SemaDecl.cpp revision 99a000e3ca7224cd70a2e87cc2751d78595c97f5
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/Analysis/CFG.h" 19#include "clang/AST/CXXInheritance.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Parse/ParseDiagnostic.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/BitVector.h" 34#include "llvm/ADT/STLExtras.h" 35#include <algorithm> 36#include <cstring> 37#include <functional> 38#include <queue> 39using namespace clang; 40 41/// getDeclName - Return a pretty name for the specified decl if possible, or 42/// an empty string if not. This is used for pretty crash reporting. 43std::string Sema::getDeclName(DeclPtrTy d) { 44 Decl *D = d.getAs<Decl>(); 45 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 46 return DN->getQualifiedNameAsString(); 47 return ""; 48} 49 50Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 51 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 52} 53 54/// \brief If the identifier refers to a type name within this scope, 55/// return the declaration of that type. 56/// 57/// This routine performs ordinary name lookup of the identifier II 58/// within the given scope, with optional C++ scope specifier SS, to 59/// determine whether the name refers to a type. If so, returns an 60/// opaque pointer (actually a QualType) corresponding to that 61/// type. Otherwise, returns NULL. 62/// 63/// If name lookup results in an ambiguity, this routine will complain 64/// and then return NULL. 65Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 66 Scope *S, const CXXScopeSpec *SS, 67 bool isClassName) { 68 // C++ [temp.res]p3: 69 // A qualified-id that refers to a type and in which the 70 // nested-name-specifier depends on a template-parameter (14.6.2) 71 // shall be prefixed by the keyword typename to indicate that the 72 // qualified-id denotes a type, forming an 73 // elaborated-type-specifier (7.1.5.3). 74 // 75 // We therefore do not perform any name lookup if the result would 76 // refer to a member of an unknown specialization. 77 if (SS && isUnknownSpecialization(*SS)) { 78 if (!isClassName) 79 return 0; 80 81 // We know from the grammar that this name refers to a type, so build a 82 // TypenameType node to describe the type. 83 // FIXME: Record somewhere that this TypenameType node has no "typename" 84 // keyword associated with it. 85 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 86 II, SS->getRange()).getAsOpaquePtr(); 87 } 88 89 LookupResult Result; 90 LookupParsedName(Result, S, SS, &II, LookupOrdinaryName, false, false); 91 92 NamedDecl *IIDecl = 0; 93 switch (Result.getKind()) { 94 case LookupResult::NotFound: 95 case LookupResult::FoundOverloaded: 96 return 0; 97 98 case LookupResult::Ambiguous: 99 // Recover from type-hiding ambiguities by hiding the type. We'll 100 // do the lookup again when looking for an object, and we can 101 // diagnose the error then. If we don't do this, then the error 102 // about hiding the type will be immediately followed by an error 103 // that only makes sense if the identifier was treated like a type. 104 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) 105 return 0; 106 107 // Look to see if we have a type anywhere in the list of results. 108 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 109 Res != ResEnd; ++Res) { 110 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 111 if (!IIDecl || 112 (*Res)->getLocation().getRawEncoding() < 113 IIDecl->getLocation().getRawEncoding()) 114 IIDecl = *Res; 115 } 116 } 117 118 if (!IIDecl) { 119 // None of the entities we found is a type, so there is no way 120 // to even assume that the result is a type. In this case, don't 121 // complain about the ambiguity. The parser will either try to 122 // perform this lookup again (e.g., as an object name), which 123 // will produce the ambiguity, or will complain that it expected 124 // a type name. 125 return 0; 126 } 127 128 // We found a type within the ambiguous lookup; diagnose the 129 // ambiguity and then return that type. This might be the right 130 // answer, or it might not be, but it suppresses any attempt to 131 // perform the name lookup again. 132 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 133 break; 134 135 case LookupResult::Found: 136 IIDecl = Result.getFoundDecl(); 137 break; 138 } 139 140 assert(IIDecl && "Didn't find decl"); 141 142 QualType T; 143 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 144 DiagnoseUseOfDecl(IIDecl, NameLoc); 145 146 // C++ [temp.local]p2: 147 // Within the scope of a class template specialization or 148 // partial specialization, when the injected-class-name is 149 // not followed by a <, it is equivalent to the 150 // injected-class-name followed by the template-argument s 151 // of the class template specialization or partial 152 // specialization enclosed in <>. 153 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 154 if (RD->isInjectedClassName()) 155 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 156 T = Template->getInjectedClassNameType(Context); 157 158 if (T.isNull()) 159 T = Context.getTypeDeclType(TD); 160 161 if (SS) 162 T = getQualifiedNameType(*SS, T); 163 164 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 165 DiagnoseUseOfDecl(IIDecl, NameLoc); 166 T = Context.getObjCInterfaceType(IDecl); 167 } else 168 return 0; 169 170 return T.getAsOpaquePtr(); 171} 172 173/// isTagName() - This method is called *for error recovery purposes only* 174/// to determine if the specified name is a valid tag name ("struct foo"). If 175/// so, this returns the TST for the tag corresponding to it (TST_enum, 176/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 177/// where the user forgot to specify the tag. 178DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 179 // Do a tag name lookup in this scope. 180 LookupResult R; 181 LookupName(R, S, &II, LookupTagName, false, false); 182 if (R.getKind() == LookupResult::Found) 183 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 184 switch (TD->getTagKind()) { 185 case TagDecl::TK_struct: return DeclSpec::TST_struct; 186 case TagDecl::TK_union: return DeclSpec::TST_union; 187 case TagDecl::TK_class: return DeclSpec::TST_class; 188 case TagDecl::TK_enum: return DeclSpec::TST_enum; 189 } 190 } 191 192 return DeclSpec::TST_unspecified; 193} 194 195bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 196 SourceLocation IILoc, 197 Scope *S, 198 const CXXScopeSpec *SS, 199 TypeTy *&SuggestedType) { 200 // We don't have anything to suggest (yet). 201 SuggestedType = 0; 202 203 // FIXME: Should we move the logic that tries to recover from a missing tag 204 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 205 206 if (!SS) 207 Diag(IILoc, diag::err_unknown_typename) << &II; 208 else if (DeclContext *DC = computeDeclContext(*SS, false)) 209 Diag(IILoc, diag::err_typename_nested_not_found) 210 << &II << DC << SS->getRange(); 211 else if (isDependentScopeSpecifier(*SS)) { 212 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 213 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 214 << SourceRange(SS->getRange().getBegin(), IILoc) 215 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 216 "typename "); 217 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 218 } else { 219 assert(SS && SS->isInvalid() && 220 "Invalid scope specifier has already been diagnosed"); 221 } 222 223 return true; 224} 225 226// Determines the context to return to after temporarily entering a 227// context. This depends in an unnecessarily complicated way on the 228// exact ordering of callbacks from the parser. 229DeclContext *Sema::getContainingDC(DeclContext *DC) { 230 231 // Functions defined inline within classes aren't parsed until we've 232 // finished parsing the top-level class, so the top-level class is 233 // the context we'll need to return to. 234 if (isa<FunctionDecl>(DC)) { 235 DC = DC->getLexicalParent(); 236 237 // A function not defined within a class will always return to its 238 // lexical context. 239 if (!isa<CXXRecordDecl>(DC)) 240 return DC; 241 242 // A C++ inline method/friend is parsed *after* the topmost class 243 // it was declared in is fully parsed ("complete"); the topmost 244 // class is the context we need to return to. 245 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 246 DC = RD; 247 248 // Return the declaration context of the topmost class the inline method is 249 // declared in. 250 return DC; 251 } 252 253 if (isa<ObjCMethodDecl>(DC)) 254 return Context.getTranslationUnitDecl(); 255 256 return DC->getLexicalParent(); 257} 258 259void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 260 assert(getContainingDC(DC) == CurContext && 261 "The next DeclContext should be lexically contained in the current one."); 262 CurContext = DC; 263 S->setEntity(DC); 264} 265 266void Sema::PopDeclContext() { 267 assert(CurContext && "DeclContext imbalance!"); 268 269 CurContext = getContainingDC(CurContext); 270} 271 272/// EnterDeclaratorContext - Used when we must lookup names in the context 273/// of a declarator's nested name specifier. 274void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 275 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 276 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 277 CurContext = DC; 278 assert(CurContext && "No context?"); 279 S->setEntity(CurContext); 280} 281 282void Sema::ExitDeclaratorContext(Scope *S) { 283 S->setEntity(PreDeclaratorDC); 284 PreDeclaratorDC = 0; 285 286 // Reset CurContext to the nearest enclosing context. 287 while (!S->getEntity() && S->getParent()) 288 S = S->getParent(); 289 CurContext = static_cast<DeclContext*>(S->getEntity()); 290 assert(CurContext && "No context?"); 291} 292 293/// \brief Determine whether we allow overloading of the function 294/// PrevDecl with another declaration. 295/// 296/// This routine determines whether overloading is possible, not 297/// whether some new function is actually an overload. It will return 298/// true in C++ (where we can always provide overloads) or, as an 299/// extension, in C when the previous function is already an 300/// overloaded function declaration or has the "overloadable" 301/// attribute. 302static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 303 if (Context.getLangOptions().CPlusPlus) 304 return true; 305 306 if (isa<OverloadedFunctionDecl>(PrevDecl)) 307 return true; 308 309 return PrevDecl->getAttr<OverloadableAttr>() != 0; 310} 311 312/// Add this decl to the scope shadowed decl chains. 313void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 314 // Move up the scope chain until we find the nearest enclosing 315 // non-transparent context. The declaration will be introduced into this 316 // scope. 317 while (S->getEntity() && 318 ((DeclContext *)S->getEntity())->isTransparentContext()) 319 S = S->getParent(); 320 321 // Add scoped declarations into their context, so that they can be 322 // found later. Declarations without a context won't be inserted 323 // into any context. 324 if (AddToContext) 325 CurContext->addDecl(D); 326 327 // Out-of-line function and variable definitions should not be pushed into 328 // scope. 329 if ((isa<FunctionTemplateDecl>(D) && 330 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 331 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 332 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 333 return; 334 335 // If this replaces anything in the current scope, 336 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 337 IEnd = IdResolver.end(); 338 for (; I != IEnd; ++I) { 339 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 340 S->RemoveDecl(DeclPtrTy::make(*I)); 341 IdResolver.RemoveDecl(*I); 342 343 // Should only need to replace one decl. 344 break; 345 } 346 } 347 348 S->AddDecl(DeclPtrTy::make(D)); 349 IdResolver.AddDecl(D); 350} 351 352bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 353 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 354 // Look inside the overload set to determine if any of the declarations 355 // are in scope. (Possibly) build a new overload set containing only 356 // those declarations that are in scope. 357 OverloadedFunctionDecl *NewOvl = 0; 358 bool FoundInScope = false; 359 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 360 FEnd = Ovl->function_end(); 361 F != FEnd; ++F) { 362 NamedDecl *FD = F->get(); 363 if (!isDeclInScope(FD, Ctx, S)) { 364 if (!NewOvl && F != Ovl->function_begin()) { 365 NewOvl = OverloadedFunctionDecl::Create(Context, 366 F->get()->getDeclContext(), 367 F->get()->getDeclName()); 368 D = NewOvl; 369 for (OverloadedFunctionDecl::function_iterator 370 First = Ovl->function_begin(); 371 First != F; ++First) 372 NewOvl->addOverload(*First); 373 } 374 } else { 375 FoundInScope = true; 376 if (NewOvl) 377 NewOvl->addOverload(*F); 378 } 379 } 380 381 return FoundInScope; 382 } 383 384 return IdResolver.isDeclInScope(D, Ctx, Context, S); 385} 386 387static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 388 return (!D->isUsed() && !D->hasAttr<UnusedAttr>() && isa<VarDecl>(D) && 389 !isa<ParmVarDecl>(D) && !isa<ImplicitParamDecl>(D) && 390 D->getDeclContext()->isFunctionOrMethod()); 391} 392 393void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 394 if (S->decl_empty()) return; 395 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 396 "Scope shouldn't contain decls!"); 397 398 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 399 I != E; ++I) { 400 Decl *TmpD = (*I).getAs<Decl>(); 401 assert(TmpD && "This decl didn't get pushed??"); 402 403 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 404 NamedDecl *D = cast<NamedDecl>(TmpD); 405 406 if (!D->getDeclName()) continue; 407 408 // Diagnose unused variables in this scope. 409 if (ShouldDiagnoseUnusedDecl(D)) 410 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 411 412 // Remove this name from our lexical scope. 413 IdResolver.RemoveDecl(D); 414 } 415} 416 417/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 418/// return 0 if one not found. 419ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 420 // The third "scope" argument is 0 since we aren't enabling lazy built-in 421 // creation from this context. 422 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 423 424 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 425} 426 427/// getNonFieldDeclScope - Retrieves the innermost scope, starting 428/// from S, where a non-field would be declared. This routine copes 429/// with the difference between C and C++ scoping rules in structs and 430/// unions. For example, the following code is well-formed in C but 431/// ill-formed in C++: 432/// @code 433/// struct S6 { 434/// enum { BAR } e; 435/// }; 436/// 437/// void test_S6() { 438/// struct S6 a; 439/// a.e = BAR; 440/// } 441/// @endcode 442/// For the declaration of BAR, this routine will return a different 443/// scope. The scope S will be the scope of the unnamed enumeration 444/// within S6. In C++, this routine will return the scope associated 445/// with S6, because the enumeration's scope is a transparent 446/// context but structures can contain non-field names. In C, this 447/// routine will return the translation unit scope, since the 448/// enumeration's scope is a transparent context and structures cannot 449/// contain non-field names. 450Scope *Sema::getNonFieldDeclScope(Scope *S) { 451 while (((S->getFlags() & Scope::DeclScope) == 0) || 452 (S->getEntity() && 453 ((DeclContext *)S->getEntity())->isTransparentContext()) || 454 (S->isClassScope() && !getLangOptions().CPlusPlus)) 455 S = S->getParent(); 456 return S; 457} 458 459void Sema::InitBuiltinVaListType() { 460 if (!Context.getBuiltinVaListType().isNull()) 461 return; 462 463 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 464 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 465 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 466 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 467} 468 469/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 470/// file scope. lazily create a decl for it. ForRedeclaration is true 471/// if we're creating this built-in in anticipation of redeclaring the 472/// built-in. 473NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 474 Scope *S, bool ForRedeclaration, 475 SourceLocation Loc) { 476 Builtin::ID BID = (Builtin::ID)bid; 477 478 if (Context.BuiltinInfo.hasVAListUse(BID)) 479 InitBuiltinVaListType(); 480 481 ASTContext::GetBuiltinTypeError Error; 482 QualType R = Context.GetBuiltinType(BID, Error); 483 switch (Error) { 484 case ASTContext::GE_None: 485 // Okay 486 break; 487 488 case ASTContext::GE_Missing_stdio: 489 if (ForRedeclaration) 490 Diag(Loc, diag::err_implicit_decl_requires_stdio) 491 << Context.BuiltinInfo.GetName(BID); 492 return 0; 493 494 case ASTContext::GE_Missing_setjmp: 495 if (ForRedeclaration) 496 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 497 << Context.BuiltinInfo.GetName(BID); 498 return 0; 499 } 500 501 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 502 Diag(Loc, diag::ext_implicit_lib_function_decl) 503 << Context.BuiltinInfo.GetName(BID) 504 << R; 505 if (Context.BuiltinInfo.getHeaderName(BID) && 506 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 507 != Diagnostic::Ignored) 508 Diag(Loc, diag::note_please_include_header) 509 << Context.BuiltinInfo.getHeaderName(BID) 510 << Context.BuiltinInfo.GetName(BID); 511 } 512 513 FunctionDecl *New = FunctionDecl::Create(Context, 514 Context.getTranslationUnitDecl(), 515 Loc, II, R, /*DInfo=*/0, 516 FunctionDecl::Extern, false, 517 /*hasPrototype=*/true); 518 New->setImplicit(); 519 520 // Create Decl objects for each parameter, adding them to the 521 // FunctionDecl. 522 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 523 llvm::SmallVector<ParmVarDecl*, 16> Params; 524 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 525 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 526 FT->getArgType(i), /*DInfo=*/0, 527 VarDecl::None, 0)); 528 New->setParams(Context, Params.data(), Params.size()); 529 } 530 531 AddKnownFunctionAttributes(New); 532 533 // TUScope is the translation-unit scope to insert this function into. 534 // FIXME: This is hideous. We need to teach PushOnScopeChains to 535 // relate Scopes to DeclContexts, and probably eliminate CurContext 536 // entirely, but we're not there yet. 537 DeclContext *SavedContext = CurContext; 538 CurContext = Context.getTranslationUnitDecl(); 539 PushOnScopeChains(New, TUScope); 540 CurContext = SavedContext; 541 return New; 542} 543 544/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 545/// same name and scope as a previous declaration 'Old'. Figure out 546/// how to resolve this situation, merging decls or emitting 547/// diagnostics as appropriate. If there was an error, set New to be invalid. 548/// 549void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 550 // If either decl is known invalid already, set the new one to be invalid and 551 // don't bother doing any merging checks. 552 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 553 return New->setInvalidDecl(); 554 555 // Allow multiple definitions for ObjC built-in typedefs. 556 // FIXME: Verify the underlying types are equivalent! 557 if (getLangOptions().ObjC1) { 558 const IdentifierInfo *TypeID = New->getIdentifier(); 559 switch (TypeID->getLength()) { 560 default: break; 561 case 2: 562 if (!TypeID->isStr("id")) 563 break; 564 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 565 // Install the built-in type for 'id', ignoring the current definition. 566 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 567 return; 568 case 5: 569 if (!TypeID->isStr("Class")) 570 break; 571 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 572 // Install the built-in type for 'Class', ignoring the current definition. 573 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 574 return; 575 case 3: 576 if (!TypeID->isStr("SEL")) 577 break; 578 Context.setObjCSelType(Context.getTypeDeclType(New)); 579 return; 580 case 8: 581 if (!TypeID->isStr("Protocol")) 582 break; 583 Context.setObjCProtoType(New->getUnderlyingType()); 584 return; 585 } 586 // Fall through - the typedef name was not a builtin type. 587 } 588 // Verify the old decl was also a type. 589 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 590 if (!Old) { 591 Diag(New->getLocation(), diag::err_redefinition_different_kind) 592 << New->getDeclName(); 593 if (OldD->getLocation().isValid()) 594 Diag(OldD->getLocation(), diag::note_previous_definition); 595 return New->setInvalidDecl(); 596 } 597 598 // Determine the "old" type we'll use for checking and diagnostics. 599 QualType OldType; 600 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 601 OldType = OldTypedef->getUnderlyingType(); 602 else 603 OldType = Context.getTypeDeclType(Old); 604 605 // If the typedef types are not identical, reject them in all languages and 606 // with any extensions enabled. 607 608 if (OldType != New->getUnderlyingType() && 609 Context.getCanonicalType(OldType) != 610 Context.getCanonicalType(New->getUnderlyingType())) { 611 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 612 << New->getUnderlyingType() << OldType; 613 if (Old->getLocation().isValid()) 614 Diag(Old->getLocation(), diag::note_previous_definition); 615 return New->setInvalidDecl(); 616 } 617 618 if (getLangOptions().Microsoft) 619 return; 620 621 // C++ [dcl.typedef]p2: 622 // In a given non-class scope, a typedef specifier can be used to 623 // redefine the name of any type declared in that scope to refer 624 // to the type to which it already refers. 625 if (getLangOptions().CPlusPlus) { 626 if (!isa<CXXRecordDecl>(CurContext)) 627 return; 628 Diag(New->getLocation(), diag::err_redefinition) 629 << New->getDeclName(); 630 Diag(Old->getLocation(), diag::note_previous_definition); 631 return New->setInvalidDecl(); 632 } 633 634 // If we have a redefinition of a typedef in C, emit a warning. This warning 635 // is normally mapped to an error, but can be controlled with 636 // -Wtypedef-redefinition. If either the original or the redefinition is 637 // in a system header, don't emit this for compatibility with GCC. 638 if (PP.getDiagnostics().getSuppressSystemWarnings() && 639 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 640 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 641 return; 642 643 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 644 << New->getDeclName(); 645 Diag(Old->getLocation(), diag::note_previous_definition); 646 return; 647} 648 649/// DeclhasAttr - returns true if decl Declaration already has the target 650/// attribute. 651static bool 652DeclHasAttr(const Decl *decl, const Attr *target) { 653 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 654 if (attr->getKind() == target->getKind()) 655 return true; 656 657 return false; 658} 659 660/// MergeAttributes - append attributes from the Old decl to the New one. 661static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 662 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 663 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 664 Attr *NewAttr = attr->clone(C); 665 NewAttr->setInherited(true); 666 New->addAttr(NewAttr); 667 } 668 } 669} 670 671/// Used in MergeFunctionDecl to keep track of function parameters in 672/// C. 673struct GNUCompatibleParamWarning { 674 ParmVarDecl *OldParm; 675 ParmVarDecl *NewParm; 676 QualType PromotedType; 677}; 678 679/// MergeFunctionDecl - We just parsed a function 'New' from 680/// declarator D which has the same name and scope as a previous 681/// declaration 'Old'. Figure out how to resolve this situation, 682/// merging decls or emitting diagnostics as appropriate. 683/// 684/// In C++, New and Old must be declarations that are not 685/// overloaded. Use IsOverload to determine whether New and Old are 686/// overloaded, and to select the Old declaration that New should be 687/// merged with. 688/// 689/// Returns true if there was an error, false otherwise. 690bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 691 assert(!isa<OverloadedFunctionDecl>(OldD) && 692 "Cannot merge with an overloaded function declaration"); 693 694 // Verify the old decl was also a function. 695 FunctionDecl *Old = 0; 696 if (FunctionTemplateDecl *OldFunctionTemplate 697 = dyn_cast<FunctionTemplateDecl>(OldD)) 698 Old = OldFunctionTemplate->getTemplatedDecl(); 699 else 700 Old = dyn_cast<FunctionDecl>(OldD); 701 if (!Old) { 702 Diag(New->getLocation(), diag::err_redefinition_different_kind) 703 << New->getDeclName(); 704 Diag(OldD->getLocation(), diag::note_previous_definition); 705 return true; 706 } 707 708 // Determine whether the previous declaration was a definition, 709 // implicit declaration, or a declaration. 710 diag::kind PrevDiag; 711 if (Old->isThisDeclarationADefinition()) 712 PrevDiag = diag::note_previous_definition; 713 else if (Old->isImplicit()) 714 PrevDiag = diag::note_previous_implicit_declaration; 715 else 716 PrevDiag = diag::note_previous_declaration; 717 718 QualType OldQType = Context.getCanonicalType(Old->getType()); 719 QualType NewQType = Context.getCanonicalType(New->getType()); 720 721 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 722 New->getStorageClass() == FunctionDecl::Static && 723 Old->getStorageClass() != FunctionDecl::Static) { 724 Diag(New->getLocation(), diag::err_static_non_static) 725 << New; 726 Diag(Old->getLocation(), PrevDiag); 727 return true; 728 } 729 730 if (getLangOptions().CPlusPlus) { 731 // (C++98 13.1p2): 732 // Certain function declarations cannot be overloaded: 733 // -- Function declarations that differ only in the return type 734 // cannot be overloaded. 735 QualType OldReturnType 736 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 737 QualType NewReturnType 738 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 739 if (OldReturnType != NewReturnType) { 740 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 741 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 742 return true; 743 } 744 745 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 746 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 747 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 748 NewMethod->getLexicalDeclContext()->isRecord()) { 749 // -- Member function declarations with the same name and the 750 // same parameter types cannot be overloaded if any of them 751 // is a static member function declaration. 752 if (OldMethod->isStatic() || NewMethod->isStatic()) { 753 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 754 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 755 return true; 756 } 757 758 // C++ [class.mem]p1: 759 // [...] A member shall not be declared twice in the 760 // member-specification, except that a nested class or member 761 // class template can be declared and then later defined. 762 unsigned NewDiag; 763 if (isa<CXXConstructorDecl>(OldMethod)) 764 NewDiag = diag::err_constructor_redeclared; 765 else if (isa<CXXDestructorDecl>(NewMethod)) 766 NewDiag = diag::err_destructor_redeclared; 767 else if (isa<CXXConversionDecl>(NewMethod)) 768 NewDiag = diag::err_conv_function_redeclared; 769 else 770 NewDiag = diag::err_member_redeclared; 771 772 Diag(New->getLocation(), NewDiag); 773 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 774 } 775 776 // (C++98 8.3.5p3): 777 // All declarations for a function shall agree exactly in both the 778 // return type and the parameter-type-list. 779 if (OldQType == NewQType) 780 return MergeCompatibleFunctionDecls(New, Old); 781 782 // Fall through for conflicting redeclarations and redefinitions. 783 } 784 785 // C: Function types need to be compatible, not identical. This handles 786 // duplicate function decls like "void f(int); void f(enum X);" properly. 787 if (!getLangOptions().CPlusPlus && 788 Context.typesAreCompatible(OldQType, NewQType)) { 789 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 790 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 791 const FunctionProtoType *OldProto = 0; 792 if (isa<FunctionNoProtoType>(NewFuncType) && 793 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 794 // The old declaration provided a function prototype, but the 795 // new declaration does not. Merge in the prototype. 796 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 797 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 798 OldProto->arg_type_end()); 799 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 800 ParamTypes.data(), ParamTypes.size(), 801 OldProto->isVariadic(), 802 OldProto->getTypeQuals()); 803 New->setType(NewQType); 804 New->setHasInheritedPrototype(); 805 806 // Synthesize a parameter for each argument type. 807 llvm::SmallVector<ParmVarDecl*, 16> Params; 808 for (FunctionProtoType::arg_type_iterator 809 ParamType = OldProto->arg_type_begin(), 810 ParamEnd = OldProto->arg_type_end(); 811 ParamType != ParamEnd; ++ParamType) { 812 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 813 SourceLocation(), 0, 814 *ParamType, /*DInfo=*/0, 815 VarDecl::None, 0); 816 Param->setImplicit(); 817 Params.push_back(Param); 818 } 819 820 New->setParams(Context, Params.data(), Params.size()); 821 } 822 823 return MergeCompatibleFunctionDecls(New, Old); 824 } 825 826 // GNU C permits a K&R definition to follow a prototype declaration 827 // if the declared types of the parameters in the K&R definition 828 // match the types in the prototype declaration, even when the 829 // promoted types of the parameters from the K&R definition differ 830 // from the types in the prototype. GCC then keeps the types from 831 // the prototype. 832 // 833 // If a variadic prototype is followed by a non-variadic K&R definition, 834 // the K&R definition becomes variadic. This is sort of an edge case, but 835 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 836 // C99 6.9.1p8. 837 if (!getLangOptions().CPlusPlus && 838 Old->hasPrototype() && !New->hasPrototype() && 839 New->getType()->getAs<FunctionProtoType>() && 840 Old->getNumParams() == New->getNumParams()) { 841 llvm::SmallVector<QualType, 16> ArgTypes; 842 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 843 const FunctionProtoType *OldProto 844 = Old->getType()->getAs<FunctionProtoType>(); 845 const FunctionProtoType *NewProto 846 = New->getType()->getAs<FunctionProtoType>(); 847 848 // Determine whether this is the GNU C extension. 849 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 850 NewProto->getResultType()); 851 bool LooseCompatible = !MergedReturn.isNull(); 852 for (unsigned Idx = 0, End = Old->getNumParams(); 853 LooseCompatible && Idx != End; ++Idx) { 854 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 855 ParmVarDecl *NewParm = New->getParamDecl(Idx); 856 if (Context.typesAreCompatible(OldParm->getType(), 857 NewProto->getArgType(Idx))) { 858 ArgTypes.push_back(NewParm->getType()); 859 } else if (Context.typesAreCompatible(OldParm->getType(), 860 NewParm->getType())) { 861 GNUCompatibleParamWarning Warn 862 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 863 Warnings.push_back(Warn); 864 ArgTypes.push_back(NewParm->getType()); 865 } else 866 LooseCompatible = false; 867 } 868 869 if (LooseCompatible) { 870 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 871 Diag(Warnings[Warn].NewParm->getLocation(), 872 diag::ext_param_promoted_not_compatible_with_prototype) 873 << Warnings[Warn].PromotedType 874 << Warnings[Warn].OldParm->getType(); 875 Diag(Warnings[Warn].OldParm->getLocation(), 876 diag::note_previous_declaration); 877 } 878 879 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 880 ArgTypes.size(), 881 OldProto->isVariadic(), 0)); 882 return MergeCompatibleFunctionDecls(New, Old); 883 } 884 885 // Fall through to diagnose conflicting types. 886 } 887 888 // A function that has already been declared has been redeclared or defined 889 // with a different type- show appropriate diagnostic 890 if (unsigned BuiltinID = Old->getBuiltinID()) { 891 // The user has declared a builtin function with an incompatible 892 // signature. 893 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 894 // The function the user is redeclaring is a library-defined 895 // function like 'malloc' or 'printf'. Warn about the 896 // redeclaration, then pretend that we don't know about this 897 // library built-in. 898 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 899 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 900 << Old << Old->getType(); 901 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 902 Old->setInvalidDecl(); 903 return false; 904 } 905 906 PrevDiag = diag::note_previous_builtin_declaration; 907 } 908 909 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 910 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 911 return true; 912} 913 914/// \brief Completes the merge of two function declarations that are 915/// known to be compatible. 916/// 917/// This routine handles the merging of attributes and other 918/// properties of function declarations form the old declaration to 919/// the new declaration, once we know that New is in fact a 920/// redeclaration of Old. 921/// 922/// \returns false 923bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 924 // Merge the attributes 925 MergeAttributes(New, Old, Context); 926 927 // Merge the storage class. 928 if (Old->getStorageClass() != FunctionDecl::Extern && 929 Old->getStorageClass() != FunctionDecl::None) 930 New->setStorageClass(Old->getStorageClass()); 931 932 // Merge "pure" flag. 933 if (Old->isPure()) 934 New->setPure(); 935 936 // Merge the "deleted" flag. 937 if (Old->isDeleted()) 938 New->setDeleted(); 939 940 if (getLangOptions().CPlusPlus) 941 return MergeCXXFunctionDecl(New, Old); 942 943 return false; 944} 945 946/// MergeVarDecl - We just parsed a variable 'New' which has the same name 947/// and scope as a previous declaration 'Old'. Figure out how to resolve this 948/// situation, merging decls or emitting diagnostics as appropriate. 949/// 950/// Tentative definition rules (C99 6.9.2p2) are checked by 951/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 952/// definitions here, since the initializer hasn't been attached. 953/// 954void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 955 // If either decl is invalid, make sure the new one is marked invalid and 956 // don't do any other checking. 957 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 958 return New->setInvalidDecl(); 959 960 // Verify the old decl was also a variable. 961 VarDecl *Old = dyn_cast<VarDecl>(OldD); 962 if (!Old) { 963 Diag(New->getLocation(), diag::err_redefinition_different_kind) 964 << New->getDeclName(); 965 Diag(OldD->getLocation(), diag::note_previous_definition); 966 return New->setInvalidDecl(); 967 } 968 969 MergeAttributes(New, Old, Context); 970 971 // Merge the types 972 QualType MergedT; 973 if (getLangOptions().CPlusPlus) { 974 if (Context.hasSameType(New->getType(), Old->getType())) 975 MergedT = New->getType(); 976 // C++ [basic.types]p7: 977 // [...] The declared type of an array object might be an array of 978 // unknown size and therefore be incomplete at one point in a 979 // translation unit and complete later on; [...] 980 else if (Old->getType()->isIncompleteArrayType() && 981 New->getType()->isArrayType()) { 982 CanQual<ArrayType> OldArray 983 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 984 CanQual<ArrayType> NewArray 985 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 986 if (OldArray->getElementType() == NewArray->getElementType()) 987 MergedT = New->getType(); 988 } 989 } else { 990 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 991 } 992 if (MergedT.isNull()) { 993 Diag(New->getLocation(), diag::err_redefinition_different_type) 994 << New->getDeclName(); 995 Diag(Old->getLocation(), diag::note_previous_definition); 996 return New->setInvalidDecl(); 997 } 998 New->setType(MergedT); 999 1000 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1001 if (New->getStorageClass() == VarDecl::Static && 1002 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1003 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1004 Diag(Old->getLocation(), diag::note_previous_definition); 1005 return New->setInvalidDecl(); 1006 } 1007 // C99 6.2.2p4: 1008 // For an identifier declared with the storage-class specifier 1009 // extern in a scope in which a prior declaration of that 1010 // identifier is visible,23) if the prior declaration specifies 1011 // internal or external linkage, the linkage of the identifier at 1012 // the later declaration is the same as the linkage specified at 1013 // the prior declaration. If no prior declaration is visible, or 1014 // if the prior declaration specifies no linkage, then the 1015 // identifier has external linkage. 1016 if (New->hasExternalStorage() && Old->hasLinkage()) 1017 /* Okay */; 1018 else if (New->getStorageClass() != VarDecl::Static && 1019 Old->getStorageClass() == VarDecl::Static) { 1020 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1021 Diag(Old->getLocation(), diag::note_previous_definition); 1022 return New->setInvalidDecl(); 1023 } 1024 1025 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1026 1027 // FIXME: The test for external storage here seems wrong? We still 1028 // need to check for mismatches. 1029 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1030 // Don't complain about out-of-line definitions of static members. 1031 !(Old->getLexicalDeclContext()->isRecord() && 1032 !New->getLexicalDeclContext()->isRecord())) { 1033 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1034 Diag(Old->getLocation(), diag::note_previous_definition); 1035 return New->setInvalidDecl(); 1036 } 1037 1038 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1039 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1040 Diag(Old->getLocation(), diag::note_previous_definition); 1041 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1042 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1043 Diag(Old->getLocation(), diag::note_previous_definition); 1044 } 1045 1046 // Keep a chain of previous declarations. 1047 New->setPreviousDeclaration(Old); 1048} 1049 1050/// CheckFallThrough - Check that we don't fall off the end of a 1051/// Statement that should return a value. 1052/// 1053/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1054/// MaybeFallThrough iff we might or might not fall off the end, 1055/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1056/// return. We assume NeverFallThrough iff we never fall off the end of the 1057/// statement but we may return. We assume that functions not marked noreturn 1058/// will return. 1059Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1060 // FIXME: Eventually share this CFG object when we have other warnings based 1061 // of the CFG. This can be done using AnalysisContext. 1062 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1063 1064 // FIXME: They should never return 0, fix that, delete this code. 1065 if (cfg == 0) 1066 // FIXME: This should be NeverFallThrough 1067 return NeverFallThroughOrReturn; 1068 // The CFG leaves in dead things, and we don't want to dead code paths to 1069 // confuse us, so we mark all live things first. 1070 std::queue<CFGBlock*> workq; 1071 llvm::BitVector live(cfg->getNumBlockIDs()); 1072 // Prep work queue 1073 workq.push(&cfg->getEntry()); 1074 // Solve 1075 while (!workq.empty()) { 1076 CFGBlock *item = workq.front(); 1077 workq.pop(); 1078 live.set(item->getBlockID()); 1079 for (CFGBlock::succ_iterator I=item->succ_begin(), 1080 E=item->succ_end(); 1081 I != E; 1082 ++I) { 1083 if ((*I) && !live[(*I)->getBlockID()]) { 1084 live.set((*I)->getBlockID()); 1085 workq.push(*I); 1086 } 1087 } 1088 } 1089 1090 // Now we know what is live, we check the live precessors of the exit block 1091 // and look for fall through paths, being careful to ignore normal returns, 1092 // and exceptional paths. 1093 bool HasLiveReturn = false; 1094 bool HasFakeEdge = false; 1095 bool HasPlainEdge = false; 1096 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1097 E = cfg->getExit().pred_end(); 1098 I != E; 1099 ++I) { 1100 CFGBlock& B = **I; 1101 if (!live[B.getBlockID()]) 1102 continue; 1103 if (B.size() == 0) { 1104 // A labeled empty statement, or the entry block... 1105 HasPlainEdge = true; 1106 continue; 1107 } 1108 Stmt *S = B[B.size()-1]; 1109 if (isa<ReturnStmt>(S)) { 1110 HasLiveReturn = true; 1111 continue; 1112 } 1113 if (isa<ObjCAtThrowStmt>(S)) { 1114 HasFakeEdge = true; 1115 continue; 1116 } 1117 if (isa<CXXThrowExpr>(S)) { 1118 HasFakeEdge = true; 1119 continue; 1120 } 1121 bool NoReturnEdge = false; 1122 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1123 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1124 if (CEE->getType().getNoReturnAttr()) { 1125 NoReturnEdge = true; 1126 HasFakeEdge = true; 1127 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1128 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1129 if (FD->hasAttr<NoReturnAttr>()) { 1130 NoReturnEdge = true; 1131 HasFakeEdge = true; 1132 } 1133 } 1134 } 1135 } 1136 // FIXME: Add noreturn message sends. 1137 if (NoReturnEdge == false) 1138 HasPlainEdge = true; 1139 } 1140 if (!HasPlainEdge) { 1141 if (HasLiveReturn) 1142 return NeverFallThrough; 1143 return NeverFallThroughOrReturn; 1144 } 1145 if (HasFakeEdge || HasLiveReturn) 1146 return MaybeFallThrough; 1147 // This says AlwaysFallThrough for calls to functions that are not marked 1148 // noreturn, that don't return. If people would like this warning to be more 1149 // accurate, such functions should be marked as noreturn. 1150 return AlwaysFallThrough; 1151} 1152 1153/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1154/// function that should return a value. Check that we don't fall off the end 1155/// of a noreturn function. We assume that functions and blocks not marked 1156/// noreturn will return. 1157void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1158 // FIXME: Would be nice if we had a better way to control cascading errors, 1159 // but for now, avoid them. The problem is that when Parse sees: 1160 // int foo() { return a; } 1161 // The return is eaten and the Sema code sees just: 1162 // int foo() { } 1163 // which this code would then warn about. 1164 if (getDiagnostics().hasErrorOccurred()) 1165 return; 1166 1167 bool ReturnsVoid = false; 1168 bool HasNoReturn = false; 1169 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1170 // If the result type of the function is a dependent type, we don't know 1171 // whether it will be void or not, so don't 1172 if (FD->getResultType()->isDependentType()) 1173 return; 1174 if (FD->getResultType()->isVoidType()) 1175 ReturnsVoid = true; 1176 if (FD->hasAttr<NoReturnAttr>()) 1177 HasNoReturn = true; 1178 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1179 if (MD->getResultType()->isVoidType()) 1180 ReturnsVoid = true; 1181 if (MD->hasAttr<NoReturnAttr>()) 1182 HasNoReturn = true; 1183 } 1184 1185 // Short circuit for compilation speed. 1186 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1187 == Diagnostic::Ignored || ReturnsVoid) 1188 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1189 == Diagnostic::Ignored || !HasNoReturn) 1190 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1191 == Diagnostic::Ignored || !ReturnsVoid)) 1192 return; 1193 // FIXME: Function try block 1194 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1195 switch (CheckFallThrough(Body)) { 1196 case MaybeFallThrough: 1197 if (HasNoReturn) 1198 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1199 else if (!ReturnsVoid) 1200 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1201 break; 1202 case AlwaysFallThrough: 1203 if (HasNoReturn) 1204 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1205 else if (!ReturnsVoid) 1206 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1207 break; 1208 case NeverFallThroughOrReturn: 1209 if (ReturnsVoid && !HasNoReturn) 1210 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1211 break; 1212 case NeverFallThrough: 1213 break; 1214 } 1215 } 1216} 1217 1218/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1219/// that should return a value. Check that we don't fall off the end of a 1220/// noreturn block. We assume that functions and blocks not marked noreturn 1221/// will return. 1222void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1223 // FIXME: Would be nice if we had a better way to control cascading errors, 1224 // but for now, avoid them. The problem is that when Parse sees: 1225 // int foo() { return a; } 1226 // The return is eaten and the Sema code sees just: 1227 // int foo() { } 1228 // which this code would then warn about. 1229 if (getDiagnostics().hasErrorOccurred()) 1230 return; 1231 bool ReturnsVoid = false; 1232 bool HasNoReturn = false; 1233 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1234 if (FT->getResultType()->isVoidType()) 1235 ReturnsVoid = true; 1236 if (FT->getNoReturnAttr()) 1237 HasNoReturn = true; 1238 } 1239 1240 // Short circuit for compilation speed. 1241 if (ReturnsVoid 1242 && !HasNoReturn 1243 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1244 == Diagnostic::Ignored || !ReturnsVoid)) 1245 return; 1246 // FIXME: Funtion try block 1247 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1248 switch (CheckFallThrough(Body)) { 1249 case MaybeFallThrough: 1250 if (HasNoReturn) 1251 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1252 else if (!ReturnsVoid) 1253 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1254 break; 1255 case AlwaysFallThrough: 1256 if (HasNoReturn) 1257 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1258 else if (!ReturnsVoid) 1259 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1260 break; 1261 case NeverFallThroughOrReturn: 1262 if (ReturnsVoid) 1263 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1264 break; 1265 case NeverFallThrough: 1266 break; 1267 } 1268 } 1269} 1270 1271/// CheckParmsForFunctionDef - Check that the parameters of the given 1272/// function are appropriate for the definition of a function. This 1273/// takes care of any checks that cannot be performed on the 1274/// declaration itself, e.g., that the types of each of the function 1275/// parameters are complete. 1276bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1277 bool HasInvalidParm = false; 1278 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1279 ParmVarDecl *Param = FD->getParamDecl(p); 1280 1281 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1282 // function declarator that is part of a function definition of 1283 // that function shall not have incomplete type. 1284 // 1285 // This is also C++ [dcl.fct]p6. 1286 if (!Param->isInvalidDecl() && 1287 RequireCompleteType(Param->getLocation(), Param->getType(), 1288 diag::err_typecheck_decl_incomplete_type)) { 1289 Param->setInvalidDecl(); 1290 HasInvalidParm = true; 1291 } 1292 1293 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1294 // declaration of each parameter shall include an identifier. 1295 if (Param->getIdentifier() == 0 && 1296 !Param->isImplicit() && 1297 !getLangOptions().CPlusPlus) 1298 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1299 } 1300 1301 return HasInvalidParm; 1302} 1303 1304/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1305/// no declarator (e.g. "struct foo;") is parsed. 1306Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1307 // FIXME: Error on auto/register at file scope 1308 // FIXME: Error on inline/virtual/explicit 1309 // FIXME: Error on invalid restrict 1310 // FIXME: Warn on useless __thread 1311 // FIXME: Warn on useless const/volatile 1312 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1313 // FIXME: Warn on useless attributes 1314 Decl *TagD = 0; 1315 TagDecl *Tag = 0; 1316 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1317 DS.getTypeSpecType() == DeclSpec::TST_struct || 1318 DS.getTypeSpecType() == DeclSpec::TST_union || 1319 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1320 TagD = static_cast<Decl *>(DS.getTypeRep()); 1321 1322 if (!TagD) // We probably had an error 1323 return DeclPtrTy(); 1324 1325 // Note that the above type specs guarantee that the 1326 // type rep is a Decl, whereas in many of the others 1327 // it's a Type. 1328 Tag = dyn_cast<TagDecl>(TagD); 1329 } 1330 1331 if (DS.isFriendSpecified()) { 1332 // If we're dealing with a class template decl, assume that the 1333 // template routines are handling it. 1334 if (TagD && isa<ClassTemplateDecl>(TagD)) 1335 return DeclPtrTy(); 1336 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1337 } 1338 1339 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1340 // If there are attributes in the DeclSpec, apply them to the record. 1341 if (const AttributeList *AL = DS.getAttributes()) 1342 ProcessDeclAttributeList(S, Record, AL); 1343 1344 if (!Record->getDeclName() && Record->isDefinition() && 1345 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1346 if (getLangOptions().CPlusPlus || 1347 Record->getDeclContext()->isRecord()) 1348 return BuildAnonymousStructOrUnion(S, DS, Record); 1349 1350 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1351 << DS.getSourceRange(); 1352 } 1353 1354 // Microsoft allows unnamed struct/union fields. Don't complain 1355 // about them. 1356 // FIXME: Should we support Microsoft's extensions in this area? 1357 if (Record->getDeclName() && getLangOptions().Microsoft) 1358 return DeclPtrTy::make(Tag); 1359 } 1360 1361 if (!DS.isMissingDeclaratorOk() && 1362 DS.getTypeSpecType() != DeclSpec::TST_error) { 1363 // Warn about typedefs of enums without names, since this is an 1364 // extension in both Microsoft an GNU. 1365 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1366 Tag && isa<EnumDecl>(Tag)) { 1367 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1368 << DS.getSourceRange(); 1369 return DeclPtrTy::make(Tag); 1370 } 1371 1372 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1373 << DS.getSourceRange(); 1374 return DeclPtrTy(); 1375 } 1376 1377 return DeclPtrTy::make(Tag); 1378} 1379 1380/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1381/// anonymous struct or union AnonRecord into the owning context Owner 1382/// and scope S. This routine will be invoked just after we realize 1383/// that an unnamed union or struct is actually an anonymous union or 1384/// struct, e.g., 1385/// 1386/// @code 1387/// union { 1388/// int i; 1389/// float f; 1390/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1391/// // f into the surrounding scope.x 1392/// @endcode 1393/// 1394/// This routine is recursive, injecting the names of nested anonymous 1395/// structs/unions into the owning context and scope as well. 1396bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1397 RecordDecl *AnonRecord) { 1398 bool Invalid = false; 1399 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1400 FEnd = AnonRecord->field_end(); 1401 F != FEnd; ++F) { 1402 if ((*F)->getDeclName()) { 1403 LookupResult R; 1404 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1405 LookupOrdinaryName, true); 1406 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1407 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1408 // C++ [class.union]p2: 1409 // The names of the members of an anonymous union shall be 1410 // distinct from the names of any other entity in the 1411 // scope in which the anonymous union is declared. 1412 unsigned diagKind 1413 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1414 : diag::err_anonymous_struct_member_redecl; 1415 Diag((*F)->getLocation(), diagKind) 1416 << (*F)->getDeclName(); 1417 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1418 Invalid = true; 1419 } else { 1420 // C++ [class.union]p2: 1421 // For the purpose of name lookup, after the anonymous union 1422 // definition, the members of the anonymous union are 1423 // considered to have been defined in the scope in which the 1424 // anonymous union is declared. 1425 Owner->makeDeclVisibleInContext(*F); 1426 S->AddDecl(DeclPtrTy::make(*F)); 1427 IdResolver.AddDecl(*F); 1428 } 1429 } else if (const RecordType *InnerRecordType 1430 = (*F)->getType()->getAs<RecordType>()) { 1431 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1432 if (InnerRecord->isAnonymousStructOrUnion()) 1433 Invalid = Invalid || 1434 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1435 } 1436 } 1437 1438 return Invalid; 1439} 1440 1441/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1442/// anonymous structure or union. Anonymous unions are a C++ feature 1443/// (C++ [class.union]) and a GNU C extension; anonymous structures 1444/// are a GNU C and GNU C++ extension. 1445Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1446 RecordDecl *Record) { 1447 DeclContext *Owner = Record->getDeclContext(); 1448 1449 // Diagnose whether this anonymous struct/union is an extension. 1450 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1451 Diag(Record->getLocation(), diag::ext_anonymous_union); 1452 else if (!Record->isUnion()) 1453 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1454 1455 // C and C++ require different kinds of checks for anonymous 1456 // structs/unions. 1457 bool Invalid = false; 1458 if (getLangOptions().CPlusPlus) { 1459 const char* PrevSpec = 0; 1460 unsigned DiagID; 1461 // C++ [class.union]p3: 1462 // Anonymous unions declared in a named namespace or in the 1463 // global namespace shall be declared static. 1464 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1465 (isa<TranslationUnitDecl>(Owner) || 1466 (isa<NamespaceDecl>(Owner) && 1467 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1468 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1469 Invalid = true; 1470 1471 // Recover by adding 'static'. 1472 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1473 PrevSpec, DiagID); 1474 } 1475 // C++ [class.union]p3: 1476 // A storage class is not allowed in a declaration of an 1477 // anonymous union in a class scope. 1478 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1479 isa<RecordDecl>(Owner)) { 1480 Diag(DS.getStorageClassSpecLoc(), 1481 diag::err_anonymous_union_with_storage_spec); 1482 Invalid = true; 1483 1484 // Recover by removing the storage specifier. 1485 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1486 PrevSpec, DiagID); 1487 } 1488 1489 // C++ [class.union]p2: 1490 // The member-specification of an anonymous union shall only 1491 // define non-static data members. [Note: nested types and 1492 // functions cannot be declared within an anonymous union. ] 1493 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1494 MemEnd = Record->decls_end(); 1495 Mem != MemEnd; ++Mem) { 1496 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1497 // C++ [class.union]p3: 1498 // An anonymous union shall not have private or protected 1499 // members (clause 11). 1500 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1501 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1502 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1503 Invalid = true; 1504 } 1505 } else if ((*Mem)->isImplicit()) { 1506 // Any implicit members are fine. 1507 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1508 // This is a type that showed up in an 1509 // elaborated-type-specifier inside the anonymous struct or 1510 // union, but which actually declares a type outside of the 1511 // anonymous struct or union. It's okay. 1512 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1513 if (!MemRecord->isAnonymousStructOrUnion() && 1514 MemRecord->getDeclName()) { 1515 // This is a nested type declaration. 1516 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1517 << (int)Record->isUnion(); 1518 Invalid = true; 1519 } 1520 } else { 1521 // We have something that isn't a non-static data 1522 // member. Complain about it. 1523 unsigned DK = diag::err_anonymous_record_bad_member; 1524 if (isa<TypeDecl>(*Mem)) 1525 DK = diag::err_anonymous_record_with_type; 1526 else if (isa<FunctionDecl>(*Mem)) 1527 DK = diag::err_anonymous_record_with_function; 1528 else if (isa<VarDecl>(*Mem)) 1529 DK = diag::err_anonymous_record_with_static; 1530 Diag((*Mem)->getLocation(), DK) 1531 << (int)Record->isUnion(); 1532 Invalid = true; 1533 } 1534 } 1535 } 1536 1537 if (!Record->isUnion() && !Owner->isRecord()) { 1538 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1539 << (int)getLangOptions().CPlusPlus; 1540 Invalid = true; 1541 } 1542 1543 // Mock up a declarator. 1544 Declarator Dc(DS, Declarator::TypeNameContext); 1545 DeclaratorInfo *DInfo = 0; 1546 GetTypeForDeclarator(Dc, S, &DInfo); 1547 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1548 1549 // Create a declaration for this anonymous struct/union. 1550 NamedDecl *Anon = 0; 1551 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1552 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1553 /*IdentifierInfo=*/0, 1554 Context.getTypeDeclType(Record), 1555 DInfo, 1556 /*BitWidth=*/0, /*Mutable=*/false); 1557 Anon->setAccess(AS_public); 1558 if (getLangOptions().CPlusPlus) 1559 FieldCollector->Add(cast<FieldDecl>(Anon)); 1560 } else { 1561 VarDecl::StorageClass SC; 1562 switch (DS.getStorageClassSpec()) { 1563 default: assert(0 && "Unknown storage class!"); 1564 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1565 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1566 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1567 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1568 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1569 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1570 case DeclSpec::SCS_mutable: 1571 // mutable can only appear on non-static class members, so it's always 1572 // an error here 1573 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1574 Invalid = true; 1575 SC = VarDecl::None; 1576 break; 1577 } 1578 1579 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1580 /*IdentifierInfo=*/0, 1581 Context.getTypeDeclType(Record), 1582 DInfo, 1583 SC); 1584 } 1585 Anon->setImplicit(); 1586 1587 // Add the anonymous struct/union object to the current 1588 // context. We'll be referencing this object when we refer to one of 1589 // its members. 1590 Owner->addDecl(Anon); 1591 1592 // Inject the members of the anonymous struct/union into the owning 1593 // context and into the identifier resolver chain for name lookup 1594 // purposes. 1595 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1596 Invalid = true; 1597 1598 // Mark this as an anonymous struct/union type. Note that we do not 1599 // do this until after we have already checked and injected the 1600 // members of this anonymous struct/union type, because otherwise 1601 // the members could be injected twice: once by DeclContext when it 1602 // builds its lookup table, and once by 1603 // InjectAnonymousStructOrUnionMembers. 1604 Record->setAnonymousStructOrUnion(true); 1605 1606 if (Invalid) 1607 Anon->setInvalidDecl(); 1608 1609 return DeclPtrTy::make(Anon); 1610} 1611 1612 1613/// GetNameForDeclarator - Determine the full declaration name for the 1614/// given Declarator. 1615DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1616 return GetNameFromUnqualifiedId(D.getName()); 1617} 1618 1619/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1620DeclarationName Sema::GetNameFromUnqualifiedId(UnqualifiedId &Name) { 1621 switch (Name.getKind()) { 1622 case UnqualifiedId::IK_Identifier: 1623 return DeclarationName(Name.Identifier); 1624 1625 case UnqualifiedId::IK_OperatorFunctionId: 1626 return Context.DeclarationNames.getCXXOperatorName( 1627 Name.OperatorFunctionId.Operator); 1628 1629 case UnqualifiedId::IK_ConversionFunctionId: { 1630 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1631 if (Ty.isNull()) 1632 return DeclarationName(); 1633 1634 return Context.DeclarationNames.getCXXConversionFunctionName( 1635 Context.getCanonicalType(Ty)); 1636 } 1637 1638 case UnqualifiedId::IK_ConstructorName: { 1639 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1640 if (Ty.isNull()) 1641 return DeclarationName(); 1642 1643 return Context.DeclarationNames.getCXXConstructorName( 1644 Context.getCanonicalType(Ty)); 1645 } 1646 1647 case UnqualifiedId::IK_DestructorName: { 1648 QualType Ty = GetTypeFromParser(Name.DestructorName); 1649 if (Ty.isNull()) 1650 return DeclarationName(); 1651 1652 return Context.DeclarationNames.getCXXDestructorName( 1653 Context.getCanonicalType(Ty)); 1654 } 1655 1656 case UnqualifiedId::IK_TemplateId: { 1657 TemplateName TName 1658 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1659 if (TemplateDecl *Template = TName.getAsTemplateDecl()) 1660 return Template->getDeclName(); 1661 if (OverloadedFunctionDecl *Ovl = TName.getAsOverloadedFunctionDecl()) 1662 return Ovl->getDeclName(); 1663 1664 return DeclarationName(); 1665 } 1666 } 1667 1668 assert(false && "Unknown name kind"); 1669 return DeclarationName(); 1670} 1671 1672/// isNearlyMatchingFunction - Determine whether the C++ functions 1673/// Declaration and Definition are "nearly" matching. This heuristic 1674/// is used to improve diagnostics in the case where an out-of-line 1675/// function definition doesn't match any declaration within 1676/// the class or namespace. 1677static bool isNearlyMatchingFunction(ASTContext &Context, 1678 FunctionDecl *Declaration, 1679 FunctionDecl *Definition) { 1680 if (Declaration->param_size() != Definition->param_size()) 1681 return false; 1682 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1683 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1684 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1685 1686 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1687 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1688 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1689 return false; 1690 } 1691 1692 return true; 1693} 1694 1695Sema::DeclPtrTy 1696Sema::HandleDeclarator(Scope *S, Declarator &D, 1697 MultiTemplateParamsArg TemplateParamLists, 1698 bool IsFunctionDefinition) { 1699 DeclarationName Name = GetNameForDeclarator(D); 1700 1701 // All of these full declarators require an identifier. If it doesn't have 1702 // one, the ParsedFreeStandingDeclSpec action should be used. 1703 if (!Name) { 1704 if (!D.isInvalidType()) // Reject this if we think it is valid. 1705 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1706 diag::err_declarator_need_ident) 1707 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1708 return DeclPtrTy(); 1709 } 1710 1711 // The scope passed in may not be a decl scope. Zip up the scope tree until 1712 // we find one that is. 1713 while ((S->getFlags() & Scope::DeclScope) == 0 || 1714 (S->getFlags() & Scope::TemplateParamScope) != 0) 1715 S = S->getParent(); 1716 1717 // If this is an out-of-line definition of a member of a class template 1718 // or class template partial specialization, we may need to rebuild the 1719 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1720 // for more information. 1721 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1722 // handle expressions properly. 1723 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1724 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1725 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1726 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1727 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1728 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1729 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1730 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1731 // FIXME: Preserve type source info. 1732 QualType T = GetTypeFromParser(DS.getTypeRep()); 1733 EnterDeclaratorContext(S, DC); 1734 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1735 ExitDeclaratorContext(S); 1736 if (T.isNull()) 1737 return DeclPtrTy(); 1738 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1739 } 1740 } 1741 1742 DeclContext *DC; 1743 NamedDecl *PrevDecl; 1744 NamedDecl *New; 1745 1746 DeclaratorInfo *DInfo = 0; 1747 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1748 1749 // See if this is a redefinition of a variable in the same scope. 1750 if (D.getCXXScopeSpec().isInvalid()) { 1751 DC = CurContext; 1752 PrevDecl = 0; 1753 D.setInvalidType(); 1754 } else if (!D.getCXXScopeSpec().isSet()) { 1755 LookupNameKind NameKind = LookupOrdinaryName; 1756 1757 // If the declaration we're planning to build will be a function 1758 // or object with linkage, then look for another declaration with 1759 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1760 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1761 /* Do nothing*/; 1762 else if (R->isFunctionType()) { 1763 if (CurContext->isFunctionOrMethod() || 1764 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1765 NameKind = LookupRedeclarationWithLinkage; 1766 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1767 NameKind = LookupRedeclarationWithLinkage; 1768 else if (CurContext->getLookupContext()->isTranslationUnit() && 1769 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1770 NameKind = LookupRedeclarationWithLinkage; 1771 1772 DC = CurContext; 1773 LookupResult R; 1774 LookupName(R, S, Name, NameKind, true, 1775 NameKind == LookupRedeclarationWithLinkage, 1776 D.getIdentifierLoc()); 1777 PrevDecl = R.getAsSingleDecl(Context); 1778 } else { // Something like "int foo::x;" 1779 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1780 1781 if (!DC) { 1782 // If we could not compute the declaration context, it's because the 1783 // declaration context is dependent but does not refer to a class, 1784 // class template, or class template partial specialization. Complain 1785 // and return early, to avoid the coming semantic disaster. 1786 Diag(D.getIdentifierLoc(), 1787 diag::err_template_qualified_declarator_no_match) 1788 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1789 << D.getCXXScopeSpec().getRange(); 1790 return DeclPtrTy(); 1791 } 1792 1793 if (!DC->isDependentContext() && 1794 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1795 return DeclPtrTy(); 1796 1797 LookupResult Res; 1798 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1799 PrevDecl = Res.getAsSingleDecl(Context); 1800 1801 // C++ 7.3.1.2p2: 1802 // Members (including explicit specializations of templates) of a named 1803 // namespace can also be defined outside that namespace by explicit 1804 // qualification of the name being defined, provided that the entity being 1805 // defined was already declared in the namespace and the definition appears 1806 // after the point of declaration in a namespace that encloses the 1807 // declarations namespace. 1808 // 1809 // Note that we only check the context at this point. We don't yet 1810 // have enough information to make sure that PrevDecl is actually 1811 // the declaration we want to match. For example, given: 1812 // 1813 // class X { 1814 // void f(); 1815 // void f(float); 1816 // }; 1817 // 1818 // void X::f(int) { } // ill-formed 1819 // 1820 // In this case, PrevDecl will point to the overload set 1821 // containing the two f's declared in X, but neither of them 1822 // matches. 1823 1824 // First check whether we named the global scope. 1825 if (isa<TranslationUnitDecl>(DC)) { 1826 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1827 << Name << D.getCXXScopeSpec().getRange(); 1828 } else if (!CurContext->Encloses(DC)) { 1829 // The qualifying scope doesn't enclose the original declaration. 1830 // Emit diagnostic based on current scope. 1831 SourceLocation L = D.getIdentifierLoc(); 1832 SourceRange R = D.getCXXScopeSpec().getRange(); 1833 if (isa<FunctionDecl>(CurContext)) 1834 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1835 else 1836 Diag(L, diag::err_invalid_declarator_scope) 1837 << Name << cast<NamedDecl>(DC) << R; 1838 D.setInvalidType(); 1839 } 1840 } 1841 1842 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1843 // Maybe we will complain about the shadowed template parameter. 1844 if (!D.isInvalidType()) 1845 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1846 D.setInvalidType(); 1847 1848 // Just pretend that we didn't see the previous declaration. 1849 PrevDecl = 0; 1850 } 1851 1852 // In C++, the previous declaration we find might be a tag type 1853 // (class or enum). In this case, the new declaration will hide the 1854 // tag type. Note that this does does not apply if we're declaring a 1855 // typedef (C++ [dcl.typedef]p4). 1856 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1857 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1858 PrevDecl = 0; 1859 1860 bool Redeclaration = false; 1861 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1862 if (TemplateParamLists.size()) { 1863 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1864 return DeclPtrTy(); 1865 } 1866 1867 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1868 } else if (R->isFunctionType()) { 1869 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1870 move(TemplateParamLists), 1871 IsFunctionDefinition, Redeclaration); 1872 } else { 1873 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1874 move(TemplateParamLists), 1875 Redeclaration); 1876 } 1877 1878 if (New == 0) 1879 return DeclPtrTy(); 1880 1881 // If this has an identifier and is not an invalid redeclaration or 1882 // function template specialization, add it to the scope stack. 1883 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1884 !(isa<FunctionDecl>(New) && 1885 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1886 PushOnScopeChains(New, S); 1887 1888 return DeclPtrTy::make(New); 1889} 1890 1891/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1892/// types into constant array types in certain situations which would otherwise 1893/// be errors (for GCC compatibility). 1894static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1895 ASTContext &Context, 1896 bool &SizeIsNegative) { 1897 // This method tries to turn a variable array into a constant 1898 // array even when the size isn't an ICE. This is necessary 1899 // for compatibility with code that depends on gcc's buggy 1900 // constant expression folding, like struct {char x[(int)(char*)2];} 1901 SizeIsNegative = false; 1902 1903 QualifierCollector Qs; 1904 const Type *Ty = Qs.strip(T); 1905 1906 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1907 QualType Pointee = PTy->getPointeeType(); 1908 QualType FixedType = 1909 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1910 if (FixedType.isNull()) return FixedType; 1911 FixedType = Context.getPointerType(FixedType); 1912 return Qs.apply(FixedType); 1913 } 1914 1915 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1916 if (!VLATy) 1917 return QualType(); 1918 // FIXME: We should probably handle this case 1919 if (VLATy->getElementType()->isVariablyModifiedType()) 1920 return QualType(); 1921 1922 Expr::EvalResult EvalResult; 1923 if (!VLATy->getSizeExpr() || 1924 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1925 !EvalResult.Val.isInt()) 1926 return QualType(); 1927 1928 llvm::APSInt &Res = EvalResult.Val.getInt(); 1929 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1930 // TODO: preserve the size expression in declarator info 1931 return Context.getConstantArrayType(VLATy->getElementType(), 1932 Res, ArrayType::Normal, 0); 1933 } 1934 1935 SizeIsNegative = true; 1936 return QualType(); 1937} 1938 1939/// \brief Register the given locally-scoped external C declaration so 1940/// that it can be found later for redeclarations 1941void 1942Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1943 Scope *S) { 1944 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1945 "Decl is not a locally-scoped decl!"); 1946 // Note that we have a locally-scoped external with this name. 1947 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1948 1949 if (!PrevDecl) 1950 return; 1951 1952 // If there was a previous declaration of this variable, it may be 1953 // in our identifier chain. Update the identifier chain with the new 1954 // declaration. 1955 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1956 // The previous declaration was found on the identifer resolver 1957 // chain, so remove it from its scope. 1958 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1959 S = S->getParent(); 1960 1961 if (S) 1962 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1963 } 1964} 1965 1966/// \brief Diagnose function specifiers on a declaration of an identifier that 1967/// does not identify a function. 1968void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1969 // FIXME: We should probably indicate the identifier in question to avoid 1970 // confusion for constructs like "inline int a(), b;" 1971 if (D.getDeclSpec().isInlineSpecified()) 1972 Diag(D.getDeclSpec().getInlineSpecLoc(), 1973 diag::err_inline_non_function); 1974 1975 if (D.getDeclSpec().isVirtualSpecified()) 1976 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1977 diag::err_virtual_non_function); 1978 1979 if (D.getDeclSpec().isExplicitSpecified()) 1980 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1981 diag::err_explicit_non_function); 1982} 1983 1984NamedDecl* 1985Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1986 QualType R, DeclaratorInfo *DInfo, 1987 NamedDecl* PrevDecl, bool &Redeclaration) { 1988 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1989 if (D.getCXXScopeSpec().isSet()) { 1990 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1991 << D.getCXXScopeSpec().getRange(); 1992 D.setInvalidType(); 1993 // Pretend we didn't see the scope specifier. 1994 DC = 0; 1995 } 1996 1997 if (getLangOptions().CPlusPlus) { 1998 // Check that there are no default arguments (C++ only). 1999 CheckExtraCXXDefaultArguments(D); 2000 } 2001 2002 DiagnoseFunctionSpecifiers(D); 2003 2004 if (D.getDeclSpec().isThreadSpecified()) 2005 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2006 2007 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 2008 if (!NewTD) return 0; 2009 2010 // Handle attributes prior to checking for duplicates in MergeVarDecl 2011 ProcessDeclAttributes(S, NewTD, D); 2012 // Merge the decl with the existing one if appropriate. If the decl is 2013 // in an outer scope, it isn't the same thing. 2014 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2015 Redeclaration = true; 2016 MergeTypeDefDecl(NewTD, PrevDecl); 2017 } 2018 2019 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2020 // then it shall have block scope. 2021 QualType T = NewTD->getUnderlyingType(); 2022 if (T->isVariablyModifiedType()) { 2023 CurFunctionNeedsScopeChecking = true; 2024 2025 if (S->getFnParent() == 0) { 2026 bool SizeIsNegative; 2027 QualType FixedTy = 2028 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2029 if (!FixedTy.isNull()) { 2030 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2031 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2032 } else { 2033 if (SizeIsNegative) 2034 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2035 else if (T->isVariableArrayType()) 2036 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2037 else 2038 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2039 NewTD->setInvalidDecl(); 2040 } 2041 } 2042 } 2043 2044 // If this is the C FILE type, notify the AST context. 2045 if (IdentifierInfo *II = NewTD->getIdentifier()) 2046 if (!NewTD->isInvalidDecl() && 2047 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2048 if (II->isStr("FILE")) 2049 Context.setFILEDecl(NewTD); 2050 else if (II->isStr("jmp_buf")) 2051 Context.setjmp_bufDecl(NewTD); 2052 else if (II->isStr("sigjmp_buf")) 2053 Context.setsigjmp_bufDecl(NewTD); 2054 } 2055 2056 return NewTD; 2057} 2058 2059/// \brief Determines whether the given declaration is an out-of-scope 2060/// previous declaration. 2061/// 2062/// This routine should be invoked when name lookup has found a 2063/// previous declaration (PrevDecl) that is not in the scope where a 2064/// new declaration by the same name is being introduced. If the new 2065/// declaration occurs in a local scope, previous declarations with 2066/// linkage may still be considered previous declarations (C99 2067/// 6.2.2p4-5, C++ [basic.link]p6). 2068/// 2069/// \param PrevDecl the previous declaration found by name 2070/// lookup 2071/// 2072/// \param DC the context in which the new declaration is being 2073/// declared. 2074/// 2075/// \returns true if PrevDecl is an out-of-scope previous declaration 2076/// for a new delcaration with the same name. 2077static bool 2078isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2079 ASTContext &Context) { 2080 if (!PrevDecl) 2081 return 0; 2082 2083 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2084 // case we need to check each of the overloaded functions. 2085 if (!PrevDecl->hasLinkage()) 2086 return false; 2087 2088 if (Context.getLangOptions().CPlusPlus) { 2089 // C++ [basic.link]p6: 2090 // If there is a visible declaration of an entity with linkage 2091 // having the same name and type, ignoring entities declared 2092 // outside the innermost enclosing namespace scope, the block 2093 // scope declaration declares that same entity and receives the 2094 // linkage of the previous declaration. 2095 DeclContext *OuterContext = DC->getLookupContext(); 2096 if (!OuterContext->isFunctionOrMethod()) 2097 // This rule only applies to block-scope declarations. 2098 return false; 2099 else { 2100 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2101 if (PrevOuterContext->isRecord()) 2102 // We found a member function: ignore it. 2103 return false; 2104 else { 2105 // Find the innermost enclosing namespace for the new and 2106 // previous declarations. 2107 while (!OuterContext->isFileContext()) 2108 OuterContext = OuterContext->getParent(); 2109 while (!PrevOuterContext->isFileContext()) 2110 PrevOuterContext = PrevOuterContext->getParent(); 2111 2112 // The previous declaration is in a different namespace, so it 2113 // isn't the same function. 2114 if (OuterContext->getPrimaryContext() != 2115 PrevOuterContext->getPrimaryContext()) 2116 return false; 2117 } 2118 } 2119 } 2120 2121 return true; 2122} 2123 2124NamedDecl* 2125Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2126 QualType R, DeclaratorInfo *DInfo, 2127 NamedDecl* PrevDecl, 2128 MultiTemplateParamsArg TemplateParamLists, 2129 bool &Redeclaration) { 2130 DeclarationName Name = GetNameForDeclarator(D); 2131 2132 // Check that there are no default arguments (C++ only). 2133 if (getLangOptions().CPlusPlus) 2134 CheckExtraCXXDefaultArguments(D); 2135 2136 VarDecl *NewVD; 2137 VarDecl::StorageClass SC; 2138 switch (D.getDeclSpec().getStorageClassSpec()) { 2139 default: assert(0 && "Unknown storage class!"); 2140 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2141 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2142 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2143 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2144 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2145 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2146 case DeclSpec::SCS_mutable: 2147 // mutable can only appear on non-static class members, so it's always 2148 // an error here 2149 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2150 D.setInvalidType(); 2151 SC = VarDecl::None; 2152 break; 2153 } 2154 2155 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2156 if (!II) { 2157 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2158 << Name.getAsString(); 2159 return 0; 2160 } 2161 2162 DiagnoseFunctionSpecifiers(D); 2163 2164 if (!DC->isRecord() && S->getFnParent() == 0) { 2165 // C99 6.9p2: The storage-class specifiers auto and register shall not 2166 // appear in the declaration specifiers in an external declaration. 2167 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2168 2169 // If this is a register variable with an asm label specified, then this 2170 // is a GNU extension. 2171 if (SC == VarDecl::Register && D.getAsmLabel()) 2172 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2173 else 2174 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2175 D.setInvalidType(); 2176 } 2177 } 2178 if (DC->isRecord() && !CurContext->isRecord()) { 2179 // This is an out-of-line definition of a static data member. 2180 if (SC == VarDecl::Static) { 2181 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2182 diag::err_static_out_of_line) 2183 << CodeModificationHint::CreateRemoval( 2184 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2185 } else if (SC == VarDecl::None) 2186 SC = VarDecl::Static; 2187 } 2188 if (SC == VarDecl::Static) { 2189 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2190 if (RD->isLocalClass()) 2191 Diag(D.getIdentifierLoc(), 2192 diag::err_static_data_member_not_allowed_in_local_class) 2193 << Name << RD->getDeclName(); 2194 } 2195 } 2196 2197 // Match up the template parameter lists with the scope specifier, then 2198 // determine whether we have a template or a template specialization. 2199 bool isExplicitSpecialization = false; 2200 if (TemplateParameterList *TemplateParams 2201 = MatchTemplateParametersToScopeSpecifier( 2202 D.getDeclSpec().getSourceRange().getBegin(), 2203 D.getCXXScopeSpec(), 2204 (TemplateParameterList**)TemplateParamLists.get(), 2205 TemplateParamLists.size(), 2206 isExplicitSpecialization)) { 2207 if (TemplateParams->size() > 0) { 2208 // There is no such thing as a variable template. 2209 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2210 << II 2211 << SourceRange(TemplateParams->getTemplateLoc(), 2212 TemplateParams->getRAngleLoc()); 2213 return 0; 2214 } else { 2215 // There is an extraneous 'template<>' for this variable. Complain 2216 // about it, but allow the declaration of the variable. 2217 Diag(TemplateParams->getTemplateLoc(), 2218 diag::err_template_variable_noparams) 2219 << II 2220 << SourceRange(TemplateParams->getTemplateLoc(), 2221 TemplateParams->getRAngleLoc()); 2222 2223 isExplicitSpecialization = true; 2224 } 2225 } 2226 2227 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2228 II, R, DInfo, SC); 2229 2230 if (D.isInvalidType()) 2231 NewVD->setInvalidDecl(); 2232 2233 if (D.getDeclSpec().isThreadSpecified()) { 2234 if (NewVD->hasLocalStorage()) 2235 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2236 else if (!Context.Target.isTLSSupported()) 2237 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2238 else 2239 NewVD->setThreadSpecified(true); 2240 } 2241 2242 // Set the lexical context. If the declarator has a C++ scope specifier, the 2243 // lexical context will be different from the semantic context. 2244 NewVD->setLexicalDeclContext(CurContext); 2245 2246 // Handle attributes prior to checking for duplicates in MergeVarDecl 2247 ProcessDeclAttributes(S, NewVD, D); 2248 2249 // Handle GNU asm-label extension (encoded as an attribute). 2250 if (Expr *E = (Expr*) D.getAsmLabel()) { 2251 // The parser guarantees this is a string. 2252 StringLiteral *SE = cast<StringLiteral>(E); 2253 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2254 SE->getByteLength()))); 2255 } 2256 2257 // If name lookup finds a previous declaration that is not in the 2258 // same scope as the new declaration, this may still be an 2259 // acceptable redeclaration. 2260 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2261 !(NewVD->hasLinkage() && 2262 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2263 PrevDecl = 0; 2264 2265 // Merge the decl with the existing one if appropriate. 2266 if (PrevDecl) { 2267 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2268 // The user tried to define a non-static data member 2269 // out-of-line (C++ [dcl.meaning]p1). 2270 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2271 << D.getCXXScopeSpec().getRange(); 2272 PrevDecl = 0; 2273 NewVD->setInvalidDecl(); 2274 } 2275 } else if (D.getCXXScopeSpec().isSet()) { 2276 // No previous declaration in the qualifying scope. 2277 Diag(D.getIdentifierLoc(), diag::err_no_member) 2278 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2279 << D.getCXXScopeSpec().getRange(); 2280 NewVD->setInvalidDecl(); 2281 } 2282 2283 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2284 2285 // This is an explicit specialization of a static data member. Check it. 2286 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2287 CheckMemberSpecialization(NewVD, PrevDecl)) 2288 NewVD->setInvalidDecl(); 2289 2290 // attributes declared post-definition are currently ignored 2291 if (PrevDecl) { 2292 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2293 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2294 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2295 Diag(Def->getLocation(), diag::note_previous_definition); 2296 } 2297 } 2298 2299 // If this is a locally-scoped extern C variable, update the map of 2300 // such variables. 2301 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2302 !NewVD->isInvalidDecl()) 2303 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2304 2305 return NewVD; 2306} 2307 2308/// \brief Perform semantic checking on a newly-created variable 2309/// declaration. 2310/// 2311/// This routine performs all of the type-checking required for a 2312/// variable declaration once it has been built. It is used both to 2313/// check variables after they have been parsed and their declarators 2314/// have been translated into a declaration, and to check variables 2315/// that have been instantiated from a template. 2316/// 2317/// Sets NewVD->isInvalidDecl() if an error was encountered. 2318void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2319 bool &Redeclaration) { 2320 // If the decl is already known invalid, don't check it. 2321 if (NewVD->isInvalidDecl()) 2322 return; 2323 2324 QualType T = NewVD->getType(); 2325 2326 if (T->isObjCInterfaceType()) { 2327 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2328 return NewVD->setInvalidDecl(); 2329 } 2330 2331 // The variable can not have an abstract class type. 2332 if (RequireNonAbstractType(NewVD->getLocation(), T, 2333 diag::err_abstract_type_in_decl, 2334 AbstractVariableType)) 2335 return NewVD->setInvalidDecl(); 2336 2337 // Emit an error if an address space was applied to decl with local storage. 2338 // This includes arrays of objects with address space qualifiers, but not 2339 // automatic variables that point to other address spaces. 2340 // ISO/IEC TR 18037 S5.1.2 2341 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2342 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2343 return NewVD->setInvalidDecl(); 2344 } 2345 2346 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2347 && !NewVD->hasAttr<BlocksAttr>()) 2348 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2349 2350 bool isVM = T->isVariablyModifiedType(); 2351 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2352 NewVD->hasAttr<BlocksAttr>()) 2353 CurFunctionNeedsScopeChecking = true; 2354 2355 if ((isVM && NewVD->hasLinkage()) || 2356 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2357 bool SizeIsNegative; 2358 QualType FixedTy = 2359 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2360 2361 if (FixedTy.isNull() && T->isVariableArrayType()) { 2362 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2363 // FIXME: This won't give the correct result for 2364 // int a[10][n]; 2365 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2366 2367 if (NewVD->isFileVarDecl()) 2368 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2369 << SizeRange; 2370 else if (NewVD->getStorageClass() == VarDecl::Static) 2371 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2372 << SizeRange; 2373 else 2374 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2375 << SizeRange; 2376 return NewVD->setInvalidDecl(); 2377 } 2378 2379 if (FixedTy.isNull()) { 2380 if (NewVD->isFileVarDecl()) 2381 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2382 else 2383 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2384 return NewVD->setInvalidDecl(); 2385 } 2386 2387 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2388 NewVD->setType(FixedTy); 2389 } 2390 2391 if (!PrevDecl && NewVD->isExternC()) { 2392 // Since we did not find anything by this name and we're declaring 2393 // an extern "C" variable, look for a non-visible extern "C" 2394 // declaration with the same name. 2395 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2396 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2397 if (Pos != LocallyScopedExternalDecls.end()) 2398 PrevDecl = Pos->second; 2399 } 2400 2401 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2402 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2403 << T; 2404 return NewVD->setInvalidDecl(); 2405 } 2406 2407 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2408 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2409 return NewVD->setInvalidDecl(); 2410 } 2411 2412 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2413 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2414 return NewVD->setInvalidDecl(); 2415 } 2416 2417 if (PrevDecl) { 2418 Redeclaration = true; 2419 MergeVarDecl(NewVD, PrevDecl); 2420 } 2421} 2422 2423static bool isUsingDecl(Decl *D) { 2424 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2425} 2426 2427/// \brief Data used with FindOverriddenMethod 2428struct FindOverriddenMethodData { 2429 Sema *S; 2430 CXXMethodDecl *Method; 2431}; 2432 2433/// \brief Member lookup function that determines whether a given C++ 2434/// method overrides a method in a base class, to be used with 2435/// CXXRecordDecl::lookupInBases(). 2436static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2437 CXXBasePath &Path, 2438 void *UserData) { 2439 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2440 2441 FindOverriddenMethodData *Data 2442 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2443 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2444 Path.Decls.first != Path.Decls.second; 2445 ++Path.Decls.first) { 2446 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2447 OverloadedFunctionDecl::function_iterator MatchedDecl; 2448 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2449 return true; 2450 } 2451 } 2452 2453 return false; 2454} 2455 2456NamedDecl* 2457Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2458 QualType R, DeclaratorInfo *DInfo, 2459 NamedDecl* PrevDecl, 2460 MultiTemplateParamsArg TemplateParamLists, 2461 bool IsFunctionDefinition, bool &Redeclaration) { 2462 assert(R.getTypePtr()->isFunctionType()); 2463 2464 DeclarationName Name = GetNameForDeclarator(D); 2465 FunctionDecl::StorageClass SC = FunctionDecl::None; 2466 switch (D.getDeclSpec().getStorageClassSpec()) { 2467 default: assert(0 && "Unknown storage class!"); 2468 case DeclSpec::SCS_auto: 2469 case DeclSpec::SCS_register: 2470 case DeclSpec::SCS_mutable: 2471 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2472 diag::err_typecheck_sclass_func); 2473 D.setInvalidType(); 2474 break; 2475 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2476 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2477 case DeclSpec::SCS_static: { 2478 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2479 // C99 6.7.1p5: 2480 // The declaration of an identifier for a function that has 2481 // block scope shall have no explicit storage-class specifier 2482 // other than extern 2483 // See also (C++ [dcl.stc]p4). 2484 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2485 diag::err_static_block_func); 2486 SC = FunctionDecl::None; 2487 } else 2488 SC = FunctionDecl::Static; 2489 break; 2490 } 2491 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2492 } 2493 2494 if (D.getDeclSpec().isThreadSpecified()) 2495 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2496 2497 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2498 bool isInline = D.getDeclSpec().isInlineSpecified(); 2499 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2500 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2501 2502 // Check that the return type is not an abstract class type. 2503 // For record types, this is done by the AbstractClassUsageDiagnoser once 2504 // the class has been completely parsed. 2505 if (!DC->isRecord() && 2506 RequireNonAbstractType(D.getIdentifierLoc(), 2507 R->getAs<FunctionType>()->getResultType(), 2508 diag::err_abstract_type_in_decl, 2509 AbstractReturnType)) 2510 D.setInvalidType(); 2511 2512 // Do not allow returning a objc interface by-value. 2513 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2514 Diag(D.getIdentifierLoc(), 2515 diag::err_object_cannot_be_passed_returned_by_value) << 0 2516 << R->getAs<FunctionType>()->getResultType(); 2517 D.setInvalidType(); 2518 } 2519 2520 bool isVirtualOkay = false; 2521 FunctionDecl *NewFD; 2522 2523 if (isFriend) { 2524 // DC is the namespace in which the function is being declared. 2525 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2526 "friend function being created in a non-namespace context"); 2527 2528 // C++ [class.friend]p5 2529 // A function can be defined in a friend declaration of a 2530 // class . . . . Such a function is implicitly inline. 2531 isInline |= IsFunctionDefinition; 2532 } 2533 2534 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2535 // This is a C++ constructor declaration. 2536 assert(DC->isRecord() && 2537 "Constructors can only be declared in a member context"); 2538 2539 R = CheckConstructorDeclarator(D, R, SC); 2540 2541 // Create the new declaration 2542 NewFD = CXXConstructorDecl::Create(Context, 2543 cast<CXXRecordDecl>(DC), 2544 D.getIdentifierLoc(), Name, R, DInfo, 2545 isExplicit, isInline, 2546 /*isImplicitlyDeclared=*/false); 2547 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2548 // This is a C++ destructor declaration. 2549 if (DC->isRecord()) { 2550 R = CheckDestructorDeclarator(D, SC); 2551 2552 NewFD = CXXDestructorDecl::Create(Context, 2553 cast<CXXRecordDecl>(DC), 2554 D.getIdentifierLoc(), Name, R, 2555 isInline, 2556 /*isImplicitlyDeclared=*/false); 2557 2558 isVirtualOkay = true; 2559 } else { 2560 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2561 2562 // Create a FunctionDecl to satisfy the function definition parsing 2563 // code path. 2564 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2565 Name, R, DInfo, SC, isInline, 2566 /*hasPrototype=*/true); 2567 D.setInvalidType(); 2568 } 2569 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2570 if (!DC->isRecord()) { 2571 Diag(D.getIdentifierLoc(), 2572 diag::err_conv_function_not_member); 2573 return 0; 2574 } 2575 2576 CheckConversionDeclarator(D, R, SC); 2577 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2578 D.getIdentifierLoc(), Name, R, DInfo, 2579 isInline, isExplicit); 2580 2581 isVirtualOkay = true; 2582 } else if (DC->isRecord()) { 2583 // If the of the function is the same as the name of the record, then this 2584 // must be an invalid constructor that has a return type. 2585 // (The parser checks for a return type and makes the declarator a 2586 // constructor if it has no return type). 2587 // must have an invalid constructor that has a return type 2588 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2589 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2590 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2591 << SourceRange(D.getIdentifierLoc()); 2592 return 0; 2593 } 2594 2595 // This is a C++ method declaration. 2596 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2597 D.getIdentifierLoc(), Name, R, DInfo, 2598 (SC == FunctionDecl::Static), isInline); 2599 2600 isVirtualOkay = (SC != FunctionDecl::Static); 2601 } else { 2602 // Determine whether the function was written with a 2603 // prototype. This true when: 2604 // - we're in C++ (where every function has a prototype), 2605 // - there is a prototype in the declarator, or 2606 // - the type R of the function is some kind of typedef or other reference 2607 // to a type name (which eventually refers to a function type). 2608 bool HasPrototype = 2609 getLangOptions().CPlusPlus || 2610 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2611 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2612 2613 NewFD = FunctionDecl::Create(Context, DC, 2614 D.getIdentifierLoc(), 2615 Name, R, DInfo, SC, isInline, HasPrototype); 2616 } 2617 2618 if (D.isInvalidType()) 2619 NewFD->setInvalidDecl(); 2620 2621 // Set the lexical context. If the declarator has a C++ 2622 // scope specifier, or is the object of a friend declaration, the 2623 // lexical context will be different from the semantic context. 2624 NewFD->setLexicalDeclContext(CurContext); 2625 2626 // Match up the template parameter lists with the scope specifier, then 2627 // determine whether we have a template or a template specialization. 2628 FunctionTemplateDecl *FunctionTemplate = 0; 2629 bool isExplicitSpecialization = false; 2630 bool isFunctionTemplateSpecialization = false; 2631 if (TemplateParameterList *TemplateParams 2632 = MatchTemplateParametersToScopeSpecifier( 2633 D.getDeclSpec().getSourceRange().getBegin(), 2634 D.getCXXScopeSpec(), 2635 (TemplateParameterList**)TemplateParamLists.get(), 2636 TemplateParamLists.size(), 2637 isExplicitSpecialization)) { 2638 if (TemplateParams->size() > 0) { 2639 // This is a function template 2640 2641 // Check that we can declare a template here. 2642 if (CheckTemplateDeclScope(S, TemplateParams)) 2643 return 0; 2644 2645 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2646 NewFD->getLocation(), 2647 Name, TemplateParams, 2648 NewFD); 2649 FunctionTemplate->setLexicalDeclContext(CurContext); 2650 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2651 } else { 2652 // This is a function template specialization. 2653 isFunctionTemplateSpecialization = true; 2654 } 2655 2656 // FIXME: Free this memory properly. 2657 TemplateParamLists.release(); 2658 } 2659 2660 // C++ [dcl.fct.spec]p5: 2661 // The virtual specifier shall only be used in declarations of 2662 // nonstatic class member functions that appear within a 2663 // member-specification of a class declaration; see 10.3. 2664 // 2665 if (isVirtual && !NewFD->isInvalidDecl()) { 2666 if (!isVirtualOkay) { 2667 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2668 diag::err_virtual_non_function); 2669 } else if (!CurContext->isRecord()) { 2670 // 'virtual' was specified outside of the class. 2671 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2672 << CodeModificationHint::CreateRemoval( 2673 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2674 } else { 2675 // Okay: Add virtual to the method. 2676 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2677 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2678 CurClass->setAggregate(false); 2679 CurClass->setPOD(false); 2680 CurClass->setEmpty(false); 2681 CurClass->setPolymorphic(true); 2682 CurClass->setHasTrivialConstructor(false); 2683 CurClass->setHasTrivialCopyConstructor(false); 2684 CurClass->setHasTrivialCopyAssignment(false); 2685 } 2686 } 2687 2688 if (isFriend) { 2689 if (FunctionTemplate) { 2690 FunctionTemplate->setObjectOfFriendDecl( 2691 /* PreviouslyDeclared= */ PrevDecl != NULL); 2692 FunctionTemplate->setAccess(AS_public); 2693 } 2694 else 2695 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2696 2697 NewFD->setAccess(AS_public); 2698 } 2699 2700 2701 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2702 // Look for virtual methods in base classes that this method might override. 2703 CXXBasePaths Paths; 2704 FindOverriddenMethodData Data; 2705 Data.Method = NewMD; 2706 Data.S = this; 2707 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2708 Paths)) { 2709 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2710 E = Paths.found_decls_end(); I != E; ++I) { 2711 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2712 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2713 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2714 NewMD->addOverriddenMethod(OldMD); 2715 } 2716 } 2717 } 2718 } 2719 2720 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2721 !CurContext->isRecord()) { 2722 // C++ [class.static]p1: 2723 // A data or function member of a class may be declared static 2724 // in a class definition, in which case it is a static member of 2725 // the class. 2726 2727 // Complain about the 'static' specifier if it's on an out-of-line 2728 // member function definition. 2729 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2730 diag::err_static_out_of_line) 2731 << CodeModificationHint::CreateRemoval( 2732 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2733 } 2734 2735 // Handle GNU asm-label extension (encoded as an attribute). 2736 if (Expr *E = (Expr*) D.getAsmLabel()) { 2737 // The parser guarantees this is a string. 2738 StringLiteral *SE = cast<StringLiteral>(E); 2739 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2740 SE->getByteLength()))); 2741 } 2742 2743 // Copy the parameter declarations from the declarator D to the function 2744 // declaration NewFD, if they are available. First scavenge them into Params. 2745 llvm::SmallVector<ParmVarDecl*, 16> Params; 2746 if (D.getNumTypeObjects() > 0) { 2747 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2748 2749 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2750 // function that takes no arguments, not a function that takes a 2751 // single void argument. 2752 // We let through "const void" here because Sema::GetTypeForDeclarator 2753 // already checks for that case. 2754 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2755 FTI.ArgInfo[0].Param && 2756 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2757 // Empty arg list, don't push any params. 2758 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2759 2760 // In C++, the empty parameter-type-list must be spelled "void"; a 2761 // typedef of void is not permitted. 2762 if (getLangOptions().CPlusPlus && 2763 Param->getType().getUnqualifiedType() != Context.VoidTy) 2764 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2765 // FIXME: Leaks decl? 2766 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2767 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2768 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2769 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2770 Param->setDeclContext(NewFD); 2771 Params.push_back(Param); 2772 } 2773 } 2774 2775 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2776 // When we're declaring a function with a typedef, typeof, etc as in the 2777 // following example, we'll need to synthesize (unnamed) 2778 // parameters for use in the declaration. 2779 // 2780 // @code 2781 // typedef void fn(int); 2782 // fn f; 2783 // @endcode 2784 2785 // Synthesize a parameter for each argument type. 2786 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2787 AE = FT->arg_type_end(); AI != AE; ++AI) { 2788 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2789 SourceLocation(), 0, 2790 *AI, /*DInfo=*/0, 2791 VarDecl::None, 0); 2792 Param->setImplicit(); 2793 Params.push_back(Param); 2794 } 2795 } else { 2796 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2797 "Should not need args for typedef of non-prototype fn"); 2798 } 2799 // Finally, we know we have the right number of parameters, install them. 2800 NewFD->setParams(Context, Params.data(), Params.size()); 2801 2802 // If name lookup finds a previous declaration that is not in the 2803 // same scope as the new declaration, this may still be an 2804 // acceptable redeclaration. 2805 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2806 !(NewFD->hasLinkage() && 2807 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2808 PrevDecl = 0; 2809 2810 // If the declarator is a template-id, translate the parser's template 2811 // argument list into our AST format. 2812 bool HasExplicitTemplateArgs = false; 2813 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 2814 SourceLocation LAngleLoc, RAngleLoc; 2815 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2816 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2817 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2818 TemplateId->getTemplateArgs(), 2819 TemplateId->getTemplateArgIsType(), 2820 TemplateId->NumArgs); 2821 translateTemplateArguments(TemplateArgsPtr, 2822 TemplateId->getTemplateArgLocations(), 2823 TemplateArgs); 2824 TemplateArgsPtr.release(); 2825 2826 HasExplicitTemplateArgs = true; 2827 LAngleLoc = TemplateId->LAngleLoc; 2828 RAngleLoc = TemplateId->RAngleLoc; 2829 2830 if (FunctionTemplate) { 2831 // FIXME: Diagnose function template with explicit template 2832 // arguments. 2833 HasExplicitTemplateArgs = false; 2834 } else if (!isFunctionTemplateSpecialization && 2835 !D.getDeclSpec().isFriendSpecified()) { 2836 // We have encountered something that the user meant to be a 2837 // specialization (because it has explicitly-specified template 2838 // arguments) but that was not introduced with a "template<>" (or had 2839 // too few of them). 2840 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2841 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2842 << CodeModificationHint::CreateInsertion( 2843 D.getDeclSpec().getSourceRange().getBegin(), 2844 "template<> "); 2845 isFunctionTemplateSpecialization = true; 2846 } 2847 } 2848 2849 if (isFunctionTemplateSpecialization) { 2850 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2851 LAngleLoc, TemplateArgs.data(), 2852 TemplateArgs.size(), RAngleLoc, 2853 PrevDecl)) 2854 NewFD->setInvalidDecl(); 2855 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2856 CheckMemberSpecialization(NewFD, PrevDecl)) 2857 NewFD->setInvalidDecl(); 2858 2859 // Perform semantic checking on the function declaration. 2860 bool OverloadableAttrRequired = false; // FIXME: HACK! 2861 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2862 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2863 2864 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2865 // An out-of-line member function declaration must also be a 2866 // definition (C++ [dcl.meaning]p1). 2867 // Note that this is not the case for explicit specializations of 2868 // function templates or member functions of class templates, per 2869 // C++ [temp.expl.spec]p2. 2870 if (!IsFunctionDefinition && !isFriend && 2871 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2872 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2873 << D.getCXXScopeSpec().getRange(); 2874 NewFD->setInvalidDecl(); 2875 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2876 // The user tried to provide an out-of-line definition for a 2877 // function that is a member of a class or namespace, but there 2878 // was no such member function declared (C++ [class.mfct]p2, 2879 // C++ [namespace.memdef]p2). For example: 2880 // 2881 // class X { 2882 // void f() const; 2883 // }; 2884 // 2885 // void X::f() { } // ill-formed 2886 // 2887 // Complain about this problem, and attempt to suggest close 2888 // matches (e.g., those that differ only in cv-qualifiers and 2889 // whether the parameter types are references). 2890 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2891 << Name << DC << D.getCXXScopeSpec().getRange(); 2892 NewFD->setInvalidDecl(); 2893 2894 LookupResult Prev; 2895 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2896 assert(!Prev.isAmbiguous() && 2897 "Cannot have an ambiguity in previous-declaration lookup"); 2898 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2899 Func != FuncEnd; ++Func) { 2900 if (isa<FunctionDecl>(*Func) && 2901 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2902 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2903 } 2904 2905 PrevDecl = 0; 2906 } 2907 } 2908 2909 // Handle attributes. We need to have merged decls when handling attributes 2910 // (for example to check for conflicts, etc). 2911 // FIXME: This needs to happen before we merge declarations. Then, 2912 // let attribute merging cope with attribute conflicts. 2913 ProcessDeclAttributes(S, NewFD, D); 2914 2915 // attributes declared post-definition are currently ignored 2916 if (Redeclaration && PrevDecl) { 2917 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2918 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2919 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2920 Diag(Def->getLocation(), diag::note_previous_definition); 2921 } 2922 } 2923 2924 AddKnownFunctionAttributes(NewFD); 2925 2926 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2927 // If a function name is overloadable in C, then every function 2928 // with that name must be marked "overloadable". 2929 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2930 << Redeclaration << NewFD; 2931 if (PrevDecl) 2932 Diag(PrevDecl->getLocation(), 2933 diag::note_attribute_overloadable_prev_overload); 2934 NewFD->addAttr(::new (Context) OverloadableAttr()); 2935 } 2936 2937 // If this is a locally-scoped extern C function, update the 2938 // map of such names. 2939 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2940 && !NewFD->isInvalidDecl()) 2941 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2942 2943 // Set this FunctionDecl's range up to the right paren. 2944 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2945 2946 if (FunctionTemplate && NewFD->isInvalidDecl()) 2947 FunctionTemplate->setInvalidDecl(); 2948 2949 if (FunctionTemplate) 2950 return FunctionTemplate; 2951 2952 return NewFD; 2953} 2954 2955/// \brief Perform semantic checking of a new function declaration. 2956/// 2957/// Performs semantic analysis of the new function declaration 2958/// NewFD. This routine performs all semantic checking that does not 2959/// require the actual declarator involved in the declaration, and is 2960/// used both for the declaration of functions as they are parsed 2961/// (called via ActOnDeclarator) and for the declaration of functions 2962/// that have been instantiated via C++ template instantiation (called 2963/// via InstantiateDecl). 2964/// 2965/// \param IsExplicitSpecialiation whether this new function declaration is 2966/// an explicit specialization of the previous declaration. 2967/// 2968/// This sets NewFD->isInvalidDecl() to true if there was an error. 2969void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2970 bool IsExplicitSpecialization, 2971 bool &Redeclaration, 2972 bool &OverloadableAttrRequired) { 2973 // If NewFD is already known erroneous, don't do any of this checking. 2974 if (NewFD->isInvalidDecl()) 2975 return; 2976 2977 if (NewFD->getResultType()->isVariablyModifiedType()) { 2978 // Functions returning a variably modified type violate C99 6.7.5.2p2 2979 // because all functions have linkage. 2980 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2981 return NewFD->setInvalidDecl(); 2982 } 2983 2984 if (NewFD->isMain()) 2985 CheckMain(NewFD); 2986 2987 // Check for a previous declaration of this name. 2988 if (!PrevDecl && NewFD->isExternC()) { 2989 // Since we did not find anything by this name and we're declaring 2990 // an extern "C" function, look for a non-visible extern "C" 2991 // declaration with the same name. 2992 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2993 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2994 if (Pos != LocallyScopedExternalDecls.end()) 2995 PrevDecl = Pos->second; 2996 } 2997 2998 // Merge or overload the declaration with an existing declaration of 2999 // the same name, if appropriate. 3000 if (PrevDecl) { 3001 // Determine whether NewFD is an overload of PrevDecl or 3002 // a declaration that requires merging. If it's an overload, 3003 // there's no more work to do here; we'll just add the new 3004 // function to the scope. 3005 OverloadedFunctionDecl::function_iterator MatchedDecl; 3006 3007 if (!getLangOptions().CPlusPlus && 3008 AllowOverloadingOfFunction(PrevDecl, Context)) { 3009 OverloadableAttrRequired = true; 3010 3011 // Functions marked "overloadable" must have a prototype (that 3012 // we can't get through declaration merging). 3013 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3014 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3015 << NewFD; 3016 Redeclaration = true; 3017 3018 // Turn this into a variadic function with no parameters. 3019 QualType R = Context.getFunctionType( 3020 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3021 0, 0, true, 0); 3022 NewFD->setType(R); 3023 return NewFD->setInvalidDecl(); 3024 } 3025 } 3026 3027 if (PrevDecl && 3028 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3029 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3030 Redeclaration = true; 3031 Decl *OldDecl = PrevDecl; 3032 3033 // If PrevDecl was an overloaded function, extract the 3034 // FunctionDecl that matched. 3035 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3036 OldDecl = *MatchedDecl; 3037 3038 // NewFD and OldDecl represent declarations that need to be 3039 // merged. 3040 if (MergeFunctionDecl(NewFD, OldDecl)) 3041 return NewFD->setInvalidDecl(); 3042 3043 if (FunctionTemplateDecl *OldTemplateDecl 3044 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3045 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3046 FunctionTemplateDecl *NewTemplateDecl 3047 = NewFD->getDescribedFunctionTemplate(); 3048 assert(NewTemplateDecl && "Template/non-template mismatch"); 3049 if (CXXMethodDecl *Method 3050 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3051 Method->setAccess(OldTemplateDecl->getAccess()); 3052 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3053 } 3054 3055 // If this is an explicit specialization of a member that is a function 3056 // template, mark it as a member specialization. 3057 if (IsExplicitSpecialization && 3058 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3059 NewTemplateDecl->setMemberSpecialization(); 3060 assert(OldTemplateDecl->isMemberSpecialization()); 3061 } 3062 } else { 3063 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3064 NewFD->setAccess(OldDecl->getAccess()); 3065 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3066 } 3067 } 3068 } 3069 3070 // Semantic checking for this function declaration (in isolation). 3071 if (getLangOptions().CPlusPlus) { 3072 // C++-specific checks. 3073 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3074 CheckConstructor(Constructor); 3075 } else if (isa<CXXDestructorDecl>(NewFD)) { 3076 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3077 QualType ClassType = Context.getTypeDeclType(Record); 3078 if (!ClassType->isDependentType()) { 3079 DeclarationName Name 3080 = Context.DeclarationNames.getCXXDestructorName( 3081 Context.getCanonicalType(ClassType)); 3082 if (NewFD->getDeclName() != Name) { 3083 Diag(NewFD->getLocation(), diag::err_destructor_name); 3084 return NewFD->setInvalidDecl(); 3085 } 3086 } 3087 Record->setUserDeclaredDestructor(true); 3088 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3089 // user-defined destructor. 3090 Record->setPOD(false); 3091 3092 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3093 // declared destructor. 3094 // FIXME: C++0x: don't do this for "= default" destructors 3095 Record->setHasTrivialDestructor(false); 3096 } else if (CXXConversionDecl *Conversion 3097 = dyn_cast<CXXConversionDecl>(NewFD)) 3098 ActOnConversionDeclarator(Conversion); 3099 3100 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3101 if (NewFD->isOverloadedOperator() && 3102 CheckOverloadedOperatorDeclaration(NewFD)) 3103 return NewFD->setInvalidDecl(); 3104 3105 // In C++, check default arguments now that we have merged decls. Unless 3106 // the lexical context is the class, because in this case this is done 3107 // during delayed parsing anyway. 3108 if (!CurContext->isRecord()) 3109 CheckCXXDefaultArguments(NewFD); 3110 } 3111} 3112 3113void Sema::CheckMain(FunctionDecl* FD) { 3114 // C++ [basic.start.main]p3: A program that declares main to be inline 3115 // or static is ill-formed. 3116 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3117 // shall not appear in a declaration of main. 3118 // static main is not an error under C99, but we should warn about it. 3119 bool isInline = FD->isInlineSpecified(); 3120 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3121 if (isInline || isStatic) { 3122 unsigned diagID = diag::warn_unusual_main_decl; 3123 if (isInline || getLangOptions().CPlusPlus) 3124 diagID = diag::err_unusual_main_decl; 3125 3126 int which = isStatic + (isInline << 1) - 1; 3127 Diag(FD->getLocation(), diagID) << which; 3128 } 3129 3130 QualType T = FD->getType(); 3131 assert(T->isFunctionType() && "function decl is not of function type"); 3132 const FunctionType* FT = T->getAs<FunctionType>(); 3133 3134 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3135 // TODO: add a replacement fixit to turn the return type into 'int'. 3136 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3137 FD->setInvalidDecl(true); 3138 } 3139 3140 // Treat protoless main() as nullary. 3141 if (isa<FunctionNoProtoType>(FT)) return; 3142 3143 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3144 unsigned nparams = FTP->getNumArgs(); 3145 assert(FD->getNumParams() == nparams); 3146 3147 if (nparams > 3) { 3148 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3149 FD->setInvalidDecl(true); 3150 nparams = 3; 3151 } 3152 3153 // FIXME: a lot of the following diagnostics would be improved 3154 // if we had some location information about types. 3155 3156 QualType CharPP = 3157 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3158 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3159 3160 for (unsigned i = 0; i < nparams; ++i) { 3161 QualType AT = FTP->getArgType(i); 3162 3163 bool mismatch = true; 3164 3165 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3166 mismatch = false; 3167 else if (Expected[i] == CharPP) { 3168 // As an extension, the following forms are okay: 3169 // char const ** 3170 // char const * const * 3171 // char * const * 3172 3173 QualifierCollector qs; 3174 const PointerType* PT; 3175 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3176 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3177 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3178 qs.removeConst(); 3179 mismatch = !qs.empty(); 3180 } 3181 } 3182 3183 if (mismatch) { 3184 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3185 // TODO: suggest replacing given type with expected type 3186 FD->setInvalidDecl(true); 3187 } 3188 } 3189 3190 if (nparams == 1 && !FD->isInvalidDecl()) { 3191 Diag(FD->getLocation(), diag::warn_main_one_arg); 3192 } 3193} 3194 3195bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3196 // FIXME: Need strict checking. In C89, we need to check for 3197 // any assignment, increment, decrement, function-calls, or 3198 // commas outside of a sizeof. In C99, it's the same list, 3199 // except that the aforementioned are allowed in unevaluated 3200 // expressions. Everything else falls under the 3201 // "may accept other forms of constant expressions" exception. 3202 // (We never end up here for C++, so the constant expression 3203 // rules there don't matter.) 3204 if (Init->isConstantInitializer(Context)) 3205 return false; 3206 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3207 << Init->getSourceRange(); 3208 return true; 3209} 3210 3211void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3212 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3213} 3214 3215/// AddInitializerToDecl - Adds the initializer Init to the 3216/// declaration dcl. If DirectInit is true, this is C++ direct 3217/// initialization rather than copy initialization. 3218void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3219 Decl *RealDecl = dcl.getAs<Decl>(); 3220 // If there is no declaration, there was an error parsing it. Just ignore 3221 // the initializer. 3222 if (RealDecl == 0) 3223 return; 3224 3225 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3226 // With declarators parsed the way they are, the parser cannot 3227 // distinguish between a normal initializer and a pure-specifier. 3228 // Thus this grotesque test. 3229 IntegerLiteral *IL; 3230 Expr *Init = static_cast<Expr *>(init.get()); 3231 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3232 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3233 if (Method->isVirtualAsWritten()) { 3234 Method->setPure(); 3235 3236 // A class is abstract if at least one function is pure virtual. 3237 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3238 } else if (!Method->isInvalidDecl()) { 3239 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3240 << Method->getDeclName() << Init->getSourceRange(); 3241 Method->setInvalidDecl(); 3242 } 3243 } else { 3244 Diag(Method->getLocation(), diag::err_member_function_initialization) 3245 << Method->getDeclName() << Init->getSourceRange(); 3246 Method->setInvalidDecl(); 3247 } 3248 return; 3249 } 3250 3251 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3252 if (!VDecl) { 3253 if (getLangOptions().CPlusPlus && 3254 RealDecl->getLexicalDeclContext()->isRecord() && 3255 isa<NamedDecl>(RealDecl)) 3256 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3257 << cast<NamedDecl>(RealDecl)->getDeclName(); 3258 else 3259 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3260 RealDecl->setInvalidDecl(); 3261 return; 3262 } 3263 3264 if (!VDecl->getType()->isArrayType() && 3265 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3266 diag::err_typecheck_decl_incomplete_type)) { 3267 RealDecl->setInvalidDecl(); 3268 return; 3269 } 3270 3271 const VarDecl *Def = 0; 3272 if (VDecl->getDefinition(Def)) { 3273 Diag(VDecl->getLocation(), diag::err_redefinition) 3274 << VDecl->getDeclName(); 3275 Diag(Def->getLocation(), diag::note_previous_definition); 3276 VDecl->setInvalidDecl(); 3277 return; 3278 } 3279 3280 // Take ownership of the expression, now that we're sure we have somewhere 3281 // to put it. 3282 Expr *Init = init.takeAs<Expr>(); 3283 assert(Init && "missing initializer"); 3284 3285 // Get the decls type and save a reference for later, since 3286 // CheckInitializerTypes may change it. 3287 QualType DclT = VDecl->getType(), SavT = DclT; 3288 if (VDecl->isBlockVarDecl()) { 3289 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3290 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3291 VDecl->setInvalidDecl(); 3292 } else if (!VDecl->isInvalidDecl()) { 3293 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3294 VDecl->getDeclName(), DirectInit)) 3295 VDecl->setInvalidDecl(); 3296 3297 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3298 // Don't check invalid declarations to avoid emitting useless diagnostics. 3299 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3300 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3301 CheckForConstantInitializer(Init, DclT); 3302 } 3303 } 3304 } else if (VDecl->isStaticDataMember() && 3305 VDecl->getLexicalDeclContext()->isRecord()) { 3306 // This is an in-class initialization for a static data member, e.g., 3307 // 3308 // struct S { 3309 // static const int value = 17; 3310 // }; 3311 3312 // Attach the initializer 3313 VDecl->setInit(Context, Init); 3314 3315 // C++ [class.mem]p4: 3316 // A member-declarator can contain a constant-initializer only 3317 // if it declares a static member (9.4) of const integral or 3318 // const enumeration type, see 9.4.2. 3319 QualType T = VDecl->getType(); 3320 if (!T->isDependentType() && 3321 (!Context.getCanonicalType(T).isConstQualified() || 3322 !T->isIntegralType())) { 3323 Diag(VDecl->getLocation(), diag::err_member_initialization) 3324 << VDecl->getDeclName() << Init->getSourceRange(); 3325 VDecl->setInvalidDecl(); 3326 } else { 3327 // C++ [class.static.data]p4: 3328 // If a static data member is of const integral or const 3329 // enumeration type, its declaration in the class definition 3330 // can specify a constant-initializer which shall be an 3331 // integral constant expression (5.19). 3332 if (!Init->isTypeDependent() && 3333 !Init->getType()->isIntegralType()) { 3334 // We have a non-dependent, non-integral or enumeration type. 3335 Diag(Init->getSourceRange().getBegin(), 3336 diag::err_in_class_initializer_non_integral_type) 3337 << Init->getType() << Init->getSourceRange(); 3338 VDecl->setInvalidDecl(); 3339 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3340 // Check whether the expression is a constant expression. 3341 llvm::APSInt Value; 3342 SourceLocation Loc; 3343 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3344 Diag(Loc, diag::err_in_class_initializer_non_constant) 3345 << Init->getSourceRange(); 3346 VDecl->setInvalidDecl(); 3347 } else if (!VDecl->getType()->isDependentType()) 3348 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3349 } 3350 } 3351 } else if (VDecl->isFileVarDecl()) { 3352 if (VDecl->getStorageClass() == VarDecl::Extern) 3353 Diag(VDecl->getLocation(), diag::warn_extern_init); 3354 if (!VDecl->isInvalidDecl()) 3355 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3356 VDecl->getDeclName(), DirectInit)) 3357 VDecl->setInvalidDecl(); 3358 3359 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3360 // Don't check invalid declarations to avoid emitting useless diagnostics. 3361 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3362 // C99 6.7.8p4. All file scoped initializers need to be constant. 3363 CheckForConstantInitializer(Init, DclT); 3364 } 3365 } 3366 // If the type changed, it means we had an incomplete type that was 3367 // completed by the initializer. For example: 3368 // int ary[] = { 1, 3, 5 }; 3369 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3370 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3371 VDecl->setType(DclT); 3372 Init->setType(DclT); 3373 } 3374 3375 Init = MaybeCreateCXXExprWithTemporaries(Init, 3376 /*ShouldDestroyTemporaries=*/true); 3377 // Attach the initializer to the decl. 3378 VDecl->setInit(Context, Init); 3379 3380 // If the previous declaration of VDecl was a tentative definition, 3381 // remove it from the set of tentative definitions. 3382 if (VDecl->getPreviousDeclaration() && 3383 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3384 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3385 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3386 } 3387 3388 return; 3389} 3390 3391void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3392 bool TypeContainsUndeducedAuto) { 3393 Decl *RealDecl = dcl.getAs<Decl>(); 3394 3395 // If there is no declaration, there was an error parsing it. Just ignore it. 3396 if (RealDecl == 0) 3397 return; 3398 3399 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3400 QualType Type = Var->getType(); 3401 3402 // Record tentative definitions. 3403 if (Var->isTentativeDefinition(Context)) { 3404 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3405 InsertPair = 3406 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3407 3408 // Keep the latest definition in the map. If we see 'int i; int i;' we 3409 // want the second one in the map. 3410 InsertPair.first->second = Var; 3411 3412 // However, for the list, we don't care about the order, just make sure 3413 // that there are no dupes for a given declaration name. 3414 if (InsertPair.second) 3415 TentativeDefinitionList.push_back(Var->getDeclName()); 3416 } 3417 3418 // C++ [dcl.init.ref]p3: 3419 // The initializer can be omitted for a reference only in a 3420 // parameter declaration (8.3.5), in the declaration of a 3421 // function return type, in the declaration of a class member 3422 // within its class declaration (9.2), and where the extern 3423 // specifier is explicitly used. 3424 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3425 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3426 << Var->getDeclName() 3427 << SourceRange(Var->getLocation(), Var->getLocation()); 3428 Var->setInvalidDecl(); 3429 return; 3430 } 3431 3432 // C++0x [dcl.spec.auto]p3 3433 if (TypeContainsUndeducedAuto) { 3434 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3435 << Var->getDeclName() << Type; 3436 Var->setInvalidDecl(); 3437 return; 3438 } 3439 3440 // An array without size is an incomplete type, and there are no special 3441 // rules in C++ to make such a definition acceptable. 3442 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3443 !Var->hasExternalStorage()) { 3444 Diag(Var->getLocation(), 3445 diag::err_typecheck_incomplete_array_needs_initializer); 3446 Var->setInvalidDecl(); 3447 return; 3448 } 3449 3450 // C++ [temp.expl.spec]p15: 3451 // An explicit specialization of a static data member of a template is a 3452 // definition if the declaration includes an initializer; otherwise, it 3453 // is a declaration. 3454 if (Var->isStaticDataMember() && 3455 Var->getInstantiatedFromStaticDataMember() && 3456 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3457 return; 3458 3459 // C++ [dcl.init]p9: 3460 // If no initializer is specified for an object, and the object 3461 // is of (possibly cv-qualified) non-POD class type (or array 3462 // thereof), the object shall be default-initialized; if the 3463 // object is of const-qualified type, the underlying class type 3464 // shall have a user-declared default constructor. 3465 // 3466 // FIXME: Diagnose the "user-declared default constructor" bit. 3467 if (getLangOptions().CPlusPlus) { 3468 QualType InitType = Type; 3469 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3470 InitType = Context.getBaseElementType(Array); 3471 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3472 InitType->isRecordType() && !InitType->isDependentType()) { 3473 if (!RequireCompleteType(Var->getLocation(), InitType, 3474 diag::err_invalid_incomplete_type_use)) { 3475 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3476 3477 CXXConstructorDecl *Constructor 3478 = PerformInitializationByConstructor(InitType, 3479 MultiExprArg(*this, 0, 0), 3480 Var->getLocation(), 3481 SourceRange(Var->getLocation(), 3482 Var->getLocation()), 3483 Var->getDeclName(), 3484 IK_Default, 3485 ConstructorArgs); 3486 3487 // FIXME: Location info for the variable initialization? 3488 if (!Constructor) 3489 Var->setInvalidDecl(); 3490 else { 3491 // FIXME: Cope with initialization of arrays 3492 if (!Constructor->isTrivial() && 3493 InitializeVarWithConstructor(Var, Constructor, 3494 move_arg(ConstructorArgs))) 3495 Var->setInvalidDecl(); 3496 3497 FinalizeVarWithDestructor(Var, InitType); 3498 } 3499 } else { 3500 Var->setInvalidDecl(); 3501 } 3502 } 3503 } 3504 3505#if 0 3506 // FIXME: Temporarily disabled because we are not properly parsing 3507 // linkage specifications on declarations, e.g., 3508 // 3509 // extern "C" const CGPoint CGPointerZero; 3510 // 3511 // C++ [dcl.init]p9: 3512 // 3513 // If no initializer is specified for an object, and the 3514 // object is of (possibly cv-qualified) non-POD class type (or 3515 // array thereof), the object shall be default-initialized; if 3516 // the object is of const-qualified type, the underlying class 3517 // type shall have a user-declared default 3518 // constructor. Otherwise, if no initializer is specified for 3519 // an object, the object and its subobjects, if any, have an 3520 // indeterminate initial value; if the object or any of its 3521 // subobjects are of const-qualified type, the program is 3522 // ill-formed. 3523 // 3524 // This isn't technically an error in C, so we don't diagnose it. 3525 // 3526 // FIXME: Actually perform the POD/user-defined default 3527 // constructor check. 3528 if (getLangOptions().CPlusPlus && 3529 Context.getCanonicalType(Type).isConstQualified() && 3530 !Var->hasExternalStorage()) 3531 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3532 << Var->getName() 3533 << SourceRange(Var->getLocation(), Var->getLocation()); 3534#endif 3535 } 3536} 3537 3538Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3539 DeclPtrTy *Group, 3540 unsigned NumDecls) { 3541 llvm::SmallVector<Decl*, 8> Decls; 3542 3543 if (DS.isTypeSpecOwned()) 3544 Decls.push_back((Decl*)DS.getTypeRep()); 3545 3546 for (unsigned i = 0; i != NumDecls; ++i) 3547 if (Decl *D = Group[i].getAs<Decl>()) 3548 Decls.push_back(D); 3549 3550 // Perform semantic analysis that depends on having fully processed both 3551 // the declarator and initializer. 3552 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3553 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3554 if (!IDecl) 3555 continue; 3556 QualType T = IDecl->getType(); 3557 3558 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3559 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3560 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3561 if (T->isDependentType()) { 3562 // If T is dependent, we should not require a complete type. 3563 // (RequireCompleteType shouldn't be called with dependent types.) 3564 // But we still can at least check if we've got an array of unspecified 3565 // size without an initializer. 3566 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3567 !IDecl->getInit()) { 3568 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3569 << T; 3570 IDecl->setInvalidDecl(); 3571 } 3572 } else if (!IDecl->isInvalidDecl()) { 3573 // If T is an incomplete array type with an initializer list that is 3574 // dependent on something, its size has not been fixed. We could attempt 3575 // to fix the size for such arrays, but we would still have to check 3576 // here for initializers containing a C++0x vararg expansion, e.g. 3577 // template <typename... Args> void f(Args... args) { 3578 // int vals[] = { args }; 3579 // } 3580 const IncompleteArrayType *IAT = T->getAs<IncompleteArrayType>(); 3581 Expr *Init = IDecl->getInit(); 3582 if (IAT && Init && 3583 (Init->isTypeDependent() || Init->isValueDependent())) { 3584 // Check that the member type of the array is complete, at least. 3585 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3586 diag::err_typecheck_decl_incomplete_type)) 3587 IDecl->setInvalidDecl(); 3588 } else if (RequireCompleteType(IDecl->getLocation(), T, 3589 diag::err_typecheck_decl_incomplete_type)) 3590 IDecl->setInvalidDecl(); 3591 } 3592 } 3593 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3594 // object that has file scope without an initializer, and without a 3595 // storage-class specifier or with the storage-class specifier "static", 3596 // constitutes a tentative definition. Note: A tentative definition with 3597 // external linkage is valid (C99 6.2.2p5). 3598 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3599 if (const IncompleteArrayType *ArrayT 3600 = Context.getAsIncompleteArrayType(T)) { 3601 if (RequireCompleteType(IDecl->getLocation(), 3602 ArrayT->getElementType(), 3603 diag::err_illegal_decl_array_incomplete_type)) 3604 IDecl->setInvalidDecl(); 3605 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3606 // C99 6.9.2p3: If the declaration of an identifier for an object is 3607 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3608 // declared type shall not be an incomplete type. 3609 // NOTE: code such as the following 3610 // static struct s; 3611 // struct s { int a; }; 3612 // is accepted by gcc. Hence here we issue a warning instead of 3613 // an error and we do not invalidate the static declaration. 3614 // NOTE: to avoid multiple warnings, only check the first declaration. 3615 if (IDecl->getPreviousDeclaration() == 0) 3616 RequireCompleteType(IDecl->getLocation(), T, 3617 diag::ext_typecheck_decl_incomplete_type); 3618 } 3619 } 3620 } 3621 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3622 Decls.data(), Decls.size())); 3623} 3624 3625 3626/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3627/// to introduce parameters into function prototype scope. 3628Sema::DeclPtrTy 3629Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3630 const DeclSpec &DS = D.getDeclSpec(); 3631 3632 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3633 VarDecl::StorageClass StorageClass = VarDecl::None; 3634 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3635 StorageClass = VarDecl::Register; 3636 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3637 Diag(DS.getStorageClassSpecLoc(), 3638 diag::err_invalid_storage_class_in_func_decl); 3639 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3640 } 3641 3642 if (D.getDeclSpec().isThreadSpecified()) 3643 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3644 3645 DiagnoseFunctionSpecifiers(D); 3646 3647 // Check that there are no default arguments inside the type of this 3648 // parameter (C++ only). 3649 if (getLangOptions().CPlusPlus) 3650 CheckExtraCXXDefaultArguments(D); 3651 3652 DeclaratorInfo *DInfo = 0; 3653 TagDecl *OwnedDecl = 0; 3654 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3655 3656 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3657 // C++ [dcl.fct]p6: 3658 // Types shall not be defined in return or parameter types. 3659 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3660 << Context.getTypeDeclType(OwnedDecl); 3661 } 3662 3663 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3664 // Can this happen for params? We already checked that they don't conflict 3665 // among each other. Here they can only shadow globals, which is ok. 3666 IdentifierInfo *II = D.getIdentifier(); 3667 if (II) { 3668 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3669 if (PrevDecl->isTemplateParameter()) { 3670 // Maybe we will complain about the shadowed template parameter. 3671 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3672 // Just pretend that we didn't see the previous declaration. 3673 PrevDecl = 0; 3674 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3675 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3676 3677 // Recover by removing the name 3678 II = 0; 3679 D.SetIdentifier(0, D.getIdentifierLoc()); 3680 } 3681 } 3682 } 3683 3684 // Parameters can not be abstract class types. 3685 // For record types, this is done by the AbstractClassUsageDiagnoser once 3686 // the class has been completely parsed. 3687 if (!CurContext->isRecord() && 3688 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3689 diag::err_abstract_type_in_decl, 3690 AbstractParamType)) 3691 D.setInvalidType(true); 3692 3693 QualType T = adjustParameterType(parmDeclType); 3694 3695 ParmVarDecl *New 3696 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3697 T, DInfo, StorageClass, 0); 3698 3699 if (D.isInvalidType()) 3700 New->setInvalidDecl(); 3701 3702 // Parameter declarators cannot be interface types. All ObjC objects are 3703 // passed by reference. 3704 if (T->isObjCInterfaceType()) { 3705 Diag(D.getIdentifierLoc(), 3706 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3707 New->setInvalidDecl(); 3708 } 3709 3710 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3711 if (D.getCXXScopeSpec().isSet()) { 3712 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3713 << D.getCXXScopeSpec().getRange(); 3714 New->setInvalidDecl(); 3715 } 3716 3717 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3718 // duration shall not be qualified by an address-space qualifier." 3719 // Since all parameters have automatic store duration, they can not have 3720 // an address space. 3721 if (T.getAddressSpace() != 0) { 3722 Diag(D.getIdentifierLoc(), 3723 diag::err_arg_with_address_space); 3724 New->setInvalidDecl(); 3725 } 3726 3727 3728 // Add the parameter declaration into this scope. 3729 S->AddDecl(DeclPtrTy::make(New)); 3730 if (II) 3731 IdResolver.AddDecl(New); 3732 3733 ProcessDeclAttributes(S, New, D); 3734 3735 if (New->hasAttr<BlocksAttr>()) { 3736 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3737 } 3738 return DeclPtrTy::make(New); 3739} 3740 3741void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3742 SourceLocation LocAfterDecls) { 3743 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3744 "Not a function declarator!"); 3745 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3746 3747 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3748 // for a K&R function. 3749 if (!FTI.hasPrototype) { 3750 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3751 --i; 3752 if (FTI.ArgInfo[i].Param == 0) { 3753 llvm::SmallString<256> Code; 3754 llvm::raw_svector_ostream(Code) << " int " 3755 << FTI.ArgInfo[i].Ident->getName() 3756 << ";\n"; 3757 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3758 << FTI.ArgInfo[i].Ident 3759 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3760 3761 // Implicitly declare the argument as type 'int' for lack of a better 3762 // type. 3763 DeclSpec DS; 3764 const char* PrevSpec; // unused 3765 unsigned DiagID; // unused 3766 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3767 PrevSpec, DiagID); 3768 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3769 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3770 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3771 } 3772 } 3773 } 3774} 3775 3776Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3777 Declarator &D) { 3778 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3779 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3780 "Not a function declarator!"); 3781 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3782 3783 if (FTI.hasPrototype) { 3784 // FIXME: Diagnose arguments without names in C. 3785 } 3786 3787 Scope *ParentScope = FnBodyScope->getParent(); 3788 3789 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3790 MultiTemplateParamsArg(*this), 3791 /*IsFunctionDefinition=*/true); 3792 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3793} 3794 3795Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3796 // Clear the last template instantiation error context. 3797 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 3798 3799 if (!D) 3800 return D; 3801 FunctionDecl *FD = 0; 3802 3803 if (FunctionTemplateDecl *FunTmpl 3804 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3805 FD = FunTmpl->getTemplatedDecl(); 3806 else 3807 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3808 3809 CurFunctionNeedsScopeChecking = false; 3810 3811 // See if this is a redefinition. 3812 const FunctionDecl *Definition; 3813 if (FD->getBody(Definition)) { 3814 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3815 Diag(Definition->getLocation(), diag::note_previous_definition); 3816 } 3817 3818 // Builtin functions cannot be defined. 3819 if (unsigned BuiltinID = FD->getBuiltinID()) { 3820 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3821 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3822 FD->setInvalidDecl(); 3823 } 3824 } 3825 3826 // The return type of a function definition must be complete 3827 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3828 QualType ResultType = FD->getResultType(); 3829 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3830 !FD->isInvalidDecl() && 3831 RequireCompleteType(FD->getLocation(), ResultType, 3832 diag::err_func_def_incomplete_result)) 3833 FD->setInvalidDecl(); 3834 3835 // GNU warning -Wmissing-prototypes: 3836 // Warn if a global function is defined without a previous 3837 // prototype declaration. This warning is issued even if the 3838 // definition itself provides a prototype. The aim is to detect 3839 // global functions that fail to be declared in header files. 3840 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3841 !FD->isMain()) { 3842 bool MissingPrototype = true; 3843 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3844 Prev; Prev = Prev->getPreviousDeclaration()) { 3845 // Ignore any declarations that occur in function or method 3846 // scope, because they aren't visible from the header. 3847 if (Prev->getDeclContext()->isFunctionOrMethod()) 3848 continue; 3849 3850 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3851 break; 3852 } 3853 3854 if (MissingPrototype) 3855 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3856 } 3857 3858 if (FnBodyScope) 3859 PushDeclContext(FnBodyScope, FD); 3860 3861 // Check the validity of our function parameters 3862 CheckParmsForFunctionDef(FD); 3863 3864 // Introduce our parameters into the function scope 3865 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3866 ParmVarDecl *Param = FD->getParamDecl(p); 3867 Param->setOwningFunction(FD); 3868 3869 // If this has an identifier, add it to the scope stack. 3870 if (Param->getIdentifier() && FnBodyScope) 3871 PushOnScopeChains(Param, FnBodyScope); 3872 } 3873 3874 // Checking attributes of current function definition 3875 // dllimport attribute. 3876 if (FD->getAttr<DLLImportAttr>() && 3877 (!FD->getAttr<DLLExportAttr>())) { 3878 // dllimport attribute cannot be applied to definition. 3879 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3880 Diag(FD->getLocation(), 3881 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3882 << "dllimport"; 3883 FD->setInvalidDecl(); 3884 return DeclPtrTy::make(FD); 3885 } else { 3886 // If a symbol previously declared dllimport is later defined, the 3887 // attribute is ignored in subsequent references, and a warning is 3888 // emitted. 3889 Diag(FD->getLocation(), 3890 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3891 << FD->getNameAsCString() << "dllimport"; 3892 } 3893 } 3894 return DeclPtrTy::make(FD); 3895} 3896 3897Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3898 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3899} 3900 3901Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3902 bool IsInstantiation) { 3903 Decl *dcl = D.getAs<Decl>(); 3904 Stmt *Body = BodyArg.takeAs<Stmt>(); 3905 3906 FunctionDecl *FD = 0; 3907 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3908 if (FunTmpl) 3909 FD = FunTmpl->getTemplatedDecl(); 3910 else 3911 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3912 3913 if (FD) { 3914 FD->setBody(Body); 3915 if (FD->isMain()) 3916 // C and C++ allow for main to automagically return 0. 3917 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3918 FD->setHasImplicitReturnZero(true); 3919 else 3920 CheckFallThroughForFunctionDef(FD, Body); 3921 3922 if (!FD->isInvalidDecl()) 3923 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3924 3925 // C++ [basic.def.odr]p2: 3926 // [...] A virtual member function is used if it is not pure. [...] 3927 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3928 if (Method->isVirtual() && !Method->isPure()) 3929 MarkDeclarationReferenced(Method->getLocation(), Method); 3930 3931 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3932 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3933 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3934 MD->setBody(Body); 3935 CheckFallThroughForFunctionDef(MD, Body); 3936 MD->setEndLoc(Body->getLocEnd()); 3937 3938 if (!MD->isInvalidDecl()) 3939 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3940 } else { 3941 Body->Destroy(Context); 3942 return DeclPtrTy(); 3943 } 3944 if (!IsInstantiation) 3945 PopDeclContext(); 3946 3947 // Verify and clean out per-function state. 3948 3949 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3950 3951 // Check goto/label use. 3952 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3953 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3954 LabelStmt *L = I->second; 3955 3956 // Verify that we have no forward references left. If so, there was a goto 3957 // or address of a label taken, but no definition of it. Label fwd 3958 // definitions are indicated with a null substmt. 3959 if (L->getSubStmt() != 0) 3960 continue; 3961 3962 // Emit error. 3963 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3964 3965 // At this point, we have gotos that use the bogus label. Stitch it into 3966 // the function body so that they aren't leaked and that the AST is well 3967 // formed. 3968 if (Body == 0) { 3969 // The whole function wasn't parsed correctly, just delete this. 3970 L->Destroy(Context); 3971 continue; 3972 } 3973 3974 // Otherwise, the body is valid: we want to stitch the label decl into the 3975 // function somewhere so that it is properly owned and so that the goto 3976 // has a valid target. Do this by creating a new compound stmt with the 3977 // label in it. 3978 3979 // Give the label a sub-statement. 3980 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3981 3982 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3983 cast<CXXTryStmt>(Body)->getTryBlock() : 3984 cast<CompoundStmt>(Body); 3985 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3986 Elements.push_back(L); 3987 Compound->setStmts(Context, &Elements[0], Elements.size()); 3988 } 3989 FunctionLabelMap.clear(); 3990 3991 if (!Body) return D; 3992 3993 // Verify that that gotos and switch cases don't jump into scopes illegally. 3994 if (CurFunctionNeedsScopeChecking) 3995 DiagnoseInvalidJumps(Body); 3996 3997 // C++ constructors that have function-try-blocks can't have return 3998 // statements in the handlers of that block. (C++ [except.handle]p14) 3999 // Verify this. 4000 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4001 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4002 4003 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4004 computeBaseOrMembersToDestroy(Destructor); 4005 return D; 4006} 4007 4008/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4009/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4010NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4011 IdentifierInfo &II, Scope *S) { 4012 // Before we produce a declaration for an implicitly defined 4013 // function, see whether there was a locally-scoped declaration of 4014 // this name as a function or variable. If so, use that 4015 // (non-visible) declaration, and complain about it. 4016 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4017 = LocallyScopedExternalDecls.find(&II); 4018 if (Pos != LocallyScopedExternalDecls.end()) { 4019 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4020 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4021 return Pos->second; 4022 } 4023 4024 // Extension in C99. Legal in C90, but warn about it. 4025 if (II.getName().startswith("__builtin_")) 4026 Diag(Loc, diag::warn_builtin_unknown) << &II; 4027 else if (getLangOptions().C99) 4028 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4029 else 4030 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4031 4032 // Set a Declarator for the implicit definition: int foo(); 4033 const char *Dummy; 4034 DeclSpec DS; 4035 unsigned DiagID; 4036 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4037 Error = Error; // Silence warning. 4038 assert(!Error && "Error setting up implicit decl!"); 4039 Declarator D(DS, Declarator::BlockContext); 4040 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4041 0, 0, false, SourceLocation(), 4042 false, 0,0,0, Loc, Loc, D), 4043 SourceLocation()); 4044 D.SetIdentifier(&II, Loc); 4045 4046 // Insert this function into translation-unit scope. 4047 4048 DeclContext *PrevDC = CurContext; 4049 CurContext = Context.getTranslationUnitDecl(); 4050 4051 FunctionDecl *FD = 4052 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4053 FD->setImplicit(); 4054 4055 CurContext = PrevDC; 4056 4057 AddKnownFunctionAttributes(FD); 4058 4059 return FD; 4060} 4061 4062/// \brief Adds any function attributes that we know a priori based on 4063/// the declaration of this function. 4064/// 4065/// These attributes can apply both to implicitly-declared builtins 4066/// (like __builtin___printf_chk) or to library-declared functions 4067/// like NSLog or printf. 4068void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4069 if (FD->isInvalidDecl()) 4070 return; 4071 4072 // If this is a built-in function, map its builtin attributes to 4073 // actual attributes. 4074 if (unsigned BuiltinID = FD->getBuiltinID()) { 4075 // Handle printf-formatting attributes. 4076 unsigned FormatIdx; 4077 bool HasVAListArg; 4078 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4079 if (!FD->getAttr<FormatAttr>()) 4080 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4081 HasVAListArg ? 0 : FormatIdx + 2)); 4082 } 4083 4084 // Mark const if we don't care about errno and that is the only 4085 // thing preventing the function from being const. This allows 4086 // IRgen to use LLVM intrinsics for such functions. 4087 if (!getLangOptions().MathErrno && 4088 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4089 if (!FD->getAttr<ConstAttr>()) 4090 FD->addAttr(::new (Context) ConstAttr()); 4091 } 4092 4093 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4094 FD->addAttr(::new (Context) NoReturnAttr()); 4095 } 4096 4097 IdentifierInfo *Name = FD->getIdentifier(); 4098 if (!Name) 4099 return; 4100 if ((!getLangOptions().CPlusPlus && 4101 FD->getDeclContext()->isTranslationUnit()) || 4102 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4103 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4104 LinkageSpecDecl::lang_c)) { 4105 // Okay: this could be a libc/libm/Objective-C function we know 4106 // about. 4107 } else 4108 return; 4109 4110 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4111 // FIXME: NSLog and NSLogv should be target specific 4112 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4113 // FIXME: We known better than our headers. 4114 const_cast<FormatAttr *>(Format)->setType("printf"); 4115 } else 4116 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4117 Name->isStr("NSLogv") ? 0 : 2)); 4118 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4119 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4120 // target-specific builtins, perhaps? 4121 if (!FD->getAttr<FormatAttr>()) 4122 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4123 Name->isStr("vasprintf") ? 0 : 3)); 4124 } 4125} 4126 4127TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4128 DeclaratorInfo *DInfo) { 4129 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4130 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4131 4132 if (!DInfo) { 4133 assert(D.isInvalidType() && "no declarator info for valid type"); 4134 DInfo = Context.getTrivialDeclaratorInfo(T); 4135 } 4136 4137 // Scope manipulation handled by caller. 4138 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4139 D.getIdentifierLoc(), 4140 D.getIdentifier(), 4141 DInfo); 4142 4143 if (const TagType *TT = T->getAs<TagType>()) { 4144 TagDecl *TD = TT->getDecl(); 4145 4146 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4147 // keep track of the TypedefDecl. 4148 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4149 TD->setTypedefForAnonDecl(NewTD); 4150 } 4151 4152 if (D.isInvalidType()) 4153 NewTD->setInvalidDecl(); 4154 return NewTD; 4155} 4156 4157 4158/// \brief Determine whether a tag with a given kind is acceptable 4159/// as a redeclaration of the given tag declaration. 4160/// 4161/// \returns true if the new tag kind is acceptable, false otherwise. 4162bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4163 TagDecl::TagKind NewTag, 4164 SourceLocation NewTagLoc, 4165 const IdentifierInfo &Name) { 4166 // C++ [dcl.type.elab]p3: 4167 // The class-key or enum keyword present in the 4168 // elaborated-type-specifier shall agree in kind with the 4169 // declaration to which the name in theelaborated-type-specifier 4170 // refers. This rule also applies to the form of 4171 // elaborated-type-specifier that declares a class-name or 4172 // friend class since it can be construed as referring to the 4173 // definition of the class. Thus, in any 4174 // elaborated-type-specifier, the enum keyword shall be used to 4175 // refer to an enumeration (7.2), the union class-keyshall be 4176 // used to refer to a union (clause 9), and either the class or 4177 // struct class-key shall be used to refer to a class (clause 9) 4178 // declared using the class or struct class-key. 4179 TagDecl::TagKind OldTag = Previous->getTagKind(); 4180 if (OldTag == NewTag) 4181 return true; 4182 4183 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4184 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4185 // Warn about the struct/class tag mismatch. 4186 bool isTemplate = false; 4187 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4188 isTemplate = Record->getDescribedClassTemplate(); 4189 4190 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4191 << (NewTag == TagDecl::TK_class) 4192 << isTemplate << &Name 4193 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4194 OldTag == TagDecl::TK_class? "class" : "struct"); 4195 Diag(Previous->getLocation(), diag::note_previous_use); 4196 return true; 4197 } 4198 return false; 4199} 4200 4201/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4202/// former case, Name will be non-null. In the later case, Name will be null. 4203/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4204/// reference/declaration/definition of a tag. 4205Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4206 SourceLocation KWLoc, const CXXScopeSpec &SS, 4207 IdentifierInfo *Name, SourceLocation NameLoc, 4208 AttributeList *Attr, AccessSpecifier AS, 4209 MultiTemplateParamsArg TemplateParameterLists, 4210 bool &OwnedDecl, bool &IsDependent) { 4211 // If this is not a definition, it must have a name. 4212 assert((Name != 0 || TUK == TUK_Definition) && 4213 "Nameless record must be a definition!"); 4214 4215 OwnedDecl = false; 4216 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4217 4218 // FIXME: Check explicit specializations more carefully. 4219 bool isExplicitSpecialization = false; 4220 if (TUK != TUK_Reference) { 4221 if (TemplateParameterList *TemplateParams 4222 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4223 (TemplateParameterList**)TemplateParameterLists.get(), 4224 TemplateParameterLists.size(), 4225 isExplicitSpecialization)) { 4226 if (TemplateParams->size() > 0) { 4227 // This is a declaration or definition of a class template (which may 4228 // be a member of another template). 4229 OwnedDecl = false; 4230 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4231 SS, Name, NameLoc, Attr, 4232 TemplateParams, 4233 AS); 4234 TemplateParameterLists.release(); 4235 return Result.get(); 4236 } else { 4237 // The "template<>" header is extraneous. 4238 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4239 << ElaboratedType::getNameForTagKind(Kind) << Name; 4240 isExplicitSpecialization = true; 4241 } 4242 } 4243 4244 TemplateParameterLists.release(); 4245 } 4246 4247 DeclContext *SearchDC = CurContext; 4248 DeclContext *DC = CurContext; 4249 NamedDecl *PrevDecl = 0; 4250 bool isStdBadAlloc = false; 4251 bool Invalid = false; 4252 4253 bool RedeclarationOnly = (TUK != TUK_Reference); 4254 4255 if (Name && SS.isNotEmpty()) { 4256 // We have a nested-name tag ('struct foo::bar'). 4257 4258 // Check for invalid 'foo::'. 4259 if (SS.isInvalid()) { 4260 Name = 0; 4261 goto CreateNewDecl; 4262 } 4263 4264 // If this is a friend or a reference to a class in a dependent 4265 // context, don't try to make a decl for it. 4266 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4267 DC = computeDeclContext(SS, false); 4268 if (!DC) { 4269 IsDependent = true; 4270 return DeclPtrTy(); 4271 } 4272 } 4273 4274 if (RequireCompleteDeclContext(SS)) 4275 return DeclPtrTy::make((Decl *)0); 4276 4277 DC = computeDeclContext(SS, true); 4278 SearchDC = DC; 4279 // Look-up name inside 'foo::'. 4280 LookupResult R; 4281 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4282 4283 if (R.isAmbiguous()) { 4284 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4285 return DeclPtrTy(); 4286 } 4287 4288 if (R.getKind() == LookupResult::Found) 4289 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4290 4291 // A tag 'foo::bar' must already exist. 4292 if (!PrevDecl) { 4293 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4294 Name = 0; 4295 Invalid = true; 4296 goto CreateNewDecl; 4297 } 4298 } else if (Name) { 4299 // If this is a named struct, check to see if there was a previous forward 4300 // declaration or definition. 4301 // FIXME: We're looking into outer scopes here, even when we 4302 // shouldn't be. Doing so can result in ambiguities that we 4303 // shouldn't be diagnosing. 4304 LookupResult R; 4305 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4306 if (R.isAmbiguous()) { 4307 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4308 // FIXME: This is not best way to recover from case like: 4309 // 4310 // struct S s; 4311 // 4312 // causes needless "incomplete type" error later. 4313 Name = 0; 4314 PrevDecl = 0; 4315 Invalid = true; 4316 } else 4317 PrevDecl = R.getAsSingleDecl(Context); 4318 4319 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4320 // FIXME: This makes sure that we ignore the contexts associated 4321 // with C structs, unions, and enums when looking for a matching 4322 // tag declaration or definition. See the similar lookup tweak 4323 // in Sema::LookupName; is there a better way to deal with this? 4324 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4325 SearchDC = SearchDC->getParent(); 4326 } 4327 } 4328 4329 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4330 // Maybe we will complain about the shadowed template parameter. 4331 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4332 // Just pretend that we didn't see the previous declaration. 4333 PrevDecl = 0; 4334 } 4335 4336 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4337 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4338 // This is a declaration of or a reference to "std::bad_alloc". 4339 isStdBadAlloc = true; 4340 4341 if (!PrevDecl && StdBadAlloc) { 4342 // std::bad_alloc has been implicitly declared (but made invisible to 4343 // name lookup). Fill in this implicit declaration as the previous 4344 // declaration, so that the declarations get chained appropriately. 4345 PrevDecl = StdBadAlloc; 4346 } 4347 } 4348 4349 if (PrevDecl) { 4350 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4351 // If this is a use of a previous tag, or if the tag is already declared 4352 // in the same scope (so that the definition/declaration completes or 4353 // rementions the tag), reuse the decl. 4354 if (TUK == TUK_Reference || TUK == TUK_Friend || 4355 isDeclInScope(PrevDecl, SearchDC, S)) { 4356 // Make sure that this wasn't declared as an enum and now used as a 4357 // struct or something similar. 4358 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4359 bool SafeToContinue 4360 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4361 Kind != TagDecl::TK_enum); 4362 if (SafeToContinue) 4363 Diag(KWLoc, diag::err_use_with_wrong_tag) 4364 << Name 4365 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4366 PrevTagDecl->getKindName()); 4367 else 4368 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4369 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4370 4371 if (SafeToContinue) 4372 Kind = PrevTagDecl->getTagKind(); 4373 else { 4374 // Recover by making this an anonymous redefinition. 4375 Name = 0; 4376 PrevDecl = 0; 4377 Invalid = true; 4378 } 4379 } 4380 4381 if (!Invalid) { 4382 // If this is a use, just return the declaration we found. 4383 4384 // FIXME: In the future, return a variant or some other clue 4385 // for the consumer of this Decl to know it doesn't own it. 4386 // For our current ASTs this shouldn't be a problem, but will 4387 // need to be changed with DeclGroups. 4388 if (TUK == TUK_Reference || TUK == TUK_Friend) 4389 return DeclPtrTy::make(PrevDecl); 4390 4391 // Diagnose attempts to redefine a tag. 4392 if (TUK == TUK_Definition) { 4393 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4394 // If we're defining a specialization and the previous definition 4395 // is from an implicit instantiation, don't emit an error 4396 // here; we'll catch this in the general case below. 4397 if (!isExplicitSpecialization || 4398 !isa<CXXRecordDecl>(Def) || 4399 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4400 == TSK_ExplicitSpecialization) { 4401 Diag(NameLoc, diag::err_redefinition) << Name; 4402 Diag(Def->getLocation(), diag::note_previous_definition); 4403 // If this is a redefinition, recover by making this 4404 // struct be anonymous, which will make any later 4405 // references get the previous definition. 4406 Name = 0; 4407 PrevDecl = 0; 4408 Invalid = true; 4409 } 4410 } else { 4411 // If the type is currently being defined, complain 4412 // about a nested redefinition. 4413 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4414 if (Tag->isBeingDefined()) { 4415 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4416 Diag(PrevTagDecl->getLocation(), 4417 diag::note_previous_definition); 4418 Name = 0; 4419 PrevDecl = 0; 4420 Invalid = true; 4421 } 4422 } 4423 4424 // Okay, this is definition of a previously declared or referenced 4425 // tag PrevDecl. We're going to create a new Decl for it. 4426 } 4427 } 4428 // If we get here we have (another) forward declaration or we 4429 // have a definition. Just create a new decl. 4430 4431 } else { 4432 // If we get here, this is a definition of a new tag type in a nested 4433 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4434 // new decl/type. We set PrevDecl to NULL so that the entities 4435 // have distinct types. 4436 PrevDecl = 0; 4437 } 4438 // If we get here, we're going to create a new Decl. If PrevDecl 4439 // is non-NULL, it's a definition of the tag declared by 4440 // PrevDecl. If it's NULL, we have a new definition. 4441 } else { 4442 // PrevDecl is a namespace, template, or anything else 4443 // that lives in the IDNS_Tag identifier namespace. 4444 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4445 // The tag name clashes with a namespace name, issue an error and 4446 // recover by making this tag be anonymous. 4447 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4448 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4449 Name = 0; 4450 PrevDecl = 0; 4451 Invalid = true; 4452 } else { 4453 // The existing declaration isn't relevant to us; we're in a 4454 // new scope, so clear out the previous declaration. 4455 PrevDecl = 0; 4456 } 4457 } 4458 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4459 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4460 // C++ [basic.scope.pdecl]p5: 4461 // -- for an elaborated-type-specifier of the form 4462 // 4463 // class-key identifier 4464 // 4465 // if the elaborated-type-specifier is used in the 4466 // decl-specifier-seq or parameter-declaration-clause of a 4467 // function defined in namespace scope, the identifier is 4468 // declared as a class-name in the namespace that contains 4469 // the declaration; otherwise, except as a friend 4470 // declaration, the identifier is declared in the smallest 4471 // non-class, non-function-prototype scope that contains the 4472 // declaration. 4473 // 4474 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4475 // C structs and unions. 4476 // 4477 // GNU C also supports this behavior as part of its incomplete 4478 // enum types extension, while GNU C++ does not. 4479 // 4480 // Find the context where we'll be declaring the tag. 4481 // FIXME: We would like to maintain the current DeclContext as the 4482 // lexical context, 4483 while (SearchDC->isRecord()) 4484 SearchDC = SearchDC->getParent(); 4485 4486 // Find the scope where we'll be declaring the tag. 4487 while (S->isClassScope() || 4488 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4489 ((S->getFlags() & Scope::DeclScope) == 0) || 4490 (S->getEntity() && 4491 ((DeclContext *)S->getEntity())->isTransparentContext())) 4492 S = S->getParent(); 4493 4494 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4495 // C++ [namespace.memdef]p3: 4496 // If a friend declaration in a non-local class first declares a 4497 // class or function, the friend class or function is a member of 4498 // the innermost enclosing namespace. 4499 while (!SearchDC->isFileContext()) 4500 SearchDC = SearchDC->getParent(); 4501 4502 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4503 while (S->getEntity() != SearchDC) 4504 S = S->getParent(); 4505 } 4506 4507CreateNewDecl: 4508 4509 // If there is an identifier, use the location of the identifier as the 4510 // location of the decl, otherwise use the location of the struct/union 4511 // keyword. 4512 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4513 4514 // Otherwise, create a new declaration. If there is a previous 4515 // declaration of the same entity, the two will be linked via 4516 // PrevDecl. 4517 TagDecl *New; 4518 4519 if (Kind == TagDecl::TK_enum) { 4520 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4521 // enum X { A, B, C } D; D should chain to X. 4522 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4523 cast_or_null<EnumDecl>(PrevDecl)); 4524 // If this is an undefined enum, warn. 4525 if (TUK != TUK_Definition && !Invalid) { 4526 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4527 : diag::ext_forward_ref_enum; 4528 Diag(Loc, DK); 4529 } 4530 } else { 4531 // struct/union/class 4532 4533 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4534 // struct X { int A; } D; D should chain to X. 4535 if (getLangOptions().CPlusPlus) { 4536 // FIXME: Look for a way to use RecordDecl for simple structs. 4537 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4538 cast_or_null<CXXRecordDecl>(PrevDecl)); 4539 4540 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4541 StdBadAlloc = cast<CXXRecordDecl>(New); 4542 } else 4543 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4544 cast_or_null<RecordDecl>(PrevDecl)); 4545 } 4546 4547 if (Kind != TagDecl::TK_enum) { 4548 // Handle #pragma pack: if the #pragma pack stack has non-default 4549 // alignment, make up a packed attribute for this decl. These 4550 // attributes are checked when the ASTContext lays out the 4551 // structure. 4552 // 4553 // It is important for implementing the correct semantics that this 4554 // happen here (in act on tag decl). The #pragma pack stack is 4555 // maintained as a result of parser callbacks which can occur at 4556 // many points during the parsing of a struct declaration (because 4557 // the #pragma tokens are effectively skipped over during the 4558 // parsing of the struct). 4559 if (unsigned Alignment = getPragmaPackAlignment()) 4560 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4561 } 4562 4563 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4564 // C++ [dcl.typedef]p3: 4565 // [...] Similarly, in a given scope, a class or enumeration 4566 // shall not be declared with the same name as a typedef-name 4567 // that is declared in that scope and refers to a type other 4568 // than the class or enumeration itself. 4569 LookupResult Lookup; 4570 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4571 TypedefDecl *PrevTypedef = 0; 4572 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4573 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4574 4575 NamedDecl *PrevTypedefNamed = PrevTypedef; 4576 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4577 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4578 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4579 Diag(Loc, diag::err_tag_definition_of_typedef) 4580 << Context.getTypeDeclType(New) 4581 << PrevTypedef->getUnderlyingType(); 4582 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4583 Invalid = true; 4584 } 4585 } 4586 4587 // If this is a specialization of a member class (of a class template), 4588 // check the specialization. 4589 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4590 Invalid = true; 4591 4592 if (Invalid) 4593 New->setInvalidDecl(); 4594 4595 if (Attr) 4596 ProcessDeclAttributeList(S, New, Attr); 4597 4598 // If we're declaring or defining a tag in function prototype scope 4599 // in C, note that this type can only be used within the function. 4600 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4601 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4602 4603 // Set the lexical context. If the tag has a C++ scope specifier, the 4604 // lexical context will be different from the semantic context. 4605 New->setLexicalDeclContext(CurContext); 4606 4607 // Mark this as a friend decl if applicable. 4608 if (TUK == TUK_Friend) 4609 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4610 4611 // Set the access specifier. 4612 if (!Invalid && TUK != TUK_Friend) 4613 SetMemberAccessSpecifier(New, PrevDecl, AS); 4614 4615 if (TUK == TUK_Definition) 4616 New->startDefinition(); 4617 4618 // If this has an identifier, add it to the scope stack. 4619 if (TUK == TUK_Friend) { 4620 // We might be replacing an existing declaration in the lookup tables; 4621 // if so, borrow its access specifier. 4622 if (PrevDecl) 4623 New->setAccess(PrevDecl->getAccess()); 4624 4625 // Friend tag decls are visible in fairly strange ways. 4626 if (!CurContext->isDependentContext()) { 4627 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4628 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4629 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4630 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4631 } 4632 } else if (Name) { 4633 S = getNonFieldDeclScope(S); 4634 PushOnScopeChains(New, S); 4635 } else { 4636 CurContext->addDecl(New); 4637 } 4638 4639 // If this is the C FILE type, notify the AST context. 4640 if (IdentifierInfo *II = New->getIdentifier()) 4641 if (!New->isInvalidDecl() && 4642 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4643 II->isStr("FILE")) 4644 Context.setFILEDecl(New); 4645 4646 OwnedDecl = true; 4647 return DeclPtrTy::make(New); 4648} 4649 4650void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4651 AdjustDeclIfTemplate(TagD); 4652 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4653 4654 // Enter the tag context. 4655 PushDeclContext(S, Tag); 4656 4657 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4658 FieldCollector->StartClass(); 4659 4660 if (Record->getIdentifier()) { 4661 // C++ [class]p2: 4662 // [...] The class-name is also inserted into the scope of the 4663 // class itself; this is known as the injected-class-name. For 4664 // purposes of access checking, the injected-class-name is treated 4665 // as if it were a public member name. 4666 CXXRecordDecl *InjectedClassName 4667 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4668 CurContext, Record->getLocation(), 4669 Record->getIdentifier(), 4670 Record->getTagKeywordLoc(), 4671 Record); 4672 InjectedClassName->setImplicit(); 4673 InjectedClassName->setAccess(AS_public); 4674 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4675 InjectedClassName->setDescribedClassTemplate(Template); 4676 PushOnScopeChains(InjectedClassName, S); 4677 assert(InjectedClassName->isInjectedClassName() && 4678 "Broken injected-class-name"); 4679 } 4680 } 4681} 4682 4683void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4684 SourceLocation RBraceLoc) { 4685 AdjustDeclIfTemplate(TagD); 4686 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4687 Tag->setRBraceLoc(RBraceLoc); 4688 4689 if (isa<CXXRecordDecl>(Tag)) 4690 FieldCollector->FinishClass(); 4691 4692 // Exit this scope of this tag's definition. 4693 PopDeclContext(); 4694 4695 // Notify the consumer that we've defined a tag. 4696 Consumer.HandleTagDeclDefinition(Tag); 4697} 4698 4699// Note that FieldName may be null for anonymous bitfields. 4700bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4701 QualType FieldTy, const Expr *BitWidth, 4702 bool *ZeroWidth) { 4703 // Default to true; that shouldn't confuse checks for emptiness 4704 if (ZeroWidth) 4705 *ZeroWidth = true; 4706 4707 // C99 6.7.2.1p4 - verify the field type. 4708 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4709 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4710 // Handle incomplete types with specific error. 4711 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4712 return true; 4713 if (FieldName) 4714 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4715 << FieldName << FieldTy << BitWidth->getSourceRange(); 4716 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4717 << FieldTy << BitWidth->getSourceRange(); 4718 } 4719 4720 // If the bit-width is type- or value-dependent, don't try to check 4721 // it now. 4722 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4723 return false; 4724 4725 llvm::APSInt Value; 4726 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4727 return true; 4728 4729 if (Value != 0 && ZeroWidth) 4730 *ZeroWidth = false; 4731 4732 // Zero-width bitfield is ok for anonymous field. 4733 if (Value == 0 && FieldName) 4734 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4735 4736 if (Value.isSigned() && Value.isNegative()) { 4737 if (FieldName) 4738 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4739 << FieldName << Value.toString(10); 4740 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4741 << Value.toString(10); 4742 } 4743 4744 if (!FieldTy->isDependentType()) { 4745 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4746 if (Value.getZExtValue() > TypeSize) { 4747 if (FieldName) 4748 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4749 << FieldName << (unsigned)TypeSize; 4750 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4751 << (unsigned)TypeSize; 4752 } 4753 } 4754 4755 return false; 4756} 4757 4758/// ActOnField - Each field of a struct/union/class is passed into this in order 4759/// to create a FieldDecl object for it. 4760Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4761 SourceLocation DeclStart, 4762 Declarator &D, ExprTy *BitfieldWidth) { 4763 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4764 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4765 AS_public); 4766 return DeclPtrTy::make(Res); 4767} 4768 4769/// HandleField - Analyze a field of a C struct or a C++ data member. 4770/// 4771FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4772 SourceLocation DeclStart, 4773 Declarator &D, Expr *BitWidth, 4774 AccessSpecifier AS) { 4775 IdentifierInfo *II = D.getIdentifier(); 4776 SourceLocation Loc = DeclStart; 4777 if (II) Loc = D.getIdentifierLoc(); 4778 4779 DeclaratorInfo *DInfo = 0; 4780 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4781 if (getLangOptions().CPlusPlus) 4782 CheckExtraCXXDefaultArguments(D); 4783 4784 DiagnoseFunctionSpecifiers(D); 4785 4786 if (D.getDeclSpec().isThreadSpecified()) 4787 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4788 4789 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4790 4791 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4792 // Maybe we will complain about the shadowed template parameter. 4793 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4794 // Just pretend that we didn't see the previous declaration. 4795 PrevDecl = 0; 4796 } 4797 4798 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4799 PrevDecl = 0; 4800 4801 bool Mutable 4802 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4803 SourceLocation TSSL = D.getSourceRange().getBegin(); 4804 FieldDecl *NewFD 4805 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4806 AS, PrevDecl, &D); 4807 if (NewFD->isInvalidDecl() && PrevDecl) { 4808 // Don't introduce NewFD into scope; there's already something 4809 // with the same name in the same scope. 4810 } else if (II) { 4811 PushOnScopeChains(NewFD, S); 4812 } else 4813 Record->addDecl(NewFD); 4814 4815 return NewFD; 4816} 4817 4818/// \brief Build a new FieldDecl and check its well-formedness. 4819/// 4820/// This routine builds a new FieldDecl given the fields name, type, 4821/// record, etc. \p PrevDecl should refer to any previous declaration 4822/// with the same name and in the same scope as the field to be 4823/// created. 4824/// 4825/// \returns a new FieldDecl. 4826/// 4827/// \todo The Declarator argument is a hack. It will be removed once 4828FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4829 DeclaratorInfo *DInfo, 4830 RecordDecl *Record, SourceLocation Loc, 4831 bool Mutable, Expr *BitWidth, 4832 SourceLocation TSSL, 4833 AccessSpecifier AS, NamedDecl *PrevDecl, 4834 Declarator *D) { 4835 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4836 bool InvalidDecl = false; 4837 if (D) InvalidDecl = D->isInvalidType(); 4838 4839 // If we receive a broken type, recover by assuming 'int' and 4840 // marking this declaration as invalid. 4841 if (T.isNull()) { 4842 InvalidDecl = true; 4843 T = Context.IntTy; 4844 } 4845 4846 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4847 // than a variably modified type. 4848 if (T->isVariablyModifiedType()) { 4849 bool SizeIsNegative; 4850 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4851 SizeIsNegative); 4852 if (!FixedTy.isNull()) { 4853 Diag(Loc, diag::warn_illegal_constant_array_size); 4854 T = FixedTy; 4855 } else { 4856 if (SizeIsNegative) 4857 Diag(Loc, diag::err_typecheck_negative_array_size); 4858 else 4859 Diag(Loc, diag::err_typecheck_field_variable_size); 4860 InvalidDecl = true; 4861 } 4862 } 4863 4864 // Fields can not have abstract class types 4865 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4866 AbstractFieldType)) 4867 InvalidDecl = true; 4868 4869 bool ZeroWidth = false; 4870 // If this is declared as a bit-field, check the bit-field. 4871 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4872 InvalidDecl = true; 4873 DeleteExpr(BitWidth); 4874 BitWidth = 0; 4875 ZeroWidth = false; 4876 } 4877 4878 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4879 BitWidth, Mutable); 4880 if (InvalidDecl) 4881 NewFD->setInvalidDecl(); 4882 4883 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4884 Diag(Loc, diag::err_duplicate_member) << II; 4885 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4886 NewFD->setInvalidDecl(); 4887 } 4888 4889 if (getLangOptions().CPlusPlus) { 4890 QualType EltTy = Context.getBaseElementType(T); 4891 4892 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4893 4894 if (!T->isPODType()) 4895 CXXRecord->setPOD(false); 4896 if (!ZeroWidth) 4897 CXXRecord->setEmpty(false); 4898 4899 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4900 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4901 4902 if (!RDecl->hasTrivialConstructor()) 4903 CXXRecord->setHasTrivialConstructor(false); 4904 if (!RDecl->hasTrivialCopyConstructor()) 4905 CXXRecord->setHasTrivialCopyConstructor(false); 4906 if (!RDecl->hasTrivialCopyAssignment()) 4907 CXXRecord->setHasTrivialCopyAssignment(false); 4908 if (!RDecl->hasTrivialDestructor()) 4909 CXXRecord->setHasTrivialDestructor(false); 4910 4911 // C++ 9.5p1: An object of a class with a non-trivial 4912 // constructor, a non-trivial copy constructor, a non-trivial 4913 // destructor, or a non-trivial copy assignment operator 4914 // cannot be a member of a union, nor can an array of such 4915 // objects. 4916 // TODO: C++0x alters this restriction significantly. 4917 if (Record->isUnion()) { 4918 // We check for copy constructors before constructors 4919 // because otherwise we'll never get complaints about 4920 // copy constructors. 4921 4922 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4923 4924 CXXSpecialMember member; 4925 if (!RDecl->hasTrivialCopyConstructor()) 4926 member = CXXCopyConstructor; 4927 else if (!RDecl->hasTrivialConstructor()) 4928 member = CXXDefaultConstructor; 4929 else if (!RDecl->hasTrivialCopyAssignment()) 4930 member = CXXCopyAssignment; 4931 else if (!RDecl->hasTrivialDestructor()) 4932 member = CXXDestructor; 4933 else 4934 member = invalid; 4935 4936 if (member != invalid) { 4937 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4938 DiagnoseNontrivial(RT, member); 4939 NewFD->setInvalidDecl(); 4940 } 4941 } 4942 } 4943 } 4944 4945 // FIXME: We need to pass in the attributes given an AST 4946 // representation, not a parser representation. 4947 if (D) 4948 // FIXME: What to pass instead of TUScope? 4949 ProcessDeclAttributes(TUScope, NewFD, *D); 4950 4951 if (T.isObjCGCWeak()) 4952 Diag(Loc, diag::warn_attribute_weak_on_field); 4953 4954 NewFD->setAccess(AS); 4955 4956 // C++ [dcl.init.aggr]p1: 4957 // An aggregate is an array or a class (clause 9) with [...] no 4958 // private or protected non-static data members (clause 11). 4959 // A POD must be an aggregate. 4960 if (getLangOptions().CPlusPlus && 4961 (AS == AS_private || AS == AS_protected)) { 4962 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4963 CXXRecord->setAggregate(false); 4964 CXXRecord->setPOD(false); 4965 } 4966 4967 return NewFD; 4968} 4969 4970/// DiagnoseNontrivial - Given that a class has a non-trivial 4971/// special member, figure out why. 4972void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4973 QualType QT(T, 0U); 4974 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4975 4976 // Check whether the member was user-declared. 4977 switch (member) { 4978 case CXXDefaultConstructor: 4979 if (RD->hasUserDeclaredConstructor()) { 4980 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4981 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 4982 const FunctionDecl *body = 0; 4983 ci->getBody(body); 4984 if (!body || 4985 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 4986 SourceLocation CtorLoc = ci->getLocation(); 4987 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4988 return; 4989 } 4990 } 4991 4992 assert(0 && "found no user-declared constructors"); 4993 return; 4994 } 4995 break; 4996 4997 case CXXCopyConstructor: 4998 if (RD->hasUserDeclaredCopyConstructor()) { 4999 SourceLocation CtorLoc = 5000 RD->getCopyConstructor(Context, 0)->getLocation(); 5001 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5002 return; 5003 } 5004 break; 5005 5006 case CXXCopyAssignment: 5007 if (RD->hasUserDeclaredCopyAssignment()) { 5008 // FIXME: this should use the location of the copy 5009 // assignment, not the type. 5010 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5011 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5012 return; 5013 } 5014 break; 5015 5016 case CXXDestructor: 5017 if (RD->hasUserDeclaredDestructor()) { 5018 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5019 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5020 return; 5021 } 5022 break; 5023 } 5024 5025 typedef CXXRecordDecl::base_class_iterator base_iter; 5026 5027 // Virtual bases and members inhibit trivial copying/construction, 5028 // but not trivial destruction. 5029 if (member != CXXDestructor) { 5030 // Check for virtual bases. vbases includes indirect virtual bases, 5031 // so we just iterate through the direct bases. 5032 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5033 if (bi->isVirtual()) { 5034 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5035 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5036 return; 5037 } 5038 5039 // Check for virtual methods. 5040 typedef CXXRecordDecl::method_iterator meth_iter; 5041 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5042 ++mi) { 5043 if (mi->isVirtual()) { 5044 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5045 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5046 return; 5047 } 5048 } 5049 } 5050 5051 bool (CXXRecordDecl::*hasTrivial)() const; 5052 switch (member) { 5053 case CXXDefaultConstructor: 5054 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5055 case CXXCopyConstructor: 5056 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5057 case CXXCopyAssignment: 5058 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5059 case CXXDestructor: 5060 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5061 default: 5062 assert(0 && "unexpected special member"); return; 5063 } 5064 5065 // Check for nontrivial bases (and recurse). 5066 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5067 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5068 assert(BaseRT && "Don't know how to handle dependent bases"); 5069 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5070 if (!(BaseRecTy->*hasTrivial)()) { 5071 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5072 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5073 DiagnoseNontrivial(BaseRT, member); 5074 return; 5075 } 5076 } 5077 5078 // Check for nontrivial members (and recurse). 5079 typedef RecordDecl::field_iterator field_iter; 5080 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5081 ++fi) { 5082 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5083 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5084 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5085 5086 if (!(EltRD->*hasTrivial)()) { 5087 SourceLocation FLoc = (*fi)->getLocation(); 5088 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5089 DiagnoseNontrivial(EltRT, member); 5090 return; 5091 } 5092 } 5093 } 5094 5095 assert(0 && "found no explanation for non-trivial member"); 5096} 5097 5098/// TranslateIvarVisibility - Translate visibility from a token ID to an 5099/// AST enum value. 5100static ObjCIvarDecl::AccessControl 5101TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5102 switch (ivarVisibility) { 5103 default: assert(0 && "Unknown visitibility kind"); 5104 case tok::objc_private: return ObjCIvarDecl::Private; 5105 case tok::objc_public: return ObjCIvarDecl::Public; 5106 case tok::objc_protected: return ObjCIvarDecl::Protected; 5107 case tok::objc_package: return ObjCIvarDecl::Package; 5108 } 5109} 5110 5111/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5112/// in order to create an IvarDecl object for it. 5113Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5114 SourceLocation DeclStart, 5115 DeclPtrTy IntfDecl, 5116 Declarator &D, ExprTy *BitfieldWidth, 5117 tok::ObjCKeywordKind Visibility) { 5118 5119 IdentifierInfo *II = D.getIdentifier(); 5120 Expr *BitWidth = (Expr*)BitfieldWidth; 5121 SourceLocation Loc = DeclStart; 5122 if (II) Loc = D.getIdentifierLoc(); 5123 5124 // FIXME: Unnamed fields can be handled in various different ways, for 5125 // example, unnamed unions inject all members into the struct namespace! 5126 5127 DeclaratorInfo *DInfo = 0; 5128 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5129 5130 if (BitWidth) { 5131 // 6.7.2.1p3, 6.7.2.1p4 5132 if (VerifyBitField(Loc, II, T, BitWidth)) { 5133 D.setInvalidType(); 5134 DeleteExpr(BitWidth); 5135 BitWidth = 0; 5136 } 5137 } else { 5138 // Not a bitfield. 5139 5140 // validate II. 5141 5142 } 5143 5144 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5145 // than a variably modified type. 5146 if (T->isVariablyModifiedType()) { 5147 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5148 D.setInvalidType(); 5149 } 5150 5151 // Get the visibility (access control) for this ivar. 5152 ObjCIvarDecl::AccessControl ac = 5153 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5154 : ObjCIvarDecl::None; 5155 // Must set ivar's DeclContext to its enclosing interface. 5156 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5157 DeclContext *EnclosingContext; 5158 if (ObjCImplementationDecl *IMPDecl = 5159 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5160 // Case of ivar declared in an implementation. Context is that of its class. 5161 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5162 assert(IDecl && "No class- ActOnIvar"); 5163 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5164 } else 5165 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5166 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5167 5168 // Construct the decl. 5169 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5170 EnclosingContext, Loc, II, T, 5171 DInfo, ac, (Expr *)BitfieldWidth); 5172 5173 if (II) { 5174 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5175 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5176 && !isa<TagDecl>(PrevDecl)) { 5177 Diag(Loc, diag::err_duplicate_member) << II; 5178 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5179 NewID->setInvalidDecl(); 5180 } 5181 } 5182 5183 // Process attributes attached to the ivar. 5184 ProcessDeclAttributes(S, NewID, D); 5185 5186 if (D.isInvalidType()) 5187 NewID->setInvalidDecl(); 5188 5189 if (II) { 5190 // FIXME: When interfaces are DeclContexts, we'll need to add 5191 // these to the interface. 5192 S->AddDecl(DeclPtrTy::make(NewID)); 5193 IdResolver.AddDecl(NewID); 5194 } 5195 5196 return DeclPtrTy::make(NewID); 5197} 5198 5199void Sema::ActOnFields(Scope* S, 5200 SourceLocation RecLoc, DeclPtrTy RecDecl, 5201 DeclPtrTy *Fields, unsigned NumFields, 5202 SourceLocation LBrac, SourceLocation RBrac, 5203 AttributeList *Attr) { 5204 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5205 assert(EnclosingDecl && "missing record or interface decl"); 5206 5207 // If the decl this is being inserted into is invalid, then it may be a 5208 // redeclaration or some other bogus case. Don't try to add fields to it. 5209 if (EnclosingDecl->isInvalidDecl()) { 5210 // FIXME: Deallocate fields? 5211 return; 5212 } 5213 5214 5215 // Verify that all the fields are okay. 5216 unsigned NumNamedMembers = 0; 5217 llvm::SmallVector<FieldDecl*, 32> RecFields; 5218 5219 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5220 for (unsigned i = 0; i != NumFields; ++i) { 5221 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5222 5223 // Get the type for the field. 5224 Type *FDTy = FD->getType().getTypePtr(); 5225 5226 if (!FD->isAnonymousStructOrUnion()) { 5227 // Remember all fields written by the user. 5228 RecFields.push_back(FD); 5229 } 5230 5231 // If the field is already invalid for some reason, don't emit more 5232 // diagnostics about it. 5233 if (FD->isInvalidDecl()) 5234 continue; 5235 5236 // C99 6.7.2.1p2: 5237 // A structure or union shall not contain a member with 5238 // incomplete or function type (hence, a structure shall not 5239 // contain an instance of itself, but may contain a pointer to 5240 // an instance of itself), except that the last member of a 5241 // structure with more than one named member may have incomplete 5242 // array type; such a structure (and any union containing, 5243 // possibly recursively, a member that is such a structure) 5244 // shall not be a member of a structure or an element of an 5245 // array. 5246 if (FDTy->isFunctionType()) { 5247 // Field declared as a function. 5248 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5249 << FD->getDeclName(); 5250 FD->setInvalidDecl(); 5251 EnclosingDecl->setInvalidDecl(); 5252 continue; 5253 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5254 Record && Record->isStruct()) { 5255 // Flexible array member. 5256 if (NumNamedMembers < 1) { 5257 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5258 << FD->getDeclName(); 5259 FD->setInvalidDecl(); 5260 EnclosingDecl->setInvalidDecl(); 5261 continue; 5262 } 5263 // Okay, we have a legal flexible array member at the end of the struct. 5264 if (Record) 5265 Record->setHasFlexibleArrayMember(true); 5266 } else if (!FDTy->isDependentType() && 5267 RequireCompleteType(FD->getLocation(), FD->getType(), 5268 diag::err_field_incomplete)) { 5269 // Incomplete type 5270 FD->setInvalidDecl(); 5271 EnclosingDecl->setInvalidDecl(); 5272 continue; 5273 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5274 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5275 // If this is a member of a union, then entire union becomes "flexible". 5276 if (Record && Record->isUnion()) { 5277 Record->setHasFlexibleArrayMember(true); 5278 } else { 5279 // If this is a struct/class and this is not the last element, reject 5280 // it. Note that GCC supports variable sized arrays in the middle of 5281 // structures. 5282 if (i != NumFields-1) 5283 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5284 << FD->getDeclName() << FD->getType(); 5285 else { 5286 // We support flexible arrays at the end of structs in 5287 // other structs as an extension. 5288 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5289 << FD->getDeclName(); 5290 if (Record) 5291 Record->setHasFlexibleArrayMember(true); 5292 } 5293 } 5294 } 5295 if (Record && FDTTy->getDecl()->hasObjectMember()) 5296 Record->setHasObjectMember(true); 5297 } else if (FDTy->isObjCInterfaceType()) { 5298 /// A field cannot be an Objective-c object 5299 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5300 FD->setInvalidDecl(); 5301 EnclosingDecl->setInvalidDecl(); 5302 continue; 5303 } else if (getLangOptions().ObjC1 && 5304 getLangOptions().getGCMode() != LangOptions::NonGC && 5305 Record && 5306 (FD->getType()->isObjCObjectPointerType() || 5307 FD->getType().isObjCGCStrong())) 5308 Record->setHasObjectMember(true); 5309 // Keep track of the number of named members. 5310 if (FD->getIdentifier()) 5311 ++NumNamedMembers; 5312 } 5313 5314 // Okay, we successfully defined 'Record'. 5315 if (Record) { 5316 Record->completeDefinition(Context); 5317 } else { 5318 ObjCIvarDecl **ClsFields = 5319 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5320 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5321 ID->setIVarList(ClsFields, RecFields.size(), Context); 5322 ID->setLocEnd(RBrac); 5323 // Add ivar's to class's DeclContext. 5324 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5325 ClsFields[i]->setLexicalDeclContext(ID); 5326 ID->addDecl(ClsFields[i]); 5327 } 5328 // Must enforce the rule that ivars in the base classes may not be 5329 // duplicates. 5330 if (ID->getSuperClass()) { 5331 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5332 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5333 ObjCIvarDecl* Ivar = (*IVI); 5334 5335 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5336 ObjCIvarDecl* prevIvar = 5337 ID->getSuperClass()->lookupInstanceVariable(II); 5338 if (prevIvar) { 5339 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5340 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5341 } 5342 } 5343 } 5344 } 5345 } else if (ObjCImplementationDecl *IMPDecl = 5346 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5347 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5348 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5349 // Ivar declared in @implementation never belongs to the implementation. 5350 // Only it is in implementation's lexical context. 5351 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5352 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5353 } 5354 } 5355 5356 if (Attr) 5357 ProcessDeclAttributeList(S, Record, Attr); 5358} 5359 5360EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5361 EnumConstantDecl *LastEnumConst, 5362 SourceLocation IdLoc, 5363 IdentifierInfo *Id, 5364 ExprArg val) { 5365 Expr *Val = (Expr *)val.get(); 5366 5367 llvm::APSInt EnumVal(32); 5368 QualType EltTy; 5369 if (Val) { 5370 if (Val->isTypeDependent()) 5371 EltTy = Context.DependentTy; 5372 else { 5373 // Make sure to promote the operand type to int. 5374 UsualUnaryConversions(Val); 5375 if (Val != val.get()) { 5376 val.release(); 5377 val = Val; 5378 } 5379 5380 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5381 SourceLocation ExpLoc; 5382 if (!Val->isValueDependent() && 5383 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5384 Val = 0; 5385 } else { 5386 EltTy = Val->getType(); 5387 } 5388 } 5389 } 5390 5391 if (!Val) { 5392 if (LastEnumConst) { 5393 // Assign the last value + 1. 5394 EnumVal = LastEnumConst->getInitVal(); 5395 ++EnumVal; 5396 5397 // Check for overflow on increment. 5398 if (EnumVal < LastEnumConst->getInitVal()) 5399 Diag(IdLoc, diag::warn_enum_value_overflow); 5400 5401 EltTy = LastEnumConst->getType(); 5402 } else { 5403 // First value, set to zero. 5404 EltTy = Context.IntTy; 5405 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5406 } 5407 } 5408 5409 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5410 5411 val.release(); 5412 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5413 Val, EnumVal); 5414} 5415 5416 5417Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5418 DeclPtrTy lastEnumConst, 5419 SourceLocation IdLoc, 5420 IdentifierInfo *Id, 5421 SourceLocation EqualLoc, ExprTy *val) { 5422 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5423 EnumConstantDecl *LastEnumConst = 5424 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5425 Expr *Val = static_cast<Expr*>(val); 5426 5427 // The scope passed in may not be a decl scope. Zip up the scope tree until 5428 // we find one that is. 5429 S = getNonFieldDeclScope(S); 5430 5431 // Verify that there isn't already something declared with this name in this 5432 // scope. 5433 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5434 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5435 // Maybe we will complain about the shadowed template parameter. 5436 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5437 // Just pretend that we didn't see the previous declaration. 5438 PrevDecl = 0; 5439 } 5440 5441 if (PrevDecl) { 5442 // When in C++, we may get a TagDecl with the same name; in this case the 5443 // enum constant will 'hide' the tag. 5444 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5445 "Received TagDecl when not in C++!"); 5446 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5447 if (isa<EnumConstantDecl>(PrevDecl)) 5448 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5449 else 5450 Diag(IdLoc, diag::err_redefinition) << Id; 5451 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5452 if (Val) Val->Destroy(Context); 5453 return DeclPtrTy(); 5454 } 5455 } 5456 5457 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5458 IdLoc, Id, Owned(Val)); 5459 5460 // Register this decl in the current scope stack. 5461 if (New) 5462 PushOnScopeChains(New, S); 5463 5464 return DeclPtrTy::make(New); 5465} 5466 5467void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5468 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5469 DeclPtrTy *Elements, unsigned NumElements, 5470 Scope *S, AttributeList *Attr) { 5471 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5472 QualType EnumType = Context.getTypeDeclType(Enum); 5473 5474 if (Attr) 5475 ProcessDeclAttributeList(S, Enum, Attr); 5476 5477 // TODO: If the result value doesn't fit in an int, it must be a long or long 5478 // long value. ISO C does not support this, but GCC does as an extension, 5479 // emit a warning. 5480 unsigned IntWidth = Context.Target.getIntWidth(); 5481 unsigned CharWidth = Context.Target.getCharWidth(); 5482 unsigned ShortWidth = Context.Target.getShortWidth(); 5483 5484 // Verify that all the values are okay, compute the size of the values, and 5485 // reverse the list. 5486 unsigned NumNegativeBits = 0; 5487 unsigned NumPositiveBits = 0; 5488 5489 // Keep track of whether all elements have type int. 5490 bool AllElementsInt = true; 5491 5492 for (unsigned i = 0; i != NumElements; ++i) { 5493 EnumConstantDecl *ECD = 5494 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5495 if (!ECD) continue; // Already issued a diagnostic. 5496 5497 // If the enum value doesn't fit in an int, emit an extension warning. 5498 const llvm::APSInt &InitVal = ECD->getInitVal(); 5499 assert(InitVal.getBitWidth() >= IntWidth && 5500 "Should have promoted value to int"); 5501 if (InitVal.getBitWidth() > IntWidth) { 5502 llvm::APSInt V(InitVal); 5503 V.trunc(IntWidth); 5504 V.extend(InitVal.getBitWidth()); 5505 if (V != InitVal) 5506 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5507 << InitVal.toString(10); 5508 } 5509 5510 // Keep track of the size of positive and negative values. 5511 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5512 NumPositiveBits = std::max(NumPositiveBits, 5513 (unsigned)InitVal.getActiveBits()); 5514 else 5515 NumNegativeBits = std::max(NumNegativeBits, 5516 (unsigned)InitVal.getMinSignedBits()); 5517 5518 // Keep track of whether every enum element has type int (very commmon). 5519 if (AllElementsInt) 5520 AllElementsInt = ECD->getType() == Context.IntTy; 5521 } 5522 5523 // Figure out the type that should be used for this enum. 5524 // FIXME: Support -fshort-enums. 5525 QualType BestType; 5526 unsigned BestWidth; 5527 5528 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5529 5530 if (NumNegativeBits) { 5531 // If there is a negative value, figure out the smallest integer type (of 5532 // int/long/longlong) that fits. 5533 // If it's packed, check also if it fits a char or a short. 5534 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5535 BestType = Context.SignedCharTy; 5536 BestWidth = CharWidth; 5537 } else if (Packed && NumNegativeBits <= ShortWidth && 5538 NumPositiveBits < ShortWidth) { 5539 BestType = Context.ShortTy; 5540 BestWidth = ShortWidth; 5541 } 5542 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5543 BestType = Context.IntTy; 5544 BestWidth = IntWidth; 5545 } else { 5546 BestWidth = Context.Target.getLongWidth(); 5547 5548 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5549 BestType = Context.LongTy; 5550 else { 5551 BestWidth = Context.Target.getLongLongWidth(); 5552 5553 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5554 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5555 BestType = Context.LongLongTy; 5556 } 5557 } 5558 } else { 5559 // If there is no negative value, figure out which of uint, ulong, ulonglong 5560 // fits. 5561 // If it's packed, check also if it fits a char or a short. 5562 if (Packed && NumPositiveBits <= CharWidth) { 5563 BestType = Context.UnsignedCharTy; 5564 BestWidth = CharWidth; 5565 } else if (Packed && NumPositiveBits <= ShortWidth) { 5566 BestType = Context.UnsignedShortTy; 5567 BestWidth = ShortWidth; 5568 } 5569 else if (NumPositiveBits <= IntWidth) { 5570 BestType = Context.UnsignedIntTy; 5571 BestWidth = IntWidth; 5572 } else if (NumPositiveBits <= 5573 (BestWidth = Context.Target.getLongWidth())) { 5574 BestType = Context.UnsignedLongTy; 5575 } else { 5576 BestWidth = Context.Target.getLongLongWidth(); 5577 assert(NumPositiveBits <= BestWidth && 5578 "How could an initializer get larger than ULL?"); 5579 BestType = Context.UnsignedLongLongTy; 5580 } 5581 } 5582 5583 // Loop over all of the enumerator constants, changing their types to match 5584 // the type of the enum if needed. 5585 for (unsigned i = 0; i != NumElements; ++i) { 5586 EnumConstantDecl *ECD = 5587 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5588 if (!ECD) continue; // Already issued a diagnostic. 5589 5590 // Standard C says the enumerators have int type, but we allow, as an 5591 // extension, the enumerators to be larger than int size. If each 5592 // enumerator value fits in an int, type it as an int, otherwise type it the 5593 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5594 // that X has type 'int', not 'unsigned'. 5595 if (ECD->getType() == Context.IntTy) { 5596 // Make sure the init value is signed. 5597 llvm::APSInt IV = ECD->getInitVal(); 5598 IV.setIsSigned(true); 5599 ECD->setInitVal(IV); 5600 5601 if (getLangOptions().CPlusPlus) 5602 // C++ [dcl.enum]p4: Following the closing brace of an 5603 // enum-specifier, each enumerator has the type of its 5604 // enumeration. 5605 ECD->setType(EnumType); 5606 continue; // Already int type. 5607 } 5608 5609 // Determine whether the value fits into an int. 5610 llvm::APSInt InitVal = ECD->getInitVal(); 5611 bool FitsInInt; 5612 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5613 FitsInInt = InitVal.getActiveBits() < IntWidth; 5614 else 5615 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5616 5617 // If it fits into an integer type, force it. Otherwise force it to match 5618 // the enum decl type. 5619 QualType NewTy; 5620 unsigned NewWidth; 5621 bool NewSign; 5622 if (FitsInInt) { 5623 NewTy = Context.IntTy; 5624 NewWidth = IntWidth; 5625 NewSign = true; 5626 } else if (ECD->getType() == BestType) { 5627 // Already the right type! 5628 if (getLangOptions().CPlusPlus) 5629 // C++ [dcl.enum]p4: Following the closing brace of an 5630 // enum-specifier, each enumerator has the type of its 5631 // enumeration. 5632 ECD->setType(EnumType); 5633 continue; 5634 } else { 5635 NewTy = BestType; 5636 NewWidth = BestWidth; 5637 NewSign = BestType->isSignedIntegerType(); 5638 } 5639 5640 // Adjust the APSInt value. 5641 InitVal.extOrTrunc(NewWidth); 5642 InitVal.setIsSigned(NewSign); 5643 ECD->setInitVal(InitVal); 5644 5645 // Adjust the Expr initializer and type. 5646 if (ECD->getInitExpr()) 5647 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5648 CastExpr::CK_IntegralCast, 5649 ECD->getInitExpr(), 5650 /*isLvalue=*/false)); 5651 if (getLangOptions().CPlusPlus) 5652 // C++ [dcl.enum]p4: Following the closing brace of an 5653 // enum-specifier, each enumerator has the type of its 5654 // enumeration. 5655 ECD->setType(EnumType); 5656 else 5657 ECD->setType(NewTy); 5658 } 5659 5660 Enum->completeDefinition(Context, BestType); 5661} 5662 5663Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5664 ExprArg expr) { 5665 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5666 5667 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5668 Loc, AsmString); 5669 CurContext->addDecl(New); 5670 return DeclPtrTy::make(New); 5671} 5672 5673void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5674 SourceLocation PragmaLoc, 5675 SourceLocation NameLoc) { 5676 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5677 5678 if (PrevDecl) { 5679 PrevDecl->addAttr(::new (Context) WeakAttr()); 5680 } else { 5681 (void)WeakUndeclaredIdentifiers.insert( 5682 std::pair<IdentifierInfo*,WeakInfo> 5683 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5684 } 5685} 5686 5687void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5688 IdentifierInfo* AliasName, 5689 SourceLocation PragmaLoc, 5690 SourceLocation NameLoc, 5691 SourceLocation AliasNameLoc) { 5692 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5693 WeakInfo W = WeakInfo(Name, NameLoc); 5694 5695 if (PrevDecl) { 5696 if (!PrevDecl->hasAttr<AliasAttr>()) 5697 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5698 DeclApplyPragmaWeak(TUScope, ND, W); 5699 } else { 5700 (void)WeakUndeclaredIdentifiers.insert( 5701 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5702 } 5703} 5704