateSpecialization = false; 2651 if (TemplateParameterList *TemplateParams 2652 = MatchTemplateParametersToScopeSpecifier( 2653 D.getDeclSpec().getSourceRange().getBegin(), 2654 D.getCXXScopeSpec(), 2655 (TemplateParameterList**)TemplateParamLists.get(), 2656 TemplateParamLists.size(), 2657 isExplicitSpecialization)) { 2658 if (TemplateParams->size() > 0) { 2659 // This is a function template 2660 2661 // Check that we can declare a template here. 2662 if (CheckTemplateDeclScope(S, TemplateParams)) 2663 return 0; 2664 2665 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2666 NewFD->getLocation(), 2667 Name, TemplateParams, 2668 NewFD); 2669 FunctionTemplate->setLexicalDeclContext(CurContext); 2670 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2671 } else { 2672 // This is a function template specialization. 2673 isFunctionTemplateSpecialization = true; 2674 } 2675 2676 // FIXME: Free this memory properly. 2677 TemplateParamLists.release(); 2678 } 2679 2680 // C++ [dcl.fct.spec]p5: 2681 // The virtual specifier shall only be used in declarations of 2682 // nonstatic class member functions that appear within a 2683 // member-specification of a class declaration; see 10.3. 2684 // 2685 if (isVirtual && !NewFD->isInvalidDecl()) { 2686 if (!isVirtualOkay) { 2687 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2688 diag::err_virtual_non_function); 2689 } else if (!CurContext->isRecord()) { 2690 // 'virtual' was specified outside of the class. 2691 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2692 << CodeModificationHint::CreateRemoval( 2693 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2694 } else { 2695 // Okay: Add virtual to the method. 2696 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2697 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2698 CurClass->setAggregate(false); 2699 CurClass->setPOD(false); 2700 CurClass->setEmpty(false); 2701 CurClass->setPolymorphic(true); 2702 CurClass->setHasTrivialConstructor(false); 2703 CurClass->setHasTrivialCopyConstructor(false); 2704 CurClass->setHasTrivialCopyAssignment(false); 2705 } 2706 } 2707 2708 if (isFriend) { 2709 if (FunctionTemplate) { 2710 FunctionTemplate->setObjectOfFriendDecl( 2711 /* PreviouslyDeclared= */ PrevDecl != NULL); 2712 FunctionTemplate->setAccess(AS_public); 2713 } 2714 else 2715 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2716 2717 NewFD->setAccess(AS_public); 2718 } 2719 2720 2721 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2722 // Look for virtual methods in base classes that this method might override. 2723 CXXBasePaths Paths; 2724 FindOverriddenMethodData Data; 2725 Data.Method = NewMD; 2726 Data.S = this; 2727 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2728 Paths)) { 2729 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2730 E = Paths.found_decls_end(); I != E; ++I) { 2731 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2732 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2733 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2734 NewMD->addOverriddenMethod(OldMD); 2735 } 2736 } 2737 } 2738 } 2739 2740 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2741 !CurContext->isRecord()) { 2742 // C++ [class.static]p1: 2743 // A data or function member of a class may be declared static 2744 // in a class definition, in which case it is a static member of 2745 // the class. 2746 2747 // Complain about the 'static' specifier if it's on an out-of-line 2748 // member function definition. 2749 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2750 diag::err_static_out_of_line) 2751 << CodeModificationHint::CreateRemoval( 2752 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2753 } 2754 2755 // Handle GNU asm-label extension (encoded as an attribute). 2756 if (Expr *E = (Expr*) D.getAsmLabel()) { 2757 // The parser guarantees this is a string. 2758 StringLiteral *SE = cast<StringLiteral>(E); 2759 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2760 SE->getByteLength()))); 2761 } 2762 2763 // Copy the parameter declarations from the declarator D to the function 2764 // declaration NewFD, if they are available. First scavenge them into Params. 2765 llvm::SmallVector<ParmVarDecl*, 16> Params; 2766 if (D.getNumTypeObjects() > 0) { 2767 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2768 2769 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2770 // function that takes no arguments, not a function that takes a 2771 // single void argument. 2772 // We let through "const void" here because Sema::GetTypeForDeclarator 2773 // already checks for that case. 2774 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2775 FTI.ArgInfo[0].Param && 2776 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2777 // Empty arg list, don't push any params. 2778 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2779 2780 // In C++, the empty parameter-type-list must be spelled "void"; a 2781 // typedef of void is not permitted. 2782 if (getLangOptions().CPlusPlus && 2783 Param->getType().getUnqualifiedType() != Context.VoidTy) 2784 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2785 // FIXME: Leaks decl? 2786 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2787 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2788 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2789 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2790 Param->setDeclContext(NewFD); 2791 Params.push_back(Param); 2792 } 2793 } 2794 2795 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2796 // When we're declaring a function with a typedef, typeof, etc as in the 2797 // following example, we'll need to synthesize (unnamed) 2798 // parameters for use in the declaration. 2799 // 2800 // @code 2801 // typedef void fn(int); 2802 // fn f; 2803 // @endcode 2804 2805 // Synthesize a parameter for each argument type. 2806 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2807 AE = FT->arg_type_end(); AI != AE; ++AI) { 2808 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2809 SourceLocation(), 0, 2810 *AI, /*DInfo=*/0, 2811 VarDecl::None, 0); 2812 Param->setImplicit(); 2813 Params.push_back(Param); 2814 } 2815 } else { 2816 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2817 "Should not need args for typedef of non-prototype fn"); 2818 } 2819 // Finally, we know we have the right number of parameters, install them. 2820 NewFD->setParams(Context, Params.data(), Params.size()); 2821 2822 // If name lookup finds a previous declaration that is not in the 2823 // same scope as the new declaration, this may still be an 2824 // acceptable redeclaration. 2825 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2826 !(NewFD->hasLinkage() && 2827 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2828 PrevDecl = 0; 2829 2830 // If the declarator is a template-id, translate the parser's template 2831 // argument list into our AST format. 2832 bool HasExplicitTemplateArgs = false; 2833 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 2834 SourceLocation LAngleLoc, RAngleLoc; 2835 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2836 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2837 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2838 TemplateId->getTemplateArgs(), 2839 TemplateId->NumArgs); 2840 translateTemplateArguments(TemplateArgsPtr, 2841 TemplateArgs); 2842 TemplateArgsPtr.release(); 2843 2844 HasExplicitTemplateArgs = true; 2845 LAngleLoc = TemplateId->LAngleLoc; 2846 RAngleLoc = TemplateId->RAngleLoc; 2847 2848 if (FunctionTemplate) { 2849 // FIXME: Diagnose function template with explicit template 2850 // arguments. 2851 HasExplicitTemplateArgs = false; 2852 } else if (!isFunctionTemplateSpecialization && 2853 !D.getDeclSpec().isFriendSpecified()) { 2854 // We have encountered something that the user meant to be a 2855 // specialization (because it has explicitly-specified template 2856 // arguments) but that was not introduced with a "template<>" (or had 2857 // too few of them). 2858 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2859 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2860 << CodeModificationHint::CreateInsertion( 2861 D.getDeclSpec().getSourceRange().getBegin(), 2862 "template<> "); 2863 isFunctionTemplateSpecialization = true; 2864 } 2865 } 2866 2867 if (isFunctionTemplateSpecialization) { 2868 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2869 LAngleLoc, TemplateArgs.data(), 2870 TemplateArgs.size(), RAngleLoc, 2871 PrevDecl)) 2872 NewFD->setInvalidDecl(); 2873 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2874 CheckMemberSpecialization(NewFD, PrevDecl)) 2875 NewFD->setInvalidDecl(); 2876 2877 // Perform semantic checking on the function declaration. 2878 bool OverloadableAttrRequired = false; // FIXME: HACK! 2879 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2880 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2881 2882 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2883 // An out-of-line member function declaration must also be a 2884 // definition (C++ [dcl.meaning]p1). 2885 // Note that this is not the case for explicit specializations of 2886 // function templates or member functions of class templates, per 2887 // C++ [temp.expl.spec]p2. 2888 if (!IsFunctionDefinition && !isFriend && 2889 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2890 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2891 << D.getCXXScopeSpec().getRange(); 2892 NewFD->setInvalidDecl(); 2893 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2894 // The user tried to provide an out-of-line definition for a 2895 // function that is a member of a class or namespace, but there 2896 // was no such member function declared (C++ [class.mfct]p2, 2897 // C++ [namespace.memdef]p2). For example: 2898 // 2899 // class X { 2900 // void f() const; 2901 // }; 2902 // 2903 // void X::f() { } // ill-formed 2904 // 2905 // Complain about this problem, and attempt to suggest close 2906 // matches (e.g., those that differ only in cv-qualifiers and 2907 // whether the parameter types are references). 2908 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2909 << Name << DC << D.getCXXScopeSpec().getRange(); 2910 NewFD->setInvalidDecl(); 2911 2912 LookupResult Prev; 2913 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2914 assert(!Prev.isAmbiguous() && 2915 "Cannot have an ambiguity in previous-declaration lookup"); 2916 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2917 Func != FuncEnd; ++Func) { 2918 if (isa<FunctionDecl>(*Func) && 2919 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2920 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2921 } 2922 2923 PrevDecl = 0; 2924 } 2925 } 2926 2927 // Handle attributes. We need to have merged decls when handling attributes 2928 // (for example to check for conflicts, etc). 2929 // FIXME: This needs to happen before we merge declarations. Then, 2930 // let attribute merging cope with attribute conflicts. 2931 ProcessDeclAttributes(S, NewFD, D); 2932 2933 // attributes declared post-definition are currently ignored 2934 if (Redeclaration && PrevDecl) { 2935 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2936 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2937 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2938 Diag(Def->getLocation(), diag::note_previous_definition); 2939 } 2940 } 2941 2942 AddKnownFunctionAttributes(NewFD); 2943 2944 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2945 // If a function name is overloadable in C, then every function 2946 // with that name must be marked "overloadable". 2947 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2948 << Redeclaration << NewFD; 2949 if (PrevDecl) 2950 Diag(PrevDecl->getLocation(), 2951 diag::note_attribute_overloadable_prev_overload); 2952 NewFD->addAttr(::new (Context) OverloadableAttr()); 2953 } 2954 2955 // If this is a locally-scoped extern C function, update the 2956 // map of such names. 2957 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2958 && !NewFD->isInvalidDecl()) 2959 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2960 2961 // Set this FunctionDecl's range up to the right paren. 2962 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2963 2964 if (FunctionTemplate && NewFD->isInvalidDecl()) 2965 FunctionTemplate->setInvalidDecl(); 2966 2967 if (FunctionTemplate) 2968 return FunctionTemplate; 2969 2970 return NewFD; 2971} 2972 2973/// \brief Perform semantic checking of a new function declaration. 2974/// 2975/// Performs semantic analysis of the new function declaration 2976/// NewFD. This routine performs all semantic checking that does not 2977/// require the actual declarator involved in the declaration, and is 2978/// used both for the declaration of functions as they are parsed 2979/// (called via ActOnDeclarator) and for the declaration of functions 2980/// that have been instantiated via C++ template instantiation (called 2981/// via InstantiateDecl). 2982/// 2983/// \param IsExplicitSpecialiation whether this new function declaration is 2984/// an explicit specialization of the previous declaration. 2985/// 2986/// This sets NewFD->isInvalidDecl() to true if there was an error. 2987void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2988 bool IsExplicitSpecialization, 2989 bool &Redeclaration, 2990 bool &OverloadableAttrRequired) { 2991 // If NewFD is already known erroneous, don't do any of this checking. 2992 if (NewFD->isInvalidDecl()) 2993 return; 2994 2995 if (NewFD->getResultType()->isVariablyModifiedType()) { 2996 // Functions returning a variably modified type violate C99 6.7.5.2p2 2997 // because all functions have linkage. 2998 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2999 return NewFD->setInvalidDecl(); 3000 } 3001 3002 if (NewFD->isMain()) 3003 CheckMain(NewFD); 3004 3005 // Check for a previous declaration of this name. 3006 if (!PrevDecl && NewFD->isExternC()) { 3007 // Since we did not find anything by this name and we're declaring 3008 // an extern "C" function, look for a non-visible extern "C" 3009 // declaration with the same name. 3010 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3011 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3012 if (Pos != LocallyScopedExternalDecls.end()) 3013 PrevDecl = Pos->second; 3014 } 3015 3016 // Merge or overload the declaration with an existing declaration of 3017 // the same name, if appropriate. 3018 if (PrevDecl) { 3019 // Determine whether NewFD is an overload of PrevDecl or 3020 // a declaration that requires merging. If it's an overload, 3021 // there's no more work to do here; we'll just add the new 3022 // function to the scope. 3023 OverloadedFunctionDecl::function_iterator MatchedDecl; 3024 3025 if (!getLangOptions().CPlusPlus && 3026 AllowOverloadingOfFunction(PrevDecl, Context)) { 3027 OverloadableAttrRequired = true; 3028 3029 // Functions marked "overloadable" must have a prototype (that 3030 // we can't get through declaration merging). 3031 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3032 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3033 << NewFD; 3034 Redeclaration = true; 3035 3036 // Turn this into a variadic function with no parameters. 3037 QualType R = Context.getFunctionType( 3038 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3039 0, 0, true, 0); 3040 NewFD->setType(R); 3041 return NewFD->setInvalidDecl(); 3042 } 3043 } 3044 3045 if (PrevDecl && 3046 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3047 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3048 Redeclaration = true; 3049 Decl *OldDecl = PrevDecl; 3050 3051 // If PrevDecl was an overloaded function, extract the 3052 // FunctionDecl that matched. 3053 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3054 OldDecl = *MatchedDecl; 3055 3056 // NewFD and OldDecl represent declarations that need to be 3057 // merged. 3058 if (MergeFunctionDecl(NewFD, OldDecl)) 3059 return NewFD->setInvalidDecl(); 3060 3061 if (FunctionTemplateDecl *OldTemplateDecl 3062 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3063 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3064 FunctionTemplateDecl *NewTemplateDecl 3065 = NewFD->getDescribedFunctionTemplate(); 3066 assert(NewTemplateDecl && "Template/non-template mismatch"); 3067 if (CXXMethodDecl *Method 3068 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3069 Method->setAccess(OldTemplateDecl->getAccess()); 3070 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3071 } 3072 3073 // If this is an explicit specialization of a member that is a function 3074 // template, mark it as a member specialization. 3075 if (IsExplicitSpecialization && 3076 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3077 NewTemplateDecl->setMemberSpecialization(); 3078 assert(OldTemplateDecl->isMemberSpecialization()); 3079 } 3080 } else { 3081 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3082 NewFD->setAccess(OldDecl->getAccess()); 3083 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3084 } 3085 } 3086 } 3087 3088 // Semantic checking for this function declaration (in isolation). 3089 if (getLangOptions().CPlusPlus) { 3090 // C++-specific checks. 3091 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3092 CheckConstructor(Constructor); 3093 } else if (isa<CXXDestructorDecl>(NewFD)) { 3094 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3095 QualType ClassType = Context.getTypeDeclType(Record); 3096 if (!ClassType->isDependentType()) { 3097 DeclarationName Name 3098 = Context.DeclarationNames.getCXXDestructorName( 3099 Context.getCanonicalType(ClassType)); 3100 if (NewFD->getDeclName() != Name) { 3101 Diag(NewFD->getLocation(), diag::err_destructor_name); 3102 return NewFD->setInvalidDecl(); 3103 } 3104 } 3105 Record->setUserDeclaredDestructor(true); 3106 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3107 // user-defined destructor. 3108 Record->setPOD(false); 3109 3110 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3111 // declared destructor. 3112 // FIXME: C++0x: don't do this for "= default" destructors 3113 Record->setHasTrivialDestructor(false); 3114 } else if (CXXConversionDecl *Conversion 3115 = dyn_cast<CXXConversionDecl>(NewFD)) 3116 ActOnConversionDeclarator(Conversion); 3117 3118 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3119 if (NewFD->isOverloadedOperator() && 3120 CheckOverloadedOperatorDeclaration(NewFD)) 3121 return NewFD->setInvalidDecl(); 3122 3123 // In C++, check default arguments now that we have merged decls. Unless 3124 // the lexical context is the class, because in this case this is done 3125 // during delayed parsing anyway. 3126 if (!CurContext->isRecord()) 3127 CheckCXXDefaultArguments(NewFD); 3128 } 3129} 3130 3131void Sema::CheckMain(FunctionDecl* FD) { 3132 // C++ [basic.start.main]p3: A program that declares main to be inline 3133 // or static is ill-formed. 3134 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3135 // shall not appear in a declaration of main. 3136 // static main is not an error under C99, but we should warn about it. 3137 bool isInline = FD->isInlineSpecified(); 3138 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3139 if (isInline || isStatic) { 3140 unsigned diagID = diag::warn_unusual_main_decl; 3141 if (isInline || getLangOptions().CPlusPlus) 3142 diagID = diag::err_unusual_main_decl; 3143 3144 int which = isStatic + (isInline << 1) - 1; 3145 Diag(FD->getLocation(), diagID) << which; 3146 } 3147 3148 QualType T = FD->getType(); 3149 assert(T->isFunctionType() && "function decl is not of function type"); 3150 const FunctionType* FT = T->getAs<FunctionType>(); 3151 3152 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3153 // TODO: add a replacement fixit to turn the return type into 'int'. 3154 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3155 FD->setInvalidDecl(true); 3156 } 3157 3158 // Treat protoless main() as nullary. 3159 if (isa<FunctionNoProtoType>(FT)) return; 3160 3161 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3162 unsigned nparams = FTP->getNumArgs(); 3163 assert(FD->getNumParams() == nparams); 3164 3165 if (nparams > 3) { 3166 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3167 FD->setInvalidDecl(true); 3168 nparams = 3; 3169 } 3170 3171 // FIXME: a lot of the following diagnostics would be improved 3172 // if we had some location information about types. 3173 3174 QualType CharPP = 3175 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3176 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3177 3178 for (unsigned i = 0; i < nparams; ++i) { 3179 QualType AT = FTP->getArgType(i); 3180 3181 bool mismatch = true; 3182 3183 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3184 mismatch = false; 3185 else if (Expected[i] == CharPP) { 3186 // As an extension, the following forms are okay: 3187 // char const ** 3188 // char const * const * 3189 // char * const * 3190 3191 QualifierCollector qs; 3192 const PointerType* PT; 3193 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3194 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3195 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3196 qs.removeConst(); 3197 mismatch = !qs.empty(); 3198 } 3199 } 3200 3201 if (mismatch) { 3202 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3203 // TODO: suggest replacing given type with expected type 3204 FD->setInvalidDecl(true); 3205 } 3206 } 3207 3208 if (nparams == 1 && !FD->isInvalidDecl()) { 3209 Diag(FD->getLocation(), diag::warn_main_one_arg); 3210 } 3211} 3212 3213bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3214 // FIXME: Need strict checking. In C89, we need to check for 3215 // any assignment, increment, decrement, function-calls, or 3216 // commas outside of a sizeof. In C99, it's the same list, 3217 // except that the aforementioned are allowed in unevaluated 3218 // expressions. Everything else falls under the 3219 // "may accept other forms of constant expressions" exception. 3220 // (We never end up here for C++, so the constant expression 3221 // rules there don't matter.) 3222 if (Init->isConstantInitializer(Context)) 3223 return false; 3224 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3225 << Init->getSourceRange(); 3226 return true; 3227} 3228 3229void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3230 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3231} 3232 3233/// AddInitializerToDecl - Adds the initializer Init to the 3234/// declaration dcl. If DirectInit is true, this is C++ direct 3235/// initialization rather than copy initialization. 3236void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3237 Decl *RealDecl = dcl.getAs<Decl>(); 3238 // If there is no declaration, there was an error parsing it. Just ignore 3239 // the initializer. 3240 if (RealDecl == 0) 3241 return; 3242 3243 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3244 // With declarators parsed the way they are, the parser cannot 3245 // distinguish between a normal initializer and a pure-specifier. 3246 // Thus this grotesque test. 3247 IntegerLiteral *IL; 3248 Expr *Init = static_cast<Expr *>(init.get()); 3249 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3250 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3251 if (Method->isVirtualAsWritten()) { 3252 Method->setPure(); 3253 3254 // A class is abstract if at least one function is pure virtual. 3255 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3256 } else if (!Method->isInvalidDecl()) { 3257 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3258 << Method->getDeclName() << Init->getSourceRange(); 3259 Method->setInvalidDecl(); 3260 } 3261 } else { 3262 Diag(Method->getLocation(), diag::err_member_function_initialization) 3263 << Method->getDeclName() << Init->getSourceRange(); 3264 Method->setInvalidDecl(); 3265 } 3266 return; 3267 } 3268 3269 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3270 if (!VDecl) { 3271 if (getLangOptions().CPlusPlus && 3272 RealDecl->getLexicalDeclContext()->isRecord() && 3273 isa<NamedDecl>(RealDecl)) 3274 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3275 << cast<NamedDecl>(RealDecl)->getDeclName(); 3276 else 3277 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3278 RealDecl->setInvalidDecl(); 3279 return; 3280 } 3281 3282 if (!VDecl->getType()->isArrayType() && 3283 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3284 diag::err_typecheck_decl_incomplete_type)) { 3285 RealDecl->setInvalidDecl(); 3286 return; 3287 } 3288 3289 const VarDecl *Def = 0; 3290 if (VDecl->getDefinition(Def)) { 3291 Diag(VDecl->getLocation(), diag::err_redefinition) 3292 << VDecl->getDeclName(); 3293 Diag(Def->getLocation(), diag::note_previous_definition); 3294 VDecl->setInvalidDecl(); 3295 return; 3296 } 3297 3298 // Take ownership of the expression, now that we're sure we have somewhere 3299 // to put it. 3300 Expr *Init = init.takeAs<Expr>(); 3301 assert(Init && "missing initializer"); 3302 3303 // Get the decls type and save a reference for later, since 3304 // CheckInitializerTypes may change it. 3305 QualType DclT = VDecl->getType(), SavT = DclT; 3306 if (VDecl->isBlockVarDecl()) { 3307 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3308 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3309 VDecl->setInvalidDecl(); 3310 } else if (!VDecl->isInvalidDecl()) { 3311 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3312 VDecl->getDeclName(), DirectInit)) 3313 VDecl->setInvalidDecl(); 3314 3315 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3316 // Don't check invalid declarations to avoid emitting useless diagnostics. 3317 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3318 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3319 CheckForConstantInitializer(Init, DclT); 3320 } 3321 } 3322 } else if (VDecl->isStaticDataMember() && 3323 VDecl->getLexicalDeclContext()->isRecord()) { 3324 // This is an in-class initialization for a static data member, e.g., 3325 // 3326 // struct S { 3327 // static const int value = 17; 3328 // }; 3329 3330 // Attach the initializer 3331 VDecl->setInit(Context, Init); 3332 3333 // C++ [class.mem]p4: 3334 // A member-declarator can contain a constant-initializer only 3335 // if it declares a static member (9.4) of const integral or 3336 // const enumeration type, see 9.4.2. 3337 QualType T = VDecl->getType(); 3338 if (!T->isDependentType() && 3339 (!Context.getCanonicalType(T).isConstQualified() || 3340 !T->isIntegralType())) { 3341 Diag(VDecl->getLocation(), diag::err_member_initialization) 3342 << VDecl->getDeclName() << Init->getSourceRange(); 3343 VDecl->setInvalidDecl(); 3344 } else { 3345 // C++ [class.static.data]p4: 3346 // If a static data member is of const integral or const 3347 // enumeration type, its declaration in the class definition 3348 // can specify a constant-initializer which shall be an 3349 // integral constant expression (5.19). 3350 if (!Init->isTypeDependent() && 3351 !Init->getType()->isIntegralType()) { 3352 // We have a non-dependent, non-integral or enumeration type. 3353 Diag(Init->getSourceRange().getBegin(), 3354 diag::err_in_class_initializer_non_integral_type) 3355 << Init->getType() << Init->getSourceRange(); 3356 VDecl->setInvalidDecl(); 3357 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3358 // Check whether the expression is a constant expression. 3359 llvm::APSInt Value; 3360 SourceLocation Loc; 3361 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3362 Diag(Loc, diag::err_in_class_initializer_non_constant) 3363 << Init->getSourceRange(); 3364 VDecl->setInvalidDecl(); 3365 } else if (!VDecl->getType()->isDependentType()) 3366 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3367 } 3368 } 3369 } else if (VDecl->isFileVarDecl()) { 3370 if (VDecl->getStorageClass() == VarDecl::Extern) 3371 Diag(VDecl->getLocation(), diag::warn_extern_init); 3372 if (!VDecl->isInvalidDecl()) 3373 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3374 VDecl->getDeclName(), DirectInit)) 3375 VDecl->setInvalidDecl(); 3376 3377 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3378 // Don't check invalid declarations to avoid emitting useless diagnostics. 3379 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3380 // C99 6.7.8p4. All file scoped initializers need to be constant. 3381 CheckForConstantInitializer(Init, DclT); 3382 } 3383 } 3384 // If the type changed, it means we had an incomplete type that was 3385 // completed by the initializer. For example: 3386 // int ary[] = { 1, 3, 5 }; 3387 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3388 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3389 VDecl->setType(DclT); 3390 Init->setType(DclT); 3391 } 3392 3393 Init = MaybeCreateCXXExprWithTemporaries(Init, 3394 /*ShouldDestroyTemporaries=*/true); 3395 // Attach the initializer to the decl. 3396 VDecl->setInit(Context, Init); 3397 3398 // If the previous declaration of VDecl was a tentative definition, 3399 // remove it from the set of tentative definitions. 3400 if (VDecl->getPreviousDeclaration() && 3401 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3402 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3403 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3404 } 3405 3406 return; 3407} 3408 3409void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3410 bool TypeContainsUndeducedAuto) { 3411 Decl *RealDecl = dcl.getAs<Decl>(); 3412 3413 // If there is no declaration, there was an error parsing it. Just ignore it. 3414 if (RealDecl == 0) 3415 return; 3416 3417 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3418 QualType Type = Var->getType(); 3419 3420 // Record tentative definitions. 3421 if (Var->isTentativeDefinition(Context)) { 3422 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3423 InsertPair = 3424 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3425 3426 // Keep the latest definition in the map. If we see 'int i; int i;' we 3427 // want the second one in the map. 3428 InsertPair.first->second = Var; 3429 3430 // However, for the list, we don't care about the order, just make sure 3431 // that there are no dupes for a given declaration name. 3432 if (InsertPair.second) 3433 TentativeDefinitionList.push_back(Var->getDeclName()); 3434 } 3435 3436 // C++ [dcl.init.ref]p3: 3437 // The initializer can be omitted for a reference only in a 3438 // parameter declaration (8.3.5), in the declaration of a 3439 // function return type, in the declaration of a class member 3440 // within its class declaration (9.2), and where the extern 3441 // specifier is explicitly used. 3442 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3443 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3444 << Var->getDeclName() 3445 << SourceRange(Var->getLocation(), Var->getLocation()); 3446 Var->setInvalidDecl(); 3447 return; 3448 } 3449 3450 // C++0x [dcl.spec.auto]p3 3451 if (TypeContainsUndeducedAuto) { 3452 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3453 << Var->getDeclName() << Type; 3454 Var->setInvalidDecl(); 3455 return; 3456 } 3457 3458 // An array without size is an incomplete type, and there are no special 3459 // rules in C++ to make such a definition acceptable. 3460 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3461 !Var->hasExternalStorage()) { 3462 Diag(Var->getLocation(), 3463 diag::err_typecheck_incomplete_array_needs_initializer); 3464 Var->setInvalidDecl(); 3465 return; 3466 } 3467 3468 // C++ [temp.expl.spec]p15: 3469 // An explicit specialization of a static data member of a template is a 3470 // definition if the declaration includes an initializer; otherwise, it 3471 // is a declaration. 3472 if (Var->isStaticDataMember() && 3473 Var->getInstantiatedFromStaticDataMember() && 3474 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3475 return; 3476 3477 // C++ [dcl.init]p9: 3478 // If no initializer is specified for an object, and the object 3479 // is of (possibly cv-qualified) non-POD class type (or array 3480 // thereof), the object shall be default-initialized; if the 3481 // object is of const-qualified type, the underlying class type 3482 // shall have a user-declared default constructor. 3483 // 3484 // FIXME: Diagnose the "user-declared default constructor" bit. 3485 if (getLangOptions().CPlusPlus) { 3486 QualType InitType = Type; 3487 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3488 InitType = Context.getBaseElementType(Array); 3489 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3490 InitType->isRecordType() && !InitType->isDependentType()) { 3491 if (!RequireCompleteType(Var->getLocation(), InitType, 3492 diag::err_invalid_incomplete_type_use)) { 3493 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3494 3495 CXXConstructorDecl *Constructor 3496 = PerformInitializationByConstructor(InitType, 3497 MultiExprArg(*this, 0, 0), 3498 Var->getLocation(), 3499 SourceRange(Var->getLocation(), 3500 Var->getLocation()), 3501 Var->getDeclName(), 3502 IK_Default, 3503 ConstructorArgs); 3504 3505 // FIXME: Location info for the variable initialization? 3506 if (!Constructor) 3507 Var->setInvalidDecl(); 3508 else { 3509 // FIXME: Cope with initialization of arrays 3510 if (!Constructor->isTrivial() && 3511 InitializeVarWithConstructor(Var, Constructor, 3512 move_arg(ConstructorArgs))) 3513 Var->setInvalidDecl(); 3514 3515 FinalizeVarWithDestructor(Var, InitType); 3516 } 3517 } else { 3518 Var->setInvalidDecl(); 3519 } 3520 } 3521 } 3522 3523#if 0 3524 // FIXME: Temporarily disabled because we are not properly parsing 3525 // linkage specifications on declarations, e.g., 3526 // 3527 // extern "C" const CGPoint CGPointerZero; 3528 // 3529 // C++ [dcl.init]p9: 3530 // 3531 // If no initializer is specified for an object, and the 3532 // object is of (possibly cv-qualified) non-POD class type (or 3533 // array thereof), the object shall be default-initialized; if 3534 // the object is of const-qualified type, the underlying class 3535 // type shall have a user-declared default 3536 // constructor. Otherwise, if no initializer is specified for 3537 // an object, the object and its subobjects, if any, have an 3538 // indeterminate initial value; if the object or any of its 3539 // subobjects are of const-qualified type, the program is 3540 // ill-formed. 3541 // 3542 // This isn't technically an error in C, so we don't diagnose it. 3543 // 3544 // FIXME: Actually perform the POD/user-defined default 3545 // constructor check. 3546 if (getLangOptions().CPlusPlus && 3547 Context.getCanonicalType(Type).isConstQualified() && 3548 !Var->hasExternalStorage()) 3549 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3550 << Var->getName() 3551 << SourceRange(Var->getLocation(), Var->getLocation()); 3552#endif 3553 } 3554} 3555 3556Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3557 DeclPtrTy *Group, 3558 unsigned NumDecls) { 3559 llvm::SmallVector<Decl*, 8> Decls; 3560 3561 if (DS.isTypeSpecOwned()) 3562 Decls.push_back((Decl*)DS.getTypeRep()); 3563 3564 for (unsigned i = 0; i != NumDecls; ++i) 3565 if (Decl *D = Group[i].getAs<Decl>()) 3566 Decls.push_back(D); 3567 3568 // Perform semantic analysis that depends on having fully processed both 3569 // the declarator and initializer. 3570 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3571 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3572 if (!IDecl) 3573 continue; 3574 QualType T = IDecl->getType(); 3575 3576 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3577 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3578 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3579 if (T->isDependentType()) { 3580 // If T is dependent, we should not require a complete type. 3581 // (RequireCompleteType shouldn't be called with dependent types.) 3582 // But we still can at least check if we've got an array of unspecified 3583 // size without an initializer. 3584 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3585 !IDecl->getInit()) { 3586 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3587 << T; 3588 IDecl->setInvalidDecl(); 3589 } 3590 } else if (!IDecl->isInvalidDecl()) { 3591 // If T is an incomplete array type with an initializer list that is 3592 // dependent on something, its size has not been fixed. We could attempt 3593 // to fix the size for such arrays, but we would still have to check 3594 // here for initializers containing a C++0x vararg expansion, e.g. 3595 // template <typename... Args> void f(Args... args) { 3596 // int vals[] = { args }; 3597 // } 3598 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3599 Expr *Init = IDecl->getInit(); 3600 if (IAT && Init && 3601 (Init->isTypeDependent() || Init->isValueDependent())) { 3602 // Check that the member type of the array is complete, at least. 3603 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3604 diag::err_typecheck_decl_incomplete_type)) 3605 IDecl->setInvalidDecl(); 3606 } else if (RequireCompleteType(IDecl->getLocation(), T, 3607 diag::err_typecheck_decl_incomplete_type)) 3608 IDecl->setInvalidDecl(); 3609 } 3610 } 3611 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3612 // object that has file scope without an initializer, and without a 3613 // storage-class specifier or with the storage-class specifier "static", 3614 // constitutes a tentative definition. Note: A tentative definition with 3615 // external linkage is valid (C99 6.2.2p5). 3616 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3617 if (const IncompleteArrayType *ArrayT 3618 = Context.getAsIncompleteArrayType(T)) { 3619 if (RequireCompleteType(IDecl->getLocation(), 3620 ArrayT->getElementType(), 3621 diag::err_illegal_decl_array_incomplete_type)) 3622 IDecl->setInvalidDecl(); 3623 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3624 // C99 6.9.2p3: If the declaration of an identifier for an object is 3625 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3626 // declared type shall not be an incomplete type. 3627 // NOTE: code such as the following 3628 // static struct s; 3629 // struct s { int a; }; 3630 // is accepted by gcc. Hence here we issue a warning instead of 3631 // an error and we do not invalidate the static declaration. 3632 // NOTE: to avoid multiple warnings, only check the first declaration. 3633 if (IDecl->getPreviousDeclaration() == 0) 3634 RequireCompleteType(IDecl->getLocation(), T, 3635 diag::ext_typecheck_decl_incomplete_type); 3636 } 3637 } 3638 } 3639 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3640 Decls.data(), Decls.size())); 3641} 3642 3643 3644/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3645/// to introduce parameters into function prototype scope. 3646Sema::DeclPtrTy 3647Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3648 const DeclSpec &DS = D.getDeclSpec(); 3649 3650 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3651 VarDecl::StorageClass StorageClass = VarDecl::None; 3652 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3653 StorageClass = VarDecl::Register; 3654 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3655 Diag(DS.getStorageClassSpecLoc(), 3656 diag::err_invalid_storage_class_in_func_decl); 3657 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3658 } 3659 3660 if (D.getDeclSpec().isThreadSpecified()) 3661 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3662 3663 DiagnoseFunctionSpecifiers(D); 3664 3665 // Check that there are no default arguments inside the type of this 3666 // parameter (C++ only). 3667 if (getLangOptions().CPlusPlus) 3668 CheckExtraCXXDefaultArguments(D); 3669 3670 DeclaratorInfo *DInfo = 0; 3671 TagDecl *OwnedDecl = 0; 3672 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3673 3674 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3675 // C++ [dcl.fct]p6: 3676 // Types shall not be defined in return or parameter types. 3677 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3678 << Context.getTypeDeclType(OwnedDecl); 3679 } 3680 3681 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3682 // Can this happen for params? We already checked that they don't conflict 3683 // among each other. Here they can only shadow globals, which is ok. 3684 IdentifierInfo *II = D.getIdentifier(); 3685 if (II) { 3686 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3687 if (PrevDecl->isTemplateParameter()) { 3688 // Maybe we will complain about the shadowed template parameter. 3689 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3690 // Just pretend that we didn't see the previous declaration. 3691 PrevDecl = 0; 3692 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3693 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3694 3695 // Recover by removing the name 3696 II = 0; 3697 D.SetIdentifier(0, D.getIdentifierLoc()); 3698 } 3699 } 3700 } 3701 3702 // Parameters can not be abstract class types. 3703 // For record types, this is done by the AbstractClassUsageDiagnoser once 3704 // the class has been completely parsed. 3705 if (!CurContext->isRecord() && 3706 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3707 diag::err_abstract_type_in_decl, 3708 AbstractParamType)) 3709 D.setInvalidType(true); 3710 3711 QualType T = adjustParameterType(parmDeclType); 3712 3713 ParmVarDecl *New 3714 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3715 T, DInfo, StorageClass, 0); 3716 3717 if (D.isInvalidType()) 3718 New->setInvalidDecl(); 3719 3720 // Parameter declarators cannot be interface types. All ObjC objects are 3721 // passed by reference. 3722 if (T->isObjCInterfaceType()) { 3723 Diag(D.getIdentifierLoc(), 3724 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3725 New->setInvalidDecl(); 3726 } 3727 3728 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3729 if (D.getCXXScopeSpec().isSet()) { 3730 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3731 << D.getCXXScopeSpec().getRange(); 3732 New->setInvalidDecl(); 3733 } 3734 3735 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3736 // duration shall not be qualified by an address-space qualifier." 3737 // Since all parameters have automatic store duration, they can not have 3738 // an address space. 3739 if (T.getAddressSpace() != 0) { 3740 Diag(D.getIdentifierLoc(), 3741 diag::err_arg_with_address_space); 3742 New->setInvalidDecl(); 3743 } 3744 3745 3746 // Add the parameter declaration into this scope. 3747 S->AddDecl(DeclPtrTy::make(New)); 3748 if (II) 3749 IdResolver.AddDecl(New); 3750 3751 ProcessDeclAttributes(S, New, D); 3752 3753 if (New->hasAttr<BlocksAttr>()) { 3754 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3755 } 3756 return DeclPtrTy::make(New); 3757} 3758 3759void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3760 SourceLocation LocAfterDecls) { 3761 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3762 "Not a function declarator!"); 3763 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3764 3765 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3766 // for a K&R function. 3767 if (!FTI.hasPrototype) { 3768 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3769 --i; 3770 if (FTI.ArgInfo[i].Param == 0) { 3771 llvm::SmallString<256> Code; 3772 llvm::raw_svector_ostream(Code) << " int " 3773 << FTI.ArgInfo[i].Ident->getName() 3774 << ";\n"; 3775 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3776 << FTI.ArgInfo[i].Ident 3777 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3778 3779 // Implicitly declare the argument as type 'int' for lack of a better 3780 // type. 3781 DeclSpec DS; 3782 const char* PrevSpec; // unused 3783 unsigned DiagID; // unused 3784 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3785 PrevSpec, DiagID); 3786 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3787 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3788 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3789 } 3790 } 3791 } 3792} 3793 3794Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3795 Declarator &D) { 3796 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3797 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3798 "Not a function declarator!"); 3799 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3800 3801 if (FTI.hasPrototype) { 3802 // FIXME: Diagnose arguments without names in C. 3803 } 3804 3805 Scope *ParentScope = FnBodyScope->getParent(); 3806 3807 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3808 MultiTemplateParamsArg(*this), 3809 /*IsFunctionDefinition=*/true); 3810 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3811} 3812 3813Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3814 // Clear the last template instantiation error context. 3815 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 3816 3817 if (!D) 3818 return D; 3819 FunctionDecl *FD = 0; 3820 3821 if (FunctionTemplateDecl *FunTmpl 3822 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3823 FD = FunTmpl->getTemplatedDecl(); 3824 else 3825 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3826 3827 CurFunctionNeedsScopeChecking = false; 3828 3829 // See if this is a redefinition. 3830 const FunctionDecl *Definition; 3831 if (FD->getBody(Definition)) { 3832 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3833 Diag(Definition->getLocation(), diag::note_previous_definition); 3834 } 3835 3836 // Builtin functions cannot be defined. 3837 if (unsigned BuiltinID = FD->getBuiltinID()) { 3838 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3839 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3840 FD->setInvalidDecl(); 3841 } 3842 } 3843 3844 // The return type of a function definition must be complete 3845 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3846 QualType ResultType = FD->getResultType(); 3847 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3848 !FD->isInvalidDecl() && 3849 RequireCompleteType(FD->getLocation(), ResultType, 3850 diag::err_func_def_incomplete_result)) 3851 FD->setInvalidDecl(); 3852 3853 // GNU warning -Wmissing-prototypes: 3854 // Warn if a global function is defined without a previous 3855 // prototype declaration. This warning is issued even if the 3856 // definition itself provides a prototype. The aim is to detect 3857 // global functions that fail to be declared in header files. 3858 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3859 !FD->isMain()) { 3860 bool MissingPrototype = true; 3861 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3862 Prev; Prev = Prev->getPreviousDeclaration()) { 3863 // Ignore any declarations that occur in function or method 3864 // scope, because they aren't visible from the header. 3865 if (Prev->getDeclContext()->isFunctionOrMethod()) 3866 continue; 3867 3868 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3869 break; 3870 } 3871 3872 if (MissingPrototype) 3873 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3874 } 3875 3876 if (FnBodyScope) 3877 PushDeclContext(FnBodyScope, FD); 3878 3879 // Check the validity of our function parameters 3880 CheckParmsForFunctionDef(FD); 3881 3882 // Introduce our parameters into the function scope 3883 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3884 ParmVarDecl *Param = FD->getParamDecl(p); 3885 Param->setOwningFunction(FD); 3886 3887 // If this has an identifier, add it to the scope stack. 3888 if (Param->getIdentifier() && FnBodyScope) 3889 PushOnScopeChains(Param, FnBodyScope); 3890 } 3891 3892 // Checking attributes of current function definition 3893 // dllimport attribute. 3894 if (FD->getAttr<DLLImportAttr>() && 3895 (!FD->getAttr<DLLExportAttr>())) { 3896 // dllimport attribute cannot be applied to definition. 3897 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3898 Diag(FD->getLocation(), 3899 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3900 << "dllimport"; 3901 FD->setInvalidDecl(); 3902 return DeclPtrTy::make(FD); 3903 } else { 3904 // If a symbol previously declared dllimport is later defined, the 3905 // attribute is ignored in subsequent references, and a warning is 3906 // emitted. 3907 Diag(FD->getLocation(), 3908 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3909 << FD->getNameAsCString() << "dllimport"; 3910 } 3911 } 3912 return DeclPtrTy::make(FD); 3913} 3914 3915Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3916 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3917} 3918 3919Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3920 bool IsInstantiation) { 3921 Decl *dcl = D.getAs<Decl>(); 3922 Stmt *Body = BodyArg.takeAs<Stmt>(); 3923 3924 FunctionDecl *FD = 0; 3925 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3926 if (FunTmpl) 3927 FD = FunTmpl->getTemplatedDecl(); 3928 else 3929 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3930 3931 if (FD) { 3932 FD->setBody(Body); 3933 if (FD->isMain()) 3934 // C and C++ allow for main to automagically return 0. 3935 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3936 FD->setHasImplicitReturnZero(true); 3937 else 3938 CheckFallThroughForFunctionDef(FD, Body); 3939 3940 if (!FD->isInvalidDecl()) 3941 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3942 3943 // C++ [basic.def.odr]p2: 3944 // [...] A virtual member function is used if it is not pure. [...] 3945 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3946 if (Method->isVirtual() && !Method->isPure()) 3947 MarkDeclarationReferenced(Method->getLocation(), Method); 3948 3949 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3950 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3951 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3952 MD->setBody(Body); 3953 CheckFallThroughForFunctionDef(MD, Body); 3954 MD->setEndLoc(Body->getLocEnd()); 3955 3956 if (!MD->isInvalidDecl()) 3957 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3958 } else { 3959 Body->Destroy(Context); 3960 return DeclPtrTy(); 3961 } 3962 if (!IsInstantiation) 3963 PopDeclContext(); 3964 3965 // Verify and clean out per-function state. 3966 3967 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3968 3969 // Check goto/label use. 3970 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3971 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3972 LabelStmt *L = I->second; 3973 3974 // Verify that we have no forward references left. If so, there was a goto 3975 // or address of a label taken, but no definition of it. Label fwd 3976 // definitions are indicated with a null substmt. 3977 if (L->getSubStmt() != 0) 3978 continue; 3979 3980 // Emit error. 3981 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3982 3983 // At this point, we have gotos that use the bogus label. Stitch it into 3984 // the function body so that they aren't leaked and that the AST is well 3985 // formed. 3986 if (Body == 0) { 3987 // The whole function wasn't parsed correctly, just delete this. 3988 L->Destroy(Context); 3989 continue; 3990 } 3991 3992 // Otherwise, the body is valid: we want to stitch the label decl into the 3993 // function somewhere so that it is properly owned and so that the goto 3994 // has a valid target. Do this by creating a new compound stmt with the 3995 // label in it. 3996 3997 // Give the label a sub-statement. 3998 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3999 4000 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4001 cast<CXXTryStmt>(Body)->getTryBlock() : 4002 cast<CompoundStmt>(Body); 4003 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4004 Elements.push_back(L); 4005 Compound->setStmts(Context, &Elements[0], Elements.size()); 4006 } 4007 FunctionLabelMap.clear(); 4008 4009 if (!Body) return D; 4010 4011 // Verify that that gotos and switch cases don't jump into scopes illegally. 4012 if (CurFunctionNeedsScopeChecking) 4013 DiagnoseInvalidJumps(Body); 4014 4015 // C++ constructors that have function-try-blocks can't have return 4016 // statements in the handlers of that block. (C++ [except.handle]p14) 4017 // Verify this. 4018 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4019 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4020 4021 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4022 computeBaseOrMembersToDestroy(Destructor); 4023 return D; 4024} 4025 4026/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4027/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4028NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4029 IdentifierInfo &II, Scope *S) { 4030 // Before we produce a declaration for an implicitly defined 4031 // function, see whether there was a locally-scoped declaration of 4032 // this name as a function or variable. If so, use that 4033 // (non-visible) declaration, and complain about it. 4034 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4035 = LocallyScopedExternalDecls.find(&II); 4036 if (Pos != LocallyScopedExternalDecls.end()) { 4037 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4038 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4039 return Pos->second; 4040 } 4041 4042 // Extension in C99. Legal in C90, but warn about it. 4043 if (II.getName().startswith("__builtin_")) 4044 Diag(Loc, diag::warn_builtin_unknown) << &II; 4045 else if (getLangOptions().C99) 4046 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4047 else 4048 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4049 4050 // Set a Declarator for the implicit definition: int foo(); 4051 const char *Dummy; 4052 DeclSpec DS; 4053 unsigned DiagID; 4054 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4055 Error = Error; // Silence warning. 4056 assert(!Error && "Error setting up implicit decl!"); 4057 Declarator D(DS, Declarator::BlockContext); 4058 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4059 0, 0, false, SourceLocation(), 4060 false, 0,0,0, Loc, Loc, D), 4061 SourceLocation()); 4062 D.SetIdentifier(&II, Loc); 4063 4064 // Insert this function into translation-unit scope. 4065 4066 DeclContext *PrevDC = CurContext; 4067 CurContext = Context.getTranslationUnitDecl(); 4068 4069 FunctionDecl *FD = 4070 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4071 FD->setImplicit(); 4072 4073 CurContext = PrevDC; 4074 4075 AddKnownFunctionAttributes(FD); 4076 4077 return FD; 4078} 4079 4080/// \brief Adds any function attributes that we know a priori based on 4081/// the declaration of this function. 4082/// 4083/// These attributes can apply both to implicitly-declared builtins 4084/// (like __builtin___printf_chk) or to library-declared functions 4085/// like NSLog or printf. 4086void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4087 if (FD->isInvalidDecl()) 4088 return; 4089 4090 // If this is a built-in function, map its builtin attributes to 4091 // actual attributes. 4092 if (unsigned BuiltinID = FD->getBuiltinID()) { 4093 // Handle printf-formatting attributes. 4094 unsigned FormatIdx; 4095 bool HasVAListArg; 4096 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4097 if (!FD->getAttr<FormatAttr>()) 4098 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4099 HasVAListArg ? 0 : FormatIdx + 2)); 4100 } 4101 4102 // Mark const if we don't care about errno and that is the only 4103 // thing preventing the function from being const. This allows 4104 // IRgen to use LLVM intrinsics for such functions. 4105 if (!getLangOptions().MathErrno && 4106 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4107 if (!FD->getAttr<ConstAttr>()) 4108 FD->addAttr(::new (Context) ConstAttr()); 4109 } 4110 4111 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4112 FD->addAttr(::new (Context) NoReturnAttr()); 4113 } 4114 4115 IdentifierInfo *Name = FD->getIdentifier(); 4116 if (!Name) 4117 return; 4118 if ((!getLangOptions().CPlusPlus && 4119 FD->getDeclContext()->isTranslationUnit()) || 4120 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4121 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4122 LinkageSpecDecl::lang_c)) { 4123 // Okay: this could be a libc/libm/Objective-C function we know 4124 // about. 4125 } else 4126 return; 4127 4128 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4129 // FIXME: NSLog and NSLogv should be target specific 4130 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4131 // FIXME: We known better than our headers. 4132 const_cast<FormatAttr *>(Format)->setType("printf"); 4133 } else 4134 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4135 Name->isStr("NSLogv") ? 0 : 2)); 4136 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4137 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4138 // target-specific builtins, perhaps? 4139 if (!FD->getAttr<FormatAttr>()) 4140 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4141 Name->isStr("vasprintf") ? 0 : 3)); 4142 } 4143} 4144 4145TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4146 DeclaratorInfo *DInfo) { 4147 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4148 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4149 4150 if (!DInfo) { 4151 assert(D.isInvalidType() && "no declarator info for valid type"); 4152 DInfo = Context.getTrivialDeclaratorInfo(T); 4153 } 4154 4155 // Scope manipulation handled by caller. 4156 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4157 D.getIdentifierLoc(), 4158 D.getIdentifier(), 4159 DInfo); 4160 4161 if (const TagType *TT = T->getAs<TagType>()) { 4162 TagDecl *TD = TT->getDecl(); 4163 4164 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4165 // keep track of the TypedefDecl. 4166 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4167 TD->setTypedefForAnonDecl(NewTD); 4168 } 4169 4170 if (D.isInvalidType()) 4171 NewTD->setInvalidDecl(); 4172 return NewTD; 4173} 4174 4175 4176/// \brief Determine whether a tag with a given kind is acceptable 4177/// as a redeclaration of the given tag declaration. 4178/// 4179/// \returns true if the new tag kind is acceptable, false otherwise. 4180bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4181 TagDecl::TagKind NewTag, 4182 SourceLocation NewTagLoc, 4183 const IdentifierInfo &Name) { 4184 // C++ [dcl.type.elab]p3: 4185 // The class-key or enum keyword present in the 4186 // elaborated-type-specifier shall agree in kind with the 4187 // declaration to which the name in theelaborated-type-specifier 4188 // refers. This rule also applies to the form of 4189 // elaborated-type-specifier that declares a class-name or 4190 // friend class since it can be construed as referring to the 4191 // definition of the class. Thus, in any 4192 // elaborated-type-specifier, the enum keyword shall be used to 4193 // refer to an enumeration (7.2), the union class-keyshall be 4194 // used to refer to a union (clause 9), and either the class or 4195 // struct class-key shall be used to refer to a class (clause 9) 4196 // declared using the class or struct class-key. 4197 TagDecl::TagKind OldTag = Previous->getTagKind(); 4198 if (OldTag == NewTag) 4199 return true; 4200 4201 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4202 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4203 // Warn about the struct/class tag mismatch. 4204 bool isTemplate = false; 4205 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4206 isTemplate = Record->getDescribedClassTemplate(); 4207 4208 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4209 << (NewTag == TagDecl::TK_class) 4210 << isTemplate << &Name 4211 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4212 OldTag == TagDecl::TK_class? "class" : "struct"); 4213 Diag(Previous->getLocation(), diag::note_previous_use); 4214 return true; 4215 } 4216 return false; 4217} 4218 4219/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4220/// former case, Name will be non-null. In the later case, Name will be null. 4221/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4222/// reference/declaration/definition of a tag. 4223Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4224 SourceLocation KWLoc, const CXXScopeSpec &SS, 4225 IdentifierInfo *Name, SourceLocation NameLoc, 4226 AttributeList *Attr, AccessSpecifier AS, 4227 MultiTemplateParamsArg TemplateParameterLists, 4228 bool &OwnedDecl, bool &IsDependent) { 4229 // If this is not a definition, it must have a name. 4230 assert((Name != 0 || TUK == TUK_Definition) && 4231 "Nameless record must be a definition!"); 4232 4233 OwnedDecl = false; 4234 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4235 4236 // FIXME: Check explicit specializations more carefully. 4237 bool isExplicitSpecialization = false; 4238 if (TUK != TUK_Reference) { 4239 if (TemplateParameterList *TemplateParams 4240 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4241 (TemplateParameterList**)TemplateParameterLists.get(), 4242 TemplateParameterLists.size(), 4243 isExplicitSpecialization)) { 4244 if (TemplateParams->size() > 0) { 4245 // This is a declaration or definition of a class template (which may 4246 // be a member of another template). 4247 OwnedDecl = false; 4248 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4249 SS, Name, NameLoc, Attr, 4250 TemplateParams, 4251 AS); 4252 TemplateParameterLists.release(); 4253 return Result.get(); 4254 } else { 4255 // The "template<>" header is extraneous. 4256 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4257 << ElaboratedType::getNameForTagKind(Kind) << Name; 4258 isExplicitSpecialization = true; 4259 } 4260 } 4261 4262 TemplateParameterLists.release(); 4263 } 4264 4265 DeclContext *SearchDC = CurContext; 4266 DeclContext *DC = CurContext; 4267 NamedDecl *PrevDecl = 0; 4268 bool isStdBadAlloc = false; 4269 bool Invalid = false; 4270 4271 bool RedeclarationOnly = (TUK != TUK_Reference); 4272 4273 if (Name && SS.isNotEmpty()) { 4274 // We have a nested-name tag ('struct foo::bar'). 4275 4276 // Check for invalid 'foo::'. 4277 if (SS.isInvalid()) { 4278 Name = 0; 4279 goto CreateNewDecl; 4280 } 4281 4282 // If this is a friend or a reference to a class in a dependent 4283 // context, don't try to make a decl for it. 4284 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4285 DC = computeDeclContext(SS, false); 4286 if (!DC) { 4287 IsDependent = true; 4288 return DeclPtrTy(); 4289 } 4290 } 4291 4292 if (RequireCompleteDeclContext(SS)) 4293 return DeclPtrTy::make((Decl *)0); 4294 4295 DC = computeDeclContext(SS, true); 4296 SearchDC = DC; 4297 // Look-up name inside 'foo::'. 4298 LookupResult R; 4299 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4300 4301 if (R.isAmbiguous()) { 4302 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4303 return DeclPtrTy(); 4304 } 4305 4306 if (R.getKind() == LookupResult::Found) 4307 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4308 4309 // A tag 'foo::bar' must already exist. 4310 if (!PrevDecl) { 4311 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4312 Name = 0; 4313 Invalid = true; 4314 goto CreateNewDecl; 4315 } 4316 } else if (Name) { 4317 // If this is a named struct, check to see if there was a previous forward 4318 // declaration or definition. 4319 // FIXME: We're looking into outer scopes here, even when we 4320 // shouldn't be. Doing so can result in ambiguities that we 4321 // shouldn't be diagnosing. 4322 LookupResult R; 4323 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4324 if (R.isAmbiguous()) { 4325 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4326 // FIXME: This is not best way to recover from case like: 4327 // 4328 // struct S s; 4329 // 4330 // causes needless "incomplete type" error later. 4331 Name = 0; 4332 PrevDecl = 0; 4333 Invalid = true; 4334 } else 4335 PrevDecl = R.getAsSingleDecl(Context); 4336 4337 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4338 // FIXME: This makes sure that we ignore the contexts associated 4339 // with C structs, unions, and enums when looking for a matching 4340 // tag declaration or definition. See the similar lookup tweak 4341 // in Sema::LookupName; is there a better way to deal with this? 4342 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4343 SearchDC = SearchDC->getParent(); 4344 } 4345 } 4346 4347 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4348 // Maybe we will complain about the shadowed template parameter. 4349 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4350 // Just pretend that we didn't see the previous declaration. 4351 PrevDecl = 0; 4352 } 4353 4354 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4355 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4356 // This is a declaration of or a reference to "std::bad_alloc". 4357 isStdBadAlloc = true; 4358 4359 if (!PrevDecl && StdBadAlloc) { 4360 // std::bad_alloc has been implicitly declared (but made invisible to 4361 // name lookup). Fill in this implicit declaration as the previous 4362 // declaration, so that the declarations get chained appropriately. 4363 PrevDecl = StdBadAlloc; 4364 } 4365 } 4366 4367 if (PrevDecl) { 4368 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4369 // If this is a use of a previous tag, or if the tag is already declared 4370 // in the same scope (so that the definition/declaration completes or 4371 // rementions the tag), reuse the decl. 4372 if (TUK == TUK_Reference || TUK == TUK_Friend || 4373 isDeclInScope(PrevDecl, SearchDC, S)) { 4374 // Make sure that this wasn't declared as an enum and now used as a 4375 // struct or something similar. 4376 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4377 bool SafeToContinue 4378 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4379 Kind != TagDecl::TK_enum); 4380 if (SafeToContinue) 4381 Diag(KWLoc, diag::err_use_with_wrong_tag) 4382 << Name 4383 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4384 PrevTagDecl->getKindName()); 4385 else 4386 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4387 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4388 4389 if (SafeToContinue) 4390 Kind = PrevTagDecl->getTagKind(); 4391 else { 4392 // Recover by making this an anonymous redefinition. 4393 Name = 0; 4394 PrevDecl = 0; 4395 Invalid = true; 4396 } 4397 } 4398 4399 if (!Invalid) { 4400 // If this is a use, just return the declaration we found. 4401 4402 // FIXME: In the future, return a variant or some other clue 4403 // for the consumer of this Decl to know it doesn't own it. 4404 // For our current ASTs this shouldn't be a problem, but will 4405 // need to be changed with DeclGroups. 4406 if (TUK == TUK_Reference || TUK == TUK_Friend) 4407 return DeclPtrTy::make(PrevDecl); 4408 4409 // Diagnose attempts to redefine a tag. 4410 if (TUK == TUK_Definition) { 4411 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4412 // If we're defining a specialization and the previous definition 4413 // is from an implicit instantiation, don't emit an error 4414 // here; we'll catch this in the general case below. 4415 if (!isExplicitSpecialization || 4416 !isa<CXXRecordDecl>(Def) || 4417 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4418 == TSK_ExplicitSpecialization) { 4419 Diag(NameLoc, diag::err_redefinition) << Name; 4420 Diag(Def->getLocation(), diag::note_previous_definition); 4421 // If this is a redefinition, recover by making this 4422 // struct be anonymous, which will make any later 4423 // references get the previous definition. 4424 Name = 0; 4425 PrevDecl = 0; 4426 Invalid = true; 4427 } 4428 } else { 4429 // If the type is currently being defined, complain 4430 // about a nested redefinition. 4431 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4432 if (Tag->isBeingDefined()) { 4433 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4434 Diag(PrevTagDecl->getLocation(), 4435 diag::note_previous_definition); 4436 Name = 0; 4437 PrevDecl = 0; 4438 Invalid = true; 4439 } 4440 } 4441 4442 // Okay, this is definition of a previously declared or referenced 4443 // tag PrevDecl. We're going to create a new Decl for it. 4444 } 4445 } 4446 // If we get here we have (another) forward declaration or we 4447 // have a definition. Just create a new decl. 4448 4449 } else { 4450 // If we get here, this is a definition of a new tag type in a nested 4451 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4452 // new decl/type. We set PrevDecl to NULL so that the entities 4453 // have distinct types. 4454 PrevDecl = 0; 4455 } 4456 // If we get here, we're going to create a new Decl. If PrevDecl 4457 // is non-NULL, it's a definition of the tag declared by 4458 // PrevDecl. If it's NULL, we have a new definition. 4459 } else { 4460 // PrevDecl is a namespace, template, or anything else 4461 // that lives in the IDNS_Tag identifier namespace. 4462 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4463 // The tag name clashes with a namespace name, issue an error and 4464 // recover by making this tag be anonymous. 4465 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4466 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4467 Name = 0; 4468 PrevDecl = 0; 4469 Invalid = true; 4470 } else { 4471 // The existing declaration isn't relevant to us; we're in a 4472 // new scope, so clear out the previous declaration. 4473 PrevDecl = 0; 4474 } 4475 } 4476 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4477 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4478 // C++ [basic.scope.pdecl]p5: 4479 // -- for an elaborated-type-specifier of the form 4480 // 4481 // class-key identifier 4482 // 4483 // if the elaborated-type-specifier is used in the 4484 // decl-specifier-seq or parameter-declaration-clause of a 4485 // function defined in namespace scope, the identifier is 4486 // declared as a class-name in the namespace that contains 4487 // the declaration; otherwise, except as a friend 4488 // declaration, the identifier is declared in the smallest 4489 // non-class, non-function-prototype scope that contains the 4490 // declaration. 4491 // 4492 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4493 // C structs and unions. 4494 // 4495 // GNU C also supports this behavior as part of its incomplete 4496 // enum types extension, while GNU C++ does not. 4497 // 4498 // Find the context where we'll be declaring the tag. 4499 // FIXME: We would like to maintain the current DeclContext as the 4500 // lexical context, 4501 while (SearchDC->isRecord()) 4502 SearchDC = SearchDC->getParent(); 4503 4504 // Find the scope where we'll be declaring the tag. 4505 while (S->isClassScope() || 4506 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4507 ((S->getFlags() & Scope::DeclScope) == 0) || 4508 (S->getEntity() && 4509 ((DeclContext *)S->getEntity())->isTransparentContext())) 4510 S = S->getParent(); 4511 4512 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4513 // C++ [namespace.memdef]p3: 4514 // If a friend declaration in a non-local class first declares a 4515 // class or function, the friend class or function is a member of 4516 // the innermost enclosing namespace. 4517 while (!SearchDC->isFileContext()) 4518 SearchDC = SearchDC->getParent(); 4519 4520 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4521 while (S->getEntity() != SearchDC) 4522 S = S->getParent(); 4523 } 4524 4525CreateNewDecl: 4526 4527 // If there is an identifier, use the location of the identifier as the 4528 // location of the decl, otherwise use the location of the struct/union 4529 // keyword. 4530 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4531 4532 // Otherwise, create a new declaration. If there is a previous 4533 // declaration of the same entity, the two will be linked via 4534 // PrevDecl. 4535 TagDecl *New; 4536 4537 if (Kind == TagDecl::TK_enum) { 4538 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4539 // enum X { A, B, C } D; D should chain to X. 4540 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4541 cast_or_null<EnumDecl>(PrevDecl)); 4542 // If this is an undefined enum, warn. 4543 if (TUK != TUK_Definition && !Invalid) { 4544 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4545 : diag::ext_forward_ref_enum; 4546 Diag(Loc, DK); 4547 } 4548 } else { 4549 // struct/union/class 4550 4551 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4552 // struct X { int A; } D; D should chain to X. 4553 if (getLangOptions().CPlusPlus) { 4554 // FIXME: Look for a way to use RecordDecl for simple structs. 4555 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4556 cast_or_null<CXXRecordDecl>(PrevDecl)); 4557 4558 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4559 StdBadAlloc = cast<CXXRecordDecl>(New); 4560 } else 4561 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4562 cast_or_null<RecordDecl>(PrevDecl)); 4563 } 4564 4565 if (Kind != TagDecl::TK_enum) { 4566 // Handle #pragma pack: if the #pragma pack stack has non-default 4567 // alignment, make up a packed attribute for this decl. These 4568 // attributes are checked when the ASTContext lays out the 4569 // structure. 4570 // 4571 // It is important for implementing the correct semantics that this 4572 // happen here (in act on tag decl). The #pragma pack stack is 4573 // maintained as a result of parser callbacks which can occur at 4574 // many points during the parsing of a struct declaration (because 4575 // the #pragma tokens are effectively skipped over during the 4576 // parsing of the struct). 4577 if (unsigned Alignment = getPragmaPackAlignment()) 4578 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4579 } 4580 4581 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4582 // C++ [dcl.typedef]p3: 4583 // [...] Similarly, in a given scope, a class or enumeration 4584 // shall not be declared with the same name as a typedef-name 4585 // that is declared in that scope and refers to a type other 4586 // than the class or enumeration itself. 4587 LookupResult Lookup; 4588 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4589 TypedefDecl *PrevTypedef = 0; 4590 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4591 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4592 4593 NamedDecl *PrevTypedefNamed = PrevTypedef; 4594 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4595 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4596 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4597 Diag(Loc, diag::err_tag_definition_of_typedef) 4598 << Context.getTypeDeclType(New) 4599 << PrevTypedef->getUnderlyingType(); 4600 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4601 Invalid = true; 4602 } 4603 } 4604 4605 // If this is a specialization of a member class (of a class template), 4606 // check the specialization. 4607 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4608 Invalid = true; 4609 4610 if (Invalid) 4611 New->setInvalidDecl(); 4612 4613 if (Attr) 4614 ProcessDeclAttributeList(S, New, Attr); 4615 4616 // If we're declaring or defining a tag in function prototype scope 4617 // in C, note that this type can only be used within the function. 4618 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4619 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4620 4621 // Set the lexical context. If the tag has a C++ scope specifier, the 4622 // lexical context will be different from the semantic context. 4623 New->setLexicalDeclContext(CurContext); 4624 4625 // Mark this as a friend decl if applicable. 4626 if (TUK == TUK_Friend) 4627 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4628 4629 // Set the access specifier. 4630 if (!Invalid && TUK != TUK_Friend) 4631 SetMemberAccessSpecifier(New, PrevDecl, AS); 4632 4633 if (TUK == TUK_Definition) 4634 New->startDefinition(); 4635 4636 // If this has an identifier, add it to the scope stack. 4637 if (TUK == TUK_Friend) { 4638 // We might be replacing an existing declaration in the lookup tables; 4639 // if so, borrow its access specifier. 4640 if (PrevDecl) 4641 New->setAccess(PrevDecl->getAccess()); 4642 4643 // Friend tag decls are visible in fairly strange ways. 4644 if (!CurContext->isDependentContext()) { 4645 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4646 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4647 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4648 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4649 } 4650 } else if (Name) { 4651 S = getNonFieldDeclScope(S); 4652 PushOnScopeChains(New, S); 4653 } else { 4654 CurContext->addDecl(New); 4655 } 4656 4657 // If this is the C FILE type, notify the AST context. 4658 if (IdentifierInfo *II = New->getIdentifier()) 4659 if (!New->isInvalidDecl() && 4660 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4661 II->isStr("FILE")) 4662 Context.setFILEDecl(New); 4663 4664 OwnedDecl = true; 4665 return DeclPtrTy::make(New); 4666} 4667 4668void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4669 AdjustDeclIfTemplate(TagD); 4670 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4671 4672 // Enter the tag context. 4673 PushDeclContext(S, Tag); 4674 4675 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4676 FieldCollector->StartClass(); 4677 4678 if (Record->getIdentifier()) { 4679 // C++ [class]p2: 4680 // [...] The class-name is also inserted into the scope of the 4681 // class itself; this is known as the injected-class-name. For 4682 // purposes of access checking, the injected-class-name is treated 4683 // as if it were a public member name. 4684 CXXRecordDecl *InjectedClassName 4685 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4686 CurContext, Record->getLocation(), 4687 Record->getIdentifier(), 4688 Record->getTagKeywordLoc(), 4689 Record); 4690 InjectedClassName->setImplicit(); 4691 InjectedClassName->setAccess(AS_public); 4692 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4693 InjectedClassName->setDescribedClassTemplate(Template); 4694 PushOnScopeChains(InjectedClassName, S); 4695 assert(InjectedClassName->isInjectedClassName() && 4696 "Broken injected-class-name"); 4697 } 4698 } 4699} 4700 4701void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4702 SourceLocation RBraceLoc) { 4703 AdjustDeclIfTemplate(TagD); 4704 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4705 Tag->setRBraceLoc(RBraceLoc); 4706 4707 if (isa<CXXRecordDecl>(Tag)) 4708 FieldCollector->FinishClass(); 4709 4710 // Exit this scope of this tag's definition. 4711 PopDeclContext(); 4712 4713 // Notify the consumer that we've defined a tag. 4714 Consumer.HandleTagDeclDefinition(Tag); 4715} 4716 4717// Note that FieldName may be null for anonymous bitfields. 4718bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4719 QualType FieldTy, const Expr *BitWidth, 4720 bool *ZeroWidth) { 4721 // Default to true; that shouldn't confuse checks for emptiness 4722 if (ZeroWidth) 4723 *ZeroWidth = true; 4724 4725 // C99 6.7.2.1p4 - verify the field type. 4726 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4727 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4728 // Handle incomplete types with specific error. 4729 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4730 return true; 4731 if (FieldName) 4732 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4733 << FieldName << FieldTy << BitWidth->getSourceRange(); 4734 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4735 << FieldTy << BitWidth->getSourceRange(); 4736 } 4737 4738 // If the bit-width is type- or value-dependent, don't try to check 4739 // it now. 4740 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4741 return false; 4742 4743 llvm::APSInt Value; 4744 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4745 return true; 4746 4747 if (Value != 0 && ZeroWidth) 4748 *ZeroWidth = false; 4749 4750 // Zero-width bitfield is ok for anonymous field. 4751 if (Value == 0 && FieldName) 4752 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4753 4754 if (Value.isSigned() && Value.isNegative()) { 4755 if (FieldName) 4756 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4757 << FieldName << Value.toString(10); 4758 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4759 << Value.toString(10); 4760 } 4761 4762 if (!FieldTy->isDependentType()) { 4763 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4764 if (Value.getZExtValue() > TypeSize) { 4765 if (FieldName) 4766 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4767 << FieldName << (unsigned)TypeSize; 4768 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4769 << (unsigned)TypeSize; 4770 } 4771 } 4772 4773 return false; 4774} 4775 4776/// ActOnField - Each field of a struct/union/class is passed into this in order 4777/// to create a FieldDecl object for it. 4778Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4779 SourceLocation DeclStart, 4780 Declarator &D, ExprTy *BitfieldWidth) { 4781 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4782 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4783 AS_public); 4784 return DeclPtrTy::make(Res); 4785} 4786 4787/// HandleField - Analyze a field of a C struct or a C++ data member. 4788/// 4789FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4790 SourceLocation DeclStart, 4791 Declarator &D, Expr *BitWidth, 4792 AccessSpecifier AS) { 4793 IdentifierInfo *II = D.getIdentifier(); 4794 SourceLocation Loc = DeclStart; 4795 if (II) Loc = D.getIdentifierLoc(); 4796 4797 DeclaratorInfo *DInfo = 0; 4798 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4799 if (getLangOptions().CPlusPlus) 4800 CheckExtraCXXDefaultArguments(D); 4801 4802 DiagnoseFunctionSpecifiers(D); 4803 4804 if (D.getDeclSpec().isThreadSpecified()) 4805 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4806 4807 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4808 4809 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4810 // Maybe we will complain about the shadowed template parameter. 4811 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4812 // Just pretend that we didn't see the previous declaration. 4813 PrevDecl = 0; 4814 } 4815 4816 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4817 PrevDecl = 0; 4818 4819 bool Mutable 4820 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4821 SourceLocation TSSL = D.getSourceRange().getBegin(); 4822 FieldDecl *NewFD 4823 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4824 AS, PrevDecl, &D); 4825 if (NewFD->isInvalidDecl() && PrevDecl) { 4826 // Don't introduce NewFD into scope; there's already something 4827 // with the same name in the same scope. 4828 } else if (II) { 4829 PushOnScopeChains(NewFD, S); 4830 } else 4831 Record->addDecl(NewFD); 4832 4833 return NewFD; 4834} 4835 4836/// \brief Build a new FieldDecl and check its well-formedness. 4837/// 4838/// This routine builds a new FieldDecl given the fields name, type, 4839/// record, etc. \p PrevDecl should refer to any previous declaration 4840/// with the same name and in the same scope as the field to be 4841/// created. 4842/// 4843/// \returns a new FieldDecl. 4844/// 4845/// \todo The Declarator argument is a hack. It will be removed once 4846FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4847 DeclaratorInfo *DInfo, 4848 RecordDecl *Record, SourceLocation Loc, 4849 bool Mutable, Expr *BitWidth, 4850 SourceLocation TSSL, 4851 AccessSpecifier AS, NamedDecl *PrevDecl, 4852 Declarator *D) { 4853 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4854 bool InvalidDecl = false; 4855 if (D) InvalidDecl = D->isInvalidType(); 4856 4857 // If we receive a broken type, recover by assuming 'int' and 4858 // marking this declaration as invalid. 4859 if (T.isNull()) { 4860 InvalidDecl = true; 4861 T = Context.IntTy; 4862 } 4863 4864 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4865 // than a variably modified type. 4866 if (T->isVariablyModifiedType()) { 4867 bool SizeIsNegative; 4868 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4869 SizeIsNegative); 4870 if (!FixedTy.isNull()) { 4871 Diag(Loc, diag::warn_illegal_constant_array_size); 4872 T = FixedTy; 4873 } else { 4874 if (SizeIsNegative) 4875 Diag(Loc, diag::err_typecheck_negative_array_size); 4876 else 4877 Diag(Loc, diag::err_typecheck_field_variable_size); 4878 InvalidDecl = true; 4879 } 4880 } 4881 4882 // Fields can not have abstract class types 4883 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4884 AbstractFieldType)) 4885 InvalidDecl = true; 4886 4887 bool ZeroWidth = false; 4888 // If this is declared as a bit-field, check the bit-field. 4889 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4890 InvalidDecl = true; 4891 DeleteExpr(BitWidth); 4892 BitWidth = 0; 4893 ZeroWidth = false; 4894 } 4895 4896 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4897 BitWidth, Mutable); 4898 if (InvalidDecl) 4899 NewFD->setInvalidDecl(); 4900 4901 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4902 Diag(Loc, diag::err_duplicate_member) << II; 4903 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4904 NewFD->setInvalidDecl(); 4905 } 4906 4907 if (getLangOptions().CPlusPlus) { 4908 QualType EltTy = Context.getBaseElementType(T); 4909 4910 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4911 4912 if (!T->isPODType()) 4913 CXXRecord->setPOD(false); 4914 if (!ZeroWidth) 4915 CXXRecord->setEmpty(false); 4916 4917 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4918 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4919 4920 if (!RDecl->hasTrivialConstructor()) 4921 CXXRecord->setHasTrivialConstructor(false); 4922 if (!RDecl->hasTrivialCopyConstructor()) 4923 CXXRecord->setHasTrivialCopyConstructor(false); 4924 if (!RDecl->hasTrivialCopyAssignment()) 4925 CXXRecord->setHasTrivialCopyAssignment(false); 4926 if (!RDecl->hasTrivialDestructor()) 4927 CXXRecord->setHasTrivialDestructor(false); 4928 4929 // C++ 9.5p1: An object of a class with a non-trivial 4930 // constructor, a non-trivial copy constructor, a non-trivial 4931 // destructor, or a non-trivial copy assignment operator 4932 // cannot be a member of a union, nor can an array of such 4933 // objects. 4934 // TODO: C++0x alters this restriction significantly. 4935 if (Record->isUnion()) { 4936 // We check for copy constructors before constructors 4937 // because otherwise we'll never get complaints about 4938 // copy constructors. 4939 4940 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4941 4942 CXXSpecialMember member; 4943 if (!RDecl->hasTrivialCopyConstructor()) 4944 member = CXXCopyConstructor; 4945 else if (!RDecl->hasTrivialConstructor()) 4946 member = CXXDefaultConstructor; 4947 else if (!RDecl->hasTrivialCopyAssignment()) 4948 member = CXXCopyAssignment; 4949 else if (!RDecl->hasTrivialDestructor()) 4950 member = CXXDestructor; 4951 else 4952 member = invalid; 4953 4954 if (member != invalid) { 4955 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4956 DiagnoseNontrivial(RT, member); 4957 NewFD->setInvalidDecl(); 4958 } 4959 } 4960 } 4961 } 4962 4963 // FIXME: We need to pass in the attributes given an AST 4964 // representation, not a parser representation. 4965 if (D) 4966 // FIXME: What to pass instead of TUScope? 4967 ProcessDeclAttributes(TUScope, NewFD, *D); 4968 4969 if (T.isObjCGCWeak()) 4970 Diag(Loc, diag::warn_attribute_weak_on_field); 4971 4972 NewFD->setAccess(AS); 4973 4974 // C++ [dcl.init.aggr]p1: 4975 // An aggregate is an array or a class (clause 9) with [...] no 4976 // private or protected non-static data members (clause 11). 4977 // A POD must be an aggregate. 4978 if (getLangOptions().CPlusPlus && 4979 (AS == AS_private || AS == AS_protected)) { 4980 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4981 CXXRecord->setAggregate(false); 4982 CXXRecord->setPOD(false); 4983 } 4984 4985 return NewFD; 4986} 4987 4988/// DiagnoseNontrivial - Given that a class has a non-trivial 4989/// special member, figure out why. 4990void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4991 QualType QT(T, 0U); 4992 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4993 4994 // Check whether the member was user-declared. 4995 switch (member) { 4996 case CXXDefaultConstructor: 4997 if (RD->hasUserDeclaredConstructor()) { 4998 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4999 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5000 const FunctionDecl *body = 0; 5001 ci->getBody(body); 5002 if (!body || 5003 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5004 SourceLocation CtorLoc = ci->getLocation(); 5005 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5006 return; 5007 } 5008 } 5009 5010 assert(0 && "found no user-declared constructors"); 5011 return; 5012 } 5013 break; 5014 5015 case CXXCopyConstructor: 5016 if (RD->hasUserDeclaredCopyConstructor()) { 5017 SourceLocation CtorLoc = 5018 RD->getCopyConstructor(Context, 0)->getLocation(); 5019 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5020 return; 5021 } 5022 break; 5023 5024 case CXXCopyAssignment: 5025 if (RD->hasUserDeclaredCopyAssignment()) { 5026 // FIXME: this should use the location of the copy 5027 // assignment, not the type. 5028 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5029 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5030 return; 5031 } 5032 break; 5033 5034 case CXXDestructor: 5035 if (RD->hasUserDeclaredDestructor()) { 5036 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5037 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5038 return; 5039 } 5040 break; 5041 } 5042 5043 typedef CXXRecordDecl::base_class_iterator base_iter; 5044 5045 // Virtual bases and members inhibit trivial copying/construction, 5046 // but not trivial destruction. 5047 if (member != CXXDestructor) { 5048 // Check for virtual bases. vbases includes indirect virtual bases, 5049 // so we just iterate through the direct bases. 5050 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5051 if (bi->isVirtual()) { 5052 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5053 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5054 return; 5055 } 5056 5057 // Check for virtual methods. 5058 typedef CXXRecordDecl::method_iterator meth_iter; 5059 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5060 ++mi) { 5061 if (mi->isVirtual()) { 5062 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5063 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5064 return; 5065 } 5066 } 5067 } 5068 5069 bool (CXXRecordDecl::*hasTrivial)() const; 5070 switch (member) { 5071 case CXXDefaultConstructor: 5072 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5073 case CXXCopyConstructor: 5074 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5075 case CXXCopyAssignment: 5076 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5077 case CXXDestructor: 5078 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5079 default: 5080 assert(0 && "unexpected special member"); return; 5081 } 5082 5083 // Check for nontrivial bases (and recurse). 5084 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5085 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5086 assert(BaseRT && "Don't know how to handle dependent bases"); 5087 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5088 if (!(BaseRecTy->*hasTrivial)()) { 5089 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5090 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5091 DiagnoseNontrivial(BaseRT, member); 5092 return; 5093 } 5094 } 5095 5096 // Check for nontrivial members (and recurse). 5097 typedef RecordDecl::field_iterator field_iter; 5098 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5099 ++fi) { 5100 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5101 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5102 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5103 5104 if (!(EltRD->*hasTrivial)()) { 5105 SourceLocation FLoc = (*fi)->getLocation(); 5106 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5107 DiagnoseNontrivial(EltRT, member); 5108 return; 5109 } 5110 } 5111 } 5112 5113 assert(0 && "found no explanation for non-trivial member"); 5114} 5115 5116/// TranslateIvarVisibility - Translate visibility from a token ID to an 5117/// AST enum value. 5118static ObjCIvarDecl::AccessControl 5119TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5120 switch (ivarVisibility) { 5121 default: assert(0 && "Unknown visitibility kind"); 5122 case tok::objc_private: return ObjCIvarDecl::Private; 5123 case tok::objc_public: return ObjCIvarDecl::Public; 5124 case tok::objc_protected: return ObjCIvarDecl::Protected; 5125 case tok::objc_package: return ObjCIvarDecl::Package; 5126 } 5127} 5128 5129/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5130/// in order to create an IvarDecl object for it. 5131Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5132 SourceLocation DeclStart, 5133 DeclPtrTy IntfDecl, 5134 Declarator &D, ExprTy *BitfieldWidth, 5135 tok::ObjCKeywordKind Visibility) { 5136 5137 IdentifierInfo *II = D.getIdentifier(); 5138 Expr *BitWidth = (Expr*)BitfieldWidth; 5139 SourceLocation Loc = DeclStart; 5140 if (II) Loc = D.getIdentifierLoc(); 5141 5142 // FIXME: Unnamed fields can be handled in various different ways, for 5143 // example, unnamed unions inject all members into the struct namespace! 5144 5145 DeclaratorInfo *DInfo = 0; 5146 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5147 5148 if (BitWidth) { 5149 // 6.7.2.1p3, 6.7.2.1p4 5150 if (VerifyBitField(Loc, II, T, BitWidth)) { 5151 D.setInvalidType(); 5152 DeleteExpr(BitWidth); 5153 BitWidth = 0; 5154 } 5155 } else { 5156 // Not a bitfield. 5157 5158 // validate II. 5159 5160 } 5161 5162 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5163 // than a variably modified type. 5164 if (T->isVariablyModifiedType()) { 5165 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5166 D.setInvalidType(); 5167 } 5168 5169 // Get the visibility (access control) for this ivar. 5170 ObjCIvarDecl::AccessControl ac = 5171 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5172 : ObjCIvarDecl::None; 5173 // Must set ivar's DeclContext to its enclosing interface. 5174 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5175 DeclContext *EnclosingContext; 5176 if (ObjCImplementationDecl *IMPDecl = 5177 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5178 // Case of ivar declared in an implementation. Context is that of its class. 5179 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5180 assert(IDecl && "No class- ActOnIvar"); 5181 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5182 } else 5183 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5184 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5185 5186 // Construct the decl. 5187 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5188 EnclosingContext, Loc, II, T, 5189 DInfo, ac, (Expr *)BitfieldWidth); 5190 5191 if (II) { 5192 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5193 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5194 && !isa<TagDecl>(PrevDecl)) { 5195 Diag(Loc, diag::err_duplicate_member) << II; 5196 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5197 NewID->setInvalidDecl(); 5198 } 5199 } 5200 5201 // Process attributes attached to the ivar. 5202 ProcessDeclAttributes(S, NewID, D); 5203 5204 if (D.isInvalidType()) 5205 NewID->setInvalidDecl(); 5206 5207 if (II) { 5208 // FIXME: When interfaces are DeclContexts, we'll need to add 5209 // these to the interface. 5210 S->AddDecl(DeclPtrTy::make(NewID)); 5211 IdResolver.AddDecl(NewID); 5212 } 5213 5214 return DeclPtrTy::make(NewID); 5215} 5216 5217void Sema::ActOnFields(Scope* S, 5218 SourceLocation RecLoc, DeclPtrTy RecDecl, 5219 DeclPtrTy *Fields, unsigned NumFields, 5220 SourceLocation LBrac, SourceLocation RBrac, 5221 AttributeList *Attr) { 5222 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5223 assert(EnclosingDecl && "missing record or interface decl"); 5224 5225 // If the decl this is being inserted into is invalid, then it may be a 5226 // redeclaration or some other bogus case. Don't try to add fields to it. 5227 if (EnclosingDecl->isInvalidDecl()) { 5228 // FIXME: Deallocate fields? 5229 return; 5230 } 5231 5232 5233 // Verify that all the fields are okay. 5234 unsigned NumNamedMembers = 0; 5235 llvm::SmallVector<FieldDecl*, 32> RecFields; 5236 5237 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5238 for (unsigned i = 0; i != NumFields; ++i) { 5239 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5240 5241 // Get the type for the field. 5242 Type *FDTy = FD->getType().getTypePtr(); 5243 5244 if (!FD->isAnonymousStructOrUnion()) { 5245 // Remember all fields written by the user. 5246 RecFields.push_back(FD); 5247 } 5248 5249 // If the field is already invalid for some reason, don't emit more 5250 // diagnostics about it. 5251 if (FD->isInvalidDecl()) 5252 continue; 5253 5254 // C99 6.7.2.1p2: 5255 // A structure or union shall not contain a member with 5256 // incomplete or function type (hence, a structure shall not 5257 // contain an instance of itself, but may contain a pointer to 5258 // an instance of itself), except that the last member of a 5259 // structure with more than one named member may have incomplete 5260 // array type; such a structure (and any union containing, 5261 // possibly recursively, a member that is such a structure) 5262 // shall not be a member of a structure or an element of an 5263 // array. 5264 if (FDTy->isFunctionType()) { 5265 // Field declared as a function. 5266 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5267 << FD->getDeclName(); 5268 FD->setInvalidDecl(); 5269 EnclosingDecl->setInvalidDecl(); 5270 continue; 5271 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5272 Record && Record->isStruct()) { 5273 // Flexible array member. 5274 if (NumNamedMembers < 1) { 5275 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5276 << FD->getDeclName(); 5277 FD->setInvalidDecl(); 5278 EnclosingDecl->setInvalidDecl(); 5279 continue; 5280 } 5281 // Okay, we have a legal flexible array member at the end of the struct. 5282 if (Record) 5283 Record->setHasFlexibleArrayMember(true); 5284 } else if (!FDTy->isDependentType() && 5285 RequireCompleteType(FD->getLocation(), FD->getType(), 5286 diag::err_field_incomplete)) { 5287 // Incomplete type 5288 FD->setInvalidDecl(); 5289 EnclosingDecl->setInvalidDecl(); 5290 continue; 5291 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5292 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5293 // If this is a member of a union, then entire union becomes "flexible". 5294 if (Record && Record->isUnion()) { 5295 Record->setHasFlexibleArrayMember(true); 5296 } else { 5297 // If this is a struct/class and this is not the last element, reject 5298 // it. Note that GCC supports variable sized arrays in the middle of 5299 // structures. 5300 if (i != NumFields-1) 5301 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5302 << FD->getDeclName() << FD->getType(); 5303 else { 5304 // We support flexible arrays at the end of structs in 5305 // other structs as an extension. 5306 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5307 << FD->getDeclName(); 5308 if (Record) 5309 Record->setHasFlexibleArrayMember(true); 5310 } 5311 } 5312 } 5313 if (Record && FDTTy->getDecl()->hasObjectMember()) 5314 Record->setHasObjectMember(true); 5315 } else if (FDTy->isObjCInterfaceType()) { 5316 /// A field cannot be an Objective-c object 5317 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5318 FD->setInvalidDecl(); 5319 EnclosingDecl->setInvalidDecl(); 5320 continue; 5321 } else if (getLangOptions().ObjC1 && 5322 getLangOptions().getGCMode() != LangOptions::NonGC && 5323 Record && 5324 (FD->getType()->isObjCObjectPointerType() || 5325 FD->getType().isObjCGCStrong())) 5326 Record->setHasObjectMember(true); 5327 // Keep track of the number of named members. 5328 if (FD->getIdentifier()) 5329 ++NumNamedMembers; 5330 } 5331 5332 // Okay, we successfully defined 'Record'. 5333 if (Record) { 5334 Record->completeDefinition(Context); 5335 } else { 5336 ObjCIvarDecl **ClsFields = 5337 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5338 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5339 ID->setIVarList(ClsFields, RecFields.size(), Context); 5340 ID->setLocEnd(RBrac); 5341 // Add ivar's to class's DeclContext. 5342 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5343 ClsFields[i]->setLexicalDeclContext(ID); 5344 ID->addDecl(ClsFields[i]); 5345 } 5346 // Must enforce the rule that ivars in the base classes may not be 5347 // duplicates. 5348 if (ID->getSuperClass()) { 5349 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5350 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5351 ObjCIvarDecl* Ivar = (*IVI); 5352 5353 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5354 ObjCIvarDecl* prevIvar = 5355 ID->getSuperClass()->lookupInstanceVariable(II); 5356 if (prevIvar) { 5357 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5358 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5359 } 5360 } 5361 } 5362 } 5363 } else if (ObjCImplementationDecl *IMPDecl = 5364 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5365 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5366 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5367 // Ivar declared in @implementation never belongs to the implementation. 5368 // Only it is in implementation's lexical context. 5369 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5370 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5371 } 5372 } 5373 5374 if (Attr) 5375 ProcessDeclAttributeList(S, Record, Attr); 5376} 5377 5378EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5379 EnumConstantDecl *LastEnumConst, 5380 SourceLocation IdLoc, 5381 IdentifierInfo *Id, 5382 ExprArg val) { 5383 Expr *Val = (Expr *)val.get(); 5384 5385 llvm::APSInt EnumVal(32); 5386 QualType EltTy; 5387 if (Val) { 5388 if (Val->isTypeDependent()) 5389 EltTy = Context.DependentTy; 5390 else { 5391 // Make sure to promote the operand type to int. 5392 UsualUnaryConversions(Val); 5393 if (Val != val.get()) { 5394 val.release(); 5395 val = Val; 5396 } 5397 5398 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5399 SourceLocation ExpLoc; 5400 if (!Val->isValueDependent() && 5401 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5402 Val = 0; 5403 } else { 5404 EltTy = Val->getType(); 5405 } 5406 } 5407 } 5408 5409 if (!Val) { 5410 if (LastEnumConst) { 5411 // Assign the last value + 1. 5412 EnumVal = LastEnumConst->getInitVal(); 5413 ++EnumVal; 5414 5415 // Check for overflow on increment. 5416 if (EnumVal < LastEnumConst->getInitVal()) 5417 Diag(IdLoc, diag::warn_enum_value_overflow); 5418 5419 EltTy = LastEnumConst->getType(); 5420 } else { 5421 // First value, set to zero. 5422 EltTy = Context.IntTy; 5423 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5424 } 5425 } 5426 5427 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5428 5429 val.release(); 5430 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5431 Val, EnumVal); 5432} 5433 5434 5435Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5436 DeclPtrTy lastEnumConst, 5437 SourceLocation IdLoc, 5438 IdentifierInfo *Id, 5439 SourceLocation EqualLoc, ExprTy *val) { 5440 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5441 EnumConstantDecl *LastEnumConst = 5442 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5443 Expr *Val = static_cast<Expr*>(val); 5444 5445 // The scope passed in may not be a decl scope. Zip up the scope tree until 5446 // we find one that is. 5447 S = getNonFieldDeclScope(S); 5448 5449 // Verify that there isn't already something declared with this name in this 5450 // scope. 5451 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5452 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5453 // Maybe we will complain about the shadowed template parameter. 5454 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5455 // Just pretend that we didn't see the previous declaration. 5456 PrevDecl = 0; 5457 } 5458 5459 if (PrevDecl) { 5460 // When in C++, we may get a TagDecl with the same name; in this case the 5461 // enum constant will 'hide' the tag. 5462 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5463 "Received TagDecl when not in C++!"); 5464 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5465 if (isa<EnumConstantDecl>(PrevDecl)) 5466 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5467 else 5468 Diag(IdLoc, diag::err_redefinition) << Id; 5469 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5470 if (Val) Val->Destroy(Context); 5471 return DeclPtrTy(); 5472 } 5473 } 5474 5475 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5476 IdLoc, Id, Owned(Val)); 5477 5478 // Register this decl in the current scope stack. 5479 if (New) 5480 PushOnScopeChains(New, S); 5481 5482 return DeclPtrTy::make(New); 5483} 5484 5485void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5486 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5487 DeclPtrTy *Elements, unsigned NumElements, 5488 Scope *S, AttributeList *Attr) { 5489 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5490 QualType EnumType = Context.getTypeDeclType(Enum); 5491 5492 if (Attr) 5493 ProcessDeclAttributeList(S, Enum, Attr); 5494 5495 // TODO: If the result value doesn't fit in an int, it must be a long or long 5496 // long value. ISO C does not support this, but GCC does as an extension, 5497 // emit a warning. 5498 unsigned IntWidth = Context.Target.getIntWidth(); 5499 unsigned CharWidth = Context.Target.getCharWidth(); 5500 unsigned ShortWidth = Context.Target.getShortWidth(); 5501 5502 // Verify that all the values are okay, compute the size of the values, and 5503 // reverse the list. 5504 unsigned NumNegativeBits = 0; 5505 unsigned NumPositiveBits = 0; 5506 5507 // Keep track of whether all elements have type int. 5508 bool AllElementsInt = true; 5509 5510 for (unsigned i = 0; i != NumElements; ++i) { 5511 EnumConstantDecl *ECD = 5512 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5513 if (!ECD) continue; // Already issued a diagnostic. 5514 5515 // If the enum value doesn't fit in an int, emit an extension warning. 5516 const llvm::APSInt &InitVal = ECD->getInitVal(); 5517 assert(InitVal.getBitWidth() >= IntWidth && 5518 "Should have promoted value to int"); 5519 if (InitVal.getBitWidth() > IntWidth) { 5520 llvm::APSInt V(InitVal); 5521 V.trunc(IntWidth); 5522 V.extend(InitVal.getBitWidth()); 5523 if (V != InitVal) 5524 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5525 << InitVal.toString(10); 5526 } 5527 5528 // Keep track of the size of positive and negative values. 5529 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5530 NumPositiveBits = std::max(NumPositiveBits, 5531 (unsigned)InitVal.getActiveBits()); 5532 else 5533 NumNegativeBits = std::max(NumNegativeBits, 5534 (unsigned)InitVal.getMinSignedBits()); 5535 5536 // Keep track of whether every enum element has type int (very commmon). 5537 if (AllElementsInt) 5538 AllElementsInt = ECD->getType() == Context.IntTy; 5539 } 5540 5541 // Figure out the type that should be used for this enum. 5542 // FIXME: Support -fshort-enums. 5543 QualType BestType; 5544 unsigned BestWidth; 5545 5546 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5547 5548 if (NumNegativeBits) { 5549 // If there is a negative value, figure out the smallest integer type (of 5550 // int/long/longlong) that fits. 5551 // If it's packed, check also if it fits a char or a short. 5552 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5553 BestType = Context.SignedCharTy; 5554 BestWidth = CharWidth; 5555 } else if (Packed && NumNegativeBits <= ShortWidth && 5556 NumPositiveBits < ShortWidth) { 5557 BestType = Context.ShortTy; 5558 BestWidth = ShortWidth; 5559 } 5560 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5561 BestType = Context.IntTy; 5562 BestWidth = IntWidth; 5563 } else { 5564 BestWidth = Context.Target.getLongWidth(); 5565 5566 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5567 BestType = Context.LongTy; 5568 else { 5569 BestWidth = Context.Target.getLongLongWidth(); 5570 5571 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5572 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5573 BestType = Context.LongLongTy; 5574 } 5575 } 5576 } else { 5577 // If there is no negative value, figure out which of uint, ulong, ulonglong 5578 // fits. 5579 // If it's packed, check also if it fits a char or a short. 5580 if (Packed && NumPositiveBits <= CharWidth) { 5581 BestType = Context.UnsignedCharTy; 5582 BestWidth = CharWidth; 5583 } else if (Packed && NumPositiveBits <= ShortWidth) { 5584 BestType = Context.UnsignedShortTy; 5585 BestWidth = ShortWidth; 5586 } 5587 else if (NumPositiveBits <= IntWidth) { 5588 BestType = Context.UnsignedIntTy; 5589 BestWidth = IntWidth; 5590 } else if (NumPositiveBits <= 5591 (BestWidth = Context.Target.getLongWidth())) { 5592 BestType = Context.UnsignedLongTy; 5593 } else { 5594 BestWidth = Context.Target.getLongLongWidth(); 5595 assert(NumPositiveBits <= BestWidth && 5596 "How could an initializer get larger than ULL?"); 5597 BestType = Context.UnsignedLongLongTy; 5598 } 5599 } 5600 5601 // Loop over all of the enumerator constants, changing their types to match 5602 // the type of the enum if needed. 5603 for (unsigned i = 0; i != NumElements; ++i) { 5604 EnumConstantDecl *ECD = 5605 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5606 if (!ECD) continue; // Already issued a diagnostic. 5607 5608 // Standard C says the enumerators have int type, but we allow, as an 5609 // extension, the enumerators to be larger than int size. If each 5610 // enumerator value fits in an int, type it as an int, otherwise type it the 5611 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5612 // that X has type 'int', not 'unsigned'. 5613 if (ECD->getType() == Context.IntTy) { 5614 // Make sure the init value is signed. 5615 llvm::APSInt IV = ECD->getInitVal(); 5616 IV.setIsSigned(true); 5617 ECD->setInitVal(IV); 5618 5619 if (getLangOptions().CPlusPlus) 5620 // C++ [dcl.enum]p4: Following the closing brace of an 5621 // enum-specifier, each enumerator has the type of its 5622 // enumeration. 5623 ECD->setType(EnumType); 5624 continue; // Already int type. 5625 } 5626 5627 // Determine whether the value fits into an int. 5628 llvm::APSInt InitVal = ECD->getInitVal(); 5629 bool FitsInInt; 5630 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5631 FitsInInt = InitVal.getActiveBits() < IntWidth; 5632 else 5633 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5634 5635 // If it fits into an integer type, force it. Otherwise force it to match 5636 // the enum decl type. 5637 QualType NewTy; 5638 unsigned NewWidth; 5639 bool NewSign; 5640 if (FitsInInt) { 5641 NewTy = Context.IntTy; 5642 NewWidth = IntWidth; 5643 NewSign = true; 5644 } else if (ECD->getType() == BestType) { 5645 // Already the right type! 5646 if (getLangOptions().CPlusPlus) 5647 // C++ [dcl.enum]p4: Following the closing brace of an 5648 // enum-specifier, each enumerator has the type of its 5649 // enumeration. 5650 ECD->setType(EnumType); 5651 continue; 5652 } else { 5653 NewTy = BestType; 5654 NewWidth = BestWidth; 5655 NewSign = BestType->isSignedIntegerType(); 5656 } 5657 5658 // Adjust the APSInt value. 5659 InitVal.extOrTrunc(NewWidth); 5660 InitVal.setIsSigned(NewSign); 5661 ECD->setInitVal(InitVal); 5662 5663 // Adjust the Expr initializer and type. 5664 if (ECD->getInitExpr()) 5665 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5666 CastExpr::CK_IntegralCast, 5667 ECD->getInitExpr(), 5668 /*isLvalue=*/false)); 5669 if (getLangOptions().CPlusPlus) 5670 // C++ [dcl.enum]p4: Following the closing brace of an 5671 // enum-specifier, each enumerator has the type of its 5672 // enumeration. 5673 ECD->setType(EnumType); 5674 else 5675 ECD->setType(NewTy); 5676 } 5677 5678 Enum->completeDefinition(Context, BestType); 5679} 5680 5681Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5682 ExprArg expr) { 5683 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5684 5685 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5686 Loc, AsmString); 5687 CurContext->addDecl(New); 5688 return DeclPtrTy::make(New); 5689} 5690 5691void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5692 SourceLocation PragmaLoc, 5693 SourceLocation NameLoc) { 5694 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5695 5696 if (PrevDecl) { 5697 PrevDecl->addAttr(::new (Context) WeakAttr()); 5698 } else { 5699 (void)WeakUndeclaredIdentifiers.insert( 5700 std::pair<IdentifierInfo*,WeakInfo> 5701 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5702 } 5703} 5704 5705void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5706 IdentifierInfo* AliasName, 5707 SourceLocation PragmaLoc, 5708 SourceLocation NameLoc, 5709 SourceLocation AliasNameLoc) { 5710 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5711 WeakInfo W = WeakInfo(Name, NameLoc); 5712 5713 if (PrevDecl) { 5714 if (!PrevDecl->hasAttr<AliasAttr>()) 5715 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5716 DeclApplyPragmaWeak(TUScope, ND, W); 5717 } else { 5718 (void)WeakUndeclaredIdentifiers.insert( 5719 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5720 } 5721} 5722