SemaDecl.cpp revision 6e8247556807ecaaac470852222762db998a05b2
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 387void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 388 if (S->decl_empty()) return; 389 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 390 "Scope shouldn't contain decls!"); 391 392 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 393 I != E; ++I) { 394 Decl *TmpD = (*I).getAs<Decl>(); 395 assert(TmpD && "This decl didn't get pushed??"); 396 397 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 398 NamedDecl *D = cast<NamedDecl>(TmpD); 399 400 if (!D->getDeclName()) continue; 401 402 // Diagnose unused variables in this scope. 403 if (!D->isUsed() && !D->hasAttr<UnusedAttr>() && isa<VarDecl>(D) && 404 !isa<ParmVarDecl>(D) && !isa<ImplicitParamDecl>(D) && 405 D->getDeclContext()->isFunctionOrMethod()) 406 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 407 408 // Remove this name from our lexical scope. 409 IdResolver.RemoveDecl(D); 410 } 411} 412 413/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 414/// return 0 if one not found. 415ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 416 // The third "scope" argument is 0 since we aren't enabling lazy built-in 417 // creation from this context. 418 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 419 420 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 421} 422 423/// getNonFieldDeclScope - Retrieves the innermost scope, starting 424/// from S, where a non-field would be declared. This routine copes 425/// with the difference between C and C++ scoping rules in structs and 426/// unions. For example, the following code is well-formed in C but 427/// ill-formed in C++: 428/// @code 429/// struct S6 { 430/// enum { BAR } e; 431/// }; 432/// 433/// void test_S6() { 434/// struct S6 a; 435/// a.e = BAR; 436/// } 437/// @endcode 438/// For the declaration of BAR, this routine will return a different 439/// scope. The scope S will be the scope of the unnamed enumeration 440/// within S6. In C++, this routine will return the scope associated 441/// with S6, because the enumeration's scope is a transparent 442/// context but structures can contain non-field names. In C, this 443/// routine will return the translation unit scope, since the 444/// enumeration's scope is a transparent context and structures cannot 445/// contain non-field names. 446Scope *Sema::getNonFieldDeclScope(Scope *S) { 447 while (((S->getFlags() & Scope::DeclScope) == 0) || 448 (S->getEntity() && 449 ((DeclContext *)S->getEntity())->isTransparentContext()) || 450 (S->isClassScope() && !getLangOptions().CPlusPlus)) 451 S = S->getParent(); 452 return S; 453} 454 455void Sema::InitBuiltinVaListType() { 456 if (!Context.getBuiltinVaListType().isNull()) 457 return; 458 459 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 460 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 461 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 462 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 463} 464 465/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 466/// file scope. lazily create a decl for it. ForRedeclaration is true 467/// if we're creating this built-in in anticipation of redeclaring the 468/// built-in. 469NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 470 Scope *S, bool ForRedeclaration, 471 SourceLocation Loc) { 472 Builtin::ID BID = (Builtin::ID)bid; 473 474 if (Context.BuiltinInfo.hasVAListUse(BID)) 475 InitBuiltinVaListType(); 476 477 ASTContext::GetBuiltinTypeError Error; 478 QualType R = Context.GetBuiltinType(BID, Error); 479 switch (Error) { 480 case ASTContext::GE_None: 481 // Okay 482 break; 483 484 case ASTContext::GE_Missing_stdio: 485 if (ForRedeclaration) 486 Diag(Loc, diag::err_implicit_decl_requires_stdio) 487 << Context.BuiltinInfo.GetName(BID); 488 return 0; 489 490 case ASTContext::GE_Missing_setjmp: 491 if (ForRedeclaration) 492 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 493 << Context.BuiltinInfo.GetName(BID); 494 return 0; 495 } 496 497 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 498 Diag(Loc, diag::ext_implicit_lib_function_decl) 499 << Context.BuiltinInfo.GetName(BID) 500 << R; 501 if (Context.BuiltinInfo.getHeaderName(BID) && 502 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 503 != Diagnostic::Ignored) 504 Diag(Loc, diag::note_please_include_header) 505 << Context.BuiltinInfo.getHeaderName(BID) 506 << Context.BuiltinInfo.GetName(BID); 507 } 508 509 FunctionDecl *New = FunctionDecl::Create(Context, 510 Context.getTranslationUnitDecl(), 511 Loc, II, R, /*DInfo=*/0, 512 FunctionDecl::Extern, false, 513 /*hasPrototype=*/true); 514 New->setImplicit(); 515 516 // Create Decl objects for each parameter, adding them to the 517 // FunctionDecl. 518 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 519 llvm::SmallVector<ParmVarDecl*, 16> Params; 520 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 521 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 522 FT->getArgType(i), /*DInfo=*/0, 523 VarDecl::None, 0)); 524 New->setParams(Context, Params.data(), Params.size()); 525 } 526 527 AddKnownFunctionAttributes(New); 528 529 // TUScope is the translation-unit scope to insert this function into. 530 // FIXME: This is hideous. We need to teach PushOnScopeChains to 531 // relate Scopes to DeclContexts, and probably eliminate CurContext 532 // entirely, but we're not there yet. 533 DeclContext *SavedContext = CurContext; 534 CurContext = Context.getTranslationUnitDecl(); 535 PushOnScopeChains(New, TUScope); 536 CurContext = SavedContext; 537 return New; 538} 539 540/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 541/// same name and scope as a previous declaration 'Old'. Figure out 542/// how to resolve this situation, merging decls or emitting 543/// diagnostics as appropriate. If there was an error, set New to be invalid. 544/// 545void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 546 // If either decl is known invalid already, set the new one to be invalid and 547 // don't bother doing any merging checks. 548 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 549 return New->setInvalidDecl(); 550 551 // Allow multiple definitions for ObjC built-in typedefs. 552 // FIXME: Verify the underlying types are equivalent! 553 if (getLangOptions().ObjC1) { 554 const IdentifierInfo *TypeID = New->getIdentifier(); 555 switch (TypeID->getLength()) { 556 default: break; 557 case 2: 558 if (!TypeID->isStr("id")) 559 break; 560 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 561 // Install the built-in type for 'id', ignoring the current definition. 562 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 563 return; 564 case 5: 565 if (!TypeID->isStr("Class")) 566 break; 567 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 568 // Install the built-in type for 'Class', ignoring the current definition. 569 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 570 return; 571 case 3: 572 if (!TypeID->isStr("SEL")) 573 break; 574 Context.setObjCSelType(Context.getTypeDeclType(New)); 575 return; 576 case 8: 577 if (!TypeID->isStr("Protocol")) 578 break; 579 Context.setObjCProtoType(New->getUnderlyingType()); 580 return; 581 } 582 // Fall through - the typedef name was not a builtin type. 583 } 584 // Verify the old decl was also a type. 585 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 586 if (!Old) { 587 Diag(New->getLocation(), diag::err_redefinition_different_kind) 588 << New->getDeclName(); 589 if (OldD->getLocation().isValid()) 590 Diag(OldD->getLocation(), diag::note_previous_definition); 591 return New->setInvalidDecl(); 592 } 593 594 // Determine the "old" type we'll use for checking and diagnostics. 595 QualType OldType; 596 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 597 OldType = OldTypedef->getUnderlyingType(); 598 else 599 OldType = Context.getTypeDeclType(Old); 600 601 // If the typedef types are not identical, reject them in all languages and 602 // with any extensions enabled. 603 604 if (OldType != New->getUnderlyingType() && 605 Context.getCanonicalType(OldType) != 606 Context.getCanonicalType(New->getUnderlyingType())) { 607 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 608 << New->getUnderlyingType() << OldType; 609 if (Old->getLocation().isValid()) 610 Diag(Old->getLocation(), diag::note_previous_definition); 611 return New->setInvalidDecl(); 612 } 613 614 if (getLangOptions().Microsoft) 615 return; 616 617 // C++ [dcl.typedef]p2: 618 // In a given non-class scope, a typedef specifier can be used to 619 // redefine the name of any type declared in that scope to refer 620 // to the type to which it already refers. 621 if (getLangOptions().CPlusPlus) { 622 if (!isa<CXXRecordDecl>(CurContext)) 623 return; 624 Diag(New->getLocation(), diag::err_redefinition) 625 << New->getDeclName(); 626 Diag(Old->getLocation(), diag::note_previous_definition); 627 return New->setInvalidDecl(); 628 } 629 630 // If we have a redefinition of a typedef in C, emit a warning. This warning 631 // is normally mapped to an error, but can be controlled with 632 // -Wtypedef-redefinition. If either the original or the redefinition is 633 // in a system header, don't emit this for compatibility with GCC. 634 if (PP.getDiagnostics().getSuppressSystemWarnings() && 635 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 636 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 637 return; 638 639 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 640 << New->getDeclName(); 641 Diag(Old->getLocation(), diag::note_previous_definition); 642 return; 643} 644 645/// DeclhasAttr - returns true if decl Declaration already has the target 646/// attribute. 647static bool 648DeclHasAttr(const Decl *decl, const Attr *target) { 649 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 650 if (attr->getKind() == target->getKind()) 651 return true; 652 653 return false; 654} 655 656/// MergeAttributes - append attributes from the Old decl to the New one. 657static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 658 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 659 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 660 Attr *NewAttr = attr->clone(C); 661 NewAttr->setInherited(true); 662 New->addAttr(NewAttr); 663 } 664 } 665} 666 667/// Used in MergeFunctionDecl to keep track of function parameters in 668/// C. 669struct GNUCompatibleParamWarning { 670 ParmVarDecl *OldParm; 671 ParmVarDecl *NewParm; 672 QualType PromotedType; 673}; 674 675/// MergeFunctionDecl - We just parsed a function 'New' from 676/// declarator D which has the same name and scope as a previous 677/// declaration 'Old'. Figure out how to resolve this situation, 678/// merging decls or emitting diagnostics as appropriate. 679/// 680/// In C++, New and Old must be declarations that are not 681/// overloaded. Use IsOverload to determine whether New and Old are 682/// overloaded, and to select the Old declaration that New should be 683/// merged with. 684/// 685/// Returns true if there was an error, false otherwise. 686bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 687 assert(!isa<OverloadedFunctionDecl>(OldD) && 688 "Cannot merge with an overloaded function declaration"); 689 690 // Verify the old decl was also a function. 691 FunctionDecl *Old = 0; 692 if (FunctionTemplateDecl *OldFunctionTemplate 693 = dyn_cast<FunctionTemplateDecl>(OldD)) 694 Old = OldFunctionTemplate->getTemplatedDecl(); 695 else 696 Old = dyn_cast<FunctionDecl>(OldD); 697 if (!Old) { 698 Diag(New->getLocation(), diag::err_redefinition_different_kind) 699 << New->getDeclName(); 700 Diag(OldD->getLocation(), diag::note_previous_definition); 701 return true; 702 } 703 704 // Determine whether the previous declaration was a definition, 705 // implicit declaration, or a declaration. 706 diag::kind PrevDiag; 707 if (Old->isThisDeclarationADefinition()) 708 PrevDiag = diag::note_previous_definition; 709 else if (Old->isImplicit()) 710 PrevDiag = diag::note_previous_implicit_declaration; 711 else 712 PrevDiag = diag::note_previous_declaration; 713 714 QualType OldQType = Context.getCanonicalType(Old->getType()); 715 QualType NewQType = Context.getCanonicalType(New->getType()); 716 717 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 718 New->getStorageClass() == FunctionDecl::Static && 719 Old->getStorageClass() != FunctionDecl::Static) { 720 Diag(New->getLocation(), diag::err_static_non_static) 721 << New; 722 Diag(Old->getLocation(), PrevDiag); 723 return true; 724 } 725 726 if (getLangOptions().CPlusPlus) { 727 // (C++98 13.1p2): 728 // Certain function declarations cannot be overloaded: 729 // -- Function declarations that differ only in the return type 730 // cannot be overloaded. 731 QualType OldReturnType 732 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 733 QualType NewReturnType 734 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 735 if (OldReturnType != NewReturnType) { 736 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 737 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 738 return true; 739 } 740 741 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 742 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 743 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 744 NewMethod->getLexicalDeclContext()->isRecord()) { 745 // -- Member function declarations with the same name and the 746 // same parameter types cannot be overloaded if any of them 747 // is a static member function declaration. 748 if (OldMethod->isStatic() || NewMethod->isStatic()) { 749 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 750 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 751 return true; 752 } 753 754 // C++ [class.mem]p1: 755 // [...] A member shall not be declared twice in the 756 // member-specification, except that a nested class or member 757 // class template can be declared and then later defined. 758 unsigned NewDiag; 759 if (isa<CXXConstructorDecl>(OldMethod)) 760 NewDiag = diag::err_constructor_redeclared; 761 else if (isa<CXXDestructorDecl>(NewMethod)) 762 NewDiag = diag::err_destructor_redeclared; 763 else if (isa<CXXConversionDecl>(NewMethod)) 764 NewDiag = diag::err_conv_function_redeclared; 765 else 766 NewDiag = diag::err_member_redeclared; 767 768 Diag(New->getLocation(), NewDiag); 769 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 770 } 771 772 // (C++98 8.3.5p3): 773 // All declarations for a function shall agree exactly in both the 774 // return type and the parameter-type-list. 775 if (OldQType == NewQType) 776 return MergeCompatibleFunctionDecls(New, Old); 777 778 // Fall through for conflicting redeclarations and redefinitions. 779 } 780 781 // C: Function types need to be compatible, not identical. This handles 782 // duplicate function decls like "void f(int); void f(enum X);" properly. 783 if (!getLangOptions().CPlusPlus && 784 Context.typesAreCompatible(OldQType, NewQType)) { 785 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 786 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 787 const FunctionProtoType *OldProto = 0; 788 if (isa<FunctionNoProtoType>(NewFuncType) && 789 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 790 // The old declaration provided a function prototype, but the 791 // new declaration does not. Merge in the prototype. 792 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 793 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 794 OldProto->arg_type_end()); 795 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 796 ParamTypes.data(), ParamTypes.size(), 797 OldProto->isVariadic(), 798 OldProto->getTypeQuals()); 799 New->setType(NewQType); 800 New->setHasInheritedPrototype(); 801 802 // Synthesize a parameter for each argument type. 803 llvm::SmallVector<ParmVarDecl*, 16> Params; 804 for (FunctionProtoType::arg_type_iterator 805 ParamType = OldProto->arg_type_begin(), 806 ParamEnd = OldProto->arg_type_end(); 807 ParamType != ParamEnd; ++ParamType) { 808 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 809 SourceLocation(), 0, 810 *ParamType, /*DInfo=*/0, 811 VarDecl::None, 0); 812 Param->setImplicit(); 813 Params.push_back(Param); 814 } 815 816 New->setParams(Context, Params.data(), Params.size()); 817 } 818 819 return MergeCompatibleFunctionDecls(New, Old); 820 } 821 822 // GNU C permits a K&R definition to follow a prototype declaration 823 // if the declared types of the parameters in the K&R definition 824 // match the types in the prototype declaration, even when the 825 // promoted types of the parameters from the K&R definition differ 826 // from the types in the prototype. GCC then keeps the types from 827 // the prototype. 828 // 829 // If a variadic prototype is followed by a non-variadic K&R definition, 830 // the K&R definition becomes variadic. This is sort of an edge case, but 831 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 832 // C99 6.9.1p8. 833 if (!getLangOptions().CPlusPlus && 834 Old->hasPrototype() && !New->hasPrototype() && 835 New->getType()->getAs<FunctionProtoType>() && 836 Old->getNumParams() == New->getNumParams()) { 837 llvm::SmallVector<QualType, 16> ArgTypes; 838 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 839 const FunctionProtoType *OldProto 840 = Old->getType()->getAs<FunctionProtoType>(); 841 const FunctionProtoType *NewProto 842 = New->getType()->getAs<FunctionProtoType>(); 843 844 // Determine whether this is the GNU C extension. 845 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 846 NewProto->getResultType()); 847 bool LooseCompatible = !MergedReturn.isNull(); 848 for (unsigned Idx = 0, End = Old->getNumParams(); 849 LooseCompatible && Idx != End; ++Idx) { 850 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 851 ParmVarDecl *NewParm = New->getParamDecl(Idx); 852 if (Context.typesAreCompatible(OldParm->getType(), 853 NewProto->getArgType(Idx))) { 854 ArgTypes.push_back(NewParm->getType()); 855 } else if (Context.typesAreCompatible(OldParm->getType(), 856 NewParm->getType())) { 857 GNUCompatibleParamWarning Warn 858 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 859 Warnings.push_back(Warn); 860 ArgTypes.push_back(NewParm->getType()); 861 } else 862 LooseCompatible = false; 863 } 864 865 if (LooseCompatible) { 866 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 867 Diag(Warnings[Warn].NewParm->getLocation(), 868 diag::ext_param_promoted_not_compatible_with_prototype) 869 << Warnings[Warn].PromotedType 870 << Warnings[Warn].OldParm->getType(); 871 Diag(Warnings[Warn].OldParm->getLocation(), 872 diag::note_previous_declaration); 873 } 874 875 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 876 ArgTypes.size(), 877 OldProto->isVariadic(), 0)); 878 return MergeCompatibleFunctionDecls(New, Old); 879 } 880 881 // Fall through to diagnose conflicting types. 882 } 883 884 // A function that has already been declared has been redeclared or defined 885 // with a different type- show appropriate diagnostic 886 if (unsigned BuiltinID = Old->getBuiltinID()) { 887 // The user has declared a builtin function with an incompatible 888 // signature. 889 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 890 // The function the user is redeclaring is a library-defined 891 // function like 'malloc' or 'printf'. Warn about the 892 // redeclaration, then pretend that we don't know about this 893 // library built-in. 894 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 895 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 896 << Old << Old->getType(); 897 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 898 Old->setInvalidDecl(); 899 return false; 900 } 901 902 PrevDiag = diag::note_previous_builtin_declaration; 903 } 904 905 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 906 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 907 return true; 908} 909 910/// \brief Completes the merge of two function declarations that are 911/// known to be compatible. 912/// 913/// This routine handles the merging of attributes and other 914/// properties of function declarations form the old declaration to 915/// the new declaration, once we know that New is in fact a 916/// redeclaration of Old. 917/// 918/// \returns false 919bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 920 // Merge the attributes 921 MergeAttributes(New, Old, Context); 922 923 // Merge the storage class. 924 if (Old->getStorageClass() != FunctionDecl::Extern && 925 Old->getStorageClass() != FunctionDecl::None) 926 New->setStorageClass(Old->getStorageClass()); 927 928 // Merge "pure" flag. 929 if (Old->isPure()) 930 New->setPure(); 931 932 // Merge the "deleted" flag. 933 if (Old->isDeleted()) 934 New->setDeleted(); 935 936 if (getLangOptions().CPlusPlus) 937 return MergeCXXFunctionDecl(New, Old); 938 939 return false; 940} 941 942/// MergeVarDecl - We just parsed a variable 'New' which has the same name 943/// and scope as a previous declaration 'Old'. Figure out how to resolve this 944/// situation, merging decls or emitting diagnostics as appropriate. 945/// 946/// Tentative definition rules (C99 6.9.2p2) are checked by 947/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 948/// definitions here, since the initializer hasn't been attached. 949/// 950void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 951 // If either decl is invalid, make sure the new one is marked invalid and 952 // don't do any other checking. 953 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 954 return New->setInvalidDecl(); 955 956 // Verify the old decl was also a variable. 957 VarDecl *Old = dyn_cast<VarDecl>(OldD); 958 if (!Old) { 959 Diag(New->getLocation(), diag::err_redefinition_different_kind) 960 << New->getDeclName(); 961 Diag(OldD->getLocation(), diag::note_previous_definition); 962 return New->setInvalidDecl(); 963 } 964 965 MergeAttributes(New, Old, Context); 966 967 // Merge the types 968 QualType MergedT; 969 if (getLangOptions().CPlusPlus) { 970 if (Context.hasSameType(New->getType(), Old->getType())) 971 MergedT = New->getType(); 972 // C++ [basic.types]p7: 973 // [...] The declared type of an array object might be an array of 974 // unknown size and therefore be incomplete at one point in a 975 // translation unit and complete later on; [...] 976 else if (Old->getType()->isIncompleteArrayType() && 977 New->getType()->isArrayType()) { 978 CanQual<ArrayType> OldArray 979 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 980 CanQual<ArrayType> NewArray 981 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 982 if (OldArray->getElementType() == NewArray->getElementType()) 983 MergedT = New->getType(); 984 } 985 } else { 986 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 987 } 988 if (MergedT.isNull()) { 989 Diag(New->getLocation(), diag::err_redefinition_different_type) 990 << New->getDeclName(); 991 Diag(Old->getLocation(), diag::note_previous_definition); 992 return New->setInvalidDecl(); 993 } 994 New->setType(MergedT); 995 996 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 997 if (New->getStorageClass() == VarDecl::Static && 998 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 999 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1000 Diag(Old->getLocation(), diag::note_previous_definition); 1001 return New->setInvalidDecl(); 1002 } 1003 // C99 6.2.2p4: 1004 // For an identifier declared with the storage-class specifier 1005 // extern in a scope in which a prior declaration of that 1006 // identifier is visible,23) if the prior declaration specifies 1007 // internal or external linkage, the linkage of the identifier at 1008 // the later declaration is the same as the linkage specified at 1009 // the prior declaration. If no prior declaration is visible, or 1010 // if the prior declaration specifies no linkage, then the 1011 // identifier has external linkage. 1012 if (New->hasExternalStorage() && Old->hasLinkage()) 1013 /* Okay */; 1014 else if (New->getStorageClass() != VarDecl::Static && 1015 Old->getStorageClass() == VarDecl::Static) { 1016 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1017 Diag(Old->getLocation(), diag::note_previous_definition); 1018 return New->setInvalidDecl(); 1019 } 1020 1021 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1022 1023 // FIXME: The test for external storage here seems wrong? We still 1024 // need to check for mismatches. 1025 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1026 // Don't complain about out-of-line definitions of static members. 1027 !(Old->getLexicalDeclContext()->isRecord() && 1028 !New->getLexicalDeclContext()->isRecord())) { 1029 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1030 Diag(Old->getLocation(), diag::note_previous_definition); 1031 return New->setInvalidDecl(); 1032 } 1033 1034 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1035 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1036 Diag(Old->getLocation(), diag::note_previous_definition); 1037 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1038 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1039 Diag(Old->getLocation(), diag::note_previous_definition); 1040 } 1041 1042 // Keep a chain of previous declarations. 1043 New->setPreviousDeclaration(Old); 1044} 1045 1046/// CheckFallThrough - Check that we don't fall off the end of a 1047/// Statement that should return a value. 1048/// 1049/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1050/// MaybeFallThrough iff we might or might not fall off the end, 1051/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1052/// return. We assume NeverFallThrough iff we never fall off the end of the 1053/// statement but we may return. We assume that functions not marked noreturn 1054/// will return. 1055Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1056 // FIXME: Eventually share this CFG object when we have other warnings based 1057 // of the CFG. This can be done using AnalysisContext. 1058 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1059 1060 // FIXME: They should never return 0, fix that, delete this code. 1061 if (cfg == 0) 1062 // FIXME: This should be NeverFallThrough 1063 return NeverFallThroughOrReturn; 1064 // The CFG leaves in dead things, and we don't want to dead code paths to 1065 // confuse us, so we mark all live things first. 1066 std::queue<CFGBlock*> workq; 1067 llvm::BitVector live(cfg->getNumBlockIDs()); 1068 // Prep work queue 1069 workq.push(&cfg->getEntry()); 1070 // Solve 1071 while (!workq.empty()) { 1072 CFGBlock *item = workq.front(); 1073 workq.pop(); 1074 live.set(item->getBlockID()); 1075 for (CFGBlock::succ_iterator I=item->succ_begin(), 1076 E=item->succ_end(); 1077 I != E; 1078 ++I) { 1079 if ((*I) && !live[(*I)->getBlockID()]) { 1080 live.set((*I)->getBlockID()); 1081 workq.push(*I); 1082 } 1083 } 1084 } 1085 1086 // Now we know what is live, we check the live precessors of the exit block 1087 // and look for fall through paths, being careful to ignore normal returns, 1088 // and exceptional paths. 1089 bool HasLiveReturn = false; 1090 bool HasFakeEdge = false; 1091 bool HasPlainEdge = false; 1092 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1093 E = cfg->getExit().pred_end(); 1094 I != E; 1095 ++I) { 1096 CFGBlock& B = **I; 1097 if (!live[B.getBlockID()]) 1098 continue; 1099 if (B.size() == 0) { 1100 // A labeled empty statement, or the entry block... 1101 HasPlainEdge = true; 1102 continue; 1103 } 1104 Stmt *S = B[B.size()-1]; 1105 if (isa<ReturnStmt>(S)) { 1106 HasLiveReturn = true; 1107 continue; 1108 } 1109 if (isa<ObjCAtThrowStmt>(S)) { 1110 HasFakeEdge = true; 1111 continue; 1112 } 1113 if (isa<CXXThrowExpr>(S)) { 1114 HasFakeEdge = true; 1115 continue; 1116 } 1117 bool NoReturnEdge = false; 1118 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1119 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1120 if (CEE->getType().getNoReturnAttr()) { 1121 NoReturnEdge = true; 1122 HasFakeEdge = true; 1123 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1124 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1125 if (FD->hasAttr<NoReturnAttr>()) { 1126 NoReturnEdge = true; 1127 HasFakeEdge = true; 1128 } 1129 } 1130 } 1131 } 1132 // FIXME: Add noreturn message sends. 1133 if (NoReturnEdge == false) 1134 HasPlainEdge = true; 1135 } 1136 if (!HasPlainEdge) { 1137 if (HasLiveReturn) 1138 return NeverFallThrough; 1139 return NeverFallThroughOrReturn; 1140 } 1141 if (HasFakeEdge || HasLiveReturn) 1142 return MaybeFallThrough; 1143 // This says AlwaysFallThrough for calls to functions that are not marked 1144 // noreturn, that don't return. If people would like this warning to be more 1145 // accurate, such functions should be marked as noreturn. 1146 return AlwaysFallThrough; 1147} 1148 1149/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1150/// function that should return a value. Check that we don't fall off the end 1151/// of a noreturn function. We assume that functions and blocks not marked 1152/// noreturn will return. 1153void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1154 // FIXME: Would be nice if we had a better way to control cascading errors, 1155 // but for now, avoid them. The problem is that when Parse sees: 1156 // int foo() { return a; } 1157 // The return is eaten and the Sema code sees just: 1158 // int foo() { } 1159 // which this code would then warn about. 1160 if (getDiagnostics().hasErrorOccurred()) 1161 return; 1162 1163 bool ReturnsVoid = false; 1164 bool HasNoReturn = false; 1165 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1166 // If the result type of the function is a dependent type, we don't know 1167 // whether it will be void or not, so don't 1168 if (FD->getResultType()->isDependentType()) 1169 return; 1170 if (FD->getResultType()->isVoidType()) 1171 ReturnsVoid = true; 1172 if (FD->hasAttr<NoReturnAttr>()) 1173 HasNoReturn = true; 1174 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1175 if (MD->getResultType()->isVoidType()) 1176 ReturnsVoid = true; 1177 if (MD->hasAttr<NoReturnAttr>()) 1178 HasNoReturn = true; 1179 } 1180 1181 // Short circuit for compilation speed. 1182 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1183 == Diagnostic::Ignored || ReturnsVoid) 1184 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1185 == Diagnostic::Ignored || !HasNoReturn) 1186 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1187 == Diagnostic::Ignored || !ReturnsVoid)) 1188 return; 1189 // FIXME: Function try block 1190 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1191 switch (CheckFallThrough(Body)) { 1192 case MaybeFallThrough: 1193 if (HasNoReturn) 1194 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1195 else if (!ReturnsVoid) 1196 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1197 break; 1198 case AlwaysFallThrough: 1199 if (HasNoReturn) 1200 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1201 else if (!ReturnsVoid) 1202 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1203 break; 1204 case NeverFallThroughOrReturn: 1205 if (ReturnsVoid && !HasNoReturn) 1206 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1207 break; 1208 case NeverFallThrough: 1209 break; 1210 } 1211 } 1212} 1213 1214/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1215/// that should return a value. Check that we don't fall off the end of a 1216/// noreturn block. We assume that functions and blocks not marked noreturn 1217/// will return. 1218void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1219 // FIXME: Would be nice if we had a better way to control cascading errors, 1220 // but for now, avoid them. The problem is that when Parse sees: 1221 // int foo() { return a; } 1222 // The return is eaten and the Sema code sees just: 1223 // int foo() { } 1224 // which this code would then warn about. 1225 if (getDiagnostics().hasErrorOccurred()) 1226 return; 1227 bool ReturnsVoid = false; 1228 bool HasNoReturn = false; 1229 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1230 if (FT->getResultType()->isVoidType()) 1231 ReturnsVoid = true; 1232 if (FT->getNoReturnAttr()) 1233 HasNoReturn = true; 1234 } 1235 1236 // Short circuit for compilation speed. 1237 if (ReturnsVoid 1238 && !HasNoReturn 1239 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1240 == Diagnostic::Ignored || !ReturnsVoid)) 1241 return; 1242 // FIXME: Funtion try block 1243 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1244 switch (CheckFallThrough(Body)) { 1245 case MaybeFallThrough: 1246 if (HasNoReturn) 1247 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1248 else if (!ReturnsVoid) 1249 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1250 break; 1251 case AlwaysFallThrough: 1252 if (HasNoReturn) 1253 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1254 else if (!ReturnsVoid) 1255 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1256 break; 1257 case NeverFallThroughOrReturn: 1258 if (ReturnsVoid) 1259 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1260 break; 1261 case NeverFallThrough: 1262 break; 1263 } 1264 } 1265} 1266 1267/// CheckParmsForFunctionDef - Check that the parameters of the given 1268/// function are appropriate for the definition of a function. This 1269/// takes care of any checks that cannot be performed on the 1270/// declaration itself, e.g., that the types of each of the function 1271/// parameters are complete. 1272bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1273 bool HasInvalidParm = false; 1274 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1275 ParmVarDecl *Param = FD->getParamDecl(p); 1276 1277 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1278 // function declarator that is part of a function definition of 1279 // that function shall not have incomplete type. 1280 // 1281 // This is also C++ [dcl.fct]p6. 1282 if (!Param->isInvalidDecl() && 1283 RequireCompleteType(Param->getLocation(), Param->getType(), 1284 diag::err_typecheck_decl_incomplete_type)) { 1285 Param->setInvalidDecl(); 1286 HasInvalidParm = true; 1287 } 1288 1289 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1290 // declaration of each parameter shall include an identifier. 1291 if (Param->getIdentifier() == 0 && 1292 !Param->isImplicit() && 1293 !getLangOptions().CPlusPlus) 1294 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1295 } 1296 1297 return HasInvalidParm; 1298} 1299 1300/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1301/// no declarator (e.g. "struct foo;") is parsed. 1302Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1303 // FIXME: Error on auto/register at file scope 1304 // FIXME: Error on inline/virtual/explicit 1305 // FIXME: Error on invalid restrict 1306 // FIXME: Warn on useless __thread 1307 // FIXME: Warn on useless const/volatile 1308 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1309 // FIXME: Warn on useless attributes 1310 Decl *TagD = 0; 1311 TagDecl *Tag = 0; 1312 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1313 DS.getTypeSpecType() == DeclSpec::TST_struct || 1314 DS.getTypeSpecType() == DeclSpec::TST_union || 1315 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1316 TagD = static_cast<Decl *>(DS.getTypeRep()); 1317 1318 if (!TagD) // We probably had an error 1319 return DeclPtrTy(); 1320 1321 // Note that the above type specs guarantee that the 1322 // type rep is a Decl, whereas in many of the others 1323 // it's a Type. 1324 Tag = dyn_cast<TagDecl>(TagD); 1325 } 1326 1327 if (DS.isFriendSpecified()) { 1328 // If we're dealing with a class template decl, assume that the 1329 // template routines are handling it. 1330 if (TagD && isa<ClassTemplateDecl>(TagD)) 1331 return DeclPtrTy(); 1332 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1333 } 1334 1335 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1336 // If there are attributes in the DeclSpec, apply them to the record. 1337 if (const AttributeList *AL = DS.getAttributes()) 1338 ProcessDeclAttributeList(S, Record, AL); 1339 1340 if (!Record->getDeclName() && Record->isDefinition() && 1341 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1342 if (getLangOptions().CPlusPlus || 1343 Record->getDeclContext()->isRecord()) 1344 return BuildAnonymousStructOrUnion(S, DS, Record); 1345 1346 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1347 << DS.getSourceRange(); 1348 } 1349 1350 // Microsoft allows unnamed struct/union fields. Don't complain 1351 // about them. 1352 // FIXME: Should we support Microsoft's extensions in this area? 1353 if (Record->getDeclName() && getLangOptions().Microsoft) 1354 return DeclPtrTy::make(Tag); 1355 } 1356 1357 if (!DS.isMissingDeclaratorOk() && 1358 DS.getTypeSpecType() != DeclSpec::TST_error) { 1359 // Warn about typedefs of enums without names, since this is an 1360 // extension in both Microsoft an GNU. 1361 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1362 Tag && isa<EnumDecl>(Tag)) { 1363 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1364 << DS.getSourceRange(); 1365 return DeclPtrTy::make(Tag); 1366 } 1367 1368 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1369 << DS.getSourceRange(); 1370 return DeclPtrTy(); 1371 } 1372 1373 return DeclPtrTy::make(Tag); 1374} 1375 1376/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1377/// anonymous struct or union AnonRecord into the owning context Owner 1378/// and scope S. This routine will be invoked just after we realize 1379/// that an unnamed union or struct is actually an anonymous union or 1380/// struct, e.g., 1381/// 1382/// @code 1383/// union { 1384/// int i; 1385/// float f; 1386/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1387/// // f into the surrounding scope.x 1388/// @endcode 1389/// 1390/// This routine is recursive, injecting the names of nested anonymous 1391/// structs/unions into the owning context and scope as well. 1392bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1393 RecordDecl *AnonRecord) { 1394 bool Invalid = false; 1395 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1396 FEnd = AnonRecord->field_end(); 1397 F != FEnd; ++F) { 1398 if ((*F)->getDeclName()) { 1399 LookupResult R; 1400 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1401 LookupOrdinaryName, true); 1402 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1403 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1404 // C++ [class.union]p2: 1405 // The names of the members of an anonymous union shall be 1406 // distinct from the names of any other entity in the 1407 // scope in which the anonymous union is declared. 1408 unsigned diagKind 1409 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1410 : diag::err_anonymous_struct_member_redecl; 1411 Diag((*F)->getLocation(), diagKind) 1412 << (*F)->getDeclName(); 1413 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1414 Invalid = true; 1415 } else { 1416 // C++ [class.union]p2: 1417 // For the purpose of name lookup, after the anonymous union 1418 // definition, the members of the anonymous union are 1419 // considered to have been defined in the scope in which the 1420 // anonymous union is declared. 1421 Owner->makeDeclVisibleInContext(*F); 1422 S->AddDecl(DeclPtrTy::make(*F)); 1423 IdResolver.AddDecl(*F); 1424 } 1425 } else if (const RecordType *InnerRecordType 1426 = (*F)->getType()->getAs<RecordType>()) { 1427 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1428 if (InnerRecord->isAnonymousStructOrUnion()) 1429 Invalid = Invalid || 1430 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1431 } 1432 } 1433 1434 return Invalid; 1435} 1436 1437/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1438/// anonymous structure or union. Anonymous unions are a C++ feature 1439/// (C++ [class.union]) and a GNU C extension; anonymous structures 1440/// are a GNU C and GNU C++ extension. 1441Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1442 RecordDecl *Record) { 1443 DeclContext *Owner = Record->getDeclContext(); 1444 1445 // Diagnose whether this anonymous struct/union is an extension. 1446 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1447 Diag(Record->getLocation(), diag::ext_anonymous_union); 1448 else if (!Record->isUnion()) 1449 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1450 1451 // C and C++ require different kinds of checks for anonymous 1452 // structs/unions. 1453 bool Invalid = false; 1454 if (getLangOptions().CPlusPlus) { 1455 const char* PrevSpec = 0; 1456 unsigned DiagID; 1457 // C++ [class.union]p3: 1458 // Anonymous unions declared in a named namespace or in the 1459 // global namespace shall be declared static. 1460 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1461 (isa<TranslationUnitDecl>(Owner) || 1462 (isa<NamespaceDecl>(Owner) && 1463 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1464 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1465 Invalid = true; 1466 1467 // Recover by adding 'static'. 1468 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1469 PrevSpec, DiagID); 1470 } 1471 // C++ [class.union]p3: 1472 // A storage class is not allowed in a declaration of an 1473 // anonymous union in a class scope. 1474 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1475 isa<RecordDecl>(Owner)) { 1476 Diag(DS.getStorageClassSpecLoc(), 1477 diag::err_anonymous_union_with_storage_spec); 1478 Invalid = true; 1479 1480 // Recover by removing the storage specifier. 1481 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1482 PrevSpec, DiagID); 1483 } 1484 1485 // C++ [class.union]p2: 1486 // The member-specification of an anonymous union shall only 1487 // define non-static data members. [Note: nested types and 1488 // functions cannot be declared within an anonymous union. ] 1489 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1490 MemEnd = Record->decls_end(); 1491 Mem != MemEnd; ++Mem) { 1492 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1493 // C++ [class.union]p3: 1494 // An anonymous union shall not have private or protected 1495 // members (clause 11). 1496 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1497 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1498 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1499 Invalid = true; 1500 } 1501 } else if ((*Mem)->isImplicit()) { 1502 // Any implicit members are fine. 1503 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1504 // This is a type that showed up in an 1505 // elaborated-type-specifier inside the anonymous struct or 1506 // union, but which actually declares a type outside of the 1507 // anonymous struct or union. It's okay. 1508 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1509 if (!MemRecord->isAnonymousStructOrUnion() && 1510 MemRecord->getDeclName()) { 1511 // This is a nested type declaration. 1512 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1513 << (int)Record->isUnion(); 1514 Invalid = true; 1515 } 1516 } else { 1517 // We have something that isn't a non-static data 1518 // member. Complain about it. 1519 unsigned DK = diag::err_anonymous_record_bad_member; 1520 if (isa<TypeDecl>(*Mem)) 1521 DK = diag::err_anonymous_record_with_type; 1522 else if (isa<FunctionDecl>(*Mem)) 1523 DK = diag::err_anonymous_record_with_function; 1524 else if (isa<VarDecl>(*Mem)) 1525 DK = diag::err_anonymous_record_with_static; 1526 Diag((*Mem)->getLocation(), DK) 1527 << (int)Record->isUnion(); 1528 Invalid = true; 1529 } 1530 } 1531 } 1532 1533 if (!Record->isUnion() && !Owner->isRecord()) { 1534 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1535 << (int)getLangOptions().CPlusPlus; 1536 Invalid = true; 1537 } 1538 1539 // Mock up a declarator. 1540 Declarator Dc(DS, Declarator::TypeNameContext); 1541 DeclaratorInfo *DInfo = 0; 1542 GetTypeForDeclarator(Dc, S, &DInfo); 1543 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1544 1545 // Create a declaration for this anonymous struct/union. 1546 NamedDecl *Anon = 0; 1547 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1548 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1549 /*IdentifierInfo=*/0, 1550 Context.getTypeDeclType(Record), 1551 DInfo, 1552 /*BitWidth=*/0, /*Mutable=*/false); 1553 Anon->setAccess(AS_public); 1554 if (getLangOptions().CPlusPlus) 1555 FieldCollector->Add(cast<FieldDecl>(Anon)); 1556 } else { 1557 VarDecl::StorageClass SC; 1558 switch (DS.getStorageClassSpec()) { 1559 default: assert(0 && "Unknown storage class!"); 1560 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1561 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1562 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1563 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1564 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1565 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1566 case DeclSpec::SCS_mutable: 1567 // mutable can only appear on non-static class members, so it's always 1568 // an error here 1569 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1570 Invalid = true; 1571 SC = VarDecl::None; 1572 break; 1573 } 1574 1575 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1576 /*IdentifierInfo=*/0, 1577 Context.getTypeDeclType(Record), 1578 DInfo, 1579 SC); 1580 } 1581 Anon->setImplicit(); 1582 1583 // Add the anonymous struct/union object to the current 1584 // context. We'll be referencing this object when we refer to one of 1585 // its members. 1586 Owner->addDecl(Anon); 1587 1588 // Inject the members of the anonymous struct/union into the owning 1589 // context and into the identifier resolver chain for name lookup 1590 // purposes. 1591 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1592 Invalid = true; 1593 1594 // Mark this as an anonymous struct/union type. Note that we do not 1595 // do this until after we have already checked and injected the 1596 // members of this anonymous struct/union type, because otherwise 1597 // the members could be injected twice: once by DeclContext when it 1598 // builds its lookup table, and once by 1599 // InjectAnonymousStructOrUnionMembers. 1600 Record->setAnonymousStructOrUnion(true); 1601 1602 if (Invalid) 1603 Anon->setInvalidDecl(); 1604 1605 return DeclPtrTy::make(Anon); 1606} 1607 1608 1609/// GetNameForDeclarator - Determine the full declaration name for the 1610/// given Declarator. 1611DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1612 return GetNameFromUnqualifiedId(D.getName()); 1613} 1614 1615/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1616DeclarationName Sema::GetNameFromUnqualifiedId(UnqualifiedId &Name) { 1617 switch (Name.getKind()) { 1618 case UnqualifiedId::IK_Identifier: 1619 return DeclarationName(Name.Identifier); 1620 1621 case UnqualifiedId::IK_OperatorFunctionId: 1622 return Context.DeclarationNames.getCXXOperatorName( 1623 Name.OperatorFunctionId.Operator); 1624 1625 case UnqualifiedId::IK_ConversionFunctionId: { 1626 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1627 if (Ty.isNull()) 1628 return DeclarationName(); 1629 1630 return Context.DeclarationNames.getCXXConversionFunctionName( 1631 Context.getCanonicalType(Ty)); 1632 } 1633 1634 case UnqualifiedId::IK_ConstructorName: { 1635 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1636 if (Ty.isNull()) 1637 return DeclarationName(); 1638 1639 return Context.DeclarationNames.getCXXConstructorName( 1640 Context.getCanonicalType(Ty)); 1641 } 1642 1643 case UnqualifiedId::IK_DestructorName: { 1644 QualType Ty = GetTypeFromParser(Name.DestructorName); 1645 if (Ty.isNull()) 1646 return DeclarationName(); 1647 1648 return Context.DeclarationNames.getCXXDestructorName( 1649 Context.getCanonicalType(Ty)); 1650 } 1651 1652 case UnqualifiedId::IK_TemplateId: { 1653 TemplateName TName 1654 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1655 if (TemplateDecl *Template = TName.getAsTemplateDecl()) 1656 return Template->getDeclName(); 1657 if (OverloadedFunctionDecl *Ovl = TName.getAsOverloadedFunctionDecl()) 1658 return Ovl->getDeclName(); 1659 1660 return DeclarationName(); 1661 } 1662 } 1663 1664 assert(false && "Unknown name kind"); 1665 return DeclarationName(); 1666} 1667 1668/// isNearlyMatchingFunction - Determine whether the C++ functions 1669/// Declaration and Definition are "nearly" matching. This heuristic 1670/// is used to improve diagnostics in the case where an out-of-line 1671/// function definition doesn't match any declaration within 1672/// the class or namespace. 1673static bool isNearlyMatchingFunction(ASTContext &Context, 1674 FunctionDecl *Declaration, 1675 FunctionDecl *Definition) { 1676 if (Declaration->param_size() != Definition->param_size()) 1677 return false; 1678 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1679 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1680 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1681 1682 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1683 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1684 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1685 return false; 1686 } 1687 1688 return true; 1689} 1690 1691Sema::DeclPtrTy 1692Sema::HandleDeclarator(Scope *S, Declarator &D, 1693 MultiTemplateParamsArg TemplateParamLists, 1694 bool IsFunctionDefinition) { 1695 DeclarationName Name = GetNameForDeclarator(D); 1696 1697 // All of these full declarators require an identifier. If it doesn't have 1698 // one, the ParsedFreeStandingDeclSpec action should be used. 1699 if (!Name) { 1700 if (!D.isInvalidType()) // Reject this if we think it is valid. 1701 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1702 diag::err_declarator_need_ident) 1703 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1704 return DeclPtrTy(); 1705 } 1706 1707 // The scope passed in may not be a decl scope. Zip up the scope tree until 1708 // we find one that is. 1709 while ((S->getFlags() & Scope::DeclScope) == 0 || 1710 (S->getFlags() & Scope::TemplateParamScope) != 0) 1711 S = S->getParent(); 1712 1713 // If this is an out-of-line definition of a member of a class template 1714 // or class template partial specialization, we may need to rebuild the 1715 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1716 // for more information. 1717 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1718 // handle expressions properly. 1719 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1720 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1721 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1722 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1723 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1724 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1725 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1726 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1727 // FIXME: Preserve type source info. 1728 QualType T = GetTypeFromParser(DS.getTypeRep()); 1729 EnterDeclaratorContext(S, DC); 1730 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1731 ExitDeclaratorContext(S); 1732 if (T.isNull()) 1733 return DeclPtrTy(); 1734 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1735 } 1736 } 1737 1738 DeclContext *DC; 1739 NamedDecl *PrevDecl; 1740 NamedDecl *New; 1741 1742 DeclaratorInfo *DInfo = 0; 1743 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1744 1745 // See if this is a redefinition of a variable in the same scope. 1746 if (D.getCXXScopeSpec().isInvalid()) { 1747 DC = CurContext; 1748 PrevDecl = 0; 1749 D.setInvalidType(); 1750 } else if (!D.getCXXScopeSpec().isSet()) { 1751 LookupNameKind NameKind = LookupOrdinaryName; 1752 1753 // If the declaration we're planning to build will be a function 1754 // or object with linkage, then look for another declaration with 1755 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1756 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1757 /* Do nothing*/; 1758 else if (R->isFunctionType()) { 1759 if (CurContext->isFunctionOrMethod() || 1760 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1761 NameKind = LookupRedeclarationWithLinkage; 1762 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1763 NameKind = LookupRedeclarationWithLinkage; 1764 else if (CurContext->getLookupContext()->isTranslationUnit() && 1765 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1766 NameKind = LookupRedeclarationWithLinkage; 1767 1768 DC = CurContext; 1769 LookupResult R; 1770 LookupName(R, S, Name, NameKind, true, 1771 NameKind == LookupRedeclarationWithLinkage, 1772 D.getIdentifierLoc()); 1773 PrevDecl = R.getAsSingleDecl(Context); 1774 } else { // Something like "int foo::x;" 1775 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1776 1777 if (!DC) { 1778 // If we could not compute the declaration context, it's because the 1779 // declaration context is dependent but does not refer to a class, 1780 // class template, or class template partial specialization. Complain 1781 // and return early, to avoid the coming semantic disaster. 1782 Diag(D.getIdentifierLoc(), 1783 diag::err_template_qualified_declarator_no_match) 1784 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1785 << D.getCXXScopeSpec().getRange(); 1786 return DeclPtrTy(); 1787 } 1788 1789 if (!DC->isDependentContext() && 1790 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1791 return DeclPtrTy(); 1792 1793 LookupResult Res; 1794 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1795 PrevDecl = Res.getAsSingleDecl(Context); 1796 1797 // C++ 7.3.1.2p2: 1798 // Members (including explicit specializations of templates) of a named 1799 // namespace can also be defined outside that namespace by explicit 1800 // qualification of the name being defined, provided that the entity being 1801 // defined was already declared in the namespace and the definition appears 1802 // after the point of declaration in a namespace that encloses the 1803 // declarations namespace. 1804 // 1805 // Note that we only check the context at this point. We don't yet 1806 // have enough information to make sure that PrevDecl is actually 1807 // the declaration we want to match. For example, given: 1808 // 1809 // class X { 1810 // void f(); 1811 // void f(float); 1812 // }; 1813 // 1814 // void X::f(int) { } // ill-formed 1815 // 1816 // In this case, PrevDecl will point to the overload set 1817 // containing the two f's declared in X, but neither of them 1818 // matches. 1819 1820 // First check whether we named the global scope. 1821 if (isa<TranslationUnitDecl>(DC)) { 1822 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1823 << Name << D.getCXXScopeSpec().getRange(); 1824 } else if (!CurContext->Encloses(DC)) { 1825 // The qualifying scope doesn't enclose the original declaration. 1826 // Emit diagnostic based on current scope. 1827 SourceLocation L = D.getIdentifierLoc(); 1828 SourceRange R = D.getCXXScopeSpec().getRange(); 1829 if (isa<FunctionDecl>(CurContext)) 1830 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1831 else 1832 Diag(L, diag::err_invalid_declarator_scope) 1833 << Name << cast<NamedDecl>(DC) << R; 1834 D.setInvalidType(); 1835 } 1836 } 1837 1838 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1839 // Maybe we will complain about the shadowed template parameter. 1840 if (!D.isInvalidType()) 1841 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1842 D.setInvalidType(); 1843 1844 // Just pretend that we didn't see the previous declaration. 1845 PrevDecl = 0; 1846 } 1847 1848 // In C++, the previous declaration we find might be a tag type 1849 // (class or enum). In this case, the new declaration will hide the 1850 // tag type. Note that this does does not apply if we're declaring a 1851 // typedef (C++ [dcl.typedef]p4). 1852 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1853 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1854 PrevDecl = 0; 1855 1856 bool Redeclaration = false; 1857 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1858 if (TemplateParamLists.size()) { 1859 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1860 return DeclPtrTy(); 1861 } 1862 1863 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1864 } else if (R->isFunctionType()) { 1865 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1866 move(TemplateParamLists), 1867 IsFunctionDefinition, Redeclaration); 1868 } else { 1869 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1870 move(TemplateParamLists), 1871 Redeclaration); 1872 } 1873 1874 if (New == 0) 1875 return DeclPtrTy(); 1876 1877 // If this has an identifier and is not an invalid redeclaration or 1878 // function template specialization, add it to the scope stack. 1879 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1880 !(isa<FunctionDecl>(New) && 1881 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1882 PushOnScopeChains(New, S); 1883 1884 return DeclPtrTy::make(New); 1885} 1886 1887/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1888/// types into constant array types in certain situations which would otherwise 1889/// be errors (for GCC compatibility). 1890static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1891 ASTContext &Context, 1892 bool &SizeIsNegative) { 1893 // This method tries to turn a variable array into a constant 1894 // array even when the size isn't an ICE. This is necessary 1895 // for compatibility with code that depends on gcc's buggy 1896 // constant expression folding, like struct {char x[(int)(char*)2];} 1897 SizeIsNegative = false; 1898 1899 QualifierCollector Qs; 1900 const Type *Ty = Qs.strip(T); 1901 1902 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1903 QualType Pointee = PTy->getPointeeType(); 1904 QualType FixedType = 1905 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1906 if (FixedType.isNull()) return FixedType; 1907 FixedType = Context.getPointerType(FixedType); 1908 return Qs.apply(FixedType); 1909 } 1910 1911 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1912 if (!VLATy) 1913 return QualType(); 1914 // FIXME: We should probably handle this case 1915 if (VLATy->getElementType()->isVariablyModifiedType()) 1916 return QualType(); 1917 1918 Expr::EvalResult EvalResult; 1919 if (!VLATy->getSizeExpr() || 1920 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1921 !EvalResult.Val.isInt()) 1922 return QualType(); 1923 1924 llvm::APSInt &Res = EvalResult.Val.getInt(); 1925 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1926 // TODO: preserve the size expression in declarator info 1927 return Context.getConstantArrayType(VLATy->getElementType(), 1928 Res, ArrayType::Normal, 0); 1929 } 1930 1931 SizeIsNegative = true; 1932 return QualType(); 1933} 1934 1935/// \brief Register the given locally-scoped external C declaration so 1936/// that it can be found later for redeclarations 1937void 1938Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1939 Scope *S) { 1940 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1941 "Decl is not a locally-scoped decl!"); 1942 // Note that we have a locally-scoped external with this name. 1943 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1944 1945 if (!PrevDecl) 1946 return; 1947 1948 // If there was a previous declaration of this variable, it may be 1949 // in our identifier chain. Update the identifier chain with the new 1950 // declaration. 1951 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1952 // The previous declaration was found on the identifer resolver 1953 // chain, so remove it from its scope. 1954 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1955 S = S->getParent(); 1956 1957 if (S) 1958 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1959 } 1960} 1961 1962/// \brief Diagnose function specifiers on a declaration of an identifier that 1963/// does not identify a function. 1964void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1965 // FIXME: We should probably indicate the identifier in question to avoid 1966 // confusion for constructs like "inline int a(), b;" 1967 if (D.getDeclSpec().isInlineSpecified()) 1968 Diag(D.getDeclSpec().getInlineSpecLoc(), 1969 diag::err_inline_non_function); 1970 1971 if (D.getDeclSpec().isVirtualSpecified()) 1972 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1973 diag::err_virtual_non_function); 1974 1975 if (D.getDeclSpec().isExplicitSpecified()) 1976 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1977 diag::err_explicit_non_function); 1978} 1979 1980NamedDecl* 1981Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1982 QualType R, DeclaratorInfo *DInfo, 1983 NamedDecl* PrevDecl, bool &Redeclaration) { 1984 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1985 if (D.getCXXScopeSpec().isSet()) { 1986 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1987 << D.getCXXScopeSpec().getRange(); 1988 D.setInvalidType(); 1989 // Pretend we didn't see the scope specifier. 1990 DC = 0; 1991 } 1992 1993 if (getLangOptions().CPlusPlus) { 1994 // Check that there are no default arguments (C++ only). 1995 CheckExtraCXXDefaultArguments(D); 1996 } 1997 1998 DiagnoseFunctionSpecifiers(D); 1999 2000 if (D.getDeclSpec().isThreadSpecified()) 2001 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2002 2003 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 2004 if (!NewTD) return 0; 2005 2006 // Handle attributes prior to checking for duplicates in MergeVarDecl 2007 ProcessDeclAttributes(S, NewTD, D); 2008 // Merge the decl with the existing one if appropriate. If the decl is 2009 // in an outer scope, it isn't the same thing. 2010 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2011 Redeclaration = true; 2012 MergeTypeDefDecl(NewTD, PrevDecl); 2013 } 2014 2015 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2016 // then it shall have block scope. 2017 QualType T = NewTD->getUnderlyingType(); 2018 if (T->isVariablyModifiedType()) { 2019 CurFunctionNeedsScopeChecking = true; 2020 2021 if (S->getFnParent() == 0) { 2022 bool SizeIsNegative; 2023 QualType FixedTy = 2024 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2025 if (!FixedTy.isNull()) { 2026 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2027 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2028 } else { 2029 if (SizeIsNegative) 2030 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2031 else if (T->isVariableArrayType()) 2032 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2033 else 2034 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2035 NewTD->setInvalidDecl(); 2036 } 2037 } 2038 } 2039 2040 // If this is the C FILE type, notify the AST context. 2041 if (IdentifierInfo *II = NewTD->getIdentifier()) 2042 if (!NewTD->isInvalidDecl() && 2043 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2044 if (II->isStr("FILE")) 2045 Context.setFILEDecl(NewTD); 2046 else if (II->isStr("jmp_buf")) 2047 Context.setjmp_bufDecl(NewTD); 2048 else if (II->isStr("sigjmp_buf")) 2049 Context.setsigjmp_bufDecl(NewTD); 2050 } 2051 2052 return NewTD; 2053} 2054 2055/// \brief Determines whether the given declaration is an out-of-scope 2056/// previous declaration. 2057/// 2058/// This routine should be invoked when name lookup has found a 2059/// previous declaration (PrevDecl) that is not in the scope where a 2060/// new declaration by the same name is being introduced. If the new 2061/// declaration occurs in a local scope, previous declarations with 2062/// linkage may still be considered previous declarations (C99 2063/// 6.2.2p4-5, C++ [basic.link]p6). 2064/// 2065/// \param PrevDecl the previous declaration found by name 2066/// lookup 2067/// 2068/// \param DC the context in which the new declaration is being 2069/// declared. 2070/// 2071/// \returns true if PrevDecl is an out-of-scope previous declaration 2072/// for a new delcaration with the same name. 2073static bool 2074isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2075 ASTContext &Context) { 2076 if (!PrevDecl) 2077 return 0; 2078 2079 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2080 // case we need to check each of the overloaded functions. 2081 if (!PrevDecl->hasLinkage()) 2082 return false; 2083 2084 if (Context.getLangOptions().CPlusPlus) { 2085 // C++ [basic.link]p6: 2086 // If there is a visible declaration of an entity with linkage 2087 // having the same name and type, ignoring entities declared 2088 // outside the innermost enclosing namespace scope, the block 2089 // scope declaration declares that same entity and receives the 2090 // linkage of the previous declaration. 2091 DeclContext *OuterContext = DC->getLookupContext(); 2092 if (!OuterContext->isFunctionOrMethod()) 2093 // This rule only applies to block-scope declarations. 2094 return false; 2095 else { 2096 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2097 if (PrevOuterContext->isRecord()) 2098 // We found a member function: ignore it. 2099 return false; 2100 else { 2101 // Find the innermost enclosing namespace for the new and 2102 // previous declarations. 2103 while (!OuterContext->isFileContext()) 2104 OuterContext = OuterContext->getParent(); 2105 while (!PrevOuterContext->isFileContext()) 2106 PrevOuterContext = PrevOuterContext->getParent(); 2107 2108 // The previous declaration is in a different namespace, so it 2109 // isn't the same function. 2110 if (OuterContext->getPrimaryContext() != 2111 PrevOuterContext->getPrimaryContext()) 2112 return false; 2113 } 2114 } 2115 } 2116 2117 return true; 2118} 2119 2120NamedDecl* 2121Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2122 QualType R, DeclaratorInfo *DInfo, 2123 NamedDecl* PrevDecl, 2124 MultiTemplateParamsArg TemplateParamLists, 2125 bool &Redeclaration) { 2126 DeclarationName Name = GetNameForDeclarator(D); 2127 2128 // Check that there are no default arguments (C++ only). 2129 if (getLangOptions().CPlusPlus) 2130 CheckExtraCXXDefaultArguments(D); 2131 2132 VarDecl *NewVD; 2133 VarDecl::StorageClass SC; 2134 switch (D.getDeclSpec().getStorageClassSpec()) { 2135 default: assert(0 && "Unknown storage class!"); 2136 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2137 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2138 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2139 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2140 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2141 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2142 case DeclSpec::SCS_mutable: 2143 // mutable can only appear on non-static class members, so it's always 2144 // an error here 2145 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2146 D.setInvalidType(); 2147 SC = VarDecl::None; 2148 break; 2149 } 2150 2151 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2152 if (!II) { 2153 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2154 << Name.getAsString(); 2155 return 0; 2156 } 2157 2158 DiagnoseFunctionSpecifiers(D); 2159 2160 if (!DC->isRecord() && S->getFnParent() == 0) { 2161 // C99 6.9p2: The storage-class specifiers auto and register shall not 2162 // appear in the declaration specifiers in an external declaration. 2163 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2164 2165 // If this is a register variable with an asm label specified, then this 2166 // is a GNU extension. 2167 if (SC == VarDecl::Register && D.getAsmLabel()) 2168 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2169 else 2170 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2171 D.setInvalidType(); 2172 } 2173 } 2174 if (DC->isRecord() && !CurContext->isRecord()) { 2175 // This is an out-of-line definition of a static data member. 2176 if (SC == VarDecl::Static) { 2177 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2178 diag::err_static_out_of_line) 2179 << CodeModificationHint::CreateRemoval( 2180 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2181 } else if (SC == VarDecl::None) 2182 SC = VarDecl::Static; 2183 } 2184 if (SC == VarDecl::Static) { 2185 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2186 if (RD->isLocalClass()) 2187 Diag(D.getIdentifierLoc(), 2188 diag::err_static_data_member_not_allowed_in_local_class) 2189 << Name << RD->getDeclName(); 2190 } 2191 } 2192 2193 // Match up the template parameter lists with the scope specifier, then 2194 // determine whether we have a template or a template specialization. 2195 bool isExplicitSpecialization = false; 2196 if (TemplateParameterList *TemplateParams 2197 = MatchTemplateParametersToScopeSpecifier( 2198 D.getDeclSpec().getSourceRange().getBegin(), 2199 D.getCXXScopeSpec(), 2200 (TemplateParameterList**)TemplateParamLists.get(), 2201 TemplateParamLists.size(), 2202 isExplicitSpecialization)) { 2203 if (TemplateParams->size() > 0) { 2204 // There is no such thing as a variable template. 2205 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2206 << II 2207 << SourceRange(TemplateParams->getTemplateLoc(), 2208 TemplateParams->getRAngleLoc()); 2209 return 0; 2210 } else { 2211 // There is an extraneous 'template<>' for this variable. Complain 2212 // about it, but allow the declaration of the variable. 2213 Diag(TemplateParams->getTemplateLoc(), 2214 diag::err_template_variable_noparams) 2215 << II 2216 << SourceRange(TemplateParams->getTemplateLoc(), 2217 TemplateParams->getRAngleLoc()); 2218 2219 isExplicitSpecialization = true; 2220 } 2221 } 2222 2223 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2224 II, R, DInfo, SC); 2225 2226 if (D.isInvalidType()) 2227 NewVD->setInvalidDecl(); 2228 2229 if (D.getDeclSpec().isThreadSpecified()) { 2230 if (NewVD->hasLocalStorage()) 2231 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2232 else if (!Context.Target.isTLSSupported()) 2233 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2234 else 2235 NewVD->setThreadSpecified(true); 2236 } 2237 2238 // Set the lexical context. If the declarator has a C++ scope specifier, the 2239 // lexical context will be different from the semantic context. 2240 NewVD->setLexicalDeclContext(CurContext); 2241 2242 // Handle attributes prior to checking for duplicates in MergeVarDecl 2243 ProcessDeclAttributes(S, NewVD, D); 2244 2245 // Handle GNU asm-label extension (encoded as an attribute). 2246 if (Expr *E = (Expr*) D.getAsmLabel()) { 2247 // The parser guarantees this is a string. 2248 StringLiteral *SE = cast<StringLiteral>(E); 2249 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2250 SE->getByteLength()))); 2251 } 2252 2253 // If name lookup finds a previous declaration that is not in the 2254 // same scope as the new declaration, this may still be an 2255 // acceptable redeclaration. 2256 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2257 !(NewVD->hasLinkage() && 2258 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2259 PrevDecl = 0; 2260 2261 // Merge the decl with the existing one if appropriate. 2262 if (PrevDecl) { 2263 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2264 // The user tried to define a non-static data member 2265 // out-of-line (C++ [dcl.meaning]p1). 2266 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2267 << D.getCXXScopeSpec().getRange(); 2268 PrevDecl = 0; 2269 NewVD->setInvalidDecl(); 2270 } 2271 } else if (D.getCXXScopeSpec().isSet()) { 2272 // No previous declaration in the qualifying scope. 2273 Diag(D.getIdentifierLoc(), diag::err_no_member) 2274 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2275 << D.getCXXScopeSpec().getRange(); 2276 NewVD->setInvalidDecl(); 2277 } 2278 2279 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2280 2281 // This is an explicit specialization of a static data member. Check it. 2282 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2283 CheckMemberSpecialization(NewVD, PrevDecl)) 2284 NewVD->setInvalidDecl(); 2285 2286 // attributes declared post-definition are currently ignored 2287 if (PrevDecl) { 2288 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2289 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2290 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2291 Diag(Def->getLocation(), diag::note_previous_definition); 2292 } 2293 } 2294 2295 // If this is a locally-scoped extern C variable, update the map of 2296 // such variables. 2297 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2298 !NewVD->isInvalidDecl()) 2299 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2300 2301 return NewVD; 2302} 2303 2304/// \brief Perform semantic checking on a newly-created variable 2305/// declaration. 2306/// 2307/// This routine performs all of the type-checking required for a 2308/// variable declaration once it has been built. It is used both to 2309/// check variables after they have been parsed and their declarators 2310/// have been translated into a declaration, and to check variables 2311/// that have been instantiated from a template. 2312/// 2313/// Sets NewVD->isInvalidDecl() if an error was encountered. 2314void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2315 bool &Redeclaration) { 2316 // If the decl is already known invalid, don't check it. 2317 if (NewVD->isInvalidDecl()) 2318 return; 2319 2320 QualType T = NewVD->getType(); 2321 2322 if (T->isObjCInterfaceType()) { 2323 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2324 return NewVD->setInvalidDecl(); 2325 } 2326 2327 // The variable can not have an abstract class type. 2328 if (RequireNonAbstractType(NewVD->getLocation(), T, 2329 diag::err_abstract_type_in_decl, 2330 AbstractVariableType)) 2331 return NewVD->setInvalidDecl(); 2332 2333 // Emit an error if an address space was applied to decl with local storage. 2334 // This includes arrays of objects with address space qualifiers, but not 2335 // automatic variables that point to other address spaces. 2336 // ISO/IEC TR 18037 S5.1.2 2337 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2338 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2339 return NewVD->setInvalidDecl(); 2340 } 2341 2342 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2343 && !NewVD->hasAttr<BlocksAttr>()) 2344 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2345 2346 bool isVM = T->isVariablyModifiedType(); 2347 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2348 NewVD->hasAttr<BlocksAttr>()) 2349 CurFunctionNeedsScopeChecking = true; 2350 2351 if ((isVM && NewVD->hasLinkage()) || 2352 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2353 bool SizeIsNegative; 2354 QualType FixedTy = 2355 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2356 2357 if (FixedTy.isNull() && T->isVariableArrayType()) { 2358 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2359 // FIXME: This won't give the correct result for 2360 // int a[10][n]; 2361 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2362 2363 if (NewVD->isFileVarDecl()) 2364 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2365 << SizeRange; 2366 else if (NewVD->getStorageClass() == VarDecl::Static) 2367 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2368 << SizeRange; 2369 else 2370 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2371 << SizeRange; 2372 return NewVD->setInvalidDecl(); 2373 } 2374 2375 if (FixedTy.isNull()) { 2376 if (NewVD->isFileVarDecl()) 2377 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2378 else 2379 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2380 return NewVD->setInvalidDecl(); 2381 } 2382 2383 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2384 NewVD->setType(FixedTy); 2385 } 2386 2387 if (!PrevDecl && NewVD->isExternC()) { 2388 // Since we did not find anything by this name and we're declaring 2389 // an extern "C" variable, look for a non-visible extern "C" 2390 // declaration with the same name. 2391 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2392 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2393 if (Pos != LocallyScopedExternalDecls.end()) 2394 PrevDecl = Pos->second; 2395 } 2396 2397 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2398 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2399 << T; 2400 return NewVD->setInvalidDecl(); 2401 } 2402 2403 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2404 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2405 return NewVD->setInvalidDecl(); 2406 } 2407 2408 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2409 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2410 return NewVD->setInvalidDecl(); 2411 } 2412 2413 if (PrevDecl) { 2414 Redeclaration = true; 2415 MergeVarDecl(NewVD, PrevDecl); 2416 } 2417} 2418 2419static bool isUsingDecl(Decl *D) { 2420 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2421} 2422 2423/// \brief Data used with FindOverriddenMethod 2424struct FindOverriddenMethodData { 2425 Sema *S; 2426 CXXMethodDecl *Method; 2427}; 2428 2429/// \brief Member lookup function that determines whether a given C++ 2430/// method overrides a method in a base class, to be used with 2431/// CXXRecordDecl::lookupInBases(). 2432static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2433 CXXBasePath &Path, 2434 void *UserData) { 2435 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2436 2437 FindOverriddenMethodData *Data 2438 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2439 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2440 Path.Decls.first != Path.Decls.second; 2441 ++Path.Decls.first) { 2442 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2443 OverloadedFunctionDecl::function_iterator MatchedDecl; 2444 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2445 return true; 2446 } 2447 } 2448 2449 return false; 2450} 2451 2452NamedDecl* 2453Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2454 QualType R, DeclaratorInfo *DInfo, 2455 NamedDecl* PrevDecl, 2456 MultiTemplateParamsArg TemplateParamLists, 2457 bool IsFunctionDefinition, bool &Redeclaration) { 2458 assert(R.getTypePtr()->isFunctionType()); 2459 2460 DeclarationName Name = GetNameForDeclarator(D); 2461 FunctionDecl::StorageClass SC = FunctionDecl::None; 2462 switch (D.getDeclSpec().getStorageClassSpec()) { 2463 default: assert(0 && "Unknown storage class!"); 2464 case DeclSpec::SCS_auto: 2465 case DeclSpec::SCS_register: 2466 case DeclSpec::SCS_mutable: 2467 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2468 diag::err_typecheck_sclass_func); 2469 D.setInvalidType(); 2470 break; 2471 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2472 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2473 case DeclSpec::SCS_static: { 2474 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2475 // C99 6.7.1p5: 2476 // The declaration of an identifier for a function that has 2477 // block scope shall have no explicit storage-class specifier 2478 // other than extern 2479 // See also (C++ [dcl.stc]p4). 2480 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2481 diag::err_static_block_func); 2482 SC = FunctionDecl::None; 2483 } else 2484 SC = FunctionDecl::Static; 2485 break; 2486 } 2487 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2488 } 2489 2490 if (D.getDeclSpec().isThreadSpecified()) 2491 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2492 2493 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2494 bool isInline = D.getDeclSpec().isInlineSpecified(); 2495 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2496 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2497 2498 // Check that the return type is not an abstract class type. 2499 // For record types, this is done by the AbstractClassUsageDiagnoser once 2500 // the class has been completely parsed. 2501 if (!DC->isRecord() && 2502 RequireNonAbstractType(D.getIdentifierLoc(), 2503 R->getAs<FunctionType>()->getResultType(), 2504 diag::err_abstract_type_in_decl, 2505 AbstractReturnType)) 2506 D.setInvalidType(); 2507 2508 // Do not allow returning a objc interface by-value. 2509 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2510 Diag(D.getIdentifierLoc(), 2511 diag::err_object_cannot_be_passed_returned_by_value) << 0 2512 << R->getAs<FunctionType>()->getResultType(); 2513 D.setInvalidType(); 2514 } 2515 2516 bool isVirtualOkay = false; 2517 FunctionDecl *NewFD; 2518 2519 if (isFriend) { 2520 // DC is the namespace in which the function is being declared. 2521 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2522 "friend function being created in a non-namespace context"); 2523 2524 // C++ [class.friend]p5 2525 // A function can be defined in a friend declaration of a 2526 // class . . . . Such a function is implicitly inline. 2527 isInline |= IsFunctionDefinition; 2528 } 2529 2530 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2531 // This is a C++ constructor declaration. 2532 assert(DC->isRecord() && 2533 "Constructors can only be declared in a member context"); 2534 2535 R = CheckConstructorDeclarator(D, R, SC); 2536 2537 // Create the new declaration 2538 NewFD = CXXConstructorDecl::Create(Context, 2539 cast<CXXRecordDecl>(DC), 2540 D.getIdentifierLoc(), Name, R, DInfo, 2541 isExplicit, isInline, 2542 /*isImplicitlyDeclared=*/false); 2543 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2544 // This is a C++ destructor declaration. 2545 if (DC->isRecord()) { 2546 R = CheckDestructorDeclarator(D, SC); 2547 2548 NewFD = CXXDestructorDecl::Create(Context, 2549 cast<CXXRecordDecl>(DC), 2550 D.getIdentifierLoc(), Name, R, 2551 isInline, 2552 /*isImplicitlyDeclared=*/false); 2553 2554 isVirtualOkay = true; 2555 } else { 2556 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2557 2558 // Create a FunctionDecl to satisfy the function definition parsing 2559 // code path. 2560 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2561 Name, R, DInfo, SC, isInline, 2562 /*hasPrototype=*/true); 2563 D.setInvalidType(); 2564 } 2565 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2566 if (!DC->isRecord()) { 2567 Diag(D.getIdentifierLoc(), 2568 diag::err_conv_function_not_member); 2569 return 0; 2570 } 2571 2572 CheckConversionDeclarator(D, R, SC); 2573 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2574 D.getIdentifierLoc(), Name, R, DInfo, 2575 isInline, isExplicit); 2576 2577 isVirtualOkay = true; 2578 } else if (DC->isRecord()) { 2579 // If the of the function is the same as the name of the record, then this 2580 // must be an invalid constructor that has a return type. 2581 // (The parser checks for a return type and makes the declarator a 2582 // constructor if it has no return type). 2583 // must have an invalid constructor that has a return type 2584 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2585 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2586 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2587 << SourceRange(D.getIdentifierLoc()); 2588 return 0; 2589 } 2590 2591 // This is a C++ method declaration. 2592 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2593 D.getIdentifierLoc(), Name, R, DInfo, 2594 (SC == FunctionDecl::Static), isInline); 2595 2596 isVirtualOkay = (SC != FunctionDecl::Static); 2597 } else { 2598 // Determine whether the function was written with a 2599 // prototype. This true when: 2600 // - we're in C++ (where every function has a prototype), 2601 // - there is a prototype in the declarator, or 2602 // - the type R of the function is some kind of typedef or other reference 2603 // to a type name (which eventually refers to a function type). 2604 bool HasPrototype = 2605 getLangOptions().CPlusPlus || 2606 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2607 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2608 2609 NewFD = FunctionDecl::Create(Context, DC, 2610 D.getIdentifierLoc(), 2611 Name, R, DInfo, SC, isInline, HasPrototype); 2612 } 2613 2614 if (D.isInvalidType()) 2615 NewFD->setInvalidDecl(); 2616 2617 // Set the lexical context. If the declarator has a C++ 2618 // scope specifier, or is the object of a friend declaration, the 2619 // lexical context will be different from the semantic context. 2620 NewFD->setLexicalDeclContext(CurContext); 2621 2622 // Match up the template parameter lists with the scope specifier, then 2623 // determine whether we have a template or a template specialization. 2624 FunctionTemplateDecl *FunctionTemplate = 0; 2625 bool isExplicitSpecialization = false; 2626 bool isFunctionTemplateSpecialization = false; 2627 if (TemplateParameterList *TemplateParams 2628 = MatchTemplateParametersToScopeSpecifier( 2629 D.getDeclSpec().getSourceRange().getBegin(), 2630 D.getCXXScopeSpec(), 2631 (TemplateParameterList**)TemplateParamLists.get(), 2632 TemplateParamLists.size(), 2633 isExplicitSpecialization)) { 2634 if (TemplateParams->size() > 0) { 2635 // This is a function template 2636 2637 // Check that we can declare a template here. 2638 if (CheckTemplateDeclScope(S, TemplateParams)) 2639 return 0; 2640 2641 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2642 NewFD->getLocation(), 2643 Name, TemplateParams, 2644 NewFD); 2645 FunctionTemplate->setLexicalDeclContext(CurContext); 2646 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2647 } else { 2648 // This is a function template specialization. 2649 isFunctionTemplateSpecialization = true; 2650 } 2651 2652 // FIXME: Free this memory properly. 2653 TemplateParamLists.release(); 2654 } 2655 2656 // C++ [dcl.fct.spec]p5: 2657 // The virtual specifier shall only be used in declarations of 2658 // nonstatic class member functions that appear within a 2659 // member-specification of a class declaration; see 10.3. 2660 // 2661 if (isVirtual && !NewFD->isInvalidDecl()) { 2662 if (!isVirtualOkay) { 2663 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2664 diag::err_virtual_non_function); 2665 } else if (!CurContext->isRecord()) { 2666 // 'virtual' was specified outside of the class. 2667 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2668 << CodeModificationHint::CreateRemoval( 2669 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2670 } else { 2671 // Okay: Add virtual to the method. 2672 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2673 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2674 CurClass->setAggregate(false); 2675 CurClass->setPOD(false); 2676 CurClass->setEmpty(false); 2677 CurClass->setPolymorphic(true); 2678 CurClass->setHasTrivialConstructor(false); 2679 CurClass->setHasTrivialCopyConstructor(false); 2680 CurClass->setHasTrivialCopyAssignment(false); 2681 } 2682 } 2683 2684 if (isFriend) { 2685 if (FunctionTemplate) { 2686 FunctionTemplate->setObjectOfFriendDecl( 2687 /* PreviouslyDeclared= */ PrevDecl != NULL); 2688 FunctionTemplate->setAccess(AS_public); 2689 } 2690 else 2691 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2692 2693 NewFD->setAccess(AS_public); 2694 } 2695 2696 2697 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2698 // Look for virtual methods in base classes that this method might override. 2699 CXXBasePaths Paths; 2700 FindOverriddenMethodData Data; 2701 Data.Method = NewMD; 2702 Data.S = this; 2703 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2704 Paths)) { 2705 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2706 E = Paths.found_decls_end(); I != E; ++I) { 2707 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2708 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2709 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2710 NewMD->addOverriddenMethod(OldMD); 2711 } 2712 } 2713 } 2714 } 2715 2716 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2717 !CurContext->isRecord()) { 2718 // C++ [class.static]p1: 2719 // A data or function member of a class may be declared static 2720 // in a class definition, in which case it is a static member of 2721 // the class. 2722 2723 // Complain about the 'static' specifier if it's on an out-of-line 2724 // member function definition. 2725 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2726 diag::err_static_out_of_line) 2727 << CodeModificationHint::CreateRemoval( 2728 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2729 } 2730 2731 // Handle GNU asm-label extension (encoded as an attribute). 2732 if (Expr *E = (Expr*) D.getAsmLabel()) { 2733 // The parser guarantees this is a string. 2734 StringLiteral *SE = cast<StringLiteral>(E); 2735 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2736 SE->getByteLength()))); 2737 } 2738 2739 // Copy the parameter declarations from the declarator D to the function 2740 // declaration NewFD, if they are available. First scavenge them into Params. 2741 llvm::SmallVector<ParmVarDecl*, 16> Params; 2742 if (D.getNumTypeObjects() > 0) { 2743 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2744 2745 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2746 // function that takes no arguments, not a function that takes a 2747 // single void argument. 2748 // We let through "const void" here because Sema::GetTypeForDeclarator 2749 // already checks for that case. 2750 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2751 FTI.ArgInfo[0].Param && 2752 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2753 // Empty arg list, don't push any params. 2754 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2755 2756 // In C++, the empty parameter-type-list must be spelled "void"; a 2757 // typedef of void is not permitted. 2758 if (getLangOptions().CPlusPlus && 2759 Param->getType().getUnqualifiedType() != Context.VoidTy) 2760 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2761 // FIXME: Leaks decl? 2762 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2763 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2764 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2765 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2766 Param->setDeclContext(NewFD); 2767 Params.push_back(Param); 2768 } 2769 } 2770 2771 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2772 // When we're declaring a function with a typedef, typeof, etc as in the 2773 // following example, we'll need to synthesize (unnamed) 2774 // parameters for use in the declaration. 2775 // 2776 // @code 2777 // typedef void fn(int); 2778 // fn f; 2779 // @endcode 2780 2781 // Synthesize a parameter for each argument type. 2782 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2783 AE = FT->arg_type_end(); AI != AE; ++AI) { 2784 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2785 SourceLocation(), 0, 2786 *AI, /*DInfo=*/0, 2787 VarDecl::None, 0); 2788 Param->setImplicit(); 2789 Params.push_back(Param); 2790 } 2791 } else { 2792 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2793 "Should not need args for typedef of non-prototype fn"); 2794 } 2795 // Finally, we know we have the right number of parameters, install them. 2796 NewFD->setParams(Context, Params.data(), Params.size()); 2797 2798 // If name lookup finds a previous declaration that is not in the 2799 // same scope as the new declaration, this may still be an 2800 // acceptable redeclaration. 2801 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2802 !(NewFD->hasLinkage() && 2803 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2804 PrevDecl = 0; 2805 2806 // If the declarator is a template-id, translate the parser's template 2807 // argument list into our AST format. 2808 bool HasExplicitTemplateArgs = false; 2809 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 2810 SourceLocation LAngleLoc, RAngleLoc; 2811 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2812 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2813 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2814 TemplateId->getTemplateArgs(), 2815 TemplateId->getTemplateArgIsType(), 2816 TemplateId->NumArgs); 2817 translateTemplateArguments(TemplateArgsPtr, 2818 TemplateId->getTemplateArgLocations(), 2819 TemplateArgs); 2820 TemplateArgsPtr.release(); 2821 2822 HasExplicitTemplateArgs = true; 2823 LAngleLoc = TemplateId->LAngleLoc; 2824 RAngleLoc = TemplateId->RAngleLoc; 2825 2826 if (FunctionTemplate) { 2827 // FIXME: Diagnose function template with explicit template 2828 // arguments. 2829 HasExplicitTemplateArgs = false; 2830 } else if (!isFunctionTemplateSpecialization && 2831 !D.getDeclSpec().isFriendSpecified()) { 2832 // We have encountered something that the user meant to be a 2833 // specialization (because it has explicitly-specified template 2834 // arguments) but that was not introduced with a "template<>" (or had 2835 // too few of them). 2836 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2837 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2838 << CodeModificationHint::CreateInsertion( 2839 D.getDeclSpec().getSourceRange().getBegin(), 2840 "template<> "); 2841 isFunctionTemplateSpecialization = true; 2842 } 2843 } 2844 2845 if (isFunctionTemplateSpecialization) { 2846 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2847 LAngleLoc, TemplateArgs.data(), 2848 TemplateArgs.size(), RAngleLoc, 2849 PrevDecl)) 2850 NewFD->setInvalidDecl(); 2851 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2852 CheckMemberSpecialization(NewFD, PrevDecl)) 2853 NewFD->setInvalidDecl(); 2854 2855 // Perform semantic checking on the function declaration. 2856 bool OverloadableAttrRequired = false; // FIXME: HACK! 2857 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2858 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2859 2860 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2861 // An out-of-line member function declaration must also be a 2862 // definition (C++ [dcl.meaning]p1). 2863 // Note that this is not the case for explicit specializations of 2864 // function templates or member functions of class templates, per 2865 // C++ [temp.expl.spec]p2. 2866 if (!IsFunctionDefinition && !isFriend && 2867 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2868 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2869 << D.getCXXScopeSpec().getRange(); 2870 NewFD->setInvalidDecl(); 2871 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2872 // The user tried to provide an out-of-line definition for a 2873 // function that is a member of a class or namespace, but there 2874 // was no such member function declared (C++ [class.mfct]p2, 2875 // C++ [namespace.memdef]p2). For example: 2876 // 2877 // class X { 2878 // void f() const; 2879 // }; 2880 // 2881 // void X::f() { } // ill-formed 2882 // 2883 // Complain about this problem, and attempt to suggest close 2884 // matches (e.g., those that differ only in cv-qualifiers and 2885 // whether the parameter types are references). 2886 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2887 << Name << DC << D.getCXXScopeSpec().getRange(); 2888 NewFD->setInvalidDecl(); 2889 2890 LookupResult Prev; 2891 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2892 assert(!Prev.isAmbiguous() && 2893 "Cannot have an ambiguity in previous-declaration lookup"); 2894 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2895 Func != FuncEnd; ++Func) { 2896 if (isa<FunctionDecl>(*Func) && 2897 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2898 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2899 } 2900 2901 PrevDecl = 0; 2902 } 2903 } 2904 2905 // Handle attributes. We need to have merged decls when handling attributes 2906 // (for example to check for conflicts, etc). 2907 // FIXME: This needs to happen before we merge declarations. Then, 2908 // let attribute merging cope with attribute conflicts. 2909 ProcessDeclAttributes(S, NewFD, D); 2910 2911 // attributes declared post-definition are currently ignored 2912 if (Redeclaration && PrevDecl) { 2913 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2914 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2915 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2916 Diag(Def->getLocation(), diag::note_previous_definition); 2917 } 2918 } 2919 2920 AddKnownFunctionAttributes(NewFD); 2921 2922 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2923 // If a function name is overloadable in C, then every function 2924 // with that name must be marked "overloadable". 2925 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2926 << Redeclaration << NewFD; 2927 if (PrevDecl) 2928 Diag(PrevDecl->getLocation(), 2929 diag::note_attribute_overloadable_prev_overload); 2930 NewFD->addAttr(::new (Context) OverloadableAttr()); 2931 } 2932 2933 // If this is a locally-scoped extern C function, update the 2934 // map of such names. 2935 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2936 && !NewFD->isInvalidDecl()) 2937 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2938 2939 // Set this FunctionDecl's range up to the right paren. 2940 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2941 2942 if (FunctionTemplate && NewFD->isInvalidDecl()) 2943 FunctionTemplate->setInvalidDecl(); 2944 2945 if (FunctionTemplate) 2946 return FunctionTemplate; 2947 2948 return NewFD; 2949} 2950 2951/// \brief Perform semantic checking of a new function declaration. 2952/// 2953/// Performs semantic analysis of the new function declaration 2954/// NewFD. This routine performs all semantic checking that does not 2955/// require the actual declarator involved in the declaration, and is 2956/// used both for the declaration of functions as they are parsed 2957/// (called via ActOnDeclarator) and for the declaration of functions 2958/// that have been instantiated via C++ template instantiation (called 2959/// via InstantiateDecl). 2960/// 2961/// \param IsExplicitSpecialiation whether this new function declaration is 2962/// an explicit specialization of the previous declaration. 2963/// 2964/// This sets NewFD->isInvalidDecl() to true if there was an error. 2965void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2966 bool IsExplicitSpecialization, 2967 bool &Redeclaration, 2968 bool &OverloadableAttrRequired) { 2969 // If NewFD is already known erroneous, don't do any of this checking. 2970 if (NewFD->isInvalidDecl()) 2971 return; 2972 2973 if (NewFD->getResultType()->isVariablyModifiedType()) { 2974 // Functions returning a variably modified type violate C99 6.7.5.2p2 2975 // because all functions have linkage. 2976 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2977 return NewFD->setInvalidDecl(); 2978 } 2979 2980 if (NewFD->isMain()) 2981 CheckMain(NewFD); 2982 2983 // Check for a previous declaration of this name. 2984 if (!PrevDecl && NewFD->isExternC()) { 2985 // Since we did not find anything by this name and we're declaring 2986 // an extern "C" function, look for a non-visible extern "C" 2987 // declaration with the same name. 2988 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2989 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2990 if (Pos != LocallyScopedExternalDecls.end()) 2991 PrevDecl = Pos->second; 2992 } 2993 2994 // Merge or overload the declaration with an existing declaration of 2995 // the same name, if appropriate. 2996 if (PrevDecl) { 2997 // Determine whether NewFD is an overload of PrevDecl or 2998 // a declaration that requires merging. If it's an overload, 2999 // there's no more work to do here; we'll just add the new 3000 // function to the scope. 3001 OverloadedFunctionDecl::function_iterator MatchedDecl; 3002 3003 if (!getLangOptions().CPlusPlus && 3004 AllowOverloadingOfFunction(PrevDecl, Context)) { 3005 OverloadableAttrRequired = true; 3006 3007 // Functions marked "overloadable" must have a prototype (that 3008 // we can't get through declaration merging). 3009 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3010 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3011 << NewFD; 3012 Redeclaration = true; 3013 3014 // Turn this into a variadic function with no parameters. 3015 QualType R = Context.getFunctionType( 3016 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3017 0, 0, true, 0); 3018 NewFD->setType(R); 3019 return NewFD->setInvalidDecl(); 3020 } 3021 } 3022 3023 if (PrevDecl && 3024 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3025 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3026 Redeclaration = true; 3027 Decl *OldDecl = PrevDecl; 3028 3029 // If PrevDecl was an overloaded function, extract the 3030 // FunctionDecl that matched. 3031 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3032 OldDecl = *MatchedDecl; 3033 3034 // NewFD and OldDecl represent declarations that need to be 3035 // merged. 3036 if (MergeFunctionDecl(NewFD, OldDecl)) 3037 return NewFD->setInvalidDecl(); 3038 3039 if (FunctionTemplateDecl *OldTemplateDecl 3040 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3041 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3042 FunctionTemplateDecl *NewTemplateDecl 3043 = NewFD->getDescribedFunctionTemplate(); 3044 assert(NewTemplateDecl && "Template/non-template mismatch"); 3045 if (CXXMethodDecl *Method 3046 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3047 Method->setAccess(OldTemplateDecl->getAccess()); 3048 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3049 } 3050 3051 // If this is an explicit specialization of a member that is a function 3052 // template, mark it as a member specialization. 3053 if (IsExplicitSpecialization && 3054 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3055 NewTemplateDecl->setMemberSpecialization(); 3056 assert(OldTemplateDecl->isMemberSpecialization()); 3057 } 3058 } else { 3059 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3060 NewFD->setAccess(OldDecl->getAccess()); 3061 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3062 } 3063 } 3064 } 3065 3066 // Semantic checking for this function declaration (in isolation). 3067 if (getLangOptions().CPlusPlus) { 3068 // C++-specific checks. 3069 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3070 CheckConstructor(Constructor); 3071 } else if (isa<CXXDestructorDecl>(NewFD)) { 3072 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3073 QualType ClassType = Context.getTypeDeclType(Record); 3074 if (!ClassType->isDependentType()) { 3075 DeclarationName Name 3076 = Context.DeclarationNames.getCXXDestructorName( 3077 Context.getCanonicalType(ClassType)); 3078 if (NewFD->getDeclName() != Name) { 3079 Diag(NewFD->getLocation(), diag::err_destructor_name); 3080 return NewFD->setInvalidDecl(); 3081 } 3082 } 3083 Record->setUserDeclaredDestructor(true); 3084 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3085 // user-defined destructor. 3086 Record->setPOD(false); 3087 3088 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3089 // declared destructor. 3090 // FIXME: C++0x: don't do this for "= default" destructors 3091 Record->setHasTrivialDestructor(false); 3092 } else if (CXXConversionDecl *Conversion 3093 = dyn_cast<CXXConversionDecl>(NewFD)) 3094 ActOnConversionDeclarator(Conversion); 3095 3096 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3097 if (NewFD->isOverloadedOperator() && 3098 CheckOverloadedOperatorDeclaration(NewFD)) 3099 return NewFD->setInvalidDecl(); 3100 3101 // In C++, check default arguments now that we have merged decls. Unless 3102 // the lexical context is the class, because in this case this is done 3103 // during delayed parsing anyway. 3104 if (!CurContext->isRecord()) 3105 CheckCXXDefaultArguments(NewFD); 3106 } 3107} 3108 3109void Sema::CheckMain(FunctionDecl* FD) { 3110 // C++ [basic.start.main]p3: A program that declares main to be inline 3111 // or static is ill-formed. 3112 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3113 // shall not appear in a declaration of main. 3114 // static main is not an error under C99, but we should warn about it. 3115 bool isInline = FD->isInlineSpecified(); 3116 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3117 if (isInline || isStatic) { 3118 unsigned diagID = diag::warn_unusual_main_decl; 3119 if (isInline || getLangOptions().CPlusPlus) 3120 diagID = diag::err_unusual_main_decl; 3121 3122 int which = isStatic + (isInline << 1) - 1; 3123 Diag(FD->getLocation(), diagID) << which; 3124 } 3125 3126 QualType T = FD->getType(); 3127 assert(T->isFunctionType() && "function decl is not of function type"); 3128 const FunctionType* FT = T->getAs<FunctionType>(); 3129 3130 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3131 // TODO: add a replacement fixit to turn the return type into 'int'. 3132 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3133 FD->setInvalidDecl(true); 3134 } 3135 3136 // Treat protoless main() as nullary. 3137 if (isa<FunctionNoProtoType>(FT)) return; 3138 3139 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3140 unsigned nparams = FTP->getNumArgs(); 3141 assert(FD->getNumParams() == nparams); 3142 3143 if (nparams > 3) { 3144 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3145 FD->setInvalidDecl(true); 3146 nparams = 3; 3147 } 3148 3149 // FIXME: a lot of the following diagnostics would be improved 3150 // if we had some location information about types. 3151 3152 QualType CharPP = 3153 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3154 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3155 3156 for (unsigned i = 0; i < nparams; ++i) { 3157 QualType AT = FTP->getArgType(i); 3158 3159 bool mismatch = true; 3160 3161 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3162 mismatch = false; 3163 else if (Expected[i] == CharPP) { 3164 // As an extension, the following forms are okay: 3165 // char const ** 3166 // char const * const * 3167 // char * const * 3168 3169 QualifierCollector qs; 3170 const PointerType* PT; 3171 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3172 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3173 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3174 qs.removeConst(); 3175 mismatch = !qs.empty(); 3176 } 3177 } 3178 3179 if (mismatch) { 3180 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3181 // TODO: suggest replacing given type with expected type 3182 FD->setInvalidDecl(true); 3183 } 3184 } 3185 3186 if (nparams == 1 && !FD->isInvalidDecl()) { 3187 Diag(FD->getLocation(), diag::warn_main_one_arg); 3188 } 3189} 3190 3191bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3192 // FIXME: Need strict checking. In C89, we need to check for 3193 // any assignment, increment, decrement, function-calls, or 3194 // commas outside of a sizeof. In C99, it's the same list, 3195 // except that the aforementioned are allowed in unevaluated 3196 // expressions. Everything else falls under the 3197 // "may accept other forms of constant expressions" exception. 3198 // (We never end up here for C++, so the constant expression 3199 // rules there don't matter.) 3200 if (Init->isConstantInitializer(Context)) 3201 return false; 3202 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3203 << Init->getSourceRange(); 3204 return true; 3205} 3206 3207void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3208 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3209} 3210 3211/// AddInitializerToDecl - Adds the initializer Init to the 3212/// declaration dcl. If DirectInit is true, this is C++ direct 3213/// initialization rather than copy initialization. 3214void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3215 Decl *RealDecl = dcl.getAs<Decl>(); 3216 // If there is no declaration, there was an error parsing it. Just ignore 3217 // the initializer. 3218 if (RealDecl == 0) 3219 return; 3220 3221 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3222 // With declarators parsed the way they are, the parser cannot 3223 // distinguish between a normal initializer and a pure-specifier. 3224 // Thus this grotesque test. 3225 IntegerLiteral *IL; 3226 Expr *Init = static_cast<Expr *>(init.get()); 3227 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3228 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3229 if (Method->isVirtualAsWritten()) { 3230 Method->setPure(); 3231 3232 // A class is abstract if at least one function is pure virtual. 3233 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3234 } else if (!Method->isInvalidDecl()) { 3235 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3236 << Method->getDeclName() << Init->getSourceRange(); 3237 Method->setInvalidDecl(); 3238 } 3239 } else { 3240 Diag(Method->getLocation(), diag::err_member_function_initialization) 3241 << Method->getDeclName() << Init->getSourceRange(); 3242 Method->setInvalidDecl(); 3243 } 3244 return; 3245 } 3246 3247 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3248 if (!VDecl) { 3249 if (getLangOptions().CPlusPlus && 3250 RealDecl->getLexicalDeclContext()->isRecord() && 3251 isa<NamedDecl>(RealDecl)) 3252 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3253 << cast<NamedDecl>(RealDecl)->getDeclName(); 3254 else 3255 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3256 RealDecl->setInvalidDecl(); 3257 return; 3258 } 3259 3260 if (!VDecl->getType()->isArrayType() && 3261 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3262 diag::err_typecheck_decl_incomplete_type)) { 3263 RealDecl->setInvalidDecl(); 3264 return; 3265 } 3266 3267 const VarDecl *Def = 0; 3268 if (VDecl->getDefinition(Def)) { 3269 Diag(VDecl->getLocation(), diag::err_redefinition) 3270 << VDecl->getDeclName(); 3271 Diag(Def->getLocation(), diag::note_previous_definition); 3272 VDecl->setInvalidDecl(); 3273 return; 3274 } 3275 3276 // Take ownership of the expression, now that we're sure we have somewhere 3277 // to put it. 3278 Expr *Init = init.takeAs<Expr>(); 3279 assert(Init && "missing initializer"); 3280 3281 // Get the decls type and save a reference for later, since 3282 // CheckInitializerTypes may change it. 3283 QualType DclT = VDecl->getType(), SavT = DclT; 3284 if (VDecl->isBlockVarDecl()) { 3285 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3286 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3287 VDecl->setInvalidDecl(); 3288 } else if (!VDecl->isInvalidDecl()) { 3289 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3290 VDecl->getDeclName(), DirectInit)) 3291 VDecl->setInvalidDecl(); 3292 3293 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3294 // Don't check invalid declarations to avoid emitting useless diagnostics. 3295 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3296 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3297 CheckForConstantInitializer(Init, DclT); 3298 } 3299 } 3300 } else if (VDecl->isStaticDataMember() && 3301 VDecl->getLexicalDeclContext()->isRecord()) { 3302 // This is an in-class initialization for a static data member, e.g., 3303 // 3304 // struct S { 3305 // static const int value = 17; 3306 // }; 3307 3308 // Attach the initializer 3309 VDecl->setInit(Context, Init); 3310 3311 // C++ [class.mem]p4: 3312 // A member-declarator can contain a constant-initializer only 3313 // if it declares a static member (9.4) of const integral or 3314 // const enumeration type, see 9.4.2. 3315 QualType T = VDecl->getType(); 3316 if (!T->isDependentType() && 3317 (!Context.getCanonicalType(T).isConstQualified() || 3318 !T->isIntegralType())) { 3319 Diag(VDecl->getLocation(), diag::err_member_initialization) 3320 << VDecl->getDeclName() << Init->getSourceRange(); 3321 VDecl->setInvalidDecl(); 3322 } else { 3323 // C++ [class.static.data]p4: 3324 // If a static data member is of const integral or const 3325 // enumeration type, its declaration in the class definition 3326 // can specify a constant-initializer which shall be an 3327 // integral constant expression (5.19). 3328 if (!Init->isTypeDependent() && 3329 !Init->getType()->isIntegralType()) { 3330 // We have a non-dependent, non-integral or enumeration type. 3331 Diag(Init->getSourceRange().getBegin(), 3332 diag::err_in_class_initializer_non_integral_type) 3333 << Init->getType() << Init->getSourceRange(); 3334 VDecl->setInvalidDecl(); 3335 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3336 // Check whether the expression is a constant expression. 3337 llvm::APSInt Value; 3338 SourceLocation Loc; 3339 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3340 Diag(Loc, diag::err_in_class_initializer_non_constant) 3341 << Init->getSourceRange(); 3342 VDecl->setInvalidDecl(); 3343 } else if (!VDecl->getType()->isDependentType()) 3344 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3345 } 3346 } 3347 } else if (VDecl->isFileVarDecl()) { 3348 if (VDecl->getStorageClass() == VarDecl::Extern) 3349 Diag(VDecl->getLocation(), diag::warn_extern_init); 3350 if (!VDecl->isInvalidDecl()) 3351 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3352 VDecl->getDeclName(), DirectInit)) 3353 VDecl->setInvalidDecl(); 3354 3355 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3356 // Don't check invalid declarations to avoid emitting useless diagnostics. 3357 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3358 // C99 6.7.8p4. All file scoped initializers need to be constant. 3359 CheckForConstantInitializer(Init, DclT); 3360 } 3361 } 3362 // If the type changed, it means we had an incomplete type that was 3363 // completed by the initializer. For example: 3364 // int ary[] = { 1, 3, 5 }; 3365 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3366 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3367 VDecl->setType(DclT); 3368 Init->setType(DclT); 3369 } 3370 3371 Init = MaybeCreateCXXExprWithTemporaries(Init, 3372 /*ShouldDestroyTemporaries=*/true); 3373 // Attach the initializer to the decl. 3374 VDecl->setInit(Context, Init); 3375 3376 // If the previous declaration of VDecl was a tentative definition, 3377 // remove it from the set of tentative definitions. 3378 if (VDecl->getPreviousDeclaration() && 3379 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3380 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3381 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3382 } 3383 3384 return; 3385} 3386 3387void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3388 bool TypeContainsUndeducedAuto) { 3389 Decl *RealDecl = dcl.getAs<Decl>(); 3390 3391 // If there is no declaration, there was an error parsing it. Just ignore it. 3392 if (RealDecl == 0) 3393 return; 3394 3395 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3396 QualType Type = Var->getType(); 3397 3398 // Record tentative definitions. 3399 if (Var->isTentativeDefinition(Context)) { 3400 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3401 InsertPair = 3402 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3403 3404 // Keep the latest definition in the map. If we see 'int i; int i;' we 3405 // want the second one in the map. 3406 InsertPair.first->second = Var; 3407 3408 // However, for the list, we don't care about the order, just make sure 3409 // that there are no dupes for a given declaration name. 3410 if (InsertPair.second) 3411 TentativeDefinitionList.push_back(Var->getDeclName()); 3412 } 3413 3414 // C++ [dcl.init.ref]p3: 3415 // The initializer can be omitted for a reference only in a 3416 // parameter declaration (8.3.5), in the declaration of a 3417 // function return type, in the declaration of a class member 3418 // within its class declaration (9.2), and where the extern 3419 // specifier is explicitly used. 3420 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3421 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3422 << Var->getDeclName() 3423 << SourceRange(Var->getLocation(), Var->getLocation()); 3424 Var->setInvalidDecl(); 3425 return; 3426 } 3427 3428 // C++0x [dcl.spec.auto]p3 3429 if (TypeContainsUndeducedAuto) { 3430 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3431 << Var->getDeclName() << Type; 3432 Var->setInvalidDecl(); 3433 return; 3434 } 3435 3436 // An array without size is an incomplete type, and there are no special 3437 // rules in C++ to make such a definition acceptable. 3438 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3439 !Var->hasExternalStorage()) { 3440 Diag(Var->getLocation(), 3441 diag::err_typecheck_incomplete_array_needs_initializer); 3442 Var->setInvalidDecl(); 3443 return; 3444 } 3445 3446 // C++ [temp.expl.spec]p15: 3447 // An explicit specialization of a static data member of a template is a 3448 // definition if the declaration includes an initializer; otherwise, it 3449 // is a declaration. 3450 if (Var->isStaticDataMember() && 3451 Var->getInstantiatedFromStaticDataMember() && 3452 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3453 return; 3454 3455 // C++ [dcl.init]p9: 3456 // If no initializer is specified for an object, and the object 3457 // is of (possibly cv-qualified) non-POD class type (or array 3458 // thereof), the object shall be default-initialized; if the 3459 // object is of const-qualified type, the underlying class type 3460 // shall have a user-declared default constructor. 3461 // 3462 // FIXME: Diagnose the "user-declared default constructor" bit. 3463 if (getLangOptions().CPlusPlus) { 3464 QualType InitType = Type; 3465 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3466 InitType = Context.getBaseElementType(Array); 3467 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3468 InitType->isRecordType() && !InitType->isDependentType()) { 3469 if (!RequireCompleteType(Var->getLocation(), InitType, 3470 diag::err_invalid_incomplete_type_use)) { 3471 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3472 3473 CXXConstructorDecl *Constructor 3474 = PerformInitializationByConstructor(InitType, 3475 MultiExprArg(*this, 0, 0), 3476 Var->getLocation(), 3477 SourceRange(Var->getLocation(), 3478 Var->getLocation()), 3479 Var->getDeclName(), 3480 IK_Default, 3481 ConstructorArgs); 3482 3483 // FIXME: Location info for the variable initialization? 3484 if (!Constructor) 3485 Var->setInvalidDecl(); 3486 else { 3487 // FIXME: Cope with initialization of arrays 3488 if (!Constructor->isTrivial() && 3489 InitializeVarWithConstructor(Var, Constructor, 3490 move_arg(ConstructorArgs))) 3491 Var->setInvalidDecl(); 3492 3493 FinalizeVarWithDestructor(Var, InitType); 3494 } 3495 } else { 3496 Var->setInvalidDecl(); 3497 } 3498 } 3499 } 3500 3501#if 0 3502 // FIXME: Temporarily disabled because we are not properly parsing 3503 // linkage specifications on declarations, e.g., 3504 // 3505 // extern "C" const CGPoint CGPointerZero; 3506 // 3507 // C++ [dcl.init]p9: 3508 // 3509 // If no initializer is specified for an object, and the 3510 // object is of (possibly cv-qualified) non-POD class type (or 3511 // array thereof), the object shall be default-initialized; if 3512 // the object is of const-qualified type, the underlying class 3513 // type shall have a user-declared default 3514 // constructor. Otherwise, if no initializer is specified for 3515 // an object, the object and its subobjects, if any, have an 3516 // indeterminate initial value; if the object or any of its 3517 // subobjects are of const-qualified type, the program is 3518 // ill-formed. 3519 // 3520 // This isn't technically an error in C, so we don't diagnose it. 3521 // 3522 // FIXME: Actually perform the POD/user-defined default 3523 // constructor check. 3524 if (getLangOptions().CPlusPlus && 3525 Context.getCanonicalType(Type).isConstQualified() && 3526 !Var->hasExternalStorage()) 3527 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3528 << Var->getName() 3529 << SourceRange(Var->getLocation(), Var->getLocation()); 3530#endif 3531 } 3532} 3533 3534Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3535 DeclPtrTy *Group, 3536 unsigned NumDecls) { 3537 llvm::SmallVector<Decl*, 8> Decls; 3538 3539 if (DS.isTypeSpecOwned()) 3540 Decls.push_back((Decl*)DS.getTypeRep()); 3541 3542 for (unsigned i = 0; i != NumDecls; ++i) 3543 if (Decl *D = Group[i].getAs<Decl>()) 3544 Decls.push_back(D); 3545 3546 // Perform semantic analysis that depends on having fully processed both 3547 // the declarator and initializer. 3548 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3549 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3550 if (!IDecl) 3551 continue; 3552 QualType T = IDecl->getType(); 3553 3554 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3555 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3556 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3557 if (T->isDependentType()) { 3558 // If T is dependent, we should not require a complete type. 3559 // (RequireCompleteType shouldn't be called with dependent types.) 3560 // But we still can at least check if we've got an array of unspecified 3561 // size without an initializer. 3562 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3563 !IDecl->getInit()) { 3564 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3565 << T; 3566 IDecl->setInvalidDecl(); 3567 } 3568 } else if (!IDecl->isInvalidDecl()) { 3569 // If T is an incomplete array type with an initializer list that is 3570 // dependent on something, its size has not been fixed. We could attempt 3571 // to fix the size for such arrays, but we would still have to check 3572 // here for initializers containing a C++0x vararg expansion, e.g. 3573 // template <typename... Args> void f(Args... args) { 3574 // int vals[] = { args }; 3575 // } 3576 const IncompleteArrayType *IAT = T->getAs<IncompleteArrayType>(); 3577 Expr *Init = IDecl->getInit(); 3578 if (IAT && Init && 3579 (Init->isTypeDependent() || Init->isValueDependent())) { 3580 // Check that the member type of the array is complete, at least. 3581 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3582 diag::err_typecheck_decl_incomplete_type)) 3583 IDecl->setInvalidDecl(); 3584 } else if (RequireCompleteType(IDecl->getLocation(), T, 3585 diag::err_typecheck_decl_incomplete_type)) 3586 IDecl->setInvalidDecl(); 3587 } 3588 } 3589 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3590 // object that has file scope without an initializer, and without a 3591 // storage-class specifier or with the storage-class specifier "static", 3592 // constitutes a tentative definition. Note: A tentative definition with 3593 // external linkage is valid (C99 6.2.2p5). 3594 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3595 if (const IncompleteArrayType *ArrayT 3596 = Context.getAsIncompleteArrayType(T)) { 3597 if (RequireCompleteType(IDecl->getLocation(), 3598 ArrayT->getElementType(), 3599 diag::err_illegal_decl_array_incomplete_type)) 3600 IDecl->setInvalidDecl(); 3601 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3602 // C99 6.9.2p3: If the declaration of an identifier for an object is 3603 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3604 // declared type shall not be an incomplete type. 3605 // NOTE: code such as the following 3606 // static struct s; 3607 // struct s { int a; }; 3608 // is accepted by gcc. Hence here we issue a warning instead of 3609 // an error and we do not invalidate the static declaration. 3610 // NOTE: to avoid multiple warnings, only check the first declaration. 3611 if (IDecl->getPreviousDeclaration() == 0) 3612 RequireCompleteType(IDecl->getLocation(), T, 3613 diag::ext_typecheck_decl_incomplete_type); 3614 } 3615 } 3616 } 3617 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3618 Decls.data(), Decls.size())); 3619} 3620 3621 3622/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3623/// to introduce parameters into function prototype scope. 3624Sema::DeclPtrTy 3625Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3626 const DeclSpec &DS = D.getDeclSpec(); 3627 3628 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3629 VarDecl::StorageClass StorageClass = VarDecl::None; 3630 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3631 StorageClass = VarDecl::Register; 3632 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3633 Diag(DS.getStorageClassSpecLoc(), 3634 diag::err_invalid_storage_class_in_func_decl); 3635 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3636 } 3637 3638 if (D.getDeclSpec().isThreadSpecified()) 3639 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3640 3641 DiagnoseFunctionSpecifiers(D); 3642 3643 // Check that there are no default arguments inside the type of this 3644 // parameter (C++ only). 3645 if (getLangOptions().CPlusPlus) 3646 CheckExtraCXXDefaultArguments(D); 3647 3648 DeclaratorInfo *DInfo = 0; 3649 TagDecl *OwnedDecl = 0; 3650 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3651 3652 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3653 // C++ [dcl.fct]p6: 3654 // Types shall not be defined in return or parameter types. 3655 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3656 << Context.getTypeDeclType(OwnedDecl); 3657 } 3658 3659 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3660 // Can this happen for params? We already checked that they don't conflict 3661 // among each other. Here they can only shadow globals, which is ok. 3662 IdentifierInfo *II = D.getIdentifier(); 3663 if (II) { 3664 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3665 if (PrevDecl->isTemplateParameter()) { 3666 // Maybe we will complain about the shadowed template parameter. 3667 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3668 // Just pretend that we didn't see the previous declaration. 3669 PrevDecl = 0; 3670 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3671 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3672 3673 // Recover by removing the name 3674 II = 0; 3675 D.SetIdentifier(0, D.getIdentifierLoc()); 3676 } 3677 } 3678 } 3679 3680 // Parameters can not be abstract class types. 3681 // For record types, this is done by the AbstractClassUsageDiagnoser once 3682 // the class has been completely parsed. 3683 if (!CurContext->isRecord() && 3684 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3685 diag::err_abstract_type_in_decl, 3686 AbstractParamType)) 3687 D.setInvalidType(true); 3688 3689 QualType T = adjustParameterType(parmDeclType); 3690 3691 ParmVarDecl *New 3692 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3693 T, DInfo, StorageClass, 0); 3694 3695 if (D.isInvalidType()) 3696 New->setInvalidDecl(); 3697 3698 // Parameter declarators cannot be interface types. All ObjC objects are 3699 // passed by reference. 3700 if (T->isObjCInterfaceType()) { 3701 Diag(D.getIdentifierLoc(), 3702 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3703 New->setInvalidDecl(); 3704 } 3705 3706 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3707 if (D.getCXXScopeSpec().isSet()) { 3708 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3709 << D.getCXXScopeSpec().getRange(); 3710 New->setInvalidDecl(); 3711 } 3712 3713 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3714 // duration shall not be qualified by an address-space qualifier." 3715 // Since all parameters have automatic store duration, they can not have 3716 // an address space. 3717 if (T.getAddressSpace() != 0) { 3718 Diag(D.getIdentifierLoc(), 3719 diag::err_arg_with_address_space); 3720 New->setInvalidDecl(); 3721 } 3722 3723 3724 // Add the parameter declaration into this scope. 3725 S->AddDecl(DeclPtrTy::make(New)); 3726 if (II) 3727 IdResolver.AddDecl(New); 3728 3729 ProcessDeclAttributes(S, New, D); 3730 3731 if (New->hasAttr<BlocksAttr>()) { 3732 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3733 } 3734 return DeclPtrTy::make(New); 3735} 3736 3737void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3738 SourceLocation LocAfterDecls) { 3739 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3740 "Not a function declarator!"); 3741 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3742 3743 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3744 // for a K&R function. 3745 if (!FTI.hasPrototype) { 3746 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3747 --i; 3748 if (FTI.ArgInfo[i].Param == 0) { 3749 llvm::SmallString<256> Code; 3750 llvm::raw_svector_ostream(Code) << " int " 3751 << FTI.ArgInfo[i].Ident->getName() 3752 << ";\n"; 3753 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3754 << FTI.ArgInfo[i].Ident 3755 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3756 3757 // Implicitly declare the argument as type 'int' for lack of a better 3758 // type. 3759 DeclSpec DS; 3760 const char* PrevSpec; // unused 3761 unsigned DiagID; // unused 3762 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3763 PrevSpec, DiagID); 3764 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3765 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3766 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3767 } 3768 } 3769 } 3770} 3771 3772Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3773 Declarator &D) { 3774 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3775 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3776 "Not a function declarator!"); 3777 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3778 3779 if (FTI.hasPrototype) { 3780 // FIXME: Diagnose arguments without names in C. 3781 } 3782 3783 Scope *ParentScope = FnBodyScope->getParent(); 3784 3785 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3786 MultiTemplateParamsArg(*this), 3787 /*IsFunctionDefinition=*/true); 3788 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3789} 3790 3791Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3792 // Clear the last template instantiation error context. 3793 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 3794 3795 if (!D) 3796 return D; 3797 FunctionDecl *FD = 0; 3798 3799 if (FunctionTemplateDecl *FunTmpl 3800 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3801 FD = FunTmpl->getTemplatedDecl(); 3802 else 3803 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3804 3805 CurFunctionNeedsScopeChecking = false; 3806 3807 // See if this is a redefinition. 3808 const FunctionDecl *Definition; 3809 if (FD->getBody(Definition)) { 3810 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3811 Diag(Definition->getLocation(), diag::note_previous_definition); 3812 } 3813 3814 // Builtin functions cannot be defined. 3815 if (unsigned BuiltinID = FD->getBuiltinID()) { 3816 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3817 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3818 FD->setInvalidDecl(); 3819 } 3820 } 3821 3822 // The return type of a function definition must be complete 3823 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3824 QualType ResultType = FD->getResultType(); 3825 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3826 !FD->isInvalidDecl() && 3827 RequireCompleteType(FD->getLocation(), ResultType, 3828 diag::err_func_def_incomplete_result)) 3829 FD->setInvalidDecl(); 3830 3831 // GNU warning -Wmissing-prototypes: 3832 // Warn if a global function is defined without a previous 3833 // prototype declaration. This warning is issued even if the 3834 // definition itself provides a prototype. The aim is to detect 3835 // global functions that fail to be declared in header files. 3836 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3837 !FD->isMain()) { 3838 bool MissingPrototype = true; 3839 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3840 Prev; Prev = Prev->getPreviousDeclaration()) { 3841 // Ignore any declarations that occur in function or method 3842 // scope, because they aren't visible from the header. 3843 if (Prev->getDeclContext()->isFunctionOrMethod()) 3844 continue; 3845 3846 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3847 break; 3848 } 3849 3850 if (MissingPrototype) 3851 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3852 } 3853 3854 if (FnBodyScope) 3855 PushDeclContext(FnBodyScope, FD); 3856 3857 // Check the validity of our function parameters 3858 CheckParmsForFunctionDef(FD); 3859 3860 // Introduce our parameters into the function scope 3861 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3862 ParmVarDecl *Param = FD->getParamDecl(p); 3863 Param->setOwningFunction(FD); 3864 3865 // If this has an identifier, add it to the scope stack. 3866 if (Param->getIdentifier() && FnBodyScope) 3867 PushOnScopeChains(Param, FnBodyScope); 3868 } 3869 3870 // Checking attributes of current function definition 3871 // dllimport attribute. 3872 if (FD->getAttr<DLLImportAttr>() && 3873 (!FD->getAttr<DLLExportAttr>())) { 3874 // dllimport attribute cannot be applied to definition. 3875 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3876 Diag(FD->getLocation(), 3877 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3878 << "dllimport"; 3879 FD->setInvalidDecl(); 3880 return DeclPtrTy::make(FD); 3881 } else { 3882 // If a symbol previously declared dllimport is later defined, the 3883 // attribute is ignored in subsequent references, and a warning is 3884 // emitted. 3885 Diag(FD->getLocation(), 3886 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3887 << FD->getNameAsCString() << "dllimport"; 3888 } 3889 } 3890 return DeclPtrTy::make(FD); 3891} 3892 3893Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3894 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3895} 3896 3897Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3898 bool IsInstantiation) { 3899 Decl *dcl = D.getAs<Decl>(); 3900 Stmt *Body = BodyArg.takeAs<Stmt>(); 3901 3902 FunctionDecl *FD = 0; 3903 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3904 if (FunTmpl) 3905 FD = FunTmpl->getTemplatedDecl(); 3906 else 3907 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3908 3909 if (FD) { 3910 FD->setBody(Body); 3911 if (FD->isMain()) 3912 // C and C++ allow for main to automagically return 0. 3913 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3914 FD->setHasImplicitReturnZero(true); 3915 else 3916 CheckFallThroughForFunctionDef(FD, Body); 3917 3918 if (!FD->isInvalidDecl()) 3919 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3920 3921 // C++ [basic.def.odr]p2: 3922 // [...] A virtual member function is used if it is not pure. [...] 3923 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3924 if (Method->isVirtual() && !Method->isPure()) 3925 MarkDeclarationReferenced(Method->getLocation(), Method); 3926 3927 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3928 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3929 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3930 MD->setBody(Body); 3931 CheckFallThroughForFunctionDef(MD, Body); 3932 MD->setEndLoc(Body->getLocEnd()); 3933 3934 if (!MD->isInvalidDecl()) 3935 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3936 } else { 3937 Body->Destroy(Context); 3938 return DeclPtrTy(); 3939 } 3940 if (!IsInstantiation) 3941 PopDeclContext(); 3942 3943 // Verify and clean out per-function state. 3944 3945 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3946 3947 // Check goto/label use. 3948 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3949 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3950 LabelStmt *L = I->second; 3951 3952 // Verify that we have no forward references left. If so, there was a goto 3953 // or address of a label taken, but no definition of it. Label fwd 3954 // definitions are indicated with a null substmt. 3955 if (L->getSubStmt() != 0) 3956 continue; 3957 3958 // Emit error. 3959 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3960 3961 // At this point, we have gotos that use the bogus label. Stitch it into 3962 // the function body so that they aren't leaked and that the AST is well 3963 // formed. 3964 if (Body == 0) { 3965 // The whole function wasn't parsed correctly, just delete this. 3966 L->Destroy(Context); 3967 continue; 3968 } 3969 3970 // Otherwise, the body is valid: we want to stitch the label decl into the 3971 // function somewhere so that it is properly owned and so that the goto 3972 // has a valid target. Do this by creating a new compound stmt with the 3973 // label in it. 3974 3975 // Give the label a sub-statement. 3976 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3977 3978 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3979 cast<CXXTryStmt>(Body)->getTryBlock() : 3980 cast<CompoundStmt>(Body); 3981 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3982 Elements.push_back(L); 3983 Compound->setStmts(Context, &Elements[0], Elements.size()); 3984 } 3985 FunctionLabelMap.clear(); 3986 3987 if (!Body) return D; 3988 3989 // Verify that that gotos and switch cases don't jump into scopes illegally. 3990 if (CurFunctionNeedsScopeChecking) 3991 DiagnoseInvalidJumps(Body); 3992 3993 // C++ constructors that have function-try-blocks can't have return 3994 // statements in the handlers of that block. (C++ [except.handle]p14) 3995 // Verify this. 3996 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3997 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3998 3999 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4000 computeBaseOrMembersToDestroy(Destructor); 4001 return D; 4002} 4003 4004/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4005/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4006NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4007 IdentifierInfo &II, Scope *S) { 4008 // Before we produce a declaration for an implicitly defined 4009 // function, see whether there was a locally-scoped declaration of 4010 // this name as a function or variable. If so, use that 4011 // (non-visible) declaration, and complain about it. 4012 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4013 = LocallyScopedExternalDecls.find(&II); 4014 if (Pos != LocallyScopedExternalDecls.end()) { 4015 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4016 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4017 return Pos->second; 4018 } 4019 4020 // Extension in C99. Legal in C90, but warn about it. 4021 if (II.getName().startswith("__builtin_")) 4022 Diag(Loc, diag::warn_builtin_unknown) << &II; 4023 else if (getLangOptions().C99) 4024 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4025 else 4026 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4027 4028 // Set a Declarator for the implicit definition: int foo(); 4029 const char *Dummy; 4030 DeclSpec DS; 4031 unsigned DiagID; 4032 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4033 Error = Error; // Silence warning. 4034 assert(!Error && "Error setting up implicit decl!"); 4035 Declarator D(DS, Declarator::BlockContext); 4036 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4037 0, 0, false, SourceLocation(), 4038 false, 0,0,0, Loc, Loc, D), 4039 SourceLocation()); 4040 D.SetIdentifier(&II, Loc); 4041 4042 // Insert this function into translation-unit scope. 4043 4044 DeclContext *PrevDC = CurContext; 4045 CurContext = Context.getTranslationUnitDecl(); 4046 4047 FunctionDecl *FD = 4048 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4049 FD->setImplicit(); 4050 4051 CurContext = PrevDC; 4052 4053 AddKnownFunctionAttributes(FD); 4054 4055 return FD; 4056} 4057 4058/// \brief Adds any function attributes that we know a priori based on 4059/// the declaration of this function. 4060/// 4061/// These attributes can apply both to implicitly-declared builtins 4062/// (like __builtin___printf_chk) or to library-declared functions 4063/// like NSLog or printf. 4064void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4065 if (FD->isInvalidDecl()) 4066 return; 4067 4068 // If this is a built-in function, map its builtin attributes to 4069 // actual attributes. 4070 if (unsigned BuiltinID = FD->getBuiltinID()) { 4071 // Handle printf-formatting attributes. 4072 unsigned FormatIdx; 4073 bool HasVAListArg; 4074 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4075 if (!FD->getAttr<FormatAttr>()) 4076 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4077 HasVAListArg ? 0 : FormatIdx + 2)); 4078 } 4079 4080 // Mark const if we don't care about errno and that is the only 4081 // thing preventing the function from being const. This allows 4082 // IRgen to use LLVM intrinsics for such functions. 4083 if (!getLangOptions().MathErrno && 4084 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4085 if (!FD->getAttr<ConstAttr>()) 4086 FD->addAttr(::new (Context) ConstAttr()); 4087 } 4088 4089 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4090 FD->addAttr(::new (Context) NoReturnAttr()); 4091 } 4092 4093 IdentifierInfo *Name = FD->getIdentifier(); 4094 if (!Name) 4095 return; 4096 if ((!getLangOptions().CPlusPlus && 4097 FD->getDeclContext()->isTranslationUnit()) || 4098 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4099 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4100 LinkageSpecDecl::lang_c)) { 4101 // Okay: this could be a libc/libm/Objective-C function we know 4102 // about. 4103 } else 4104 return; 4105 4106 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4107 // FIXME: NSLog and NSLogv should be target specific 4108 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4109 // FIXME: We known better than our headers. 4110 const_cast<FormatAttr *>(Format)->setType("printf"); 4111 } else 4112 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4113 Name->isStr("NSLogv") ? 0 : 2)); 4114 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4115 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4116 // target-specific builtins, perhaps? 4117 if (!FD->getAttr<FormatAttr>()) 4118 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4119 Name->isStr("vasprintf") ? 0 : 3)); 4120 } 4121} 4122 4123TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4124 DeclaratorInfo *DInfo) { 4125 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4126 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4127 4128 if (!DInfo) { 4129 assert(D.isInvalidType() && "no declarator info for valid type"); 4130 DInfo = Context.getTrivialDeclaratorInfo(T); 4131 } 4132 4133 // Scope manipulation handled by caller. 4134 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4135 D.getIdentifierLoc(), 4136 D.getIdentifier(), 4137 DInfo); 4138 4139 if (const TagType *TT = T->getAs<TagType>()) { 4140 TagDecl *TD = TT->getDecl(); 4141 4142 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4143 // keep track of the TypedefDecl. 4144 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4145 TD->setTypedefForAnonDecl(NewTD); 4146 } 4147 4148 if (D.isInvalidType()) 4149 NewTD->setInvalidDecl(); 4150 return NewTD; 4151} 4152 4153 4154/// \brief Determine whether a tag with a given kind is acceptable 4155/// as a redeclaration of the given tag declaration. 4156/// 4157/// \returns true if the new tag kind is acceptable, false otherwise. 4158bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4159 TagDecl::TagKind NewTag, 4160 SourceLocation NewTagLoc, 4161 const IdentifierInfo &Name) { 4162 // C++ [dcl.type.elab]p3: 4163 // The class-key or enum keyword present in the 4164 // elaborated-type-specifier shall agree in kind with the 4165 // declaration to which the name in theelaborated-type-specifier 4166 // refers. This rule also applies to the form of 4167 // elaborated-type-specifier that declares a class-name or 4168 // friend class since it can be construed as referring to the 4169 // definition of the class. Thus, in any 4170 // elaborated-type-specifier, the enum keyword shall be used to 4171 // refer to an enumeration (7.2), the union class-keyshall be 4172 // used to refer to a union (clause 9), and either the class or 4173 // struct class-key shall be used to refer to a class (clause 9) 4174 // declared using the class or struct class-key. 4175 TagDecl::TagKind OldTag = Previous->getTagKind(); 4176 if (OldTag == NewTag) 4177 return true; 4178 4179 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4180 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4181 // Warn about the struct/class tag mismatch. 4182 bool isTemplate = false; 4183 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4184 isTemplate = Record->getDescribedClassTemplate(); 4185 4186 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4187 << (NewTag == TagDecl::TK_class) 4188 << isTemplate << &Name 4189 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4190 OldTag == TagDecl::TK_class? "class" : "struct"); 4191 Diag(Previous->getLocation(), diag::note_previous_use); 4192 return true; 4193 } 4194 return false; 4195} 4196 4197/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4198/// former case, Name will be non-null. In the later case, Name will be null. 4199/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4200/// reference/declaration/definition of a tag. 4201Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4202 SourceLocation KWLoc, const CXXScopeSpec &SS, 4203 IdentifierInfo *Name, SourceLocation NameLoc, 4204 AttributeList *Attr, AccessSpecifier AS, 4205 MultiTemplateParamsArg TemplateParameterLists, 4206 bool &OwnedDecl, bool &IsDependent) { 4207 // If this is not a definition, it must have a name. 4208 assert((Name != 0 || TUK == TUK_Definition) && 4209 "Nameless record must be a definition!"); 4210 4211 OwnedDecl = false; 4212 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4213 4214 // FIXME: Check explicit specializations more carefully. 4215 bool isExplicitSpecialization = false; 4216 if (TUK != TUK_Reference) { 4217 if (TemplateParameterList *TemplateParams 4218 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4219 (TemplateParameterList**)TemplateParameterLists.get(), 4220 TemplateParameterLists.size(), 4221 isExplicitSpecialization)) { 4222 if (TemplateParams->size() > 0) { 4223 // This is a declaration or definition of a class template (which may 4224 // be a member of another template). 4225 OwnedDecl = false; 4226 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4227 SS, Name, NameLoc, Attr, 4228 TemplateParams, 4229 AS); 4230 TemplateParameterLists.release(); 4231 return Result.get(); 4232 } else { 4233 // The "template<>" header is extraneous. 4234 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4235 << ElaboratedType::getNameForTagKind(Kind) << Name; 4236 isExplicitSpecialization = true; 4237 } 4238 } 4239 4240 TemplateParameterLists.release(); 4241 } 4242 4243 DeclContext *SearchDC = CurContext; 4244 DeclContext *DC = CurContext; 4245 NamedDecl *PrevDecl = 0; 4246 bool isStdBadAlloc = false; 4247 bool Invalid = false; 4248 4249 bool RedeclarationOnly = (TUK != TUK_Reference); 4250 4251 if (Name && SS.isNotEmpty()) { 4252 // We have a nested-name tag ('struct foo::bar'). 4253 4254 // Check for invalid 'foo::'. 4255 if (SS.isInvalid()) { 4256 Name = 0; 4257 goto CreateNewDecl; 4258 } 4259 4260 // If this is a friend or a reference to a class in a dependent 4261 // context, don't try to make a decl for it. 4262 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4263 DC = computeDeclContext(SS, false); 4264 if (!DC) { 4265 IsDependent = true; 4266 return DeclPtrTy(); 4267 } 4268 } 4269 4270 if (RequireCompleteDeclContext(SS)) 4271 return DeclPtrTy::make((Decl *)0); 4272 4273 DC = computeDeclContext(SS, true); 4274 SearchDC = DC; 4275 // Look-up name inside 'foo::'. 4276 LookupResult R; 4277 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4278 4279 if (R.isAmbiguous()) { 4280 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4281 return DeclPtrTy(); 4282 } 4283 4284 if (R.getKind() == LookupResult::Found) 4285 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4286 4287 // A tag 'foo::bar' must already exist. 4288 if (!PrevDecl) { 4289 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4290 Name = 0; 4291 Invalid = true; 4292 goto CreateNewDecl; 4293 } 4294 } else if (Name) { 4295 // If this is a named struct, check to see if there was a previous forward 4296 // declaration or definition. 4297 // FIXME: We're looking into outer scopes here, even when we 4298 // shouldn't be. Doing so can result in ambiguities that we 4299 // shouldn't be diagnosing. 4300 LookupResult R; 4301 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4302 if (R.isAmbiguous()) { 4303 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4304 // FIXME: This is not best way to recover from case like: 4305 // 4306 // struct S s; 4307 // 4308 // causes needless "incomplete type" error later. 4309 Name = 0; 4310 PrevDecl = 0; 4311 Invalid = true; 4312 } else 4313 PrevDecl = R.getAsSingleDecl(Context); 4314 4315 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4316 // FIXME: This makes sure that we ignore the contexts associated 4317 // with C structs, unions, and enums when looking for a matching 4318 // tag declaration or definition. See the similar lookup tweak 4319 // in Sema::LookupName; is there a better way to deal with this? 4320 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4321 SearchDC = SearchDC->getParent(); 4322 } 4323 } 4324 4325 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4326 // Maybe we will complain about the shadowed template parameter. 4327 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4328 // Just pretend that we didn't see the previous declaration. 4329 PrevDecl = 0; 4330 } 4331 4332 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4333 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4334 // This is a declaration of or a reference to "std::bad_alloc". 4335 isStdBadAlloc = true; 4336 4337 if (!PrevDecl && StdBadAlloc) { 4338 // std::bad_alloc has been implicitly declared (but made invisible to 4339 // name lookup). Fill in this implicit declaration as the previous 4340 // declaration, so that the declarations get chained appropriately. 4341 PrevDecl = StdBadAlloc; 4342 } 4343 } 4344 4345 if (PrevDecl) { 4346 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4347 // If this is a use of a previous tag, or if the tag is already declared 4348 // in the same scope (so that the definition/declaration completes or 4349 // rementions the tag), reuse the decl. 4350 if (TUK == TUK_Reference || TUK == TUK_Friend || 4351 isDeclInScope(PrevDecl, SearchDC, S)) { 4352 // Make sure that this wasn't declared as an enum and now used as a 4353 // struct or something similar. 4354 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4355 bool SafeToContinue 4356 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4357 Kind != TagDecl::TK_enum); 4358 if (SafeToContinue) 4359 Diag(KWLoc, diag::err_use_with_wrong_tag) 4360 << Name 4361 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4362 PrevTagDecl->getKindName()); 4363 else 4364 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4365 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4366 4367 if (SafeToContinue) 4368 Kind = PrevTagDecl->getTagKind(); 4369 else { 4370 // Recover by making this an anonymous redefinition. 4371 Name = 0; 4372 PrevDecl = 0; 4373 Invalid = true; 4374 } 4375 } 4376 4377 if (!Invalid) { 4378 // If this is a use, just return the declaration we found. 4379 4380 // FIXME: In the future, return a variant or some other clue 4381 // for the consumer of this Decl to know it doesn't own it. 4382 // For our current ASTs this shouldn't be a problem, but will 4383 // need to be changed with DeclGroups. 4384 if (TUK == TUK_Reference || TUK == TUK_Friend) 4385 return DeclPtrTy::make(PrevDecl); 4386 4387 // Diagnose attempts to redefine a tag. 4388 if (TUK == TUK_Definition) { 4389 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4390 // If we're defining a specialization and the previous definition 4391 // is from an implicit instantiation, don't emit an error 4392 // here; we'll catch this in the general case below. 4393 if (!isExplicitSpecialization || 4394 !isa<CXXRecordDecl>(Def) || 4395 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4396 == TSK_ExplicitSpecialization) { 4397 Diag(NameLoc, diag::err_redefinition) << Name; 4398 Diag(Def->getLocation(), diag::note_previous_definition); 4399 // If this is a redefinition, recover by making this 4400 // struct be anonymous, which will make any later 4401 // references get the previous definition. 4402 Name = 0; 4403 PrevDecl = 0; 4404 Invalid = true; 4405 } 4406 } else { 4407 // If the type is currently being defined, complain 4408 // about a nested redefinition. 4409 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4410 if (Tag->isBeingDefined()) { 4411 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4412 Diag(PrevTagDecl->getLocation(), 4413 diag::note_previous_definition); 4414 Name = 0; 4415 PrevDecl = 0; 4416 Invalid = true; 4417 } 4418 } 4419 4420 // Okay, this is definition of a previously declared or referenced 4421 // tag PrevDecl. We're going to create a new Decl for it. 4422 } 4423 } 4424 // If we get here we have (another) forward declaration or we 4425 // have a definition. Just create a new decl. 4426 4427 } else { 4428 // If we get here, this is a definition of a new tag type in a nested 4429 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4430 // new decl/type. We set PrevDecl to NULL so that the entities 4431 // have distinct types. 4432 PrevDecl = 0; 4433 } 4434 // If we get here, we're going to create a new Decl. If PrevDecl 4435 // is non-NULL, it's a definition of the tag declared by 4436 // PrevDecl. If it's NULL, we have a new definition. 4437 } else { 4438 // PrevDecl is a namespace, template, or anything else 4439 // that lives in the IDNS_Tag identifier namespace. 4440 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4441 // The tag name clashes with a namespace name, issue an error and 4442 // recover by making this tag be anonymous. 4443 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4444 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4445 Name = 0; 4446 PrevDecl = 0; 4447 Invalid = true; 4448 } else { 4449 // The existing declaration isn't relevant to us; we're in a 4450 // new scope, so clear out the previous declaration. 4451 PrevDecl = 0; 4452 } 4453 } 4454 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4455 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4456 // C++ [basic.scope.pdecl]p5: 4457 // -- for an elaborated-type-specifier of the form 4458 // 4459 // class-key identifier 4460 // 4461 // if the elaborated-type-specifier is used in the 4462 // decl-specifier-seq or parameter-declaration-clause of a 4463 // function defined in namespace scope, the identifier is 4464 // declared as a class-name in the namespace that contains 4465 // the declaration; otherwise, except as a friend 4466 // declaration, the identifier is declared in the smallest 4467 // non-class, non-function-prototype scope that contains the 4468 // declaration. 4469 // 4470 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4471 // C structs and unions. 4472 // 4473 // GNU C also supports this behavior as part of its incomplete 4474 // enum types extension, while GNU C++ does not. 4475 // 4476 // Find the context where we'll be declaring the tag. 4477 // FIXME: We would like to maintain the current DeclContext as the 4478 // lexical context, 4479 while (SearchDC->isRecord()) 4480 SearchDC = SearchDC->getParent(); 4481 4482 // Find the scope where we'll be declaring the tag. 4483 while (S->isClassScope() || 4484 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4485 ((S->getFlags() & Scope::DeclScope) == 0) || 4486 (S->getEntity() && 4487 ((DeclContext *)S->getEntity())->isTransparentContext())) 4488 S = S->getParent(); 4489 4490 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4491 // C++ [namespace.memdef]p3: 4492 // If a friend declaration in a non-local class first declares a 4493 // class or function, the friend class or function is a member of 4494 // the innermost enclosing namespace. 4495 while (!SearchDC->isFileContext()) 4496 SearchDC = SearchDC->getParent(); 4497 4498 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4499 while (S->getEntity() != SearchDC) 4500 S = S->getParent(); 4501 } 4502 4503CreateNewDecl: 4504 4505 // If there is an identifier, use the location of the identifier as the 4506 // location of the decl, otherwise use the location of the struct/union 4507 // keyword. 4508 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4509 4510 // Otherwise, create a new declaration. If there is a previous 4511 // declaration of the same entity, the two will be linked via 4512 // PrevDecl. 4513 TagDecl *New; 4514 4515 if (Kind == TagDecl::TK_enum) { 4516 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4517 // enum X { A, B, C } D; D should chain to X. 4518 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4519 cast_or_null<EnumDecl>(PrevDecl)); 4520 // If this is an undefined enum, warn. 4521 if (TUK != TUK_Definition && !Invalid) { 4522 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4523 : diag::ext_forward_ref_enum; 4524 Diag(Loc, DK); 4525 } 4526 } else { 4527 // struct/union/class 4528 4529 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4530 // struct X { int A; } D; D should chain to X. 4531 if (getLangOptions().CPlusPlus) { 4532 // FIXME: Look for a way to use RecordDecl for simple structs. 4533 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4534 cast_or_null<CXXRecordDecl>(PrevDecl)); 4535 4536 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4537 StdBadAlloc = cast<CXXRecordDecl>(New); 4538 } else 4539 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4540 cast_or_null<RecordDecl>(PrevDecl)); 4541 } 4542 4543 if (Kind != TagDecl::TK_enum) { 4544 // Handle #pragma pack: if the #pragma pack stack has non-default 4545 // alignment, make up a packed attribute for this decl. These 4546 // attributes are checked when the ASTContext lays out the 4547 // structure. 4548 // 4549 // It is important for implementing the correct semantics that this 4550 // happen here (in act on tag decl). The #pragma pack stack is 4551 // maintained as a result of parser callbacks which can occur at 4552 // many points during the parsing of a struct declaration (because 4553 // the #pragma tokens are effectively skipped over during the 4554 // parsing of the struct). 4555 if (unsigned Alignment = getPragmaPackAlignment()) 4556 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4557 } 4558 4559 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4560 // C++ [dcl.typedef]p3: 4561 // [...] Similarly, in a given scope, a class or enumeration 4562 // shall not be declared with the same name as a typedef-name 4563 // that is declared in that scope and refers to a type other 4564 // than the class or enumeration itself. 4565 LookupResult Lookup; 4566 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4567 TypedefDecl *PrevTypedef = 0; 4568 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4569 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4570 4571 NamedDecl *PrevTypedefNamed = PrevTypedef; 4572 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4573 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4574 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4575 Diag(Loc, diag::err_tag_definition_of_typedef) 4576 << Context.getTypeDeclType(New) 4577 << PrevTypedef->getUnderlyingType(); 4578 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4579 Invalid = true; 4580 } 4581 } 4582 4583 // If this is a specialization of a member class (of a class template), 4584 // check the specialization. 4585 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4586 Invalid = true; 4587 4588 if (Invalid) 4589 New->setInvalidDecl(); 4590 4591 if (Attr) 4592 ProcessDeclAttributeList(S, New, Attr); 4593 4594 // If we're declaring or defining a tag in function prototype scope 4595 // in C, note that this type can only be used within the function. 4596 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4597 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4598 4599 // Set the lexical context. If the tag has a C++ scope specifier, the 4600 // lexical context will be different from the semantic context. 4601 New->setLexicalDeclContext(CurContext); 4602 4603 // Mark this as a friend decl if applicable. 4604 if (TUK == TUK_Friend) 4605 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4606 4607 // Set the access specifier. 4608 if (!Invalid && TUK != TUK_Friend) 4609 SetMemberAccessSpecifier(New, PrevDecl, AS); 4610 4611 if (TUK == TUK_Definition) 4612 New->startDefinition(); 4613 4614 // If this has an identifier, add it to the scope stack. 4615 if (TUK == TUK_Friend) { 4616 // We might be replacing an existing declaration in the lookup tables; 4617 // if so, borrow its access specifier. 4618 if (PrevDecl) 4619 New->setAccess(PrevDecl->getAccess()); 4620 4621 // Friend tag decls are visible in fairly strange ways. 4622 if (!CurContext->isDependentContext()) { 4623 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4624 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4625 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4626 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4627 } 4628 } else if (Name) { 4629 S = getNonFieldDeclScope(S); 4630 PushOnScopeChains(New, S); 4631 } else { 4632 CurContext->addDecl(New); 4633 } 4634 4635 // If this is the C FILE type, notify the AST context. 4636 if (IdentifierInfo *II = New->getIdentifier()) 4637 if (!New->isInvalidDecl() && 4638 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4639 II->isStr("FILE")) 4640 Context.setFILEDecl(New); 4641 4642 OwnedDecl = true; 4643 return DeclPtrTy::make(New); 4644} 4645 4646void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4647 AdjustDeclIfTemplate(TagD); 4648 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4649 4650 // Enter the tag context. 4651 PushDeclContext(S, Tag); 4652 4653 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4654 FieldCollector->StartClass(); 4655 4656 if (Record->getIdentifier()) { 4657 // C++ [class]p2: 4658 // [...] The class-name is also inserted into the scope of the 4659 // class itself; this is known as the injected-class-name. For 4660 // purposes of access checking, the injected-class-name is treated 4661 // as if it were a public member name. 4662 CXXRecordDecl *InjectedClassName 4663 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4664 CurContext, Record->getLocation(), 4665 Record->getIdentifier(), 4666 Record->getTagKeywordLoc(), 4667 Record); 4668 InjectedClassName->setImplicit(); 4669 InjectedClassName->setAccess(AS_public); 4670 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4671 InjectedClassName->setDescribedClassTemplate(Template); 4672 PushOnScopeChains(InjectedClassName, S); 4673 assert(InjectedClassName->isInjectedClassName() && 4674 "Broken injected-class-name"); 4675 } 4676 } 4677} 4678 4679void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4680 SourceLocation RBraceLoc) { 4681 AdjustDeclIfTemplate(TagD); 4682 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4683 Tag->setRBraceLoc(RBraceLoc); 4684 4685 if (isa<CXXRecordDecl>(Tag)) 4686 FieldCollector->FinishClass(); 4687 4688 // Exit this scope of this tag's definition. 4689 PopDeclContext(); 4690 4691 // Notify the consumer that we've defined a tag. 4692 Consumer.HandleTagDeclDefinition(Tag); 4693} 4694 4695// Note that FieldName may be null for anonymous bitfields. 4696bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4697 QualType FieldTy, const Expr *BitWidth, 4698 bool *ZeroWidth) { 4699 // Default to true; that shouldn't confuse checks for emptiness 4700 if (ZeroWidth) 4701 *ZeroWidth = true; 4702 4703 // C99 6.7.2.1p4 - verify the field type. 4704 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4705 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4706 // Handle incomplete types with specific error. 4707 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4708 return true; 4709 if (FieldName) 4710 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4711 << FieldName << FieldTy << BitWidth->getSourceRange(); 4712 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4713 << FieldTy << BitWidth->getSourceRange(); 4714 } 4715 4716 // If the bit-width is type- or value-dependent, don't try to check 4717 // it now. 4718 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4719 return false; 4720 4721 llvm::APSInt Value; 4722 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4723 return true; 4724 4725 if (Value != 0 && ZeroWidth) 4726 *ZeroWidth = false; 4727 4728 // Zero-width bitfield is ok for anonymous field. 4729 if (Value == 0 && FieldName) 4730 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4731 4732 if (Value.isSigned() && Value.isNegative()) { 4733 if (FieldName) 4734 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4735 << FieldName << Value.toString(10); 4736 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4737 << Value.toString(10); 4738 } 4739 4740 if (!FieldTy->isDependentType()) { 4741 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4742 if (Value.getZExtValue() > TypeSize) { 4743 if (FieldName) 4744 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4745 << FieldName << (unsigned)TypeSize; 4746 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4747 << (unsigned)TypeSize; 4748 } 4749 } 4750 4751 return false; 4752} 4753 4754/// ActOnField - Each field of a struct/union/class is passed into this in order 4755/// to create a FieldDecl object for it. 4756Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4757 SourceLocation DeclStart, 4758 Declarator &D, ExprTy *BitfieldWidth) { 4759 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4760 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4761 AS_public); 4762 return DeclPtrTy::make(Res); 4763} 4764 4765/// HandleField - Analyze a field of a C struct or a C++ data member. 4766/// 4767FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4768 SourceLocation DeclStart, 4769 Declarator &D, Expr *BitWidth, 4770 AccessSpecifier AS) { 4771 IdentifierInfo *II = D.getIdentifier(); 4772 SourceLocation Loc = DeclStart; 4773 if (II) Loc = D.getIdentifierLoc(); 4774 4775 DeclaratorInfo *DInfo = 0; 4776 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4777 if (getLangOptions().CPlusPlus) 4778 CheckExtraCXXDefaultArguments(D); 4779 4780 DiagnoseFunctionSpecifiers(D); 4781 4782 if (D.getDeclSpec().isThreadSpecified()) 4783 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4784 4785 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4786 4787 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4788 // Maybe we will complain about the shadowed template parameter. 4789 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4790 // Just pretend that we didn't see the previous declaration. 4791 PrevDecl = 0; 4792 } 4793 4794 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4795 PrevDecl = 0; 4796 4797 bool Mutable 4798 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4799 SourceLocation TSSL = D.getSourceRange().getBegin(); 4800 FieldDecl *NewFD 4801 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4802 AS, PrevDecl, &D); 4803 if (NewFD->isInvalidDecl() && PrevDecl) { 4804 // Don't introduce NewFD into scope; there's already something 4805 // with the same name in the same scope. 4806 } else if (II) { 4807 PushOnScopeChains(NewFD, S); 4808 } else 4809 Record->addDecl(NewFD); 4810 4811 return NewFD; 4812} 4813 4814/// \brief Build a new FieldDecl and check its well-formedness. 4815/// 4816/// This routine builds a new FieldDecl given the fields name, type, 4817/// record, etc. \p PrevDecl should refer to any previous declaration 4818/// with the same name and in the same scope as the field to be 4819/// created. 4820/// 4821/// \returns a new FieldDecl. 4822/// 4823/// \todo The Declarator argument is a hack. It will be removed once 4824FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4825 DeclaratorInfo *DInfo, 4826 RecordDecl *Record, SourceLocation Loc, 4827 bool Mutable, Expr *BitWidth, 4828 SourceLocation TSSL, 4829 AccessSpecifier AS, NamedDecl *PrevDecl, 4830 Declarator *D) { 4831 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4832 bool InvalidDecl = false; 4833 if (D) InvalidDecl = D->isInvalidType(); 4834 4835 // If we receive a broken type, recover by assuming 'int' and 4836 // marking this declaration as invalid. 4837 if (T.isNull()) { 4838 InvalidDecl = true; 4839 T = Context.IntTy; 4840 } 4841 4842 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4843 // than a variably modified type. 4844 if (T->isVariablyModifiedType()) { 4845 bool SizeIsNegative; 4846 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4847 SizeIsNegative); 4848 if (!FixedTy.isNull()) { 4849 Diag(Loc, diag::warn_illegal_constant_array_size); 4850 T = FixedTy; 4851 } else { 4852 if (SizeIsNegative) 4853 Diag(Loc, diag::err_typecheck_negative_array_size); 4854 else 4855 Diag(Loc, diag::err_typecheck_field_variable_size); 4856 InvalidDecl = true; 4857 } 4858 } 4859 4860 // Fields can not have abstract class types 4861 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4862 AbstractFieldType)) 4863 InvalidDecl = true; 4864 4865 bool ZeroWidth = false; 4866 // If this is declared as a bit-field, check the bit-field. 4867 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4868 InvalidDecl = true; 4869 DeleteExpr(BitWidth); 4870 BitWidth = 0; 4871 ZeroWidth = false; 4872 } 4873 4874 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4875 BitWidth, Mutable); 4876 if (InvalidDecl) 4877 NewFD->setInvalidDecl(); 4878 4879 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4880 Diag(Loc, diag::err_duplicate_member) << II; 4881 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4882 NewFD->setInvalidDecl(); 4883 } 4884 4885 if (getLangOptions().CPlusPlus) { 4886 QualType EltTy = Context.getBaseElementType(T); 4887 4888 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4889 4890 if (!T->isPODType()) 4891 CXXRecord->setPOD(false); 4892 if (!ZeroWidth) 4893 CXXRecord->setEmpty(false); 4894 4895 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4896 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4897 4898 if (!RDecl->hasTrivialConstructor()) 4899 CXXRecord->setHasTrivialConstructor(false); 4900 if (!RDecl->hasTrivialCopyConstructor()) 4901 CXXRecord->setHasTrivialCopyConstructor(false); 4902 if (!RDecl->hasTrivialCopyAssignment()) 4903 CXXRecord->setHasTrivialCopyAssignment(false); 4904 if (!RDecl->hasTrivialDestructor()) 4905 CXXRecord->setHasTrivialDestructor(false); 4906 4907 // C++ 9.5p1: An object of a class with a non-trivial 4908 // constructor, a non-trivial copy constructor, a non-trivial 4909 // destructor, or a non-trivial copy assignment operator 4910 // cannot be a member of a union, nor can an array of such 4911 // objects. 4912 // TODO: C++0x alters this restriction significantly. 4913 if (Record->isUnion()) { 4914 // We check for copy constructors before constructors 4915 // because otherwise we'll never get complaints about 4916 // copy constructors. 4917 4918 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4919 4920 CXXSpecialMember member; 4921 if (!RDecl->hasTrivialCopyConstructor()) 4922 member = CXXCopyConstructor; 4923 else if (!RDecl->hasTrivialConstructor()) 4924 member = CXXDefaultConstructor; 4925 else if (!RDecl->hasTrivialCopyAssignment()) 4926 member = CXXCopyAssignment; 4927 else if (!RDecl->hasTrivialDestructor()) 4928 member = CXXDestructor; 4929 else 4930 member = invalid; 4931 4932 if (member != invalid) { 4933 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4934 DiagnoseNontrivial(RT, member); 4935 NewFD->setInvalidDecl(); 4936 } 4937 } 4938 } 4939 } 4940 4941 // FIXME: We need to pass in the attributes given an AST 4942 // representation, not a parser representation. 4943 if (D) 4944 // FIXME: What to pass instead of TUScope? 4945 ProcessDeclAttributes(TUScope, NewFD, *D); 4946 4947 if (T.isObjCGCWeak()) 4948 Diag(Loc, diag::warn_attribute_weak_on_field); 4949 4950 NewFD->setAccess(AS); 4951 4952 // C++ [dcl.init.aggr]p1: 4953 // An aggregate is an array or a class (clause 9) with [...] no 4954 // private or protected non-static data members (clause 11). 4955 // A POD must be an aggregate. 4956 if (getLangOptions().CPlusPlus && 4957 (AS == AS_private || AS == AS_protected)) { 4958 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4959 CXXRecord->setAggregate(false); 4960 CXXRecord->setPOD(false); 4961 } 4962 4963 return NewFD; 4964} 4965 4966/// DiagnoseNontrivial - Given that a class has a non-trivial 4967/// special member, figure out why. 4968void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4969 QualType QT(T, 0U); 4970 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4971 4972 // Check whether the member was user-declared. 4973 switch (member) { 4974 case CXXDefaultConstructor: 4975 if (RD->hasUserDeclaredConstructor()) { 4976 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4977 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 4978 const FunctionDecl *body = 0; 4979 ci->getBody(body); 4980 if (!body || 4981 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 4982 SourceLocation CtorLoc = ci->getLocation(); 4983 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4984 return; 4985 } 4986 } 4987 4988 assert(0 && "found no user-declared constructors"); 4989 return; 4990 } 4991 break; 4992 4993 case CXXCopyConstructor: 4994 if (RD->hasUserDeclaredCopyConstructor()) { 4995 SourceLocation CtorLoc = 4996 RD->getCopyConstructor(Context, 0)->getLocation(); 4997 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4998 return; 4999 } 5000 break; 5001 5002 case CXXCopyAssignment: 5003 if (RD->hasUserDeclaredCopyAssignment()) { 5004 // FIXME: this should use the location of the copy 5005 // assignment, not the type. 5006 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5007 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5008 return; 5009 } 5010 break; 5011 5012 case CXXDestructor: 5013 if (RD->hasUserDeclaredDestructor()) { 5014 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5015 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5016 return; 5017 } 5018 break; 5019 } 5020 5021 typedef CXXRecordDecl::base_class_iterator base_iter; 5022 5023 // Virtual bases and members inhibit trivial copying/construction, 5024 // but not trivial destruction. 5025 if (member != CXXDestructor) { 5026 // Check for virtual bases. vbases includes indirect virtual bases, 5027 // so we just iterate through the direct bases. 5028 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5029 if (bi->isVirtual()) { 5030 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5031 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5032 return; 5033 } 5034 5035 // Check for virtual methods. 5036 typedef CXXRecordDecl::method_iterator meth_iter; 5037 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5038 ++mi) { 5039 if (mi->isVirtual()) { 5040 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5041 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5042 return; 5043 } 5044 } 5045 } 5046 5047 bool (CXXRecordDecl::*hasTrivial)() const; 5048 switch (member) { 5049 case CXXDefaultConstructor: 5050 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5051 case CXXCopyConstructor: 5052 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5053 case CXXCopyAssignment: 5054 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5055 case CXXDestructor: 5056 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5057 default: 5058 assert(0 && "unexpected special member"); return; 5059 } 5060 5061 // Check for nontrivial bases (and recurse). 5062 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5063 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5064 assert(BaseRT && "Don't know how to handle dependent bases"); 5065 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5066 if (!(BaseRecTy->*hasTrivial)()) { 5067 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5068 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5069 DiagnoseNontrivial(BaseRT, member); 5070 return; 5071 } 5072 } 5073 5074 // Check for nontrivial members (and recurse). 5075 typedef RecordDecl::field_iterator field_iter; 5076 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5077 ++fi) { 5078 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5079 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5080 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5081 5082 if (!(EltRD->*hasTrivial)()) { 5083 SourceLocation FLoc = (*fi)->getLocation(); 5084 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5085 DiagnoseNontrivial(EltRT, member); 5086 return; 5087 } 5088 } 5089 } 5090 5091 assert(0 && "found no explanation for non-trivial member"); 5092} 5093 5094/// TranslateIvarVisibility - Translate visibility from a token ID to an 5095/// AST enum value. 5096static ObjCIvarDecl::AccessControl 5097TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5098 switch (ivarVisibility) { 5099 default: assert(0 && "Unknown visitibility kind"); 5100 case tok::objc_private: return ObjCIvarDecl::Private; 5101 case tok::objc_public: return ObjCIvarDecl::Public; 5102 case tok::objc_protected: return ObjCIvarDecl::Protected; 5103 case tok::objc_package: return ObjCIvarDecl::Package; 5104 } 5105} 5106 5107/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5108/// in order to create an IvarDecl object for it. 5109Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5110 SourceLocation DeclStart, 5111 DeclPtrTy IntfDecl, 5112 Declarator &D, ExprTy *BitfieldWidth, 5113 tok::ObjCKeywordKind Visibility) { 5114 5115 IdentifierInfo *II = D.getIdentifier(); 5116 Expr *BitWidth = (Expr*)BitfieldWidth; 5117 SourceLocation Loc = DeclStart; 5118 if (II) Loc = D.getIdentifierLoc(); 5119 5120 // FIXME: Unnamed fields can be handled in various different ways, for 5121 // example, unnamed unions inject all members into the struct namespace! 5122 5123 DeclaratorInfo *DInfo = 0; 5124 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5125 5126 if (BitWidth) { 5127 // 6.7.2.1p3, 6.7.2.1p4 5128 if (VerifyBitField(Loc, II, T, BitWidth)) { 5129 D.setInvalidType(); 5130 DeleteExpr(BitWidth); 5131 BitWidth = 0; 5132 } 5133 } else { 5134 // Not a bitfield. 5135 5136 // validate II. 5137 5138 } 5139 5140 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5141 // than a variably modified type. 5142 if (T->isVariablyModifiedType()) { 5143 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5144 D.setInvalidType(); 5145 } 5146 5147 // Get the visibility (access control) for this ivar. 5148 ObjCIvarDecl::AccessControl ac = 5149 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5150 : ObjCIvarDecl::None; 5151 // Must set ivar's DeclContext to its enclosing interface. 5152 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5153 DeclContext *EnclosingContext; 5154 if (ObjCImplementationDecl *IMPDecl = 5155 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5156 // Case of ivar declared in an implementation. Context is that of its class. 5157 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5158 assert(IDecl && "No class- ActOnIvar"); 5159 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5160 } else 5161 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5162 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5163 5164 // Construct the decl. 5165 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5166 EnclosingContext, Loc, II, T, 5167 DInfo, ac, (Expr *)BitfieldWidth); 5168 5169 if (II) { 5170 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5171 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5172 && !isa<TagDecl>(PrevDecl)) { 5173 Diag(Loc, diag::err_duplicate_member) << II; 5174 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5175 NewID->setInvalidDecl(); 5176 } 5177 } 5178 5179 // Process attributes attached to the ivar. 5180 ProcessDeclAttributes(S, NewID, D); 5181 5182 if (D.isInvalidType()) 5183 NewID->setInvalidDecl(); 5184 5185 if (II) { 5186 // FIXME: When interfaces are DeclContexts, we'll need to add 5187 // these to the interface. 5188 S->AddDecl(DeclPtrTy::make(NewID)); 5189 IdResolver.AddDecl(NewID); 5190 } 5191 5192 return DeclPtrTy::make(NewID); 5193} 5194 5195void Sema::ActOnFields(Scope* S, 5196 SourceLocation RecLoc, DeclPtrTy RecDecl, 5197 DeclPtrTy *Fields, unsigned NumFields, 5198 SourceLocation LBrac, SourceLocation RBrac, 5199 AttributeList *Attr) { 5200 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5201 assert(EnclosingDecl && "missing record or interface decl"); 5202 5203 // If the decl this is being inserted into is invalid, then it may be a 5204 // redeclaration or some other bogus case. Don't try to add fields to it. 5205 if (EnclosingDecl->isInvalidDecl()) { 5206 // FIXME: Deallocate fields? 5207 return; 5208 } 5209 5210 5211 // Verify that all the fields are okay. 5212 unsigned NumNamedMembers = 0; 5213 llvm::SmallVector<FieldDecl*, 32> RecFields; 5214 5215 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5216 for (unsigned i = 0; i != NumFields; ++i) { 5217 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5218 5219 // Get the type for the field. 5220 Type *FDTy = FD->getType().getTypePtr(); 5221 5222 if (!FD->isAnonymousStructOrUnion()) { 5223 // Remember all fields written by the user. 5224 RecFields.push_back(FD); 5225 } 5226 5227 // If the field is already invalid for some reason, don't emit more 5228 // diagnostics about it. 5229 if (FD->isInvalidDecl()) 5230 continue; 5231 5232 // C99 6.7.2.1p2: 5233 // A structure or union shall not contain a member with 5234 // incomplete or function type (hence, a structure shall not 5235 // contain an instance of itself, but may contain a pointer to 5236 // an instance of itself), except that the last member of a 5237 // structure with more than one named member may have incomplete 5238 // array type; such a structure (and any union containing, 5239 // possibly recursively, a member that is such a structure) 5240 // shall not be a member of a structure or an element of an 5241 // array. 5242 if (FDTy->isFunctionType()) { 5243 // Field declared as a function. 5244 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5245 << FD->getDeclName(); 5246 FD->setInvalidDecl(); 5247 EnclosingDecl->setInvalidDecl(); 5248 continue; 5249 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5250 Record && Record->isStruct()) { 5251 // Flexible array member. 5252 if (NumNamedMembers < 1) { 5253 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5254 << FD->getDeclName(); 5255 FD->setInvalidDecl(); 5256 EnclosingDecl->setInvalidDecl(); 5257 continue; 5258 } 5259 // Okay, we have a legal flexible array member at the end of the struct. 5260 if (Record) 5261 Record->setHasFlexibleArrayMember(true); 5262 } else if (!FDTy->isDependentType() && 5263 RequireCompleteType(FD->getLocation(), FD->getType(), 5264 diag::err_field_incomplete)) { 5265 // Incomplete type 5266 FD->setInvalidDecl(); 5267 EnclosingDecl->setInvalidDecl(); 5268 continue; 5269 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5270 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5271 // If this is a member of a union, then entire union becomes "flexible". 5272 if (Record && Record->isUnion()) { 5273 Record->setHasFlexibleArrayMember(true); 5274 } else { 5275 // If this is a struct/class and this is not the last element, reject 5276 // it. Note that GCC supports variable sized arrays in the middle of 5277 // structures. 5278 if (i != NumFields-1) 5279 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5280 << FD->getDeclName() << FD->getType(); 5281 else { 5282 // We support flexible arrays at the end of structs in 5283 // other structs as an extension. 5284 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5285 << FD->getDeclName(); 5286 if (Record) 5287 Record->setHasFlexibleArrayMember(true); 5288 } 5289 } 5290 } 5291 if (Record && FDTTy->getDecl()->hasObjectMember()) 5292 Record->setHasObjectMember(true); 5293 } else if (FDTy->isObjCInterfaceType()) { 5294 /// A field cannot be an Objective-c object 5295 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5296 FD->setInvalidDecl(); 5297 EnclosingDecl->setInvalidDecl(); 5298 continue; 5299 } else if (getLangOptions().ObjC1 && 5300 getLangOptions().getGCMode() != LangOptions::NonGC && 5301 Record && 5302 (FD->getType()->isObjCObjectPointerType() || 5303 FD->getType().isObjCGCStrong())) 5304 Record->setHasObjectMember(true); 5305 // Keep track of the number of named members. 5306 if (FD->getIdentifier()) 5307 ++NumNamedMembers; 5308 } 5309 5310 // Okay, we successfully defined 'Record'. 5311 if (Record) { 5312 Record->completeDefinition(Context); 5313 } else { 5314 ObjCIvarDecl **ClsFields = 5315 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5316 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5317 ID->setIVarList(ClsFields, RecFields.size(), Context); 5318 ID->setLocEnd(RBrac); 5319 // Add ivar's to class's DeclContext. 5320 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5321 ClsFields[i]->setLexicalDeclContext(ID); 5322 ID->addDecl(ClsFields[i]); 5323 } 5324 // Must enforce the rule that ivars in the base classes may not be 5325 // duplicates. 5326 if (ID->getSuperClass()) { 5327 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5328 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5329 ObjCIvarDecl* Ivar = (*IVI); 5330 5331 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5332 ObjCIvarDecl* prevIvar = 5333 ID->getSuperClass()->lookupInstanceVariable(II); 5334 if (prevIvar) { 5335 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5336 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5337 } 5338 } 5339 } 5340 } 5341 } else if (ObjCImplementationDecl *IMPDecl = 5342 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5343 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5344 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5345 // Ivar declared in @implementation never belongs to the implementation. 5346 // Only it is in implementation's lexical context. 5347 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5348 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5349 } 5350 } 5351 5352 if (Attr) 5353 ProcessDeclAttributeList(S, Record, Attr); 5354} 5355 5356EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5357 EnumConstantDecl *LastEnumConst, 5358 SourceLocation IdLoc, 5359 IdentifierInfo *Id, 5360 ExprArg val) { 5361 Expr *Val = (Expr *)val.get(); 5362 5363 llvm::APSInt EnumVal(32); 5364 QualType EltTy; 5365 if (Val && !Val->isTypeDependent()) { 5366 // Make sure to promote the operand type to int. 5367 UsualUnaryConversions(Val); 5368 if (Val != val.get()) { 5369 val.release(); 5370 val = Val; 5371 } 5372 5373 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5374 SourceLocation ExpLoc; 5375 if (!Val->isValueDependent() && 5376 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5377 Val = 0; 5378 } else { 5379 EltTy = Val->getType(); 5380 } 5381 } 5382 5383 if (!Val) { 5384 if (LastEnumConst) { 5385 // Assign the last value + 1. 5386 EnumVal = LastEnumConst->getInitVal(); 5387 ++EnumVal; 5388 5389 // Check for overflow on increment. 5390 if (EnumVal < LastEnumConst->getInitVal()) 5391 Diag(IdLoc, diag::warn_enum_value_overflow); 5392 5393 EltTy = LastEnumConst->getType(); 5394 } else { 5395 // First value, set to zero. 5396 EltTy = Context.IntTy; 5397 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5398 } 5399 } 5400 5401 val.release(); 5402 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5403 Val, EnumVal); 5404} 5405 5406 5407Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5408 DeclPtrTy lastEnumConst, 5409 SourceLocation IdLoc, 5410 IdentifierInfo *Id, 5411 SourceLocation EqualLoc, ExprTy *val) { 5412 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5413 EnumConstantDecl *LastEnumConst = 5414 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5415 Expr *Val = static_cast<Expr*>(val); 5416 5417 // The scope passed in may not be a decl scope. Zip up the scope tree until 5418 // we find one that is. 5419 S = getNonFieldDeclScope(S); 5420 5421 // Verify that there isn't already something declared with this name in this 5422 // scope. 5423 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5424 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5425 // Maybe we will complain about the shadowed template parameter. 5426 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5427 // Just pretend that we didn't see the previous declaration. 5428 PrevDecl = 0; 5429 } 5430 5431 if (PrevDecl) { 5432 // When in C++, we may get a TagDecl with the same name; in this case the 5433 // enum constant will 'hide' the tag. 5434 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5435 "Received TagDecl when not in C++!"); 5436 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5437 if (isa<EnumConstantDecl>(PrevDecl)) 5438 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5439 else 5440 Diag(IdLoc, diag::err_redefinition) << Id; 5441 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5442 if (Val) Val->Destroy(Context); 5443 return DeclPtrTy(); 5444 } 5445 } 5446 5447 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5448 IdLoc, Id, Owned(Val)); 5449 5450 // Register this decl in the current scope stack. 5451 if (New) 5452 PushOnScopeChains(New, S); 5453 5454 return DeclPtrTy::make(New); 5455} 5456 5457void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5458 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5459 DeclPtrTy *Elements, unsigned NumElements, 5460 Scope *S, AttributeList *Attr) { 5461 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5462 QualType EnumType = Context.getTypeDeclType(Enum); 5463 5464 if (Attr) 5465 ProcessDeclAttributeList(S, Enum, Attr); 5466 5467 // TODO: If the result value doesn't fit in an int, it must be a long or long 5468 // long value. ISO C does not support this, but GCC does as an extension, 5469 // emit a warning. 5470 unsigned IntWidth = Context.Target.getIntWidth(); 5471 unsigned CharWidth = Context.Target.getCharWidth(); 5472 unsigned ShortWidth = Context.Target.getShortWidth(); 5473 5474 // Verify that all the values are okay, compute the size of the values, and 5475 // reverse the list. 5476 unsigned NumNegativeBits = 0; 5477 unsigned NumPositiveBits = 0; 5478 5479 // Keep track of whether all elements have type int. 5480 bool AllElementsInt = true; 5481 5482 for (unsigned i = 0; i != NumElements; ++i) { 5483 EnumConstantDecl *ECD = 5484 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5485 if (!ECD) continue; // Already issued a diagnostic. 5486 5487 // If the enum value doesn't fit in an int, emit an extension warning. 5488 const llvm::APSInt &InitVal = ECD->getInitVal(); 5489 assert(InitVal.getBitWidth() >= IntWidth && 5490 "Should have promoted value to int"); 5491 if (InitVal.getBitWidth() > IntWidth) { 5492 llvm::APSInt V(InitVal); 5493 V.trunc(IntWidth); 5494 V.extend(InitVal.getBitWidth()); 5495 if (V != InitVal) 5496 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5497 << InitVal.toString(10); 5498 } 5499 5500 // Keep track of the size of positive and negative values. 5501 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5502 NumPositiveBits = std::max(NumPositiveBits, 5503 (unsigned)InitVal.getActiveBits()); 5504 else 5505 NumNegativeBits = std::max(NumNegativeBits, 5506 (unsigned)InitVal.getMinSignedBits()); 5507 5508 // Keep track of whether every enum element has type int (very commmon). 5509 if (AllElementsInt) 5510 AllElementsInt = ECD->getType() == Context.IntTy; 5511 } 5512 5513 // Figure out the type that should be used for this enum. 5514 // FIXME: Support -fshort-enums. 5515 QualType BestType; 5516 unsigned BestWidth; 5517 5518 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5519 5520 if (NumNegativeBits) { 5521 // If there is a negative value, figure out the smallest integer type (of 5522 // int/long/longlong) that fits. 5523 // If it's packed, check also if it fits a char or a short. 5524 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5525 BestType = Context.SignedCharTy; 5526 BestWidth = CharWidth; 5527 } else if (Packed && NumNegativeBits <= ShortWidth && 5528 NumPositiveBits < ShortWidth) { 5529 BestType = Context.ShortTy; 5530 BestWidth = ShortWidth; 5531 } 5532 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5533 BestType = Context.IntTy; 5534 BestWidth = IntWidth; 5535 } else { 5536 BestWidth = Context.Target.getLongWidth(); 5537 5538 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5539 BestType = Context.LongTy; 5540 else { 5541 BestWidth = Context.Target.getLongLongWidth(); 5542 5543 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5544 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5545 BestType = Context.LongLongTy; 5546 } 5547 } 5548 } else { 5549 // If there is no negative value, figure out which of uint, ulong, ulonglong 5550 // fits. 5551 // If it's packed, check also if it fits a char or a short. 5552 if (Packed && NumPositiveBits <= CharWidth) { 5553 BestType = Context.UnsignedCharTy; 5554 BestWidth = CharWidth; 5555 } else if (Packed && NumPositiveBits <= ShortWidth) { 5556 BestType = Context.UnsignedShortTy; 5557 BestWidth = ShortWidth; 5558 } 5559 else if (NumPositiveBits <= IntWidth) { 5560 BestType = Context.UnsignedIntTy; 5561 BestWidth = IntWidth; 5562 } else if (NumPositiveBits <= 5563 (BestWidth = Context.Target.getLongWidth())) { 5564 BestType = Context.UnsignedLongTy; 5565 } else { 5566 BestWidth = Context.Target.getLongLongWidth(); 5567 assert(NumPositiveBits <= BestWidth && 5568 "How could an initializer get larger than ULL?"); 5569 BestType = Context.UnsignedLongLongTy; 5570 } 5571 } 5572 5573 // Loop over all of the enumerator constants, changing their types to match 5574 // the type of the enum if needed. 5575 for (unsigned i = 0; i != NumElements; ++i) { 5576 EnumConstantDecl *ECD = 5577 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5578 if (!ECD) continue; // Already issued a diagnostic. 5579 5580 // Standard C says the enumerators have int type, but we allow, as an 5581 // extension, the enumerators to be larger than int size. If each 5582 // enumerator value fits in an int, type it as an int, otherwise type it the 5583 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5584 // that X has type 'int', not 'unsigned'. 5585 if (ECD->getType() == Context.IntTy) { 5586 // Make sure the init value is signed. 5587 llvm::APSInt IV = ECD->getInitVal(); 5588 IV.setIsSigned(true); 5589 ECD->setInitVal(IV); 5590 5591 if (getLangOptions().CPlusPlus) 5592 // C++ [dcl.enum]p4: Following the closing brace of an 5593 // enum-specifier, each enumerator has the type of its 5594 // enumeration. 5595 ECD->setType(EnumType); 5596 continue; // Already int type. 5597 } 5598 5599 // Determine whether the value fits into an int. 5600 llvm::APSInt InitVal = ECD->getInitVal(); 5601 bool FitsInInt; 5602 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5603 FitsInInt = InitVal.getActiveBits() < IntWidth; 5604 else 5605 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5606 5607 // If it fits into an integer type, force it. Otherwise force it to match 5608 // the enum decl type. 5609 QualType NewTy; 5610 unsigned NewWidth; 5611 bool NewSign; 5612 if (FitsInInt) { 5613 NewTy = Context.IntTy; 5614 NewWidth = IntWidth; 5615 NewSign = true; 5616 } else if (ECD->getType() == BestType) { 5617 // Already the right type! 5618 if (getLangOptions().CPlusPlus) 5619 // C++ [dcl.enum]p4: Following the closing brace of an 5620 // enum-specifier, each enumerator has the type of its 5621 // enumeration. 5622 ECD->setType(EnumType); 5623 continue; 5624 } else { 5625 NewTy = BestType; 5626 NewWidth = BestWidth; 5627 NewSign = BestType->isSignedIntegerType(); 5628 } 5629 5630 // Adjust the APSInt value. 5631 InitVal.extOrTrunc(NewWidth); 5632 InitVal.setIsSigned(NewSign); 5633 ECD->setInitVal(InitVal); 5634 5635 // Adjust the Expr initializer and type. 5636 if (ECD->getInitExpr()) 5637 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5638 CastExpr::CK_IntegralCast, 5639 ECD->getInitExpr(), 5640 /*isLvalue=*/false)); 5641 if (getLangOptions().CPlusPlus) 5642 // C++ [dcl.enum]p4: Following the closing brace of an 5643 // enum-specifier, each enumerator has the type of its 5644 // enumeration. 5645 ECD->setType(EnumType); 5646 else 5647 ECD->setType(NewTy); 5648 } 5649 5650 Enum->completeDefinition(Context, BestType); 5651} 5652 5653Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5654 ExprArg expr) { 5655 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5656 5657 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5658 Loc, AsmString); 5659 CurContext->addDecl(New); 5660 return DeclPtrTy::make(New); 5661} 5662 5663void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5664 SourceLocation PragmaLoc, 5665 SourceLocation NameLoc) { 5666 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5667 5668 if (PrevDecl) { 5669 PrevDecl->addAttr(::new (Context) WeakAttr()); 5670 } else { 5671 (void)WeakUndeclaredIdentifiers.insert( 5672 std::pair<IdentifierInfo*,WeakInfo> 5673 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5674 } 5675} 5676 5677void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5678 IdentifierInfo* AliasName, 5679 SourceLocation PragmaLoc, 5680 SourceLocation NameLoc, 5681 SourceLocation AliasNameLoc) { 5682 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5683 WeakInfo W = WeakInfo(Name, NameLoc); 5684 5685 if (PrevDecl) { 5686 if (!PrevDecl->hasAttr<AliasAttr>()) 5687 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5688 DeclApplyPragmaWeak(TUScope, ND, W); 5689 } else { 5690 (void)WeakUndeclaredIdentifiers.insert( 5691 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5692 } 5693} 5694