SemaDecl.cpp revision 7ba107a1863ddfa1664555854f0d7bdb3c491c92
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/Analysis/CFG.h" 19#include "clang/AST/CXXInheritance.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Parse/ParseDiagnostic.h" 27#include "clang/Parse/Template.h" 28#include "clang/Basic/PartialDiagnostic.h" 29#include "clang/Basic/SourceManager.h" 30#include "clang/Basic/TargetInfo.h" 31// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 32#include "clang/Lex/Preprocessor.h" 33#include "clang/Lex/HeaderSearch.h" 34#include "llvm/ADT/BitVector.h" 35#include "llvm/ADT/STLExtras.h" 36#include <algorithm> 37#include <cstring> 38#include <functional> 39#include <queue> 40using namespace clang; 41 42/// getDeclName - Return a pretty name for the specified decl if possible, or 43/// an empty string if not. This is used for pretty crash reporting. 44std::string Sema::getDeclName(DeclPtrTy d) { 45 Decl *D = d.getAs<Decl>(); 46 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 47 return DN->getQualifiedNameAsString(); 48 return ""; 49} 50 51Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 52 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 53} 54 55/// \brief If the identifier refers to a type name within this scope, 56/// return the declaration of that type. 57/// 58/// This routine performs ordinary name lookup of the identifier II 59/// within the given scope, with optional C++ scope specifier SS, to 60/// determine whether the name refers to a type. If so, returns an 61/// opaque pointer (actually a QualType) corresponding to that 62/// type. Otherwise, returns NULL. 63/// 64/// If name lookup results in an ambiguity, this routine will complain 65/// and then return NULL. 66Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 67 Scope *S, const CXXScopeSpec *SS, 68 bool isClassName) { 69 // C++ [temp.res]p3: 70 // A qualified-id that refers to a type and in which the 71 // nested-name-specifier depends on a template-parameter (14.6.2) 72 // shall be prefixed by the keyword typename to indicate that the 73 // qualified-id denotes a type, forming an 74 // elaborated-type-specifier (7.1.5.3). 75 // 76 // We therefore do not perform any name lookup if the result would 77 // refer to a member of an unknown specialization. 78 if (SS && isUnknownSpecialization(*SS)) { 79 if (!isClassName) 80 return 0; 81 82 // We know from the grammar that this name refers to a type, so build a 83 // TypenameType node to describe the type. 84 // FIXME: Record somewhere that this TypenameType node has no "typename" 85 // keyword associated with it. 86 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 87 II, SS->getRange()).getAsOpaquePtr(); 88 } 89 90 LookupResult Result(*this, &II, NameLoc, LookupOrdinaryName); 91 LookupParsedName(Result, S, SS, false); 92 93 NamedDecl *IIDecl = 0; 94 switch (Result.getResultKind()) { 95 case LookupResult::NotFound: 96 case LookupResult::FoundOverloaded: 97 case LookupResult::FoundUnresolvedValue: 98 return 0; 99 100 case LookupResult::Ambiguous: 101 // Recover from type-hiding ambiguities by hiding the type. We'll 102 // do the lookup again when looking for an object, and we can 103 // diagnose the error then. If we don't do this, then the error 104 // about hiding the type will be immediately followed by an error 105 // that only makes sense if the identifier was treated like a type. 106 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 107 Result.suppressDiagnostics(); 108 return 0; 109 } 110 111 // Look to see if we have a type anywhere in the list of results. 112 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 113 Res != ResEnd; ++Res) { 114 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 115 if (!IIDecl || 116 (*Res)->getLocation().getRawEncoding() < 117 IIDecl->getLocation().getRawEncoding()) 118 IIDecl = *Res; 119 } 120 } 121 122 if (!IIDecl) { 123 // None of the entities we found is a type, so there is no way 124 // to even assume that the result is a type. In this case, don't 125 // complain about the ambiguity. The parser will either try to 126 // perform this lookup again (e.g., as an object name), which 127 // will produce the ambiguity, or will complain that it expected 128 // a type name. 129 Result.suppressDiagnostics(); 130 return 0; 131 } 132 133 // We found a type within the ambiguous lookup; diagnose the 134 // ambiguity and then return that type. This might be the right 135 // answer, or it might not be, but it suppresses any attempt to 136 // perform the name lookup again. 137 break; 138 139 case LookupResult::Found: 140 IIDecl = Result.getFoundDecl(); 141 break; 142 } 143 144 assert(IIDecl && "Didn't find decl"); 145 146 QualType T; 147 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 148 DiagnoseUseOfDecl(IIDecl, NameLoc); 149 150 // C++ [temp.local]p2: 151 // Within the scope of a class template specialization or 152 // partial specialization, when the injected-class-name is 153 // not followed by a <, it is equivalent to the 154 // injected-class-name followed by the template-argument s 155 // of the class template specialization or partial 156 // specialization enclosed in <>. 157 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 158 if (RD->isInjectedClassName()) 159 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 160 T = Template->getInjectedClassNameType(Context); 161 162 if (T.isNull()) 163 T = Context.getTypeDeclType(TD); 164 165 if (SS) 166 T = getQualifiedNameType(*SS, T); 167 168 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 169 T = Context.getObjCInterfaceType(IDecl); 170 } else if (UnresolvedUsingTypenameDecl *UUDecl = 171 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 172 // FIXME: preserve source structure information. 173 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 174 } else { 175 // If it's not plausibly a type, suppress diagnostics. 176 Result.suppressDiagnostics(); 177 return 0; 178 } 179 180 return T.getAsOpaquePtr(); 181} 182 183/// isTagName() - This method is called *for error recovery purposes only* 184/// to determine if the specified name is a valid tag name ("struct foo"). If 185/// so, this returns the TST for the tag corresponding to it (TST_enum, 186/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 187/// where the user forgot to specify the tag. 188DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 189 // Do a tag name lookup in this scope. 190 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 191 LookupName(R, S, false); 192 R.suppressDiagnostics(); 193 if (R.getResultKind() == LookupResult::Found) 194 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 195 switch (TD->getTagKind()) { 196 case TagDecl::TK_struct: return DeclSpec::TST_struct; 197 case TagDecl::TK_union: return DeclSpec::TST_union; 198 case TagDecl::TK_class: return DeclSpec::TST_class; 199 case TagDecl::TK_enum: return DeclSpec::TST_enum; 200 } 201 } 202 203 return DeclSpec::TST_unspecified; 204} 205 206bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 207 SourceLocation IILoc, 208 Scope *S, 209 const CXXScopeSpec *SS, 210 TypeTy *&SuggestedType) { 211 // We don't have anything to suggest (yet). 212 SuggestedType = 0; 213 214 // FIXME: Should we move the logic that tries to recover from a missing tag 215 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 216 217 if (!SS) 218 Diag(IILoc, diag::err_unknown_typename) << &II; 219 else if (DeclContext *DC = computeDeclContext(*SS, false)) 220 Diag(IILoc, diag::err_typename_nested_not_found) 221 << &II << DC << SS->getRange(); 222 else if (isDependentScopeSpecifier(*SS)) { 223 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 224 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 225 << SourceRange(SS->getRange().getBegin(), IILoc) 226 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 227 "typename "); 228 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 229 } else { 230 assert(SS && SS->isInvalid() && 231 "Invalid scope specifier has already been diagnosed"); 232 } 233 234 return true; 235} 236 237// Determines the context to return to after temporarily entering a 238// context. This depends in an unnecessarily complicated way on the 239// exact ordering of callbacks from the parser. 240DeclContext *Sema::getContainingDC(DeclContext *DC) { 241 242 // Functions defined inline within classes aren't parsed until we've 243 // finished parsing the top-level class, so the top-level class is 244 // the context we'll need to return to. 245 if (isa<FunctionDecl>(DC)) { 246 DC = DC->getLexicalParent(); 247 248 // A function not defined within a class will always return to its 249 // lexical context. 250 if (!isa<CXXRecordDecl>(DC)) 251 return DC; 252 253 // A C++ inline method/friend is parsed *after* the topmost class 254 // it was declared in is fully parsed ("complete"); the topmost 255 // class is the context we need to return to. 256 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 257 DC = RD; 258 259 // Return the declaration context of the topmost class the inline method is 260 // declared in. 261 return DC; 262 } 263 264 if (isa<ObjCMethodDecl>(DC)) 265 return Context.getTranslationUnitDecl(); 266 267 return DC->getLexicalParent(); 268} 269 270void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 271 assert(getContainingDC(DC) == CurContext && 272 "The next DeclContext should be lexically contained in the current one."); 273 CurContext = DC; 274 S->setEntity(DC); 275} 276 277void Sema::PopDeclContext() { 278 assert(CurContext && "DeclContext imbalance!"); 279 280 CurContext = getContainingDC(CurContext); 281} 282 283/// EnterDeclaratorContext - Used when we must lookup names in the context 284/// of a declarator's nested name specifier. 285void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 286 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 287 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 288 CurContext = DC; 289 assert(CurContext && "No context?"); 290 S->setEntity(CurContext); 291} 292 293void Sema::ExitDeclaratorContext(Scope *S) { 294 S->setEntity(PreDeclaratorDC); 295 PreDeclaratorDC = 0; 296 297 // Reset CurContext to the nearest enclosing context. 298 while (!S->getEntity() && S->getParent()) 299 S = S->getParent(); 300 CurContext = static_cast<DeclContext*>(S->getEntity()); 301 assert(CurContext && "No context?"); 302} 303 304/// \brief Determine whether we allow overloading of the function 305/// PrevDecl with another declaration. 306/// 307/// This routine determines whether overloading is possible, not 308/// whether some new function is actually an overload. It will return 309/// true in C++ (where we can always provide overloads) or, as an 310/// extension, in C when the previous function is already an 311/// overloaded function declaration or has the "overloadable" 312/// attribute. 313static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 314 if (Context.getLangOptions().CPlusPlus) 315 return true; 316 317 if (isa<OverloadedFunctionDecl>(PrevDecl)) 318 return true; 319 320 return PrevDecl->getAttr<OverloadableAttr>() != 0; 321} 322 323/// Add this decl to the scope shadowed decl chains. 324void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 325 // Move up the scope chain until we find the nearest enclosing 326 // non-transparent context. The declaration will be introduced into this 327 // scope. 328 while (S->getEntity() && 329 ((DeclContext *)S->getEntity())->isTransparentContext()) 330 S = S->getParent(); 331 332 // Add scoped declarations into their context, so that they can be 333 // found later. Declarations without a context won't be inserted 334 // into any context. 335 if (AddToContext) 336 CurContext->addDecl(D); 337 338 // Out-of-line function and variable definitions should not be pushed into 339 // scope. 340 if ((isa<FunctionTemplateDecl>(D) && 341 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 342 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 343 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 344 return; 345 346 // If this replaces anything in the current scope, 347 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 348 IEnd = IdResolver.end(); 349 for (; I != IEnd; ++I) { 350 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 351 S->RemoveDecl(DeclPtrTy::make(*I)); 352 IdResolver.RemoveDecl(*I); 353 354 // Should only need to replace one decl. 355 break; 356 } 357 } 358 359 S->AddDecl(DeclPtrTy::make(D)); 360 IdResolver.AddDecl(D); 361} 362 363bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 364 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 365 // Look inside the overload set to determine if any of the declarations 366 // are in scope. (Possibly) build a new overload set containing only 367 // those declarations that are in scope. 368 OverloadedFunctionDecl *NewOvl = 0; 369 bool FoundInScope = false; 370 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 371 FEnd = Ovl->function_end(); 372 F != FEnd; ++F) { 373 NamedDecl *FD = F->get(); 374 if (!isDeclInScope(FD, Ctx, S)) { 375 if (!NewOvl && F != Ovl->function_begin()) { 376 NewOvl = OverloadedFunctionDecl::Create(Context, 377 F->get()->getDeclContext(), 378 F->get()->getDeclName()); 379 D = NewOvl; 380 for (OverloadedFunctionDecl::function_iterator 381 First = Ovl->function_begin(); 382 First != F; ++First) 383 NewOvl->addOverload(*First); 384 } 385 } else { 386 FoundInScope = true; 387 if (NewOvl) 388 NewOvl->addOverload(*F); 389 } 390 } 391 392 return FoundInScope; 393 } 394 395 return IdResolver.isDeclInScope(D, Ctx, Context, S); 396} 397 398static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 399 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 400 return false; 401 402 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 403 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 404 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 405 if (!RD->hasTrivialConstructor()) 406 return false; 407 if (!RD->hasTrivialDestructor()) 408 return false; 409 } 410 } 411 } 412 413 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 414 !isa<ImplicitParamDecl>(D) && 415 D->getDeclContext()->isFunctionOrMethod()); 416} 417 418void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 419 if (S->decl_empty()) return; 420 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 421 "Scope shouldn't contain decls!"); 422 423 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 424 I != E; ++I) { 425 Decl *TmpD = (*I).getAs<Decl>(); 426 assert(TmpD && "This decl didn't get pushed??"); 427 428 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 429 NamedDecl *D = cast<NamedDecl>(TmpD); 430 431 if (!D->getDeclName()) continue; 432 433 // Diagnose unused variables in this scope. 434 if (ShouldDiagnoseUnusedDecl(D)) 435 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 436 437 // Remove this name from our lexical scope. 438 IdResolver.RemoveDecl(D); 439 } 440} 441 442/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 443/// return 0 if one not found. 444ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 445 // The third "scope" argument is 0 since we aren't enabling lazy built-in 446 // creation from this context. 447 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 448 449 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 450} 451 452/// getNonFieldDeclScope - Retrieves the innermost scope, starting 453/// from S, where a non-field would be declared. This routine copes 454/// with the difference between C and C++ scoping rules in structs and 455/// unions. For example, the following code is well-formed in C but 456/// ill-formed in C++: 457/// @code 458/// struct S6 { 459/// enum { BAR } e; 460/// }; 461/// 462/// void test_S6() { 463/// struct S6 a; 464/// a.e = BAR; 465/// } 466/// @endcode 467/// For the declaration of BAR, this routine will return a different 468/// scope. The scope S will be the scope of the unnamed enumeration 469/// within S6. In C++, this routine will return the scope associated 470/// with S6, because the enumeration's scope is a transparent 471/// context but structures can contain non-field names. In C, this 472/// routine will return the translation unit scope, since the 473/// enumeration's scope is a transparent context and structures cannot 474/// contain non-field names. 475Scope *Sema::getNonFieldDeclScope(Scope *S) { 476 while (((S->getFlags() & Scope::DeclScope) == 0) || 477 (S->getEntity() && 478 ((DeclContext *)S->getEntity())->isTransparentContext()) || 479 (S->isClassScope() && !getLangOptions().CPlusPlus)) 480 S = S->getParent(); 481 return S; 482} 483 484void Sema::InitBuiltinVaListType() { 485 if (!Context.getBuiltinVaListType().isNull()) 486 return; 487 488 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 489 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 490 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 491 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 492} 493 494/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 495/// file scope. lazily create a decl for it. ForRedeclaration is true 496/// if we're creating this built-in in anticipation of redeclaring the 497/// built-in. 498NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 499 Scope *S, bool ForRedeclaration, 500 SourceLocation Loc) { 501 Builtin::ID BID = (Builtin::ID)bid; 502 503 if (Context.BuiltinInfo.hasVAListUse(BID)) 504 InitBuiltinVaListType(); 505 506 ASTContext::GetBuiltinTypeError Error; 507 QualType R = Context.GetBuiltinType(BID, Error); 508 switch (Error) { 509 case ASTContext::GE_None: 510 // Okay 511 break; 512 513 case ASTContext::GE_Missing_stdio: 514 if (ForRedeclaration) 515 Diag(Loc, diag::err_implicit_decl_requires_stdio) 516 << Context.BuiltinInfo.GetName(BID); 517 return 0; 518 519 case ASTContext::GE_Missing_setjmp: 520 if (ForRedeclaration) 521 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 522 << Context.BuiltinInfo.GetName(BID); 523 return 0; 524 } 525 526 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 527 Diag(Loc, diag::ext_implicit_lib_function_decl) 528 << Context.BuiltinInfo.GetName(BID) 529 << R; 530 if (Context.BuiltinInfo.getHeaderName(BID) && 531 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 532 != Diagnostic::Ignored) 533 Diag(Loc, diag::note_please_include_header) 534 << Context.BuiltinInfo.getHeaderName(BID) 535 << Context.BuiltinInfo.GetName(BID); 536 } 537 538 FunctionDecl *New = FunctionDecl::Create(Context, 539 Context.getTranslationUnitDecl(), 540 Loc, II, R, /*DInfo=*/0, 541 FunctionDecl::Extern, false, 542 /*hasPrototype=*/true); 543 New->setImplicit(); 544 545 // Create Decl objects for each parameter, adding them to the 546 // FunctionDecl. 547 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 548 llvm::SmallVector<ParmVarDecl*, 16> Params; 549 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 550 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 551 FT->getArgType(i), /*DInfo=*/0, 552 VarDecl::None, 0)); 553 New->setParams(Context, Params.data(), Params.size()); 554 } 555 556 AddKnownFunctionAttributes(New); 557 558 // TUScope is the translation-unit scope to insert this function into. 559 // FIXME: This is hideous. We need to teach PushOnScopeChains to 560 // relate Scopes to DeclContexts, and probably eliminate CurContext 561 // entirely, but we're not there yet. 562 DeclContext *SavedContext = CurContext; 563 CurContext = Context.getTranslationUnitDecl(); 564 PushOnScopeChains(New, TUScope); 565 CurContext = SavedContext; 566 return New; 567} 568 569/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 570/// same name and scope as a previous declaration 'Old'. Figure out 571/// how to resolve this situation, merging decls or emitting 572/// diagnostics as appropriate. If there was an error, set New to be invalid. 573/// 574void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 575 // If either decl is known invalid already, set the new one to be invalid and 576 // don't bother doing any merging checks. 577 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 578 return New->setInvalidDecl(); 579 580 // Allow multiple definitions for ObjC built-in typedefs. 581 // FIXME: Verify the underlying types are equivalent! 582 if (getLangOptions().ObjC1) { 583 const IdentifierInfo *TypeID = New->getIdentifier(); 584 switch (TypeID->getLength()) { 585 default: break; 586 case 2: 587 if (!TypeID->isStr("id")) 588 break; 589 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 590 // Install the built-in type for 'id', ignoring the current definition. 591 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 592 return; 593 case 5: 594 if (!TypeID->isStr("Class")) 595 break; 596 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 597 // Install the built-in type for 'Class', ignoring the current definition. 598 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 599 return; 600 case 3: 601 if (!TypeID->isStr("SEL")) 602 break; 603 Context.setObjCSelType(Context.getTypeDeclType(New)); 604 return; 605 case 8: 606 if (!TypeID->isStr("Protocol")) 607 break; 608 Context.setObjCProtoType(New->getUnderlyingType()); 609 return; 610 } 611 // Fall through - the typedef name was not a builtin type. 612 } 613 // Verify the old decl was also a type. 614 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 615 if (!Old) { 616 Diag(New->getLocation(), diag::err_redefinition_different_kind) 617 << New->getDeclName(); 618 if (OldD->getLocation().isValid()) 619 Diag(OldD->getLocation(), diag::note_previous_definition); 620 return New->setInvalidDecl(); 621 } 622 623 // Determine the "old" type we'll use for checking and diagnostics. 624 QualType OldType; 625 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 626 OldType = OldTypedef->getUnderlyingType(); 627 else 628 OldType = Context.getTypeDeclType(Old); 629 630 // If the typedef types are not identical, reject them in all languages and 631 // with any extensions enabled. 632 633 if (OldType != New->getUnderlyingType() && 634 Context.getCanonicalType(OldType) != 635 Context.getCanonicalType(New->getUnderlyingType())) { 636 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 637 << New->getUnderlyingType() << OldType; 638 if (Old->getLocation().isValid()) 639 Diag(Old->getLocation(), diag::note_previous_definition); 640 return New->setInvalidDecl(); 641 } 642 643 if (getLangOptions().Microsoft) 644 return; 645 646 // C++ [dcl.typedef]p2: 647 // In a given non-class scope, a typedef specifier can be used to 648 // redefine the name of any type declared in that scope to refer 649 // to the type to which it already refers. 650 if (getLangOptions().CPlusPlus) { 651 if (!isa<CXXRecordDecl>(CurContext)) 652 return; 653 Diag(New->getLocation(), diag::err_redefinition) 654 << New->getDeclName(); 655 Diag(Old->getLocation(), diag::note_previous_definition); 656 return New->setInvalidDecl(); 657 } 658 659 // If we have a redefinition of a typedef in C, emit a warning. This warning 660 // is normally mapped to an error, but can be controlled with 661 // -Wtypedef-redefinition. If either the original or the redefinition is 662 // in a system header, don't emit this for compatibility with GCC. 663 if (PP.getDiagnostics().getSuppressSystemWarnings() && 664 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 665 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 666 return; 667 668 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 669 << New->getDeclName(); 670 Diag(Old->getLocation(), diag::note_previous_definition); 671 return; 672} 673 674/// DeclhasAttr - returns true if decl Declaration already has the target 675/// attribute. 676static bool 677DeclHasAttr(const Decl *decl, const Attr *target) { 678 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 679 if (attr->getKind() == target->getKind()) 680 return true; 681 682 return false; 683} 684 685/// MergeAttributes - append attributes from the Old decl to the New one. 686static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 687 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 688 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 689 Attr *NewAttr = attr->clone(C); 690 NewAttr->setInherited(true); 691 New->addAttr(NewAttr); 692 } 693 } 694} 695 696/// Used in MergeFunctionDecl to keep track of function parameters in 697/// C. 698struct GNUCompatibleParamWarning { 699 ParmVarDecl *OldParm; 700 ParmVarDecl *NewParm; 701 QualType PromotedType; 702}; 703 704/// MergeFunctionDecl - We just parsed a function 'New' from 705/// declarator D which has the same name and scope as a previous 706/// declaration 'Old'. Figure out how to resolve this situation, 707/// merging decls or emitting diagnostics as appropriate. 708/// 709/// In C++, New and Old must be declarations that are not 710/// overloaded. Use IsOverload to determine whether New and Old are 711/// overloaded, and to select the Old declaration that New should be 712/// merged with. 713/// 714/// Returns true if there was an error, false otherwise. 715bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 716 assert(!isa<OverloadedFunctionDecl>(OldD) && 717 "Cannot merge with an overloaded function declaration"); 718 719 // Verify the old decl was also a function. 720 FunctionDecl *Old = 0; 721 if (FunctionTemplateDecl *OldFunctionTemplate 722 = dyn_cast<FunctionTemplateDecl>(OldD)) 723 Old = OldFunctionTemplate->getTemplatedDecl(); 724 else 725 Old = dyn_cast<FunctionDecl>(OldD); 726 if (!Old) { 727 Diag(New->getLocation(), diag::err_redefinition_different_kind) 728 << New->getDeclName(); 729 Diag(OldD->getLocation(), diag::note_previous_definition); 730 return true; 731 } 732 733 // Determine whether the previous declaration was a definition, 734 // implicit declaration, or a declaration. 735 diag::kind PrevDiag; 736 if (Old->isThisDeclarationADefinition()) 737 PrevDiag = diag::note_previous_definition; 738 else if (Old->isImplicit()) 739 PrevDiag = diag::note_previous_implicit_declaration; 740 else 741 PrevDiag = diag::note_previous_declaration; 742 743 QualType OldQType = Context.getCanonicalType(Old->getType()); 744 QualType NewQType = Context.getCanonicalType(New->getType()); 745 746 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 747 New->getStorageClass() == FunctionDecl::Static && 748 Old->getStorageClass() != FunctionDecl::Static) { 749 Diag(New->getLocation(), diag::err_static_non_static) 750 << New; 751 Diag(Old->getLocation(), PrevDiag); 752 return true; 753 } 754 755 if (getLangOptions().CPlusPlus) { 756 // (C++98 13.1p2): 757 // Certain function declarations cannot be overloaded: 758 // -- Function declarations that differ only in the return type 759 // cannot be overloaded. 760 QualType OldReturnType 761 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 762 QualType NewReturnType 763 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 764 if (OldReturnType != NewReturnType) { 765 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 766 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 767 return true; 768 } 769 770 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 771 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 772 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 773 NewMethod->getLexicalDeclContext()->isRecord()) { 774 // -- Member function declarations with the same name and the 775 // same parameter types cannot be overloaded if any of them 776 // is a static member function declaration. 777 if (OldMethod->isStatic() || NewMethod->isStatic()) { 778 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 779 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 780 return true; 781 } 782 783 // C++ [class.mem]p1: 784 // [...] A member shall not be declared twice in the 785 // member-specification, except that a nested class or member 786 // class template can be declared and then later defined. 787 unsigned NewDiag; 788 if (isa<CXXConstructorDecl>(OldMethod)) 789 NewDiag = diag::err_constructor_redeclared; 790 else if (isa<CXXDestructorDecl>(NewMethod)) 791 NewDiag = diag::err_destructor_redeclared; 792 else if (isa<CXXConversionDecl>(NewMethod)) 793 NewDiag = diag::err_conv_function_redeclared; 794 else 795 NewDiag = diag::err_member_redeclared; 796 797 Diag(New->getLocation(), NewDiag); 798 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 799 } 800 801 // (C++98 8.3.5p3): 802 // All declarations for a function shall agree exactly in both the 803 // return type and the parameter-type-list. 804 if (OldQType == NewQType) 805 return MergeCompatibleFunctionDecls(New, Old); 806 807 // Fall through for conflicting redeclarations and redefinitions. 808 } 809 810 // C: Function types need to be compatible, not identical. This handles 811 // duplicate function decls like "void f(int); void f(enum X);" properly. 812 if (!getLangOptions().CPlusPlus && 813 Context.typesAreCompatible(OldQType, NewQType)) { 814 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 815 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 816 const FunctionProtoType *OldProto = 0; 817 if (isa<FunctionNoProtoType>(NewFuncType) && 818 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 819 // The old declaration provided a function prototype, but the 820 // new declaration does not. Merge in the prototype. 821 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 822 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 823 OldProto->arg_type_end()); 824 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 825 ParamTypes.data(), ParamTypes.size(), 826 OldProto->isVariadic(), 827 OldProto->getTypeQuals()); 828 New->setType(NewQType); 829 New->setHasInheritedPrototype(); 830 831 // Synthesize a parameter for each argument type. 832 llvm::SmallVector<ParmVarDecl*, 16> Params; 833 for (FunctionProtoType::arg_type_iterator 834 ParamType = OldProto->arg_type_begin(), 835 ParamEnd = OldProto->arg_type_end(); 836 ParamType != ParamEnd; ++ParamType) { 837 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 838 SourceLocation(), 0, 839 *ParamType, /*DInfo=*/0, 840 VarDecl::None, 0); 841 Param->setImplicit(); 842 Params.push_back(Param); 843 } 844 845 New->setParams(Context, Params.data(), Params.size()); 846 } 847 848 return MergeCompatibleFunctionDecls(New, Old); 849 } 850 851 // GNU C permits a K&R definition to follow a prototype declaration 852 // if the declared types of the parameters in the K&R definition 853 // match the types in the prototype declaration, even when the 854 // promoted types of the parameters from the K&R definition differ 855 // from the types in the prototype. GCC then keeps the types from 856 // the prototype. 857 // 858 // If a variadic prototype is followed by a non-variadic K&R definition, 859 // the K&R definition becomes variadic. This is sort of an edge case, but 860 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 861 // C99 6.9.1p8. 862 if (!getLangOptions().CPlusPlus && 863 Old->hasPrototype() && !New->hasPrototype() && 864 New->getType()->getAs<FunctionProtoType>() && 865 Old->getNumParams() == New->getNumParams()) { 866 llvm::SmallVector<QualType, 16> ArgTypes; 867 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 868 const FunctionProtoType *OldProto 869 = Old->getType()->getAs<FunctionProtoType>(); 870 const FunctionProtoType *NewProto 871 = New->getType()->getAs<FunctionProtoType>(); 872 873 // Determine whether this is the GNU C extension. 874 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 875 NewProto->getResultType()); 876 bool LooseCompatible = !MergedReturn.isNull(); 877 for (unsigned Idx = 0, End = Old->getNumParams(); 878 LooseCompatible && Idx != End; ++Idx) { 879 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 880 ParmVarDecl *NewParm = New->getParamDecl(Idx); 881 if (Context.typesAreCompatible(OldParm->getType(), 882 NewProto->getArgType(Idx))) { 883 ArgTypes.push_back(NewParm->getType()); 884 } else if (Context.typesAreCompatible(OldParm->getType(), 885 NewParm->getType())) { 886 GNUCompatibleParamWarning Warn 887 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 888 Warnings.push_back(Warn); 889 ArgTypes.push_back(NewParm->getType()); 890 } else 891 LooseCompatible = false; 892 } 893 894 if (LooseCompatible) { 895 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 896 Diag(Warnings[Warn].NewParm->getLocation(), 897 diag::ext_param_promoted_not_compatible_with_prototype) 898 << Warnings[Warn].PromotedType 899 << Warnings[Warn].OldParm->getType(); 900 Diag(Warnings[Warn].OldParm->getLocation(), 901 diag::note_previous_declaration); 902 } 903 904 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 905 ArgTypes.size(), 906 OldProto->isVariadic(), 0)); 907 return MergeCompatibleFunctionDecls(New, Old); 908 } 909 910 // Fall through to diagnose conflicting types. 911 } 912 913 // A function that has already been declared has been redeclared or defined 914 // with a different type- show appropriate diagnostic 915 if (unsigned BuiltinID = Old->getBuiltinID()) { 916 // The user has declared a builtin function with an incompatible 917 // signature. 918 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 919 // The function the user is redeclaring is a library-defined 920 // function like 'malloc' or 'printf'. Warn about the 921 // redeclaration, then pretend that we don't know about this 922 // library built-in. 923 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 924 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 925 << Old << Old->getType(); 926 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 927 Old->setInvalidDecl(); 928 return false; 929 } 930 931 PrevDiag = diag::note_previous_builtin_declaration; 932 } 933 934 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 935 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 936 return true; 937} 938 939/// \brief Completes the merge of two function declarations that are 940/// known to be compatible. 941/// 942/// This routine handles the merging of attributes and other 943/// properties of function declarations form the old declaration to 944/// the new declaration, once we know that New is in fact a 945/// redeclaration of Old. 946/// 947/// \returns false 948bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 949 // Merge the attributes 950 MergeAttributes(New, Old, Context); 951 952 // Merge the storage class. 953 if (Old->getStorageClass() != FunctionDecl::Extern && 954 Old->getStorageClass() != FunctionDecl::None) 955 New->setStorageClass(Old->getStorageClass()); 956 957 // Merge "pure" flag. 958 if (Old->isPure()) 959 New->setPure(); 960 961 // Merge the "deleted" flag. 962 if (Old->isDeleted()) 963 New->setDeleted(); 964 965 if (getLangOptions().CPlusPlus) 966 return MergeCXXFunctionDecl(New, Old); 967 968 return false; 969} 970 971/// MergeVarDecl - We just parsed a variable 'New' which has the same name 972/// and scope as a previous declaration 'Old'. Figure out how to resolve this 973/// situation, merging decls or emitting diagnostics as appropriate. 974/// 975/// Tentative definition rules (C99 6.9.2p2) are checked by 976/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 977/// definitions here, since the initializer hasn't been attached. 978/// 979void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 980 // If either decl is invalid, make sure the new one is marked invalid and 981 // don't do any other checking. 982 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 983 return New->setInvalidDecl(); 984 985 // Verify the old decl was also a variable. 986 VarDecl *Old = dyn_cast<VarDecl>(OldD); 987 if (!Old) { 988 Diag(New->getLocation(), diag::err_redefinition_different_kind) 989 << New->getDeclName(); 990 Diag(OldD->getLocation(), diag::note_previous_definition); 991 return New->setInvalidDecl(); 992 } 993 994 MergeAttributes(New, Old, Context); 995 996 // Merge the types 997 QualType MergedT; 998 if (getLangOptions().CPlusPlus) { 999 if (Context.hasSameType(New->getType(), Old->getType())) 1000 MergedT = New->getType(); 1001 // C++ [basic.types]p7: 1002 // [...] The declared type of an array object might be an array of 1003 // unknown size and therefore be incomplete at one point in a 1004 // translation unit and complete later on; [...] 1005 else if (Old->getType()->isIncompleteArrayType() && 1006 New->getType()->isArrayType()) { 1007 CanQual<ArrayType> OldArray 1008 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1009 CanQual<ArrayType> NewArray 1010 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1011 if (OldArray->getElementType() == NewArray->getElementType()) 1012 MergedT = New->getType(); 1013 } 1014 } else { 1015 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1016 } 1017 if (MergedT.isNull()) { 1018 Diag(New->getLocation(), diag::err_redefinition_different_type) 1019 << New->getDeclName(); 1020 Diag(Old->getLocation(), diag::note_previous_definition); 1021 return New->setInvalidDecl(); 1022 } 1023 New->setType(MergedT); 1024 1025 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1026 if (New->getStorageClass() == VarDecl::Static && 1027 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1028 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1029 Diag(Old->getLocation(), diag::note_previous_definition); 1030 return New->setInvalidDecl(); 1031 } 1032 // C99 6.2.2p4: 1033 // For an identifier declared with the storage-class specifier 1034 // extern in a scope in which a prior declaration of that 1035 // identifier is visible,23) if the prior declaration specifies 1036 // internal or external linkage, the linkage of the identifier at 1037 // the later declaration is the same as the linkage specified at 1038 // the prior declaration. If no prior declaration is visible, or 1039 // if the prior declaration specifies no linkage, then the 1040 // identifier has external linkage. 1041 if (New->hasExternalStorage() && Old->hasLinkage()) 1042 /* Okay */; 1043 else if (New->getStorageClass() != VarDecl::Static && 1044 Old->getStorageClass() == VarDecl::Static) { 1045 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1046 Diag(Old->getLocation(), diag::note_previous_definition); 1047 return New->setInvalidDecl(); 1048 } 1049 1050 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1051 1052 // FIXME: The test for external storage here seems wrong? We still 1053 // need to check for mismatches. 1054 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1055 // Don't complain about out-of-line definitions of static members. 1056 !(Old->getLexicalDeclContext()->isRecord() && 1057 !New->getLexicalDeclContext()->isRecord())) { 1058 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1059 Diag(Old->getLocation(), diag::note_previous_definition); 1060 return New->setInvalidDecl(); 1061 } 1062 1063 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1064 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1065 Diag(Old->getLocation(), diag::note_previous_definition); 1066 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1067 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1068 Diag(Old->getLocation(), diag::note_previous_definition); 1069 } 1070 1071 // Keep a chain of previous declarations. 1072 New->setPreviousDeclaration(Old); 1073} 1074 1075/// CheckFallThrough - Check that we don't fall off the end of a 1076/// Statement that should return a value. 1077/// 1078/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1079/// MaybeFallThrough iff we might or might not fall off the end, 1080/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1081/// return. We assume NeverFallThrough iff we never fall off the end of the 1082/// statement but we may return. We assume that functions not marked noreturn 1083/// will return. 1084Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1085 // FIXME: Eventually share this CFG object when we have other warnings based 1086 // of the CFG. This can be done using AnalysisContext. 1087 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1088 1089 // FIXME: They should never return 0, fix that, delete this code. 1090 if (cfg == 0) 1091 // FIXME: This should be NeverFallThrough 1092 return NeverFallThroughOrReturn; 1093 // The CFG leaves in dead things, and we don't want to dead code paths to 1094 // confuse us, so we mark all live things first. 1095 std::queue<CFGBlock*> workq; 1096 llvm::BitVector live(cfg->getNumBlockIDs()); 1097 // Prep work queue 1098 workq.push(&cfg->getEntry()); 1099 // Solve 1100 while (!workq.empty()) { 1101 CFGBlock *item = workq.front(); 1102 workq.pop(); 1103 live.set(item->getBlockID()); 1104 for (CFGBlock::succ_iterator I=item->succ_begin(), 1105 E=item->succ_end(); 1106 I != E; 1107 ++I) { 1108 if ((*I) && !live[(*I)->getBlockID()]) { 1109 live.set((*I)->getBlockID()); 1110 workq.push(*I); 1111 } 1112 } 1113 } 1114 1115 // Now we know what is live, we check the live precessors of the exit block 1116 // and look for fall through paths, being careful to ignore normal returns, 1117 // and exceptional paths. 1118 bool HasLiveReturn = false; 1119 bool HasFakeEdge = false; 1120 bool HasPlainEdge = false; 1121 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1122 E = cfg->getExit().pred_end(); 1123 I != E; 1124 ++I) { 1125 CFGBlock& B = **I; 1126 if (!live[B.getBlockID()]) 1127 continue; 1128 if (B.size() == 0) { 1129 // A labeled empty statement, or the entry block... 1130 HasPlainEdge = true; 1131 continue; 1132 } 1133 Stmt *S = B[B.size()-1]; 1134 if (isa<ReturnStmt>(S)) { 1135 HasLiveReturn = true; 1136 continue; 1137 } 1138 if (isa<ObjCAtThrowStmt>(S)) { 1139 HasFakeEdge = true; 1140 continue; 1141 } 1142 if (isa<CXXThrowExpr>(S)) { 1143 HasFakeEdge = true; 1144 continue; 1145 } 1146 bool NoReturnEdge = false; 1147 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1148 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1149 if (CEE->getType().getNoReturnAttr()) { 1150 NoReturnEdge = true; 1151 HasFakeEdge = true; 1152 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1153 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1154 if (FD->hasAttr<NoReturnAttr>()) { 1155 NoReturnEdge = true; 1156 HasFakeEdge = true; 1157 } 1158 } 1159 } 1160 } 1161 // FIXME: Add noreturn message sends. 1162 if (NoReturnEdge == false) 1163 HasPlainEdge = true; 1164 } 1165 if (!HasPlainEdge) { 1166 if (HasLiveReturn) 1167 return NeverFallThrough; 1168 return NeverFallThroughOrReturn; 1169 } 1170 if (HasFakeEdge || HasLiveReturn) 1171 return MaybeFallThrough; 1172 // This says AlwaysFallThrough for calls to functions that are not marked 1173 // noreturn, that don't return. If people would like this warning to be more 1174 // accurate, such functions should be marked as noreturn. 1175 return AlwaysFallThrough; 1176} 1177 1178/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1179/// function that should return a value. Check that we don't fall off the end 1180/// of a noreturn function. We assume that functions and blocks not marked 1181/// noreturn will return. 1182void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1183 // FIXME: Would be nice if we had a better way to control cascading errors, 1184 // but for now, avoid them. The problem is that when Parse sees: 1185 // int foo() { return a; } 1186 // The return is eaten and the Sema code sees just: 1187 // int foo() { } 1188 // which this code would then warn about. 1189 if (getDiagnostics().hasErrorOccurred()) 1190 return; 1191 1192 bool ReturnsVoid = false; 1193 bool HasNoReturn = false; 1194 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1195 // If the result type of the function is a dependent type, we don't know 1196 // whether it will be void or not, so don't 1197 if (FD->getResultType()->isDependentType()) 1198 return; 1199 if (FD->getResultType()->isVoidType()) 1200 ReturnsVoid = true; 1201 if (FD->hasAttr<NoReturnAttr>()) 1202 HasNoReturn = true; 1203 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1204 if (MD->getResultType()->isVoidType()) 1205 ReturnsVoid = true; 1206 if (MD->hasAttr<NoReturnAttr>()) 1207 HasNoReturn = true; 1208 } 1209 1210 // Short circuit for compilation speed. 1211 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1212 == Diagnostic::Ignored || ReturnsVoid) 1213 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1214 == Diagnostic::Ignored || !HasNoReturn) 1215 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1216 == Diagnostic::Ignored || !ReturnsVoid)) 1217 return; 1218 // FIXME: Function try block 1219 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1220 switch (CheckFallThrough(Body)) { 1221 case MaybeFallThrough: 1222 if (HasNoReturn) 1223 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1224 else if (!ReturnsVoid) 1225 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1226 break; 1227 case AlwaysFallThrough: 1228 if (HasNoReturn) 1229 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1230 else if (!ReturnsVoid) 1231 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1232 break; 1233 case NeverFallThroughOrReturn: 1234 if (ReturnsVoid && !HasNoReturn) 1235 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1236 break; 1237 case NeverFallThrough: 1238 break; 1239 } 1240 } 1241} 1242 1243/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1244/// that should return a value. Check that we don't fall off the end of a 1245/// noreturn block. We assume that functions and blocks not marked noreturn 1246/// will return. 1247void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1248 // FIXME: Would be nice if we had a better way to control cascading errors, 1249 // but for now, avoid them. The problem is that when Parse sees: 1250 // int foo() { return a; } 1251 // The return is eaten and the Sema code sees just: 1252 // int foo() { } 1253 // which this code would then warn about. 1254 if (getDiagnostics().hasErrorOccurred()) 1255 return; 1256 bool ReturnsVoid = false; 1257 bool HasNoReturn = false; 1258 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1259 if (FT->getResultType()->isVoidType()) 1260 ReturnsVoid = true; 1261 if (FT->getNoReturnAttr()) 1262 HasNoReturn = true; 1263 } 1264 1265 // Short circuit for compilation speed. 1266 if (ReturnsVoid 1267 && !HasNoReturn 1268 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1269 == Diagnostic::Ignored || !ReturnsVoid)) 1270 return; 1271 // FIXME: Funtion try block 1272 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1273 switch (CheckFallThrough(Body)) { 1274 case MaybeFallThrough: 1275 if (HasNoReturn) 1276 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1277 else if (!ReturnsVoid) 1278 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1279 break; 1280 case AlwaysFallThrough: 1281 if (HasNoReturn) 1282 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1283 else if (!ReturnsVoid) 1284 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1285 break; 1286 case NeverFallThroughOrReturn: 1287 if (ReturnsVoid) 1288 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1289 break; 1290 case NeverFallThrough: 1291 break; 1292 } 1293 } 1294} 1295 1296/// CheckParmsForFunctionDef - Check that the parameters of the given 1297/// function are appropriate for the definition of a function. This 1298/// takes care of any checks that cannot be performed on the 1299/// declaration itself, e.g., that the types of each of the function 1300/// parameters are complete. 1301bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1302 bool HasInvalidParm = false; 1303 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1304 ParmVarDecl *Param = FD->getParamDecl(p); 1305 1306 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1307 // function declarator that is part of a function definition of 1308 // that function shall not have incomplete type. 1309 // 1310 // This is also C++ [dcl.fct]p6. 1311 if (!Param->isInvalidDecl() && 1312 RequireCompleteType(Param->getLocation(), Param->getType(), 1313 diag::err_typecheck_decl_incomplete_type)) { 1314 Param->setInvalidDecl(); 1315 HasInvalidParm = true; 1316 } 1317 1318 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1319 // declaration of each parameter shall include an identifier. 1320 if (Param->getIdentifier() == 0 && 1321 !Param->isImplicit() && 1322 !getLangOptions().CPlusPlus) 1323 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1324 } 1325 1326 return HasInvalidParm; 1327} 1328 1329/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1330/// no declarator (e.g. "struct foo;") is parsed. 1331Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1332 // FIXME: Error on auto/register at file scope 1333 // FIXME: Error on inline/virtual/explicit 1334 // FIXME: Error on invalid restrict 1335 // FIXME: Warn on useless __thread 1336 // FIXME: Warn on useless const/volatile 1337 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1338 // FIXME: Warn on useless attributes 1339 Decl *TagD = 0; 1340 TagDecl *Tag = 0; 1341 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1342 DS.getTypeSpecType() == DeclSpec::TST_struct || 1343 DS.getTypeSpecType() == DeclSpec::TST_union || 1344 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1345 TagD = static_cast<Decl *>(DS.getTypeRep()); 1346 1347 if (!TagD) // We probably had an error 1348 return DeclPtrTy(); 1349 1350 // Note that the above type specs guarantee that the 1351 // type rep is a Decl, whereas in many of the others 1352 // it's a Type. 1353 Tag = dyn_cast<TagDecl>(TagD); 1354 } 1355 1356 if (DS.isFriendSpecified()) { 1357 // If we're dealing with a class template decl, assume that the 1358 // template routines are handling it. 1359 if (TagD && isa<ClassTemplateDecl>(TagD)) 1360 return DeclPtrTy(); 1361 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1362 } 1363 1364 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1365 // If there are attributes in the DeclSpec, apply them to the record. 1366 if (const AttributeList *AL = DS.getAttributes()) 1367 ProcessDeclAttributeList(S, Record, AL); 1368 1369 if (!Record->getDeclName() && Record->isDefinition() && 1370 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1371 if (getLangOptions().CPlusPlus || 1372 Record->getDeclContext()->isRecord()) 1373 return BuildAnonymousStructOrUnion(S, DS, Record); 1374 1375 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1376 << DS.getSourceRange(); 1377 } 1378 1379 // Microsoft allows unnamed struct/union fields. Don't complain 1380 // about them. 1381 // FIXME: Should we support Microsoft's extensions in this area? 1382 if (Record->getDeclName() && getLangOptions().Microsoft) 1383 return DeclPtrTy::make(Tag); 1384 } 1385 1386 if (!DS.isMissingDeclaratorOk() && 1387 DS.getTypeSpecType() != DeclSpec::TST_error) { 1388 // Warn about typedefs of enums without names, since this is an 1389 // extension in both Microsoft an GNU. 1390 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1391 Tag && isa<EnumDecl>(Tag)) { 1392 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1393 << DS.getSourceRange(); 1394 return DeclPtrTy::make(Tag); 1395 } 1396 1397 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1398 << DS.getSourceRange(); 1399 return DeclPtrTy(); 1400 } 1401 1402 return DeclPtrTy::make(Tag); 1403} 1404 1405/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1406/// anonymous struct or union AnonRecord into the owning context Owner 1407/// and scope S. This routine will be invoked just after we realize 1408/// that an unnamed union or struct is actually an anonymous union or 1409/// struct, e.g., 1410/// 1411/// @code 1412/// union { 1413/// int i; 1414/// float f; 1415/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1416/// // f into the surrounding scope.x 1417/// @endcode 1418/// 1419/// This routine is recursive, injecting the names of nested anonymous 1420/// structs/unions into the owning context and scope as well. 1421bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1422 RecordDecl *AnonRecord) { 1423 bool Invalid = false; 1424 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1425 FEnd = AnonRecord->field_end(); 1426 F != FEnd; ++F) { 1427 if ((*F)->getDeclName()) { 1428 LookupResult R(*this, (*F)->getDeclName(), SourceLocation(), 1429 LookupOrdinaryName, LookupResult::ForRedeclaration); 1430 LookupQualifiedName(R, Owner); 1431 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1432 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1433 // C++ [class.union]p2: 1434 // The names of the members of an anonymous union shall be 1435 // distinct from the names of any other entity in the 1436 // scope in which the anonymous union is declared. 1437 unsigned diagKind 1438 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1439 : diag::err_anonymous_struct_member_redecl; 1440 Diag((*F)->getLocation(), diagKind) 1441 << (*F)->getDeclName(); 1442 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1443 Invalid = true; 1444 } else { 1445 // C++ [class.union]p2: 1446 // For the purpose of name lookup, after the anonymous union 1447 // definition, the members of the anonymous union are 1448 // considered to have been defined in the scope in which the 1449 // anonymous union is declared. 1450 Owner->makeDeclVisibleInContext(*F); 1451 S->AddDecl(DeclPtrTy::make(*F)); 1452 IdResolver.AddDecl(*F); 1453 } 1454 } else if (const RecordType *InnerRecordType 1455 = (*F)->getType()->getAs<RecordType>()) { 1456 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1457 if (InnerRecord->isAnonymousStructOrUnion()) 1458 Invalid = Invalid || 1459 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1460 } 1461 } 1462 1463 return Invalid; 1464} 1465 1466/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1467/// anonymous structure or union. Anonymous unions are a C++ feature 1468/// (C++ [class.union]) and a GNU C extension; anonymous structures 1469/// are a GNU C and GNU C++ extension. 1470Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1471 RecordDecl *Record) { 1472 DeclContext *Owner = Record->getDeclContext(); 1473 1474 // Diagnose whether this anonymous struct/union is an extension. 1475 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1476 Diag(Record->getLocation(), diag::ext_anonymous_union); 1477 else if (!Record->isUnion()) 1478 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1479 1480 // C and C++ require different kinds of checks for anonymous 1481 // structs/unions. 1482 bool Invalid = false; 1483 if (getLangOptions().CPlusPlus) { 1484 const char* PrevSpec = 0; 1485 unsigned DiagID; 1486 // C++ [class.union]p3: 1487 // Anonymous unions declared in a named namespace or in the 1488 // global namespace shall be declared static. 1489 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1490 (isa<TranslationUnitDecl>(Owner) || 1491 (isa<NamespaceDecl>(Owner) && 1492 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1493 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1494 Invalid = true; 1495 1496 // Recover by adding 'static'. 1497 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1498 PrevSpec, DiagID); 1499 } 1500 // C++ [class.union]p3: 1501 // A storage class is not allowed in a declaration of an 1502 // anonymous union in a class scope. 1503 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1504 isa<RecordDecl>(Owner)) { 1505 Diag(DS.getStorageClassSpecLoc(), 1506 diag::err_anonymous_union_with_storage_spec); 1507 Invalid = true; 1508 1509 // Recover by removing the storage specifier. 1510 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1511 PrevSpec, DiagID); 1512 } 1513 1514 // C++ [class.union]p2: 1515 // The member-specification of an anonymous union shall only 1516 // define non-static data members. [Note: nested types and 1517 // functions cannot be declared within an anonymous union. ] 1518 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1519 MemEnd = Record->decls_end(); 1520 Mem != MemEnd; ++Mem) { 1521 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1522 // C++ [class.union]p3: 1523 // An anonymous union shall not have private or protected 1524 // members (clause 11). 1525 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1526 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1527 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1528 Invalid = true; 1529 } 1530 } else if ((*Mem)->isImplicit()) { 1531 // Any implicit members are fine. 1532 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1533 // This is a type that showed up in an 1534 // elaborated-type-specifier inside the anonymous struct or 1535 // union, but which actually declares a type outside of the 1536 // anonymous struct or union. It's okay. 1537 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1538 if (!MemRecord->isAnonymousStructOrUnion() && 1539 MemRecord->getDeclName()) { 1540 // This is a nested type declaration. 1541 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1542 << (int)Record->isUnion(); 1543 Invalid = true; 1544 } 1545 } else { 1546 // We have something that isn't a non-static data 1547 // member. Complain about it. 1548 unsigned DK = diag::err_anonymous_record_bad_member; 1549 if (isa<TypeDecl>(*Mem)) 1550 DK = diag::err_anonymous_record_with_type; 1551 else if (isa<FunctionDecl>(*Mem)) 1552 DK = diag::err_anonymous_record_with_function; 1553 else if (isa<VarDecl>(*Mem)) 1554 DK = diag::err_anonymous_record_with_static; 1555 Diag((*Mem)->getLocation(), DK) 1556 << (int)Record->isUnion(); 1557 Invalid = true; 1558 } 1559 } 1560 } 1561 1562 if (!Record->isUnion() && !Owner->isRecord()) { 1563 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1564 << (int)getLangOptions().CPlusPlus; 1565 Invalid = true; 1566 } 1567 1568 // Mock up a declarator. 1569 Declarator Dc(DS, Declarator::TypeNameContext); 1570 DeclaratorInfo *DInfo = 0; 1571 GetTypeForDeclarator(Dc, S, &DInfo); 1572 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1573 1574 // Create a declaration for this anonymous struct/union. 1575 NamedDecl *Anon = 0; 1576 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1577 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1578 /*IdentifierInfo=*/0, 1579 Context.getTypeDeclType(Record), 1580 DInfo, 1581 /*BitWidth=*/0, /*Mutable=*/false); 1582 Anon->setAccess(AS_public); 1583 if (getLangOptions().CPlusPlus) 1584 FieldCollector->Add(cast<FieldDecl>(Anon)); 1585 } else { 1586 VarDecl::StorageClass SC; 1587 switch (DS.getStorageClassSpec()) { 1588 default: assert(0 && "Unknown storage class!"); 1589 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1590 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1591 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1592 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1593 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1594 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1595 case DeclSpec::SCS_mutable: 1596 // mutable can only appear on non-static class members, so it's always 1597 // an error here 1598 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1599 Invalid = true; 1600 SC = VarDecl::None; 1601 break; 1602 } 1603 1604 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1605 /*IdentifierInfo=*/0, 1606 Context.getTypeDeclType(Record), 1607 DInfo, 1608 SC); 1609 } 1610 Anon->setImplicit(); 1611 1612 // Add the anonymous struct/union object to the current 1613 // context. We'll be referencing this object when we refer to one of 1614 // its members. 1615 Owner->addDecl(Anon); 1616 1617 // Inject the members of the anonymous struct/union into the owning 1618 // context and into the identifier resolver chain for name lookup 1619 // purposes. 1620 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1621 Invalid = true; 1622 1623 // Mark this as an anonymous struct/union type. Note that we do not 1624 // do this until after we have already checked and injected the 1625 // members of this anonymous struct/union type, because otherwise 1626 // the members could be injected twice: once by DeclContext when it 1627 // builds its lookup table, and once by 1628 // InjectAnonymousStructOrUnionMembers. 1629 Record->setAnonymousStructOrUnion(true); 1630 1631 if (Invalid) 1632 Anon->setInvalidDecl(); 1633 1634 return DeclPtrTy::make(Anon); 1635} 1636 1637 1638/// GetNameForDeclarator - Determine the full declaration name for the 1639/// given Declarator. 1640DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1641 return GetNameFromUnqualifiedId(D.getName()); 1642} 1643 1644/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1645DeclarationName Sema::GetNameFromUnqualifiedId(UnqualifiedId &Name) { 1646 switch (Name.getKind()) { 1647 case UnqualifiedId::IK_Identifier: 1648 return DeclarationName(Name.Identifier); 1649 1650 case UnqualifiedId::IK_OperatorFunctionId: 1651 return Context.DeclarationNames.getCXXOperatorName( 1652 Name.OperatorFunctionId.Operator); 1653 1654 case UnqualifiedId::IK_ConversionFunctionId: { 1655 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1656 if (Ty.isNull()) 1657 return DeclarationName(); 1658 1659 return Context.DeclarationNames.getCXXConversionFunctionName( 1660 Context.getCanonicalType(Ty)); 1661 } 1662 1663 case UnqualifiedId::IK_ConstructorName: { 1664 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1665 if (Ty.isNull()) 1666 return DeclarationName(); 1667 1668 return Context.DeclarationNames.getCXXConstructorName( 1669 Context.getCanonicalType(Ty)); 1670 } 1671 1672 case UnqualifiedId::IK_DestructorName: { 1673 QualType Ty = GetTypeFromParser(Name.DestructorName); 1674 if (Ty.isNull()) 1675 return DeclarationName(); 1676 1677 return Context.DeclarationNames.getCXXDestructorName( 1678 Context.getCanonicalType(Ty)); 1679 } 1680 1681 case UnqualifiedId::IK_TemplateId: { 1682 TemplateName TName 1683 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1684 if (TemplateDecl *Template = TName.getAsTemplateDecl()) 1685 return Template->getDeclName(); 1686 if (OverloadedFunctionDecl *Ovl = TName.getAsOverloadedFunctionDecl()) 1687 return Ovl->getDeclName(); 1688 1689 return DeclarationName(); 1690 } 1691 } 1692 1693 assert(false && "Unknown name kind"); 1694 return DeclarationName(); 1695} 1696 1697/// isNearlyMatchingFunction - Determine whether the C++ functions 1698/// Declaration and Definition are "nearly" matching. This heuristic 1699/// is used to improve diagnostics in the case where an out-of-line 1700/// function definition doesn't match any declaration within 1701/// the class or namespace. 1702static bool isNearlyMatchingFunction(ASTContext &Context, 1703 FunctionDecl *Declaration, 1704 FunctionDecl *Definition) { 1705 if (Declaration->param_size() != Definition->param_size()) 1706 return false; 1707 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1708 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1709 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1710 1711 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1712 DefParamTy.getNonReferenceType())) 1713 return false; 1714 } 1715 1716 return true; 1717} 1718 1719Sema::DeclPtrTy 1720Sema::HandleDeclarator(Scope *S, Declarator &D, 1721 MultiTemplateParamsArg TemplateParamLists, 1722 bool IsFunctionDefinition) { 1723 DeclarationName Name = GetNameForDeclarator(D); 1724 1725 // All of these full declarators require an identifier. If it doesn't have 1726 // one, the ParsedFreeStandingDeclSpec action should be used. 1727 if (!Name) { 1728 if (!D.isInvalidType()) // Reject this if we think it is valid. 1729 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1730 diag::err_declarator_need_ident) 1731 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1732 return DeclPtrTy(); 1733 } 1734 1735 // The scope passed in may not be a decl scope. Zip up the scope tree until 1736 // we find one that is. 1737 while ((S->getFlags() & Scope::DeclScope) == 0 || 1738 (S->getFlags() & Scope::TemplateParamScope) != 0) 1739 S = S->getParent(); 1740 1741 // If this is an out-of-line definition of a member of a class template 1742 // or class template partial specialization, we may need to rebuild the 1743 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1744 // for more information. 1745 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1746 // handle expressions properly. 1747 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1748 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1749 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1750 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1751 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1752 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1753 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1754 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1755 // FIXME: Preserve type source info. 1756 QualType T = GetTypeFromParser(DS.getTypeRep()); 1757 EnterDeclaratorContext(S, DC); 1758 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1759 ExitDeclaratorContext(S); 1760 if (T.isNull()) 1761 return DeclPtrTy(); 1762 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1763 } 1764 } 1765 1766 DeclContext *DC; 1767 NamedDecl *PrevDecl; 1768 NamedDecl *New; 1769 1770 DeclaratorInfo *DInfo = 0; 1771 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1772 1773 // See if this is a redefinition of a variable in the same scope. 1774 if (D.getCXXScopeSpec().isInvalid()) { 1775 DC = CurContext; 1776 PrevDecl = 0; 1777 D.setInvalidType(); 1778 } else if (!D.getCXXScopeSpec().isSet()) { 1779 LookupNameKind NameKind = LookupOrdinaryName; 1780 1781 // If the declaration we're planning to build will be a function 1782 // or object with linkage, then look for another declaration with 1783 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1784 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1785 /* Do nothing*/; 1786 else if (R->isFunctionType()) { 1787 if (CurContext->isFunctionOrMethod() || 1788 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1789 NameKind = LookupRedeclarationWithLinkage; 1790 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1791 NameKind = LookupRedeclarationWithLinkage; 1792 else if (CurContext->getLookupContext()->isTranslationUnit() && 1793 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1794 NameKind = LookupRedeclarationWithLinkage; 1795 1796 DC = CurContext; 1797 LookupResult R(*this, Name, D.getIdentifierLoc(), NameKind, 1798 LookupResult::ForRedeclaration); 1799 1800 LookupName(R, S, NameKind == LookupRedeclarationWithLinkage); 1801 PrevDecl = R.getAsSingleDecl(Context); 1802 } else { // Something like "int foo::x;" 1803 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1804 1805 if (!DC) { 1806 // If we could not compute the declaration context, it's because the 1807 // declaration context is dependent but does not refer to a class, 1808 // class template, or class template partial specialization. Complain 1809 // and return early, to avoid the coming semantic disaster. 1810 Diag(D.getIdentifierLoc(), 1811 diag::err_template_qualified_declarator_no_match) 1812 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1813 << D.getCXXScopeSpec().getRange(); 1814 return DeclPtrTy(); 1815 } 1816 1817 if (!DC->isDependentContext() && 1818 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1819 return DeclPtrTy(); 1820 1821 LookupResult Res(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1822 LookupResult::ForRedeclaration); 1823 LookupQualifiedName(Res, DC); 1824 PrevDecl = Res.getAsSingleDecl(Context); 1825 1826 // C++ 7.3.1.2p2: 1827 // Members (including explicit specializations of templates) of a named 1828 // namespace can also be defined outside that namespace by explicit 1829 // qualification of the name being defined, provided that the entity being 1830 // defined was already declared in the namespace and the definition appears 1831 // after the point of declaration in a namespace that encloses the 1832 // declarations namespace. 1833 // 1834 // Note that we only check the context at this point. We don't yet 1835 // have enough information to make sure that PrevDecl is actually 1836 // the declaration we want to match. For example, given: 1837 // 1838 // class X { 1839 // void f(); 1840 // void f(float); 1841 // }; 1842 // 1843 // void X::f(int) { } // ill-formed 1844 // 1845 // In this case, PrevDecl will point to the overload set 1846 // containing the two f's declared in X, but neither of them 1847 // matches. 1848 1849 // First check whether we named the global scope. 1850 if (isa<TranslationUnitDecl>(DC)) { 1851 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1852 << Name << D.getCXXScopeSpec().getRange(); 1853 } else { 1854 DeclContext *Cur = CurContext; 1855 while (isa<LinkageSpecDecl>(Cur)) 1856 Cur = Cur->getParent(); 1857 if (!Cur->Encloses(DC)) { 1858 // The qualifying scope doesn't enclose the original declaration. 1859 // Emit diagnostic based on current scope. 1860 SourceLocation L = D.getIdentifierLoc(); 1861 SourceRange R = D.getCXXScopeSpec().getRange(); 1862 if (isa<FunctionDecl>(Cur)) 1863 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1864 else 1865 Diag(L, diag::err_invalid_declarator_scope) 1866 << Name << cast<NamedDecl>(DC) << R; 1867 D.setInvalidType(); 1868 } 1869 } 1870 } 1871 1872 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1873 // Maybe we will complain about the shadowed template parameter. 1874 if (!D.isInvalidType()) 1875 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1876 D.setInvalidType(); 1877 1878 // Just pretend that we didn't see the previous declaration. 1879 PrevDecl = 0; 1880 } 1881 1882 // In C++, the previous declaration we find might be a tag type 1883 // (class or enum). In this case, the new declaration will hide the 1884 // tag type. Note that this does does not apply if we're declaring a 1885 // typedef (C++ [dcl.typedef]p4). 1886 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1887 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1888 PrevDecl = 0; 1889 1890 bool Redeclaration = false; 1891 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1892 if (TemplateParamLists.size()) { 1893 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1894 return DeclPtrTy(); 1895 } 1896 1897 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1898 } else if (R->isFunctionType()) { 1899 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1900 move(TemplateParamLists), 1901 IsFunctionDefinition, Redeclaration); 1902 } else { 1903 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1904 move(TemplateParamLists), 1905 Redeclaration); 1906 } 1907 1908 if (New == 0) 1909 return DeclPtrTy(); 1910 1911 // If this has an identifier and is not an invalid redeclaration or 1912 // function template specialization, add it to the scope stack. 1913 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1914 !(isa<FunctionDecl>(New) && 1915 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1916 PushOnScopeChains(New, S); 1917 1918 return DeclPtrTy::make(New); 1919} 1920 1921/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1922/// types into constant array types in certain situations which would otherwise 1923/// be errors (for GCC compatibility). 1924static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1925 ASTContext &Context, 1926 bool &SizeIsNegative) { 1927 // This method tries to turn a variable array into a constant 1928 // array even when the size isn't an ICE. This is necessary 1929 // for compatibility with code that depends on gcc's buggy 1930 // constant expression folding, like struct {char x[(int)(char*)2];} 1931 SizeIsNegative = false; 1932 1933 QualifierCollector Qs; 1934 const Type *Ty = Qs.strip(T); 1935 1936 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1937 QualType Pointee = PTy->getPointeeType(); 1938 QualType FixedType = 1939 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1940 if (FixedType.isNull()) return FixedType; 1941 FixedType = Context.getPointerType(FixedType); 1942 return Qs.apply(FixedType); 1943 } 1944 1945 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1946 if (!VLATy) 1947 return QualType(); 1948 // FIXME: We should probably handle this case 1949 if (VLATy->getElementType()->isVariablyModifiedType()) 1950 return QualType(); 1951 1952 Expr::EvalResult EvalResult; 1953 if (!VLATy->getSizeExpr() || 1954 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1955 !EvalResult.Val.isInt()) 1956 return QualType(); 1957 1958 llvm::APSInt &Res = EvalResult.Val.getInt(); 1959 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1960 // TODO: preserve the size expression in declarator info 1961 return Context.getConstantArrayType(VLATy->getElementType(), 1962 Res, ArrayType::Normal, 0); 1963 } 1964 1965 SizeIsNegative = true; 1966 return QualType(); 1967} 1968 1969/// \brief Register the given locally-scoped external C declaration so 1970/// that it can be found later for redeclarations 1971void 1972Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1973 Scope *S) { 1974 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1975 "Decl is not a locally-scoped decl!"); 1976 // Note that we have a locally-scoped external with this name. 1977 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1978 1979 if (!PrevDecl) 1980 return; 1981 1982 // If there was a previous declaration of this variable, it may be 1983 // in our identifier chain. Update the identifier chain with the new 1984 // declaration. 1985 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1986 // The previous declaration was found on the identifer resolver 1987 // chain, so remove it from its scope. 1988 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1989 S = S->getParent(); 1990 1991 if (S) 1992 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1993 } 1994} 1995 1996/// \brief Diagnose function specifiers on a declaration of an identifier that 1997/// does not identify a function. 1998void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1999 // FIXME: We should probably indicate the identifier in question to avoid 2000 // confusion for constructs like "inline int a(), b;" 2001 if (D.getDeclSpec().isInlineSpecified()) 2002 Diag(D.getDeclSpec().getInlineSpecLoc(), 2003 diag::err_inline_non_function); 2004 2005 if (D.getDeclSpec().isVirtualSpecified()) 2006 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2007 diag::err_virtual_non_function); 2008 2009 if (D.getDeclSpec().isExplicitSpecified()) 2010 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2011 diag::err_explicit_non_function); 2012} 2013 2014NamedDecl* 2015Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2016 QualType R, DeclaratorInfo *DInfo, 2017 NamedDecl* PrevDecl, bool &Redeclaration) { 2018 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2019 if (D.getCXXScopeSpec().isSet()) { 2020 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2021 << D.getCXXScopeSpec().getRange(); 2022 D.setInvalidType(); 2023 // Pretend we didn't see the scope specifier. 2024 DC = 0; 2025 } 2026 2027 if (getLangOptions().CPlusPlus) { 2028 // Check that there are no default arguments (C++ only). 2029 CheckExtraCXXDefaultArguments(D); 2030 } 2031 2032 DiagnoseFunctionSpecifiers(D); 2033 2034 if (D.getDeclSpec().isThreadSpecified()) 2035 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2036 2037 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 2038 if (!NewTD) return 0; 2039 2040 // Handle attributes prior to checking for duplicates in MergeVarDecl 2041 ProcessDeclAttributes(S, NewTD, D); 2042 // Merge the decl with the existing one if appropriate. If the decl is 2043 // in an outer scope, it isn't the same thing. 2044 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2045 Redeclaration = true; 2046 MergeTypeDefDecl(NewTD, PrevDecl); 2047 } 2048 2049 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2050 // then it shall have block scope. 2051 QualType T = NewTD->getUnderlyingType(); 2052 if (T->isVariablyModifiedType()) { 2053 CurFunctionNeedsScopeChecking = true; 2054 2055 if (S->getFnParent() == 0) { 2056 bool SizeIsNegative; 2057 QualType FixedTy = 2058 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2059 if (!FixedTy.isNull()) { 2060 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2061 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2062 } else { 2063 if (SizeIsNegative) 2064 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2065 else if (T->isVariableArrayType()) 2066 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2067 else 2068 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2069 NewTD->setInvalidDecl(); 2070 } 2071 } 2072 } 2073 2074 // If this is the C FILE type, notify the AST context. 2075 if (IdentifierInfo *II = NewTD->getIdentifier()) 2076 if (!NewTD->isInvalidDecl() && 2077 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2078 if (II->isStr("FILE")) 2079 Context.setFILEDecl(NewTD); 2080 else if (II->isStr("jmp_buf")) 2081 Context.setjmp_bufDecl(NewTD); 2082 else if (II->isStr("sigjmp_buf")) 2083 Context.setsigjmp_bufDecl(NewTD); 2084 } 2085 2086 return NewTD; 2087} 2088 2089/// \brief Determines whether the given declaration is an out-of-scope 2090/// previous declaration. 2091/// 2092/// This routine should be invoked when name lookup has found a 2093/// previous declaration (PrevDecl) that is not in the scope where a 2094/// new declaration by the same name is being introduced. If the new 2095/// declaration occurs in a local scope, previous declarations with 2096/// linkage may still be considered previous declarations (C99 2097/// 6.2.2p4-5, C++ [basic.link]p6). 2098/// 2099/// \param PrevDecl the previous declaration found by name 2100/// lookup 2101/// 2102/// \param DC the context in which the new declaration is being 2103/// declared. 2104/// 2105/// \returns true if PrevDecl is an out-of-scope previous declaration 2106/// for a new delcaration with the same name. 2107static bool 2108isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2109 ASTContext &Context) { 2110 if (!PrevDecl) 2111 return 0; 2112 2113 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2114 // case we need to check each of the overloaded functions. 2115 if (!PrevDecl->hasLinkage()) 2116 return false; 2117 2118 if (Context.getLangOptions().CPlusPlus) { 2119 // C++ [basic.link]p6: 2120 // If there is a visible declaration of an entity with linkage 2121 // having the same name and type, ignoring entities declared 2122 // outside the innermost enclosing namespace scope, the block 2123 // scope declaration declares that same entity and receives the 2124 // linkage of the previous declaration. 2125 DeclContext *OuterContext = DC->getLookupContext(); 2126 if (!OuterContext->isFunctionOrMethod()) 2127 // This rule only applies to block-scope declarations. 2128 return false; 2129 else { 2130 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2131 if (PrevOuterContext->isRecord()) 2132 // We found a member function: ignore it. 2133 return false; 2134 else { 2135 // Find the innermost enclosing namespace for the new and 2136 // previous declarations. 2137 while (!OuterContext->isFileContext()) 2138 OuterContext = OuterContext->getParent(); 2139 while (!PrevOuterContext->isFileContext()) 2140 PrevOuterContext = PrevOuterContext->getParent(); 2141 2142 // The previous declaration is in a different namespace, so it 2143 // isn't the same function. 2144 if (OuterContext->getPrimaryContext() != 2145 PrevOuterContext->getPrimaryContext()) 2146 return false; 2147 } 2148 } 2149 } 2150 2151 return true; 2152} 2153 2154NamedDecl* 2155Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2156 QualType R, DeclaratorInfo *DInfo, 2157 NamedDecl* PrevDecl, 2158 MultiTemplateParamsArg TemplateParamLists, 2159 bool &Redeclaration) { 2160 DeclarationName Name = GetNameForDeclarator(D); 2161 2162 // Check that there are no default arguments (C++ only). 2163 if (getLangOptions().CPlusPlus) 2164 CheckExtraCXXDefaultArguments(D); 2165 2166 VarDecl *NewVD; 2167 VarDecl::StorageClass SC; 2168 switch (D.getDeclSpec().getStorageClassSpec()) { 2169 default: assert(0 && "Unknown storage class!"); 2170 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2171 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2172 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2173 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2174 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2175 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2176 case DeclSpec::SCS_mutable: 2177 // mutable can only appear on non-static class members, so it's always 2178 // an error here 2179 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2180 D.setInvalidType(); 2181 SC = VarDecl::None; 2182 break; 2183 } 2184 2185 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2186 if (!II) { 2187 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2188 << Name.getAsString(); 2189 return 0; 2190 } 2191 2192 DiagnoseFunctionSpecifiers(D); 2193 2194 if (!DC->isRecord() && S->getFnParent() == 0) { 2195 // C99 6.9p2: The storage-class specifiers auto and register shall not 2196 // appear in the declaration specifiers in an external declaration. 2197 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2198 2199 // If this is a register variable with an asm label specified, then this 2200 // is a GNU extension. 2201 if (SC == VarDecl::Register && D.getAsmLabel()) 2202 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2203 else 2204 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2205 D.setInvalidType(); 2206 } 2207 } 2208 if (DC->isRecord() && !CurContext->isRecord()) { 2209 // This is an out-of-line definition of a static data member. 2210 if (SC == VarDecl::Static) { 2211 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2212 diag::err_static_out_of_line) 2213 << CodeModificationHint::CreateRemoval( 2214 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2215 } else if (SC == VarDecl::None) 2216 SC = VarDecl::Static; 2217 } 2218 if (SC == VarDecl::Static) { 2219 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2220 if (RD->isLocalClass()) 2221 Diag(D.getIdentifierLoc(), 2222 diag::err_static_data_member_not_allowed_in_local_class) 2223 << Name << RD->getDeclName(); 2224 } 2225 } 2226 2227 // Match up the template parameter lists with the scope specifier, then 2228 // determine whether we have a template or a template specialization. 2229 bool isExplicitSpecialization = false; 2230 if (TemplateParameterList *TemplateParams 2231 = MatchTemplateParametersToScopeSpecifier( 2232 D.getDeclSpec().getSourceRange().getBegin(), 2233 D.getCXXScopeSpec(), 2234 (TemplateParameterList**)TemplateParamLists.get(), 2235 TemplateParamLists.size(), 2236 isExplicitSpecialization)) { 2237 if (TemplateParams->size() > 0) { 2238 // There is no such thing as a variable template. 2239 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2240 << II 2241 << SourceRange(TemplateParams->getTemplateLoc(), 2242 TemplateParams->getRAngleLoc()); 2243 return 0; 2244 } else { 2245 // There is an extraneous 'template<>' for this variable. Complain 2246 // about it, but allow the declaration of the variable. 2247 Diag(TemplateParams->getTemplateLoc(), 2248 diag::err_template_variable_noparams) 2249 << II 2250 << SourceRange(TemplateParams->getTemplateLoc(), 2251 TemplateParams->getRAngleLoc()); 2252 2253 isExplicitSpecialization = true; 2254 } 2255 } 2256 2257 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2258 II, R, DInfo, SC); 2259 2260 if (D.isInvalidType()) 2261 NewVD->setInvalidDecl(); 2262 2263 if (D.getDeclSpec().isThreadSpecified()) { 2264 if (NewVD->hasLocalStorage()) 2265 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2266 else if (!Context.Target.isTLSSupported()) 2267 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2268 else 2269 NewVD->setThreadSpecified(true); 2270 } 2271 2272 // Set the lexical context. If the declarator has a C++ scope specifier, the 2273 // lexical context will be different from the semantic context. 2274 NewVD->setLexicalDeclContext(CurContext); 2275 2276 // Handle attributes prior to checking for duplicates in MergeVarDecl 2277 ProcessDeclAttributes(S, NewVD, D); 2278 2279 // Handle GNU asm-label extension (encoded as an attribute). 2280 if (Expr *E = (Expr*) D.getAsmLabel()) { 2281 // The parser guarantees this is a string. 2282 StringLiteral *SE = cast<StringLiteral>(E); 2283 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2284 SE->getByteLength()))); 2285 } 2286 2287 // If name lookup finds a previous declaration that is not in the 2288 // same scope as the new declaration, this may still be an 2289 // acceptable redeclaration. 2290 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2291 !(NewVD->hasLinkage() && 2292 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2293 PrevDecl = 0; 2294 2295 // Merge the decl with the existing one if appropriate. 2296 if (PrevDecl) { 2297 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2298 // The user tried to define a non-static data member 2299 // out-of-line (C++ [dcl.meaning]p1). 2300 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2301 << D.getCXXScopeSpec().getRange(); 2302 PrevDecl = 0; 2303 NewVD->setInvalidDecl(); 2304 } 2305 } else if (D.getCXXScopeSpec().isSet()) { 2306 // No previous declaration in the qualifying scope. 2307 Diag(D.getIdentifierLoc(), diag::err_no_member) 2308 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2309 << D.getCXXScopeSpec().getRange(); 2310 NewVD->setInvalidDecl(); 2311 } 2312 2313 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2314 2315 // This is an explicit specialization of a static data member. Check it. 2316 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2317 CheckMemberSpecialization(NewVD, PrevDecl)) 2318 NewVD->setInvalidDecl(); 2319 2320 // attributes declared post-definition are currently ignored 2321 if (PrevDecl) { 2322 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2323 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2324 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2325 Diag(Def->getLocation(), diag::note_previous_definition); 2326 } 2327 } 2328 2329 // If this is a locally-scoped extern C variable, update the map of 2330 // such variables. 2331 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2332 !NewVD->isInvalidDecl()) 2333 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2334 2335 return NewVD; 2336} 2337 2338/// \brief Perform semantic checking on a newly-created variable 2339/// declaration. 2340/// 2341/// This routine performs all of the type-checking required for a 2342/// variable declaration once it has been built. It is used both to 2343/// check variables after they have been parsed and their declarators 2344/// have been translated into a declaration, and to check variables 2345/// that have been instantiated from a template. 2346/// 2347/// Sets NewVD->isInvalidDecl() if an error was encountered. 2348void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2349 bool &Redeclaration) { 2350 // If the decl is already known invalid, don't check it. 2351 if (NewVD->isInvalidDecl()) 2352 return; 2353 2354 QualType T = NewVD->getType(); 2355 2356 if (T->isObjCInterfaceType()) { 2357 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2358 return NewVD->setInvalidDecl(); 2359 } 2360 2361 // The variable can not have an abstract class type. 2362 if (RequireNonAbstractType(NewVD->getLocation(), T, 2363 diag::err_abstract_type_in_decl, 2364 AbstractVariableType)) 2365 return NewVD->setInvalidDecl(); 2366 2367 // Emit an error if an address space was applied to decl with local storage. 2368 // This includes arrays of objects with address space qualifiers, but not 2369 // automatic variables that point to other address spaces. 2370 // ISO/IEC TR 18037 S5.1.2 2371 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2372 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2373 return NewVD->setInvalidDecl(); 2374 } 2375 2376 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2377 && !NewVD->hasAttr<BlocksAttr>()) 2378 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2379 2380 bool isVM = T->isVariablyModifiedType(); 2381 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2382 NewVD->hasAttr<BlocksAttr>()) 2383 CurFunctionNeedsScopeChecking = true; 2384 2385 if ((isVM && NewVD->hasLinkage()) || 2386 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2387 bool SizeIsNegative; 2388 QualType FixedTy = 2389 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2390 2391 if (FixedTy.isNull() && T->isVariableArrayType()) { 2392 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2393 // FIXME: This won't give the correct result for 2394 // int a[10][n]; 2395 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2396 2397 if (NewVD->isFileVarDecl()) 2398 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2399 << SizeRange; 2400 else if (NewVD->getStorageClass() == VarDecl::Static) 2401 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2402 << SizeRange; 2403 else 2404 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2405 << SizeRange; 2406 return NewVD->setInvalidDecl(); 2407 } 2408 2409 if (FixedTy.isNull()) { 2410 if (NewVD->isFileVarDecl()) 2411 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2412 else 2413 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2414 return NewVD->setInvalidDecl(); 2415 } 2416 2417 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2418 NewVD->setType(FixedTy); 2419 } 2420 2421 if (!PrevDecl && NewVD->isExternC()) { 2422 // Since we did not find anything by this name and we're declaring 2423 // an extern "C" variable, look for a non-visible extern "C" 2424 // declaration with the same name. 2425 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2426 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2427 if (Pos != LocallyScopedExternalDecls.end()) 2428 PrevDecl = Pos->second; 2429 } 2430 2431 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2432 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2433 << T; 2434 return NewVD->setInvalidDecl(); 2435 } 2436 2437 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2438 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2439 return NewVD->setInvalidDecl(); 2440 } 2441 2442 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2443 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2444 return NewVD->setInvalidDecl(); 2445 } 2446 2447 if (PrevDecl) { 2448 Redeclaration = true; 2449 MergeVarDecl(NewVD, PrevDecl); 2450 } 2451} 2452 2453static bool isUsingDecl(Decl *D) { 2454 return isa<UsingDecl>(D) || 2455 isa<UnresolvedUsingTypenameDecl>(D) || 2456 isa<UnresolvedUsingValueDecl>(D); 2457} 2458 2459/// \brief Data used with FindOverriddenMethod 2460struct FindOverriddenMethodData { 2461 Sema *S; 2462 CXXMethodDecl *Method; 2463}; 2464 2465/// \brief Member lookup function that determines whether a given C++ 2466/// method overrides a method in a base class, to be used with 2467/// CXXRecordDecl::lookupInBases(). 2468static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2469 CXXBasePath &Path, 2470 void *UserData) { 2471 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2472 2473 FindOverriddenMethodData *Data 2474 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2475 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2476 Path.Decls.first != Path.Decls.second; 2477 ++Path.Decls.first) { 2478 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2479 OverloadedFunctionDecl::function_iterator MatchedDecl; 2480 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2481 return true; 2482 } 2483 } 2484 2485 return false; 2486} 2487 2488NamedDecl* 2489Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2490 QualType R, DeclaratorInfo *DInfo, 2491 NamedDecl* PrevDecl, 2492 MultiTemplateParamsArg TemplateParamLists, 2493 bool IsFunctionDefinition, bool &Redeclaration) { 2494 assert(R.getTypePtr()->isFunctionType()); 2495 2496 DeclarationName Name = GetNameForDeclarator(D); 2497 FunctionDecl::StorageClass SC = FunctionDecl::None; 2498 switch (D.getDeclSpec().getStorageClassSpec()) { 2499 default: assert(0 && "Unknown storage class!"); 2500 case DeclSpec::SCS_auto: 2501 case DeclSpec::SCS_register: 2502 case DeclSpec::SCS_mutable: 2503 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2504 diag::err_typecheck_sclass_func); 2505 D.setInvalidType(); 2506 break; 2507 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2508 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2509 case DeclSpec::SCS_static: { 2510 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2511 // C99 6.7.1p5: 2512 // The declaration of an identifier for a function that has 2513 // block scope shall have no explicit storage-class specifier 2514 // other than extern 2515 // See also (C++ [dcl.stc]p4). 2516 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2517 diag::err_static_block_func); 2518 SC = FunctionDecl::None; 2519 } else 2520 SC = FunctionDecl::Static; 2521 break; 2522 } 2523 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2524 } 2525 2526 if (D.getDeclSpec().isThreadSpecified()) 2527 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2528 2529 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2530 bool isInline = D.getDeclSpec().isInlineSpecified(); 2531 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2532 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2533 2534 // Check that the return type is not an abstract class type. 2535 // For record types, this is done by the AbstractClassUsageDiagnoser once 2536 // the class has been completely parsed. 2537 if (!DC->isRecord() && 2538 RequireNonAbstractType(D.getIdentifierLoc(), 2539 R->getAs<FunctionType>()->getResultType(), 2540 diag::err_abstract_type_in_decl, 2541 AbstractReturnType)) 2542 D.setInvalidType(); 2543 2544 // Do not allow returning a objc interface by-value. 2545 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2546 Diag(D.getIdentifierLoc(), 2547 diag::err_object_cannot_be_passed_returned_by_value) << 0 2548 << R->getAs<FunctionType>()->getResultType(); 2549 D.setInvalidType(); 2550 } 2551 2552 bool isVirtualOkay = false; 2553 FunctionDecl *NewFD; 2554 2555 if (isFriend) { 2556 // DC is the namespace in which the function is being declared. 2557 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2558 "friend function being created in a non-namespace context"); 2559 2560 // C++ [class.friend]p5 2561 // A function can be defined in a friend declaration of a 2562 // class . . . . Such a function is implicitly inline. 2563 isInline |= IsFunctionDefinition; 2564 } 2565 2566 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2567 // This is a C++ constructor declaration. 2568 assert(DC->isRecord() && 2569 "Constructors can only be declared in a member context"); 2570 2571 R = CheckConstructorDeclarator(D, R, SC); 2572 2573 // Create the new declaration 2574 NewFD = CXXConstructorDecl::Create(Context, 2575 cast<CXXRecordDecl>(DC), 2576 D.getIdentifierLoc(), Name, R, DInfo, 2577 isExplicit, isInline, 2578 /*isImplicitlyDeclared=*/false); 2579 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2580 // This is a C++ destructor declaration. 2581 if (DC->isRecord()) { 2582 R = CheckDestructorDeclarator(D, SC); 2583 2584 NewFD = CXXDestructorDecl::Create(Context, 2585 cast<CXXRecordDecl>(DC), 2586 D.getIdentifierLoc(), Name, R, 2587 isInline, 2588 /*isImplicitlyDeclared=*/false); 2589 2590 isVirtualOkay = true; 2591 } else { 2592 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2593 2594 // Create a FunctionDecl to satisfy the function definition parsing 2595 // code path. 2596 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2597 Name, R, DInfo, SC, isInline, 2598 /*hasPrototype=*/true); 2599 D.setInvalidType(); 2600 } 2601 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2602 if (!DC->isRecord()) { 2603 Diag(D.getIdentifierLoc(), 2604 diag::err_conv_function_not_member); 2605 return 0; 2606 } 2607 2608 CheckConversionDeclarator(D, R, SC); 2609 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2610 D.getIdentifierLoc(), Name, R, DInfo, 2611 isInline, isExplicit); 2612 2613 isVirtualOkay = true; 2614 } else if (DC->isRecord()) { 2615 // If the of the function is the same as the name of the record, then this 2616 // must be an invalid constructor that has a return type. 2617 // (The parser checks for a return type and makes the declarator a 2618 // constructor if it has no return type). 2619 // must have an invalid constructor that has a return type 2620 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2621 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2622 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2623 << SourceRange(D.getIdentifierLoc()); 2624 return 0; 2625 } 2626 2627 bool isStatic = SC == FunctionDecl::Static; 2628 2629 // [class.free]p1: 2630 // Any allocation function for a class T is a static member 2631 // (even if not explicitly declared static). 2632 if (Name.getCXXOverloadedOperator() == OO_New || 2633 Name.getCXXOverloadedOperator() == OO_Array_New) 2634 isStatic = true; 2635 2636 // [class.free]p6 Any deallocation function for a class X is a static member 2637 // (even if not explicitly declared static). 2638 if (Name.getCXXOverloadedOperator() == OO_Delete || 2639 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2640 isStatic = true; 2641 2642 // This is a C++ method declaration. 2643 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2644 D.getIdentifierLoc(), Name, R, DInfo, 2645 isStatic, isInline); 2646 2647 isVirtualOkay = !isStatic; 2648 } else { 2649 // Determine whether the function was written with a 2650 // prototype. This true when: 2651 // - we're in C++ (where every function has a prototype), 2652 // - there is a prototype in the declarator, or 2653 // - the type R of the function is some kind of typedef or other reference 2654 // to a type name (which eventually refers to a function type). 2655 bool HasPrototype = 2656 getLangOptions().CPlusPlus || 2657 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2658 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2659 2660 NewFD = FunctionDecl::Create(Context, DC, 2661 D.getIdentifierLoc(), 2662 Name, R, DInfo, SC, isInline, HasPrototype); 2663 } 2664 2665 if (D.isInvalidType()) 2666 NewFD->setInvalidDecl(); 2667 2668 // Set the lexical context. If the declarator has a C++ 2669 // scope specifier, or is the object of a friend declaration, the 2670 // lexical context will be different from the semantic context. 2671 NewFD->setLexicalDeclContext(CurContext); 2672 2673 // Match up the template parameter lists with the scope specifier, then 2674 // determine whether we have a template or a template specialization. 2675 FunctionTemplateDecl *FunctionTemplate = 0; 2676 bool isExplicitSpecialization = false; 2677 bool isFunctionTemplateSpecialization = false; 2678 if (TemplateParameterList *TemplateParams 2679 = MatchTemplateParametersToScopeSpecifier( 2680 D.getDeclSpec().getSourceRange().getBegin(), 2681 D.getCXXScopeSpec(), 2682 (TemplateParameterList**)TemplateParamLists.get(), 2683 TemplateParamLists.size(), 2684 isExplicitSpecialization)) { 2685 if (TemplateParams->size() > 0) { 2686 // This is a function template 2687 2688 // Check that we can declare a template here. 2689 if (CheckTemplateDeclScope(S, TemplateParams)) 2690 return 0; 2691 2692 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2693 NewFD->getLocation(), 2694 Name, TemplateParams, 2695 NewFD); 2696 FunctionTemplate->setLexicalDeclContext(CurContext); 2697 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2698 } else { 2699 // This is a function template specialization. 2700 isFunctionTemplateSpecialization = true; 2701 } 2702 2703 // FIXME: Free this memory properly. 2704 TemplateParamLists.release(); 2705 } 2706 2707 // C++ [dcl.fct.spec]p5: 2708 // The virtual specifier shall only be used in declarations of 2709 // nonstatic class member functions that appear within a 2710 // member-specification of a class declaration; see 10.3. 2711 // 2712 if (isVirtual && !NewFD->isInvalidDecl()) { 2713 if (!isVirtualOkay) { 2714 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2715 diag::err_virtual_non_function); 2716 } else if (!CurContext->isRecord()) { 2717 // 'virtual' was specified outside of the class. 2718 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2719 << CodeModificationHint::CreateRemoval( 2720 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2721 } else { 2722 // Okay: Add virtual to the method. 2723 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2724 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2725 CurClass->setAggregate(false); 2726 CurClass->setPOD(false); 2727 CurClass->setEmpty(false); 2728 CurClass->setPolymorphic(true); 2729 CurClass->setHasTrivialConstructor(false); 2730 CurClass->setHasTrivialCopyConstructor(false); 2731 CurClass->setHasTrivialCopyAssignment(false); 2732 } 2733 } 2734 2735 if (isFriend) { 2736 if (FunctionTemplate) { 2737 FunctionTemplate->setObjectOfFriendDecl( 2738 /* PreviouslyDeclared= */ PrevDecl != NULL); 2739 FunctionTemplate->setAccess(AS_public); 2740 } 2741 else 2742 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2743 2744 NewFD->setAccess(AS_public); 2745 } 2746 2747 2748 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2749 // Look for virtual methods in base classes that this method might override. 2750 CXXBasePaths Paths; 2751 FindOverriddenMethodData Data; 2752 Data.Method = NewMD; 2753 Data.S = this; 2754 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2755 Paths)) { 2756 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2757 E = Paths.found_decls_end(); I != E; ++I) { 2758 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2759 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2760 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2761 NewMD->addOverriddenMethod(OldMD); 2762 } 2763 } 2764 } 2765 } 2766 2767 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2768 !CurContext->isRecord()) { 2769 // C++ [class.static]p1: 2770 // A data or function member of a class may be declared static 2771 // in a class definition, in which case it is a static member of 2772 // the class. 2773 2774 // Complain about the 'static' specifier if it's on an out-of-line 2775 // member function definition. 2776 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2777 diag::err_static_out_of_line) 2778 << CodeModificationHint::CreateRemoval( 2779 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2780 } 2781 2782 // Handle GNU asm-label extension (encoded as an attribute). 2783 if (Expr *E = (Expr*) D.getAsmLabel()) { 2784 // The parser guarantees this is a string. 2785 StringLiteral *SE = cast<StringLiteral>(E); 2786 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2787 SE->getByteLength()))); 2788 } 2789 2790 // Copy the parameter declarations from the declarator D to the function 2791 // declaration NewFD, if they are available. First scavenge them into Params. 2792 llvm::SmallVector<ParmVarDecl*, 16> Params; 2793 if (D.getNumTypeObjects() > 0) { 2794 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2795 2796 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2797 // function that takes no arguments, not a function that takes a 2798 // single void argument. 2799 // We let through "const void" here because Sema::GetTypeForDeclarator 2800 // already checks for that case. 2801 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2802 FTI.ArgInfo[0].Param && 2803 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2804 // Empty arg list, don't push any params. 2805 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2806 2807 // In C++, the empty parameter-type-list must be spelled "void"; a 2808 // typedef of void is not permitted. 2809 if (getLangOptions().CPlusPlus && 2810 Param->getType().getUnqualifiedType() != Context.VoidTy) 2811 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2812 // FIXME: Leaks decl? 2813 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2814 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2815 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2816 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2817 Param->setDeclContext(NewFD); 2818 Params.push_back(Param); 2819 } 2820 } 2821 2822 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2823 // When we're declaring a function with a typedef, typeof, etc as in the 2824 // following example, we'll need to synthesize (unnamed) 2825 // parameters for use in the declaration. 2826 // 2827 // @code 2828 // typedef void fn(int); 2829 // fn f; 2830 // @endcode 2831 2832 // Synthesize a parameter for each argument type. 2833 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2834 AE = FT->arg_type_end(); AI != AE; ++AI) { 2835 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2836 SourceLocation(), 0, 2837 *AI, /*DInfo=*/0, 2838 VarDecl::None, 0); 2839 Param->setImplicit(); 2840 Params.push_back(Param); 2841 } 2842 } else { 2843 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2844 "Should not need args for typedef of non-prototype fn"); 2845 } 2846 // Finally, we know we have the right number of parameters, install them. 2847 NewFD->setParams(Context, Params.data(), Params.size()); 2848 2849 // If name lookup finds a previous declaration that is not in the 2850 // same scope as the new declaration, this may still be an 2851 // acceptable redeclaration. 2852 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2853 !(NewFD->hasLinkage() && 2854 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2855 PrevDecl = 0; 2856 2857 // If the declarator is a template-id, translate the parser's template 2858 // argument list into our AST format. 2859 bool HasExplicitTemplateArgs = false; 2860 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 2861 SourceLocation LAngleLoc, RAngleLoc; 2862 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2863 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2864 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2865 TemplateId->getTemplateArgs(), 2866 TemplateId->NumArgs); 2867 translateTemplateArguments(TemplateArgsPtr, 2868 TemplateArgs); 2869 TemplateArgsPtr.release(); 2870 2871 HasExplicitTemplateArgs = true; 2872 LAngleLoc = TemplateId->LAngleLoc; 2873 RAngleLoc = TemplateId->RAngleLoc; 2874 2875 if (FunctionTemplate) { 2876 // FIXME: Diagnose function template with explicit template 2877 // arguments. 2878 HasExplicitTemplateArgs = false; 2879 } else if (!isFunctionTemplateSpecialization && 2880 !D.getDeclSpec().isFriendSpecified()) { 2881 // We have encountered something that the user meant to be a 2882 // specialization (because it has explicitly-specified template 2883 // arguments) but that was not introduced with a "template<>" (or had 2884 // too few of them). 2885 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2886 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2887 << CodeModificationHint::CreateInsertion( 2888 D.getDeclSpec().getSourceRange().getBegin(), 2889 "template<> "); 2890 isFunctionTemplateSpecialization = true; 2891 } 2892 } 2893 2894 if (isFunctionTemplateSpecialization) { 2895 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2896 LAngleLoc, TemplateArgs.data(), 2897 TemplateArgs.size(), RAngleLoc, 2898 PrevDecl)) 2899 NewFD->setInvalidDecl(); 2900 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2901 CheckMemberSpecialization(NewFD, PrevDecl)) 2902 NewFD->setInvalidDecl(); 2903 2904 // Perform semantic checking on the function declaration. 2905 bool OverloadableAttrRequired = false; // FIXME: HACK! 2906 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2907 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2908 2909 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2910 // An out-of-line member function declaration must also be a 2911 // definition (C++ [dcl.meaning]p1). 2912 // Note that this is not the case for explicit specializations of 2913 // function templates or member functions of class templates, per 2914 // C++ [temp.expl.spec]p2. 2915 if (!IsFunctionDefinition && !isFriend && 2916 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2917 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2918 << D.getCXXScopeSpec().getRange(); 2919 NewFD->setInvalidDecl(); 2920 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2921 // The user tried to provide an out-of-line definition for a 2922 // function that is a member of a class or namespace, but there 2923 // was no such member function declared (C++ [class.mfct]p2, 2924 // C++ [namespace.memdef]p2). For example: 2925 // 2926 // class X { 2927 // void f() const; 2928 // }; 2929 // 2930 // void X::f() { } // ill-formed 2931 // 2932 // Complain about this problem, and attempt to suggest close 2933 // matches (e.g., those that differ only in cv-qualifiers and 2934 // whether the parameter types are references). 2935 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2936 << Name << DC << D.getCXXScopeSpec().getRange(); 2937 NewFD->setInvalidDecl(); 2938 2939 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2940 LookupResult::ForRedeclaration); 2941 LookupQualifiedName(Prev, DC); 2942 assert(!Prev.isAmbiguous() && 2943 "Cannot have an ambiguity in previous-declaration lookup"); 2944 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2945 Func != FuncEnd; ++Func) { 2946 if (isa<FunctionDecl>(*Func) && 2947 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2948 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2949 } 2950 2951 PrevDecl = 0; 2952 } 2953 } 2954 2955 // Handle attributes. We need to have merged decls when handling attributes 2956 // (for example to check for conflicts, etc). 2957 // FIXME: This needs to happen before we merge declarations. Then, 2958 // let attribute merging cope with attribute conflicts. 2959 ProcessDeclAttributes(S, NewFD, D); 2960 2961 // attributes declared post-definition are currently ignored 2962 if (Redeclaration && PrevDecl) { 2963 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2964 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2965 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2966 Diag(Def->getLocation(), diag::note_previous_definition); 2967 } 2968 } 2969 2970 AddKnownFunctionAttributes(NewFD); 2971 2972 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2973 // If a function name is overloadable in C, then every function 2974 // with that name must be marked "overloadable". 2975 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2976 << Redeclaration << NewFD; 2977 if (PrevDecl) 2978 Diag(PrevDecl->getLocation(), 2979 diag::note_attribute_overloadable_prev_overload); 2980 NewFD->addAttr(::new (Context) OverloadableAttr()); 2981 } 2982 2983 // If this is a locally-scoped extern C function, update the 2984 // map of such names. 2985 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2986 && !NewFD->isInvalidDecl()) 2987 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2988 2989 // Set this FunctionDecl's range up to the right paren. 2990 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2991 2992 if (FunctionTemplate && NewFD->isInvalidDecl()) 2993 FunctionTemplate->setInvalidDecl(); 2994 2995 if (FunctionTemplate) 2996 return FunctionTemplate; 2997 2998 return NewFD; 2999} 3000 3001/// \brief Perform semantic checking of a new function declaration. 3002/// 3003/// Performs semantic analysis of the new function declaration 3004/// NewFD. This routine performs all semantic checking that does not 3005/// require the actual declarator involved in the declaration, and is 3006/// used both for the declaration of functions as they are parsed 3007/// (called via ActOnDeclarator) and for the declaration of functions 3008/// that have been instantiated via C++ template instantiation (called 3009/// via InstantiateDecl). 3010/// 3011/// \param IsExplicitSpecialiation whether this new function declaration is 3012/// an explicit specialization of the previous declaration. 3013/// 3014/// This sets NewFD->isInvalidDecl() to true if there was an error. 3015void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 3016 bool IsExplicitSpecialization, 3017 bool &Redeclaration, 3018 bool &OverloadableAttrRequired) { 3019 // If NewFD is already known erroneous, don't do any of this checking. 3020 if (NewFD->isInvalidDecl()) 3021 return; 3022 3023 if (NewFD->getResultType()->isVariablyModifiedType()) { 3024 // Functions returning a variably modified type violate C99 6.7.5.2p2 3025 // because all functions have linkage. 3026 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3027 return NewFD->setInvalidDecl(); 3028 } 3029 3030 if (NewFD->isMain()) 3031 CheckMain(NewFD); 3032 3033 // Check for a previous declaration of this name. 3034 if (!PrevDecl && NewFD->isExternC()) { 3035 // Since we did not find anything by this name and we're declaring 3036 // an extern "C" function, look for a non-visible extern "C" 3037 // declaration with the same name. 3038 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3039 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3040 if (Pos != LocallyScopedExternalDecls.end()) 3041 PrevDecl = Pos->second; 3042 } 3043 3044 // Merge or overload the declaration with an existing declaration of 3045 // the same name, if appropriate. 3046 if (PrevDecl) { 3047 // Determine whether NewFD is an overload of PrevDecl or 3048 // a declaration that requires merging. If it's an overload, 3049 // there's no more work to do here; we'll just add the new 3050 // function to the scope. 3051 OverloadedFunctionDecl::function_iterator MatchedDecl; 3052 3053 if (!getLangOptions().CPlusPlus && 3054 AllowOverloadingOfFunction(PrevDecl, Context)) { 3055 OverloadableAttrRequired = true; 3056 3057 // Functions marked "overloadable" must have a prototype (that 3058 // we can't get through declaration merging). 3059 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3060 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3061 << NewFD; 3062 Redeclaration = true; 3063 3064 // Turn this into a variadic function with no parameters. 3065 QualType R = Context.getFunctionType( 3066 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3067 0, 0, true, 0); 3068 NewFD->setType(R); 3069 return NewFD->setInvalidDecl(); 3070 } 3071 } 3072 3073 if (PrevDecl && 3074 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3075 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3076 Redeclaration = true; 3077 Decl *OldDecl = PrevDecl; 3078 3079 // If PrevDecl was an overloaded function, extract the 3080 // FunctionDecl that matched. 3081 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3082 OldDecl = *MatchedDecl; 3083 3084 // NewFD and OldDecl represent declarations that need to be 3085 // merged. 3086 if (MergeFunctionDecl(NewFD, OldDecl)) 3087 return NewFD->setInvalidDecl(); 3088 3089 if (FunctionTemplateDecl *OldTemplateDecl 3090 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3091 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3092 FunctionTemplateDecl *NewTemplateDecl 3093 = NewFD->getDescribedFunctionTemplate(); 3094 assert(NewTemplateDecl && "Template/non-template mismatch"); 3095 if (CXXMethodDecl *Method 3096 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3097 Method->setAccess(OldTemplateDecl->getAccess()); 3098 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3099 } 3100 3101 // If this is an explicit specialization of a member that is a function 3102 // template, mark it as a member specialization. 3103 if (IsExplicitSpecialization && 3104 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3105 NewTemplateDecl->setMemberSpecialization(); 3106 assert(OldTemplateDecl->isMemberSpecialization()); 3107 } 3108 } else { 3109 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3110 NewFD->setAccess(OldDecl->getAccess()); 3111 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3112 } 3113 } 3114 } 3115 3116 // Semantic checking for this function declaration (in isolation). 3117 if (getLangOptions().CPlusPlus) { 3118 // C++-specific checks. 3119 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3120 CheckConstructor(Constructor); 3121 } else if (CXXDestructorDecl *Destructor = 3122 dyn_cast<CXXDestructorDecl>(NewFD)) { 3123 CXXRecordDecl *Record = Destructor->getParent(); 3124 QualType ClassType = Context.getTypeDeclType(Record); 3125 3126 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3127 // type is dependent? Both gcc and edg can handle that. 3128 if (!ClassType->isDependentType()) { 3129 DeclarationName Name 3130 = Context.DeclarationNames.getCXXDestructorName( 3131 Context.getCanonicalType(ClassType)); 3132 if (NewFD->getDeclName() != Name) { 3133 Diag(NewFD->getLocation(), diag::err_destructor_name); 3134 return NewFD->setInvalidDecl(); 3135 } 3136 3137 CheckDestructor(Destructor); 3138 } 3139 3140 Record->setUserDeclaredDestructor(true); 3141 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3142 // user-defined destructor. 3143 Record->setPOD(false); 3144 3145 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3146 // declared destructor. 3147 // FIXME: C++0x: don't do this for "= default" destructors 3148 Record->setHasTrivialDestructor(false); 3149 } else if (CXXConversionDecl *Conversion 3150 = dyn_cast<CXXConversionDecl>(NewFD)) 3151 ActOnConversionDeclarator(Conversion); 3152 3153 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3154 if (NewFD->isOverloadedOperator() && 3155 CheckOverloadedOperatorDeclaration(NewFD)) 3156 return NewFD->setInvalidDecl(); 3157 3158 // In C++, check default arguments now that we have merged decls. Unless 3159 // the lexical context is the class, because in this case this is done 3160 // during delayed parsing anyway. 3161 if (!CurContext->isRecord()) 3162 CheckCXXDefaultArguments(NewFD); 3163 } 3164} 3165 3166void Sema::CheckMain(FunctionDecl* FD) { 3167 // C++ [basic.start.main]p3: A program that declares main to be inline 3168 // or static is ill-formed. 3169 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3170 // shall not appear in a declaration of main. 3171 // static main is not an error under C99, but we should warn about it. 3172 bool isInline = FD->isInlineSpecified(); 3173 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3174 if (isInline || isStatic) { 3175 unsigned diagID = diag::warn_unusual_main_decl; 3176 if (isInline || getLangOptions().CPlusPlus) 3177 diagID = diag::err_unusual_main_decl; 3178 3179 int which = isStatic + (isInline << 1) - 1; 3180 Diag(FD->getLocation(), diagID) << which; 3181 } 3182 3183 QualType T = FD->getType(); 3184 assert(T->isFunctionType() && "function decl is not of function type"); 3185 const FunctionType* FT = T->getAs<FunctionType>(); 3186 3187 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3188 // TODO: add a replacement fixit to turn the return type into 'int'. 3189 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3190 FD->setInvalidDecl(true); 3191 } 3192 3193 // Treat protoless main() as nullary. 3194 if (isa<FunctionNoProtoType>(FT)) return; 3195 3196 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3197 unsigned nparams = FTP->getNumArgs(); 3198 assert(FD->getNumParams() == nparams); 3199 3200 if (nparams > 3) { 3201 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3202 FD->setInvalidDecl(true); 3203 nparams = 3; 3204 } 3205 3206 // FIXME: a lot of the following diagnostics would be improved 3207 // if we had some location information about types. 3208 3209 QualType CharPP = 3210 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3211 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3212 3213 for (unsigned i = 0; i < nparams; ++i) { 3214 QualType AT = FTP->getArgType(i); 3215 3216 bool mismatch = true; 3217 3218 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3219 mismatch = false; 3220 else if (Expected[i] == CharPP) { 3221 // As an extension, the following forms are okay: 3222 // char const ** 3223 // char const * const * 3224 // char * const * 3225 3226 QualifierCollector qs; 3227 const PointerType* PT; 3228 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3229 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3230 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3231 qs.removeConst(); 3232 mismatch = !qs.empty(); 3233 } 3234 } 3235 3236 if (mismatch) { 3237 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3238 // TODO: suggest replacing given type with expected type 3239 FD->setInvalidDecl(true); 3240 } 3241 } 3242 3243 if (nparams == 1 && !FD->isInvalidDecl()) { 3244 Diag(FD->getLocation(), diag::warn_main_one_arg); 3245 } 3246} 3247 3248bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3249 // FIXME: Need strict checking. In C89, we need to check for 3250 // any assignment, increment, decrement, function-calls, or 3251 // commas outside of a sizeof. In C99, it's the same list, 3252 // except that the aforementioned are allowed in unevaluated 3253 // expressions. Everything else falls under the 3254 // "may accept other forms of constant expressions" exception. 3255 // (We never end up here for C++, so the constant expression 3256 // rules there don't matter.) 3257 if (Init->isConstantInitializer(Context)) 3258 return false; 3259 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3260 << Init->getSourceRange(); 3261 return true; 3262} 3263 3264void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3265 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3266} 3267 3268/// AddInitializerToDecl - Adds the initializer Init to the 3269/// declaration dcl. If DirectInit is true, this is C++ direct 3270/// initialization rather than copy initialization. 3271void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3272 Decl *RealDecl = dcl.getAs<Decl>(); 3273 // If there is no declaration, there was an error parsing it. Just ignore 3274 // the initializer. 3275 if (RealDecl == 0) 3276 return; 3277 3278 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3279 // With declarators parsed the way they are, the parser cannot 3280 // distinguish between a normal initializer and a pure-specifier. 3281 // Thus this grotesque test. 3282 IntegerLiteral *IL; 3283 Expr *Init = static_cast<Expr *>(init.get()); 3284 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3285 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3286 if (Method->isVirtualAsWritten()) { 3287 Method->setPure(); 3288 3289 // A class is abstract if at least one function is pure virtual. 3290 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3291 } else if (!Method->isInvalidDecl()) { 3292 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3293 << Method->getDeclName() << Init->getSourceRange(); 3294 Method->setInvalidDecl(); 3295 } 3296 } else { 3297 Diag(Method->getLocation(), diag::err_member_function_initialization) 3298 << Method->getDeclName() << Init->getSourceRange(); 3299 Method->setInvalidDecl(); 3300 } 3301 return; 3302 } 3303 3304 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3305 if (!VDecl) { 3306 if (getLangOptions().CPlusPlus && 3307 RealDecl->getLexicalDeclContext()->isRecord() && 3308 isa<NamedDecl>(RealDecl)) 3309 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3310 << cast<NamedDecl>(RealDecl)->getDeclName(); 3311 else 3312 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3313 RealDecl->setInvalidDecl(); 3314 return; 3315 } 3316 3317 // A definition must end up with a complete type, which means it must be 3318 // complete with the restriction that an array type might be completed by the 3319 // initializer; note that later code assumes this restriction. 3320 QualType BaseDeclType = VDecl->getType(); 3321 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3322 BaseDeclType = Array->getElementType(); 3323 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3324 diag::err_typecheck_decl_incomplete_type)) { 3325 RealDecl->setInvalidDecl(); 3326 return; 3327 } 3328 3329 const VarDecl *Def = 0; 3330 if (VDecl->getDefinition(Def)) { 3331 Diag(VDecl->getLocation(), diag::err_redefinition) 3332 << VDecl->getDeclName(); 3333 Diag(Def->getLocation(), diag::note_previous_definition); 3334 VDecl->setInvalidDecl(); 3335 return; 3336 } 3337 3338 // Take ownership of the expression, now that we're sure we have somewhere 3339 // to put it. 3340 Expr *Init = init.takeAs<Expr>(); 3341 assert(Init && "missing initializer"); 3342 3343 // Get the decls type and save a reference for later, since 3344 // CheckInitializerTypes may change it. 3345 QualType DclT = VDecl->getType(), SavT = DclT; 3346 if (VDecl->isBlockVarDecl()) { 3347 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3348 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3349 VDecl->setInvalidDecl(); 3350 } else 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 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3359 CheckForConstantInitializer(Init, DclT); 3360 } 3361 } 3362 } else if (VDecl->isStaticDataMember() && 3363 VDecl->getLexicalDeclContext()->isRecord()) { 3364 // This is an in-class initialization for a static data member, e.g., 3365 // 3366 // struct S { 3367 // static const int value = 17; 3368 // }; 3369 3370 // Attach the initializer 3371 VDecl->setInit(Context, Init); 3372 3373 // C++ [class.mem]p4: 3374 // A member-declarator can contain a constant-initializer only 3375 // if it declares a static member (9.4) of const integral or 3376 // const enumeration type, see 9.4.2. 3377 QualType T = VDecl->getType(); 3378 if (!T->isDependentType() && 3379 (!Context.getCanonicalType(T).isConstQualified() || 3380 !T->isIntegralType())) { 3381 Diag(VDecl->getLocation(), diag::err_member_initialization) 3382 << VDecl->getDeclName() << Init->getSourceRange(); 3383 VDecl->setInvalidDecl(); 3384 } else { 3385 // C++ [class.static.data]p4: 3386 // If a static data member is of const integral or const 3387 // enumeration type, its declaration in the class definition 3388 // can specify a constant-initializer which shall be an 3389 // integral constant expression (5.19). 3390 if (!Init->isTypeDependent() && 3391 !Init->getType()->isIntegralType()) { 3392 // We have a non-dependent, non-integral or enumeration type. 3393 Diag(Init->getSourceRange().getBegin(), 3394 diag::err_in_class_initializer_non_integral_type) 3395 << Init->getType() << Init->getSourceRange(); 3396 VDecl->setInvalidDecl(); 3397 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3398 // Check whether the expression is a constant expression. 3399 llvm::APSInt Value; 3400 SourceLocation Loc; 3401 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3402 Diag(Loc, diag::err_in_class_initializer_non_constant) 3403 << Init->getSourceRange(); 3404 VDecl->setInvalidDecl(); 3405 } else if (!VDecl->getType()->isDependentType()) 3406 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3407 } 3408 } 3409 } else if (VDecl->isFileVarDecl()) { 3410 if (VDecl->getStorageClass() == VarDecl::Extern) 3411 Diag(VDecl->getLocation(), diag::warn_extern_init); 3412 if (!VDecl->isInvalidDecl()) 3413 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3414 VDecl->getDeclName(), DirectInit)) 3415 VDecl->setInvalidDecl(); 3416 3417 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3418 // Don't check invalid declarations to avoid emitting useless diagnostics. 3419 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3420 // C99 6.7.8p4. All file scoped initializers need to be constant. 3421 CheckForConstantInitializer(Init, DclT); 3422 } 3423 } 3424 // If the type changed, it means we had an incomplete type that was 3425 // completed by the initializer. For example: 3426 // int ary[] = { 1, 3, 5 }; 3427 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3428 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3429 VDecl->setType(DclT); 3430 Init->setType(DclT); 3431 } 3432 3433 Init = MaybeCreateCXXExprWithTemporaries(Init, 3434 /*ShouldDestroyTemporaries=*/true); 3435 // Attach the initializer to the decl. 3436 VDecl->setInit(Context, Init); 3437 3438 // If the previous declaration of VDecl was a tentative definition, 3439 // remove it from the set of tentative definitions. 3440 if (VDecl->getPreviousDeclaration() && 3441 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3442 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3443 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3444 } 3445 3446 return; 3447} 3448 3449void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3450 bool TypeContainsUndeducedAuto) { 3451 Decl *RealDecl = dcl.getAs<Decl>(); 3452 3453 // If there is no declaration, there was an error parsing it. Just ignore it. 3454 if (RealDecl == 0) 3455 return; 3456 3457 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3458 QualType Type = Var->getType(); 3459 3460 // Record tentative definitions. 3461 if (Var->isTentativeDefinition(Context)) { 3462 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3463 InsertPair = 3464 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3465 3466 // Keep the latest definition in the map. If we see 'int i; int i;' we 3467 // want the second one in the map. 3468 InsertPair.first->second = Var; 3469 3470 // However, for the list, we don't care about the order, just make sure 3471 // that there are no dupes for a given declaration name. 3472 if (InsertPair.second) 3473 TentativeDefinitionList.push_back(Var->getDeclName()); 3474 } 3475 3476 // C++ [dcl.init.ref]p3: 3477 // The initializer can be omitted for a reference only in a 3478 // parameter declaration (8.3.5), in the declaration of a 3479 // function return type, in the declaration of a class member 3480 // within its class declaration (9.2), and where the extern 3481 // specifier is explicitly used. 3482 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3483 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3484 << Var->getDeclName() 3485 << SourceRange(Var->getLocation(), Var->getLocation()); 3486 Var->setInvalidDecl(); 3487 return; 3488 } 3489 3490 // C++0x [dcl.spec.auto]p3 3491 if (TypeContainsUndeducedAuto) { 3492 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3493 << Var->getDeclName() << Type; 3494 Var->setInvalidDecl(); 3495 return; 3496 } 3497 3498 // An array without size is an incomplete type, and there are no special 3499 // rules in C++ to make such a definition acceptable. 3500 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3501 !Var->hasExternalStorage()) { 3502 Diag(Var->getLocation(), 3503 diag::err_typecheck_incomplete_array_needs_initializer); 3504 Var->setInvalidDecl(); 3505 return; 3506 } 3507 3508 // C++ [temp.expl.spec]p15: 3509 // An explicit specialization of a static data member of a template is a 3510 // definition if the declaration includes an initializer; otherwise, it 3511 // is a declaration. 3512 if (Var->isStaticDataMember() && 3513 Var->getInstantiatedFromStaticDataMember() && 3514 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3515 return; 3516 3517 // C++ [dcl.init]p9: 3518 // If no initializer is specified for an object, and the object 3519 // is of (possibly cv-qualified) non-POD class type (or array 3520 // thereof), the object shall be default-initialized; if the 3521 // object is of const-qualified type, the underlying class type 3522 // shall have a user-declared default constructor. 3523 // 3524 // FIXME: Diagnose the "user-declared default constructor" bit. 3525 if (getLangOptions().CPlusPlus) { 3526 QualType InitType = Type; 3527 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3528 InitType = Context.getBaseElementType(Array); 3529 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3530 InitType->isRecordType() && !InitType->isDependentType()) { 3531 if (!RequireCompleteType(Var->getLocation(), InitType, 3532 diag::err_invalid_incomplete_type_use)) { 3533 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3534 3535 CXXConstructorDecl *Constructor 3536 = PerformInitializationByConstructor(InitType, 3537 MultiExprArg(*this, 0, 0), 3538 Var->getLocation(), 3539 SourceRange(Var->getLocation(), 3540 Var->getLocation()), 3541 Var->getDeclName(), 3542 IK_Default, 3543 ConstructorArgs); 3544 3545 // FIXME: Location info for the variable initialization? 3546 if (!Constructor) 3547 Var->setInvalidDecl(); 3548 else { 3549 // FIXME: Cope with initialization of arrays 3550 if (!Constructor->isTrivial() && 3551 InitializeVarWithConstructor(Var, Constructor, 3552 move_arg(ConstructorArgs))) 3553 Var->setInvalidDecl(); 3554 3555 FinalizeVarWithDestructor(Var, InitType); 3556 } 3557 } else { 3558 Var->setInvalidDecl(); 3559 } 3560 } 3561 } 3562 3563#if 0 3564 // FIXME: Temporarily disabled because we are not properly parsing 3565 // linkage specifications on declarations, e.g., 3566 // 3567 // extern "C" const CGPoint CGPointerZero; 3568 // 3569 // C++ [dcl.init]p9: 3570 // 3571 // If no initializer is specified for an object, and the 3572 // object is of (possibly cv-qualified) non-POD class type (or 3573 // array thereof), the object shall be default-initialized; if 3574 // the object is of const-qualified type, the underlying class 3575 // type shall have a user-declared default 3576 // constructor. Otherwise, if no initializer is specified for 3577 // an object, the object and its subobjects, if any, have an 3578 // indeterminate initial value; if the object or any of its 3579 // subobjects are of const-qualified type, the program is 3580 // ill-formed. 3581 // 3582 // This isn't technically an error in C, so we don't diagnose it. 3583 // 3584 // FIXME: Actually perform the POD/user-defined default 3585 // constructor check. 3586 if (getLangOptions().CPlusPlus && 3587 Context.getCanonicalType(Type).isConstQualified() && 3588 !Var->hasExternalStorage()) 3589 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3590 << Var->getName() 3591 << SourceRange(Var->getLocation(), Var->getLocation()); 3592#endif 3593 } 3594} 3595 3596Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3597 DeclPtrTy *Group, 3598 unsigned NumDecls) { 3599 llvm::SmallVector<Decl*, 8> Decls; 3600 3601 if (DS.isTypeSpecOwned()) 3602 Decls.push_back((Decl*)DS.getTypeRep()); 3603 3604 for (unsigned i = 0; i != NumDecls; ++i) 3605 if (Decl *D = Group[i].getAs<Decl>()) 3606 Decls.push_back(D); 3607 3608 // Perform semantic analysis that depends on having fully processed both 3609 // the declarator and initializer. 3610 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3611 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3612 if (!IDecl) 3613 continue; 3614 QualType T = IDecl->getType(); 3615 3616 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3617 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3618 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3619 if (T->isDependentType()) { 3620 // If T is dependent, we should not require a complete type. 3621 // (RequireCompleteType shouldn't be called with dependent types.) 3622 // But we still can at least check if we've got an array of unspecified 3623 // size without an initializer. 3624 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3625 !IDecl->getInit()) { 3626 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3627 << T; 3628 IDecl->setInvalidDecl(); 3629 } 3630 } else if (!IDecl->isInvalidDecl()) { 3631 // If T is an incomplete array type with an initializer list that is 3632 // dependent on something, its size has not been fixed. We could attempt 3633 // to fix the size for such arrays, but we would still have to check 3634 // here for initializers containing a C++0x vararg expansion, e.g. 3635 // template <typename... Args> void f(Args... args) { 3636 // int vals[] = { args }; 3637 // } 3638 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3639 Expr *Init = IDecl->getInit(); 3640 if (IAT && Init && 3641 (Init->isTypeDependent() || Init->isValueDependent())) { 3642 // Check that the member type of the array is complete, at least. 3643 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3644 diag::err_typecheck_decl_incomplete_type)) 3645 IDecl->setInvalidDecl(); 3646 } else if (RequireCompleteType(IDecl->getLocation(), T, 3647 diag::err_typecheck_decl_incomplete_type)) 3648 IDecl->setInvalidDecl(); 3649 } 3650 } 3651 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3652 // object that has file scope without an initializer, and without a 3653 // storage-class specifier or with the storage-class specifier "static", 3654 // constitutes a tentative definition. Note: A tentative definition with 3655 // external linkage is valid (C99 6.2.2p5). 3656 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3657 if (const IncompleteArrayType *ArrayT 3658 = Context.getAsIncompleteArrayType(T)) { 3659 if (RequireCompleteType(IDecl->getLocation(), 3660 ArrayT->getElementType(), 3661 diag::err_illegal_decl_array_incomplete_type)) 3662 IDecl->setInvalidDecl(); 3663 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3664 // C99 6.9.2p3: If the declaration of an identifier for an object is 3665 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3666 // declared type shall not be an incomplete type. 3667 // NOTE: code such as the following 3668 // static struct s; 3669 // struct s { int a; }; 3670 // is accepted by gcc. Hence here we issue a warning instead of 3671 // an error and we do not invalidate the static declaration. 3672 // NOTE: to avoid multiple warnings, only check the first declaration. 3673 if (IDecl->getPreviousDeclaration() == 0) 3674 RequireCompleteType(IDecl->getLocation(), T, 3675 diag::ext_typecheck_decl_incomplete_type); 3676 } 3677 } 3678 } 3679 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3680 Decls.data(), Decls.size())); 3681} 3682 3683 3684/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3685/// to introduce parameters into function prototype scope. 3686Sema::DeclPtrTy 3687Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3688 const DeclSpec &DS = D.getDeclSpec(); 3689 3690 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3691 VarDecl::StorageClass StorageClass = VarDecl::None; 3692 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3693 StorageClass = VarDecl::Register; 3694 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3695 Diag(DS.getStorageClassSpecLoc(), 3696 diag::err_invalid_storage_class_in_func_decl); 3697 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3698 } 3699 3700 if (D.getDeclSpec().isThreadSpecified()) 3701 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3702 3703 DiagnoseFunctionSpecifiers(D); 3704 3705 // Check that there are no default arguments inside the type of this 3706 // parameter (C++ only). 3707 if (getLangOptions().CPlusPlus) 3708 CheckExtraCXXDefaultArguments(D); 3709 3710 DeclaratorInfo *DInfo = 0; 3711 TagDecl *OwnedDecl = 0; 3712 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3713 3714 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3715 // C++ [dcl.fct]p6: 3716 // Types shall not be defined in return or parameter types. 3717 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3718 << Context.getTypeDeclType(OwnedDecl); 3719 } 3720 3721 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3722 // Can this happen for params? We already checked that they don't conflict 3723 // among each other. Here they can only shadow globals, which is ok. 3724 IdentifierInfo *II = D.getIdentifier(); 3725 if (II) { 3726 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3727 if (PrevDecl->isTemplateParameter()) { 3728 // Maybe we will complain about the shadowed template parameter. 3729 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3730 // Just pretend that we didn't see the previous declaration. 3731 PrevDecl = 0; 3732 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3733 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3734 3735 // Recover by removing the name 3736 II = 0; 3737 D.SetIdentifier(0, D.getIdentifierLoc()); 3738 } 3739 } 3740 } 3741 3742 // Parameters can not be abstract class types. 3743 // For record types, this is done by the AbstractClassUsageDiagnoser once 3744 // the class has been completely parsed. 3745 if (!CurContext->isRecord() && 3746 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3747 diag::err_abstract_type_in_decl, 3748 AbstractParamType)) 3749 D.setInvalidType(true); 3750 3751 QualType T = adjustParameterType(parmDeclType); 3752 3753 ParmVarDecl *New 3754 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3755 T, DInfo, StorageClass, 0); 3756 3757 if (D.isInvalidType()) 3758 New->setInvalidDecl(); 3759 3760 // Parameter declarators cannot be interface types. All ObjC objects are 3761 // passed by reference. 3762 if (T->isObjCInterfaceType()) { 3763 Diag(D.getIdentifierLoc(), 3764 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3765 New->setInvalidDecl(); 3766 } 3767 3768 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3769 if (D.getCXXScopeSpec().isSet()) { 3770 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3771 << D.getCXXScopeSpec().getRange(); 3772 New->setInvalidDecl(); 3773 } 3774 3775 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3776 // duration shall not be qualified by an address-space qualifier." 3777 // Since all parameters have automatic store duration, they can not have 3778 // an address space. 3779 if (T.getAddressSpace() != 0) { 3780 Diag(D.getIdentifierLoc(), 3781 diag::err_arg_with_address_space); 3782 New->setInvalidDecl(); 3783 } 3784 3785 3786 // Add the parameter declaration into this scope. 3787 S->AddDecl(DeclPtrTy::make(New)); 3788 if (II) 3789 IdResolver.AddDecl(New); 3790 3791 ProcessDeclAttributes(S, New, D); 3792 3793 if (New->hasAttr<BlocksAttr>()) { 3794 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3795 } 3796 return DeclPtrTy::make(New); 3797} 3798 3799void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3800 SourceLocation LocAfterDecls) { 3801 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3802 "Not a function declarator!"); 3803 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3804 3805 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3806 // for a K&R function. 3807 if (!FTI.hasPrototype) { 3808 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3809 --i; 3810 if (FTI.ArgInfo[i].Param == 0) { 3811 llvm::SmallString<256> Code; 3812 llvm::raw_svector_ostream(Code) << " int " 3813 << FTI.ArgInfo[i].Ident->getName() 3814 << ";\n"; 3815 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3816 << FTI.ArgInfo[i].Ident 3817 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3818 3819 // Implicitly declare the argument as type 'int' for lack of a better 3820 // type. 3821 DeclSpec DS; 3822 const char* PrevSpec; // unused 3823 unsigned DiagID; // unused 3824 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3825 PrevSpec, DiagID); 3826 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3827 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3828 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3829 } 3830 } 3831 } 3832} 3833 3834Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3835 Declarator &D) { 3836 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3837 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3838 "Not a function declarator!"); 3839 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3840 3841 if (FTI.hasPrototype) { 3842 // FIXME: Diagnose arguments without names in C. 3843 } 3844 3845 Scope *ParentScope = FnBodyScope->getParent(); 3846 3847 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3848 MultiTemplateParamsArg(*this), 3849 /*IsFunctionDefinition=*/true); 3850 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3851} 3852 3853Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3854 // Clear the last template instantiation error context. 3855 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 3856 3857 if (!D) 3858 return D; 3859 FunctionDecl *FD = 0; 3860 3861 if (FunctionTemplateDecl *FunTmpl 3862 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3863 FD = FunTmpl->getTemplatedDecl(); 3864 else 3865 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3866 3867 CurFunctionNeedsScopeChecking = false; 3868 3869 // See if this is a redefinition. 3870 const FunctionDecl *Definition; 3871 if (FD->getBody(Definition)) { 3872 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3873 Diag(Definition->getLocation(), diag::note_previous_definition); 3874 } 3875 3876 // Builtin functions cannot be defined. 3877 if (unsigned BuiltinID = FD->getBuiltinID()) { 3878 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3879 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3880 FD->setInvalidDecl(); 3881 } 3882 } 3883 3884 // The return type of a function definition must be complete 3885 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3886 QualType ResultType = FD->getResultType(); 3887 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3888 !FD->isInvalidDecl() && 3889 RequireCompleteType(FD->getLocation(), ResultType, 3890 diag::err_func_def_incomplete_result)) 3891 FD->setInvalidDecl(); 3892 3893 // GNU warning -Wmissing-prototypes: 3894 // Warn if a global function is defined without a previous 3895 // prototype declaration. This warning is issued even if the 3896 // definition itself provides a prototype. The aim is to detect 3897 // global functions that fail to be declared in header files. 3898 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3899 !FD->isMain()) { 3900 bool MissingPrototype = true; 3901 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3902 Prev; Prev = Prev->getPreviousDeclaration()) { 3903 // Ignore any declarations that occur in function or method 3904 // scope, because they aren't visible from the header. 3905 if (Prev->getDeclContext()->isFunctionOrMethod()) 3906 continue; 3907 3908 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3909 break; 3910 } 3911 3912 if (MissingPrototype) 3913 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3914 } 3915 3916 if (FnBodyScope) 3917 PushDeclContext(FnBodyScope, FD); 3918 3919 // Check the validity of our function parameters 3920 CheckParmsForFunctionDef(FD); 3921 3922 // Introduce our parameters into the function scope 3923 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3924 ParmVarDecl *Param = FD->getParamDecl(p); 3925 Param->setOwningFunction(FD); 3926 3927 // If this has an identifier, add it to the scope stack. 3928 if (Param->getIdentifier() && FnBodyScope) 3929 PushOnScopeChains(Param, FnBodyScope); 3930 } 3931 3932 // Checking attributes of current function definition 3933 // dllimport attribute. 3934 if (FD->getAttr<DLLImportAttr>() && 3935 (!FD->getAttr<DLLExportAttr>())) { 3936 // dllimport attribute cannot be applied to definition. 3937 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3938 Diag(FD->getLocation(), 3939 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3940 << "dllimport"; 3941 FD->setInvalidDecl(); 3942 return DeclPtrTy::make(FD); 3943 } else { 3944 // If a symbol previously declared dllimport is later defined, the 3945 // attribute is ignored in subsequent references, and a warning is 3946 // emitted. 3947 Diag(FD->getLocation(), 3948 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3949 << FD->getNameAsCString() << "dllimport"; 3950 } 3951 } 3952 return DeclPtrTy::make(FD); 3953} 3954 3955Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3956 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3957} 3958 3959Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3960 bool IsInstantiation) { 3961 Decl *dcl = D.getAs<Decl>(); 3962 Stmt *Body = BodyArg.takeAs<Stmt>(); 3963 3964 FunctionDecl *FD = 0; 3965 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3966 if (FunTmpl) 3967 FD = FunTmpl->getTemplatedDecl(); 3968 else 3969 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3970 3971 if (FD) { 3972 FD->setBody(Body); 3973 if (FD->isMain()) 3974 // C and C++ allow for main to automagically return 0. 3975 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3976 FD->setHasImplicitReturnZero(true); 3977 else 3978 CheckFallThroughForFunctionDef(FD, Body); 3979 3980 if (!FD->isInvalidDecl()) 3981 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3982 3983 // C++ [basic.def.odr]p2: 3984 // [...] A virtual member function is used if it is not pure. [...] 3985 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3986 if (Method->isVirtual() && !Method->isPure()) 3987 MarkDeclarationReferenced(Method->getLocation(), Method); 3988 3989 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3990 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3991 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3992 MD->setBody(Body); 3993 CheckFallThroughForFunctionDef(MD, Body); 3994 MD->setEndLoc(Body->getLocEnd()); 3995 3996 if (!MD->isInvalidDecl()) 3997 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3998 } else { 3999 Body->Destroy(Context); 4000 return DeclPtrTy(); 4001 } 4002 if (!IsInstantiation) 4003 PopDeclContext(); 4004 4005 // Verify and clean out per-function state. 4006 4007 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4008 4009 // Check goto/label use. 4010 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4011 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4012 LabelStmt *L = I->second; 4013 4014 // Verify that we have no forward references left. If so, there was a goto 4015 // or address of a label taken, but no definition of it. Label fwd 4016 // definitions are indicated with a null substmt. 4017 if (L->getSubStmt() != 0) 4018 continue; 4019 4020 // Emit error. 4021 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4022 4023 // At this point, we have gotos that use the bogus label. Stitch it into 4024 // the function body so that they aren't leaked and that the AST is well 4025 // formed. 4026 if (Body == 0) { 4027 // The whole function wasn't parsed correctly, just delete this. 4028 L->Destroy(Context); 4029 continue; 4030 } 4031 4032 // Otherwise, the body is valid: we want to stitch the label decl into the 4033 // function somewhere so that it is properly owned and so that the goto 4034 // has a valid target. Do this by creating a new compound stmt with the 4035 // label in it. 4036 4037 // Give the label a sub-statement. 4038 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4039 4040 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4041 cast<CXXTryStmt>(Body)->getTryBlock() : 4042 cast<CompoundStmt>(Body); 4043 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4044 Elements.push_back(L); 4045 Compound->setStmts(Context, &Elements[0], Elements.size()); 4046 } 4047 FunctionLabelMap.clear(); 4048 4049 if (!Body) return D; 4050 4051 // Verify that that gotos and switch cases don't jump into scopes illegally. 4052 if (CurFunctionNeedsScopeChecking) 4053 DiagnoseInvalidJumps(Body); 4054 4055 // C++ constructors that have function-try-blocks can't have return 4056 // statements in the handlers of that block. (C++ [except.handle]p14) 4057 // Verify this. 4058 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4059 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4060 4061 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4062 MarkBaseAndMemberDestructorsReferenced(Destructor); 4063 4064 // If any errors have occurred, clear out any temporaries that may have 4065 // been leftover. This ensures that these temporaries won't be picked up for 4066 // deletion in some later function. 4067 if (PP.getDiagnostics().hasErrorOccurred()) 4068 ExprTemporaries.clear(); 4069 4070 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4071 return D; 4072} 4073 4074/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4075/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4076NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4077 IdentifierInfo &II, Scope *S) { 4078 // Before we produce a declaration for an implicitly defined 4079 // function, see whether there was a locally-scoped declaration of 4080 // this name as a function or variable. If so, use that 4081 // (non-visible) declaration, and complain about it. 4082 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4083 = LocallyScopedExternalDecls.find(&II); 4084 if (Pos != LocallyScopedExternalDecls.end()) { 4085 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4086 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4087 return Pos->second; 4088 } 4089 4090 // Extension in C99. Legal in C90, but warn about it. 4091 if (II.getName().startswith("__builtin_")) 4092 Diag(Loc, diag::warn_builtin_unknown) << &II; 4093 else if (getLangOptions().C99) 4094 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4095 else 4096 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4097 4098 // Set a Declarator for the implicit definition: int foo(); 4099 const char *Dummy; 4100 DeclSpec DS; 4101 unsigned DiagID; 4102 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4103 Error = Error; // Silence warning. 4104 assert(!Error && "Error setting up implicit decl!"); 4105 Declarator D(DS, Declarator::BlockContext); 4106 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4107 0, 0, false, SourceLocation(), 4108 false, 0,0,0, Loc, Loc, D), 4109 SourceLocation()); 4110 D.SetIdentifier(&II, Loc); 4111 4112 // Insert this function into translation-unit scope. 4113 4114 DeclContext *PrevDC = CurContext; 4115 CurContext = Context.getTranslationUnitDecl(); 4116 4117 FunctionDecl *FD = 4118 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4119 FD->setImplicit(); 4120 4121 CurContext = PrevDC; 4122 4123 AddKnownFunctionAttributes(FD); 4124 4125 return FD; 4126} 4127 4128/// \brief Adds any function attributes that we know a priori based on 4129/// the declaration of this function. 4130/// 4131/// These attributes can apply both to implicitly-declared builtins 4132/// (like __builtin___printf_chk) or to library-declared functions 4133/// like NSLog or printf. 4134void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4135 if (FD->isInvalidDecl()) 4136 return; 4137 4138 // If this is a built-in function, map its builtin attributes to 4139 // actual attributes. 4140 if (unsigned BuiltinID = FD->getBuiltinID()) { 4141 // Handle printf-formatting attributes. 4142 unsigned FormatIdx; 4143 bool HasVAListArg; 4144 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4145 if (!FD->getAttr<FormatAttr>()) 4146 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4147 HasVAListArg ? 0 : FormatIdx + 2)); 4148 } 4149 4150 // Mark const if we don't care about errno and that is the only 4151 // thing preventing the function from being const. This allows 4152 // IRgen to use LLVM intrinsics for such functions. 4153 if (!getLangOptions().MathErrno && 4154 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4155 if (!FD->getAttr<ConstAttr>()) 4156 FD->addAttr(::new (Context) ConstAttr()); 4157 } 4158 4159 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4160 FD->addAttr(::new (Context) NoReturnAttr()); 4161 } 4162 4163 IdentifierInfo *Name = FD->getIdentifier(); 4164 if (!Name) 4165 return; 4166 if ((!getLangOptions().CPlusPlus && 4167 FD->getDeclContext()->isTranslationUnit()) || 4168 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4169 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4170 LinkageSpecDecl::lang_c)) { 4171 // Okay: this could be a libc/libm/Objective-C function we know 4172 // about. 4173 } else 4174 return; 4175 4176 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4177 // FIXME: NSLog and NSLogv should be target specific 4178 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4179 // FIXME: We known better than our headers. 4180 const_cast<FormatAttr *>(Format)->setType("printf"); 4181 } else 4182 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4183 Name->isStr("NSLogv") ? 0 : 2)); 4184 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4185 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4186 // target-specific builtins, perhaps? 4187 if (!FD->getAttr<FormatAttr>()) 4188 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4189 Name->isStr("vasprintf") ? 0 : 3)); 4190 } 4191} 4192 4193TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4194 DeclaratorInfo *DInfo) { 4195 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4196 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4197 4198 if (!DInfo) { 4199 assert(D.isInvalidType() && "no declarator info for valid type"); 4200 DInfo = Context.getTrivialDeclaratorInfo(T); 4201 } 4202 4203 // Scope manipulation handled by caller. 4204 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4205 D.getIdentifierLoc(), 4206 D.getIdentifier(), 4207 DInfo); 4208 4209 if (const TagType *TT = T->getAs<TagType>()) { 4210 TagDecl *TD = TT->getDecl(); 4211 4212 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4213 // keep track of the TypedefDecl. 4214 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4215 TD->setTypedefForAnonDecl(NewTD); 4216 } 4217 4218 if (D.isInvalidType()) 4219 NewTD->setInvalidDecl(); 4220 return NewTD; 4221} 4222 4223 4224/// \brief Determine whether a tag with a given kind is acceptable 4225/// as a redeclaration of the given tag declaration. 4226/// 4227/// \returns true if the new tag kind is acceptable, false otherwise. 4228bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4229 TagDecl::TagKind NewTag, 4230 SourceLocation NewTagLoc, 4231 const IdentifierInfo &Name) { 4232 // C++ [dcl.type.elab]p3: 4233 // The class-key or enum keyword present in the 4234 // elaborated-type-specifier shall agree in kind with the 4235 // declaration to which the name in theelaborated-type-specifier 4236 // refers. This rule also applies to the form of 4237 // elaborated-type-specifier that declares a class-name or 4238 // friend class since it can be construed as referring to the 4239 // definition of the class. Thus, in any 4240 // elaborated-type-specifier, the enum keyword shall be used to 4241 // refer to an enumeration (7.2), the union class-keyshall be 4242 // used to refer to a union (clause 9), and either the class or 4243 // struct class-key shall be used to refer to a class (clause 9) 4244 // declared using the class or struct class-key. 4245 TagDecl::TagKind OldTag = Previous->getTagKind(); 4246 if (OldTag == NewTag) 4247 return true; 4248 4249 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4250 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4251 // Warn about the struct/class tag mismatch. 4252 bool isTemplate = false; 4253 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4254 isTemplate = Record->getDescribedClassTemplate(); 4255 4256 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4257 << (NewTag == TagDecl::TK_class) 4258 << isTemplate << &Name 4259 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4260 OldTag == TagDecl::TK_class? "class" : "struct"); 4261 Diag(Previous->getLocation(), diag::note_previous_use); 4262 return true; 4263 } 4264 return false; 4265} 4266 4267/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4268/// former case, Name will be non-null. In the later case, Name will be null. 4269/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4270/// reference/declaration/definition of a tag. 4271Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4272 SourceLocation KWLoc, const CXXScopeSpec &SS, 4273 IdentifierInfo *Name, SourceLocation NameLoc, 4274 AttributeList *Attr, AccessSpecifier AS, 4275 MultiTemplateParamsArg TemplateParameterLists, 4276 bool &OwnedDecl, bool &IsDependent) { 4277 // If this is not a definition, it must have a name. 4278 assert((Name != 0 || TUK == TUK_Definition) && 4279 "Nameless record must be a definition!"); 4280 4281 OwnedDecl = false; 4282 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4283 4284 // FIXME: Check explicit specializations more carefully. 4285 bool isExplicitSpecialization = false; 4286 if (TUK != TUK_Reference) { 4287 if (TemplateParameterList *TemplateParams 4288 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4289 (TemplateParameterList**)TemplateParameterLists.get(), 4290 TemplateParameterLists.size(), 4291 isExplicitSpecialization)) { 4292 if (TemplateParams->size() > 0) { 4293 // This is a declaration or definition of a class template (which may 4294 // be a member of another template). 4295 OwnedDecl = false; 4296 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4297 SS, Name, NameLoc, Attr, 4298 TemplateParams, 4299 AS); 4300 TemplateParameterLists.release(); 4301 return Result.get(); 4302 } else { 4303 // The "template<>" header is extraneous. 4304 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4305 << ElaboratedType::getNameForTagKind(Kind) << Name; 4306 isExplicitSpecialization = true; 4307 } 4308 } 4309 4310 TemplateParameterLists.release(); 4311 } 4312 4313 DeclContext *SearchDC = CurContext; 4314 DeclContext *DC = CurContext; 4315 NamedDecl *PrevDecl = 0; 4316 bool isStdBadAlloc = false; 4317 bool Invalid = false; 4318 4319 LookupResult::RedeclarationKind Redecl = 4320 (LookupResult::RedeclarationKind) (TUK != TUK_Reference); 4321 4322 if (Name && SS.isNotEmpty()) { 4323 // We have a nested-name tag ('struct foo::bar'). 4324 4325 // Check for invalid 'foo::'. 4326 if (SS.isInvalid()) { 4327 Name = 0; 4328 goto CreateNewDecl; 4329 } 4330 4331 // If this is a friend or a reference to a class in a dependent 4332 // context, don't try to make a decl for it. 4333 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4334 DC = computeDeclContext(SS, false); 4335 if (!DC) { 4336 IsDependent = true; 4337 return DeclPtrTy(); 4338 } 4339 } 4340 4341 if (RequireCompleteDeclContext(SS)) 4342 return DeclPtrTy::make((Decl *)0); 4343 4344 DC = computeDeclContext(SS, true); 4345 SearchDC = DC; 4346 // Look-up name inside 'foo::'. 4347 LookupResult R(*this, Name, NameLoc, LookupTagName, Redecl); 4348 LookupQualifiedName(R, DC); 4349 4350 if (R.isAmbiguous()) 4351 return DeclPtrTy(); 4352 4353 if (R.getResultKind() == LookupResult::Found) 4354 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4355 4356 // A tag 'foo::bar' must already exist. 4357 if (!PrevDecl) { 4358 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4359 Name = 0; 4360 Invalid = true; 4361 goto CreateNewDecl; 4362 } 4363 } else if (Name) { 4364 // If this is a named struct, check to see if there was a previous forward 4365 // declaration or definition. 4366 // FIXME: We're looking into outer scopes here, even when we 4367 // shouldn't be. Doing so can result in ambiguities that we 4368 // shouldn't be diagnosing. 4369 LookupResult R(*this, Name, NameLoc, LookupTagName, Redecl); 4370 LookupName(R, S); 4371 if (R.isAmbiguous()) { 4372 // FIXME: This is not best way to recover from case like: 4373 // 4374 // struct S s; 4375 // 4376 // causes needless "incomplete type" error later. 4377 Name = 0; 4378 PrevDecl = 0; 4379 Invalid = true; 4380 } else 4381 PrevDecl = R.getAsSingleDecl(Context); 4382 4383 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4384 // FIXME: This makes sure that we ignore the contexts associated 4385 // with C structs, unions, and enums when looking for a matching 4386 // tag declaration or definition. See the similar lookup tweak 4387 // in Sema::LookupName; is there a better way to deal with this? 4388 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4389 SearchDC = SearchDC->getParent(); 4390 } 4391 } 4392 4393 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4394 // Maybe we will complain about the shadowed template parameter. 4395 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4396 // Just pretend that we didn't see the previous declaration. 4397 PrevDecl = 0; 4398 } 4399 4400 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4401 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4402 // This is a declaration of or a reference to "std::bad_alloc". 4403 isStdBadAlloc = true; 4404 4405 if (!PrevDecl && StdBadAlloc) { 4406 // std::bad_alloc has been implicitly declared (but made invisible to 4407 // name lookup). Fill in this implicit declaration as the previous 4408 // declaration, so that the declarations get chained appropriately. 4409 PrevDecl = StdBadAlloc; 4410 } 4411 } 4412 4413 if (PrevDecl) { 4414 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4415 // If this is a use of a previous tag, or if the tag is already declared 4416 // in the same scope (so that the definition/declaration completes or 4417 // rementions the tag), reuse the decl. 4418 if (TUK == TUK_Reference || TUK == TUK_Friend || 4419 isDeclInScope(PrevDecl, SearchDC, S)) { 4420 // Make sure that this wasn't declared as an enum and now used as a 4421 // struct or something similar. 4422 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4423 bool SafeToContinue 4424 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4425 Kind != TagDecl::TK_enum); 4426 if (SafeToContinue) 4427 Diag(KWLoc, diag::err_use_with_wrong_tag) 4428 << Name 4429 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4430 PrevTagDecl->getKindName()); 4431 else 4432 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4433 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4434 4435 if (SafeToContinue) 4436 Kind = PrevTagDecl->getTagKind(); 4437 else { 4438 // Recover by making this an anonymous redefinition. 4439 Name = 0; 4440 PrevDecl = 0; 4441 Invalid = true; 4442 } 4443 } 4444 4445 if (!Invalid) { 4446 // If this is a use, just return the declaration we found. 4447 4448 // FIXME: In the future, return a variant or some other clue 4449 // for the consumer of this Decl to know it doesn't own it. 4450 // For our current ASTs this shouldn't be a problem, but will 4451 // need to be changed with DeclGroups. 4452 if (TUK == TUK_Reference || TUK == TUK_Friend) 4453 return DeclPtrTy::make(PrevDecl); 4454 4455 // Diagnose attempts to redefine a tag. 4456 if (TUK == TUK_Definition) { 4457 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4458 // If we're defining a specialization and the previous definition 4459 // is from an implicit instantiation, don't emit an error 4460 // here; we'll catch this in the general case below. 4461 if (!isExplicitSpecialization || 4462 !isa<CXXRecordDecl>(Def) || 4463 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4464 == TSK_ExplicitSpecialization) { 4465 Diag(NameLoc, diag::err_redefinition) << Name; 4466 Diag(Def->getLocation(), diag::note_previous_definition); 4467 // If this is a redefinition, recover by making this 4468 // struct be anonymous, which will make any later 4469 // references get the previous definition. 4470 Name = 0; 4471 PrevDecl = 0; 4472 Invalid = true; 4473 } 4474 } else { 4475 // If the type is currently being defined, complain 4476 // about a nested redefinition. 4477 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4478 if (Tag->isBeingDefined()) { 4479 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4480 Diag(PrevTagDecl->getLocation(), 4481 diag::note_previous_definition); 4482 Name = 0; 4483 PrevDecl = 0; 4484 Invalid = true; 4485 } 4486 } 4487 4488 // Okay, this is definition of a previously declared or referenced 4489 // tag PrevDecl. We're going to create a new Decl for it. 4490 } 4491 } 4492 // If we get here we have (another) forward declaration or we 4493 // have a definition. Just create a new decl. 4494 4495 } else { 4496 // If we get here, this is a definition of a new tag type in a nested 4497 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4498 // new decl/type. We set PrevDecl to NULL so that the entities 4499 // have distinct types. 4500 PrevDecl = 0; 4501 } 4502 // If we get here, we're going to create a new Decl. If PrevDecl 4503 // is non-NULL, it's a definition of the tag declared by 4504 // PrevDecl. If it's NULL, we have a new definition. 4505 } else { 4506 // PrevDecl is a namespace, template, or anything else 4507 // that lives in the IDNS_Tag identifier namespace. 4508 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4509 // The tag name clashes with a namespace name, issue an error and 4510 // recover by making this tag be anonymous. 4511 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4512 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4513 Name = 0; 4514 PrevDecl = 0; 4515 Invalid = true; 4516 } else { 4517 // The existing declaration isn't relevant to us; we're in a 4518 // new scope, so clear out the previous declaration. 4519 PrevDecl = 0; 4520 } 4521 } 4522 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4523 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4524 // C++ [basic.scope.pdecl]p5: 4525 // -- for an elaborated-type-specifier of the form 4526 // 4527 // class-key identifier 4528 // 4529 // if the elaborated-type-specifier is used in the 4530 // decl-specifier-seq or parameter-declaration-clause of a 4531 // function defined in namespace scope, the identifier is 4532 // declared as a class-name in the namespace that contains 4533 // the declaration; otherwise, except as a friend 4534 // declaration, the identifier is declared in the smallest 4535 // non-class, non-function-prototype scope that contains the 4536 // declaration. 4537 // 4538 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4539 // C structs and unions. 4540 // 4541 // GNU C also supports this behavior as part of its incomplete 4542 // enum types extension, while GNU C++ does not. 4543 // 4544 // Find the context where we'll be declaring the tag. 4545 // FIXME: We would like to maintain the current DeclContext as the 4546 // lexical context, 4547 while (SearchDC->isRecord()) 4548 SearchDC = SearchDC->getParent(); 4549 4550 // Find the scope where we'll be declaring the tag. 4551 while (S->isClassScope() || 4552 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4553 ((S->getFlags() & Scope::DeclScope) == 0) || 4554 (S->getEntity() && 4555 ((DeclContext *)S->getEntity())->isTransparentContext())) 4556 S = S->getParent(); 4557 4558 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4559 // C++ [namespace.memdef]p3: 4560 // If a friend declaration in a non-local class first declares a 4561 // class or function, the friend class or function is a member of 4562 // the innermost enclosing namespace. 4563 while (!SearchDC->isFileContext()) 4564 SearchDC = SearchDC->getParent(); 4565 4566 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4567 while (S->getEntity() != SearchDC) 4568 S = S->getParent(); 4569 } 4570 4571CreateNewDecl: 4572 4573 // If there is an identifier, use the location of the identifier as the 4574 // location of the decl, otherwise use the location of the struct/union 4575 // keyword. 4576 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4577 4578 // Otherwise, create a new declaration. If there is a previous 4579 // declaration of the same entity, the two will be linked via 4580 // PrevDecl. 4581 TagDecl *New; 4582 4583 if (Kind == TagDecl::TK_enum) { 4584 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4585 // enum X { A, B, C } D; D should chain to X. 4586 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4587 cast_or_null<EnumDecl>(PrevDecl)); 4588 // If this is an undefined enum, warn. 4589 if (TUK != TUK_Definition && !Invalid) { 4590 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4591 : diag::ext_forward_ref_enum; 4592 Diag(Loc, DK); 4593 } 4594 } else { 4595 // struct/union/class 4596 4597 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4598 // struct X { int A; } D; D should chain to X. 4599 if (getLangOptions().CPlusPlus) { 4600 // FIXME: Look for a way to use RecordDecl for simple structs. 4601 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4602 cast_or_null<CXXRecordDecl>(PrevDecl)); 4603 4604 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4605 StdBadAlloc = cast<CXXRecordDecl>(New); 4606 } else 4607 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4608 cast_or_null<RecordDecl>(PrevDecl)); 4609 } 4610 4611 if (Kind != TagDecl::TK_enum) { 4612 // Handle #pragma pack: if the #pragma pack stack has non-default 4613 // alignment, make up a packed attribute for this decl. These 4614 // attributes are checked when the ASTContext lays out the 4615 // structure. 4616 // 4617 // It is important for implementing the correct semantics that this 4618 // happen here (in act on tag decl). The #pragma pack stack is 4619 // maintained as a result of parser callbacks which can occur at 4620 // many points during the parsing of a struct declaration (because 4621 // the #pragma tokens are effectively skipped over during the 4622 // parsing of the struct). 4623 if (unsigned Alignment = getPragmaPackAlignment()) 4624 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4625 } 4626 4627 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4628 // C++ [dcl.typedef]p3: 4629 // [...] Similarly, in a given scope, a class or enumeration 4630 // shall not be declared with the same name as a typedef-name 4631 // that is declared in that scope and refers to a type other 4632 // than the class or enumeration itself. 4633 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4634 LookupResult::ForRedeclaration); 4635 LookupName(Lookup, S); 4636 TypedefDecl *PrevTypedef = 0; 4637 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4638 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4639 4640 NamedDecl *PrevTypedefNamed = PrevTypedef; 4641 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4642 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4643 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4644 Diag(Loc, diag::err_tag_definition_of_typedef) 4645 << Context.getTypeDeclType(New) 4646 << PrevTypedef->getUnderlyingType(); 4647 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4648 Invalid = true; 4649 } 4650 } 4651 4652 // If this is a specialization of a member class (of a class template), 4653 // check the specialization. 4654 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4655 Invalid = true; 4656 4657 if (Invalid) 4658 New->setInvalidDecl(); 4659 4660 if (Attr) 4661 ProcessDeclAttributeList(S, New, Attr); 4662 4663 // If we're declaring or defining a tag in function prototype scope 4664 // in C, note that this type can only be used within the function. 4665 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4666 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4667 4668 // Set the lexical context. If the tag has a C++ scope specifier, the 4669 // lexical context will be different from the semantic context. 4670 New->setLexicalDeclContext(CurContext); 4671 4672 // Mark this as a friend decl if applicable. 4673 if (TUK == TUK_Friend) 4674 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4675 4676 // Set the access specifier. 4677 if (!Invalid && TUK != TUK_Friend) 4678 SetMemberAccessSpecifier(New, PrevDecl, AS); 4679 4680 if (TUK == TUK_Definition) 4681 New->startDefinition(); 4682 4683 // If this has an identifier, add it to the scope stack. 4684 if (TUK == TUK_Friend) { 4685 // We might be replacing an existing declaration in the lookup tables; 4686 // if so, borrow its access specifier. 4687 if (PrevDecl) 4688 New->setAccess(PrevDecl->getAccess()); 4689 4690 // Friend tag decls are visible in fairly strange ways. 4691 if (!CurContext->isDependentContext()) { 4692 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4693 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4694 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4695 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4696 } 4697 } else if (Name) { 4698 S = getNonFieldDeclScope(S); 4699 PushOnScopeChains(New, S); 4700 } else { 4701 CurContext->addDecl(New); 4702 } 4703 4704 // If this is the C FILE type, notify the AST context. 4705 if (IdentifierInfo *II = New->getIdentifier()) 4706 if (!New->isInvalidDecl() && 4707 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4708 II->isStr("FILE")) 4709 Context.setFILEDecl(New); 4710 4711 OwnedDecl = true; 4712 return DeclPtrTy::make(New); 4713} 4714 4715void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4716 AdjustDeclIfTemplate(TagD); 4717 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4718 4719 // Enter the tag context. 4720 PushDeclContext(S, Tag); 4721 4722 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4723 FieldCollector->StartClass(); 4724 4725 if (Record->getIdentifier()) { 4726 // C++ [class]p2: 4727 // [...] The class-name is also inserted into the scope of the 4728 // class itself; this is known as the injected-class-name. For 4729 // purposes of access checking, the injected-class-name is treated 4730 // as if it were a public member name. 4731 CXXRecordDecl *InjectedClassName 4732 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4733 CurContext, Record->getLocation(), 4734 Record->getIdentifier(), 4735 Record->getTagKeywordLoc(), 4736 Record); 4737 InjectedClassName->setImplicit(); 4738 InjectedClassName->setAccess(AS_public); 4739 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4740 InjectedClassName->setDescribedClassTemplate(Template); 4741 PushOnScopeChains(InjectedClassName, S); 4742 assert(InjectedClassName->isInjectedClassName() && 4743 "Broken injected-class-name"); 4744 } 4745 } 4746} 4747 4748void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4749 SourceLocation RBraceLoc) { 4750 AdjustDeclIfTemplate(TagD); 4751 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4752 Tag->setRBraceLoc(RBraceLoc); 4753 4754 if (isa<CXXRecordDecl>(Tag)) 4755 FieldCollector->FinishClass(); 4756 4757 // Exit this scope of this tag's definition. 4758 PopDeclContext(); 4759 4760 // Notify the consumer that we've defined a tag. 4761 Consumer.HandleTagDeclDefinition(Tag); 4762} 4763 4764// Note that FieldName may be null for anonymous bitfields. 4765bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4766 QualType FieldTy, const Expr *BitWidth, 4767 bool *ZeroWidth) { 4768 // Default to true; that shouldn't confuse checks for emptiness 4769 if (ZeroWidth) 4770 *ZeroWidth = true; 4771 4772 // C99 6.7.2.1p4 - verify the field type. 4773 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4774 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4775 // Handle incomplete types with specific error. 4776 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4777 return true; 4778 if (FieldName) 4779 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4780 << FieldName << FieldTy << BitWidth->getSourceRange(); 4781 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4782 << FieldTy << BitWidth->getSourceRange(); 4783 } 4784 4785 // If the bit-width is type- or value-dependent, don't try to check 4786 // it now. 4787 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4788 return false; 4789 4790 llvm::APSInt Value; 4791 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4792 return true; 4793 4794 if (Value != 0 && ZeroWidth) 4795 *ZeroWidth = false; 4796 4797 // Zero-width bitfield is ok for anonymous field. 4798 if (Value == 0 && FieldName) 4799 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4800 4801 if (Value.isSigned() && Value.isNegative()) { 4802 if (FieldName) 4803 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4804 << FieldName << Value.toString(10); 4805 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4806 << Value.toString(10); 4807 } 4808 4809 if (!FieldTy->isDependentType()) { 4810 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4811 if (Value.getZExtValue() > TypeSize) { 4812 if (FieldName) 4813 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4814 << FieldName << (unsigned)TypeSize; 4815 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4816 << (unsigned)TypeSize; 4817 } 4818 } 4819 4820 return false; 4821} 4822 4823/// ActOnField - Each field of a struct/union/class is passed into this in order 4824/// to create a FieldDecl object for it. 4825Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4826 SourceLocation DeclStart, 4827 Declarator &D, ExprTy *BitfieldWidth) { 4828 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4829 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4830 AS_public); 4831 return DeclPtrTy::make(Res); 4832} 4833 4834/// HandleField - Analyze a field of a C struct or a C++ data member. 4835/// 4836FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4837 SourceLocation DeclStart, 4838 Declarator &D, Expr *BitWidth, 4839 AccessSpecifier AS) { 4840 IdentifierInfo *II = D.getIdentifier(); 4841 SourceLocation Loc = DeclStart; 4842 if (II) Loc = D.getIdentifierLoc(); 4843 4844 DeclaratorInfo *DInfo = 0; 4845 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4846 if (getLangOptions().CPlusPlus) 4847 CheckExtraCXXDefaultArguments(D); 4848 4849 DiagnoseFunctionSpecifiers(D); 4850 4851 if (D.getDeclSpec().isThreadSpecified()) 4852 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4853 4854 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 4855 LookupResult::ForRedeclaration); 4856 4857 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4858 // Maybe we will complain about the shadowed template parameter. 4859 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4860 // Just pretend that we didn't see the previous declaration. 4861 PrevDecl = 0; 4862 } 4863 4864 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4865 PrevDecl = 0; 4866 4867 bool Mutable 4868 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4869 SourceLocation TSSL = D.getSourceRange().getBegin(); 4870 FieldDecl *NewFD 4871 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4872 AS, PrevDecl, &D); 4873 if (NewFD->isInvalidDecl() && PrevDecl) { 4874 // Don't introduce NewFD into scope; there's already something 4875 // with the same name in the same scope. 4876 } else if (II) { 4877 PushOnScopeChains(NewFD, S); 4878 } else 4879 Record->addDecl(NewFD); 4880 4881 return NewFD; 4882} 4883 4884/// \brief Build a new FieldDecl and check its well-formedness. 4885/// 4886/// This routine builds a new FieldDecl given the fields name, type, 4887/// record, etc. \p PrevDecl should refer to any previous declaration 4888/// with the same name and in the same scope as the field to be 4889/// created. 4890/// 4891/// \returns a new FieldDecl. 4892/// 4893/// \todo The Declarator argument is a hack. It will be removed once 4894FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4895 DeclaratorInfo *DInfo, 4896 RecordDecl *Record, SourceLocation Loc, 4897 bool Mutable, Expr *BitWidth, 4898 SourceLocation TSSL, 4899 AccessSpecifier AS, NamedDecl *PrevDecl, 4900 Declarator *D) { 4901 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4902 bool InvalidDecl = false; 4903 if (D) InvalidDecl = D->isInvalidType(); 4904 4905 // If we receive a broken type, recover by assuming 'int' and 4906 // marking this declaration as invalid. 4907 if (T.isNull()) { 4908 InvalidDecl = true; 4909 T = Context.IntTy; 4910 } 4911 4912 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4913 // than a variably modified type. 4914 if (T->isVariablyModifiedType()) { 4915 bool SizeIsNegative; 4916 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4917 SizeIsNegative); 4918 if (!FixedTy.isNull()) { 4919 Diag(Loc, diag::warn_illegal_constant_array_size); 4920 T = FixedTy; 4921 } else { 4922 if (SizeIsNegative) 4923 Diag(Loc, diag::err_typecheck_negative_array_size); 4924 else 4925 Diag(Loc, diag::err_typecheck_field_variable_size); 4926 InvalidDecl = true; 4927 } 4928 } 4929 4930 // Fields can not have abstract class types 4931 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4932 AbstractFieldType)) 4933 InvalidDecl = true; 4934 4935 bool ZeroWidth = false; 4936 // If this is declared as a bit-field, check the bit-field. 4937 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4938 InvalidDecl = true; 4939 DeleteExpr(BitWidth); 4940 BitWidth = 0; 4941 ZeroWidth = false; 4942 } 4943 4944 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4945 BitWidth, Mutable); 4946 if (InvalidDecl) 4947 NewFD->setInvalidDecl(); 4948 4949 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4950 Diag(Loc, diag::err_duplicate_member) << II; 4951 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4952 NewFD->setInvalidDecl(); 4953 } 4954 4955 if (getLangOptions().CPlusPlus) { 4956 QualType EltTy = Context.getBaseElementType(T); 4957 4958 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4959 4960 if (!T->isPODType()) 4961 CXXRecord->setPOD(false); 4962 if (!ZeroWidth) 4963 CXXRecord->setEmpty(false); 4964 4965 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4966 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4967 4968 if (!RDecl->hasTrivialConstructor()) 4969 CXXRecord->setHasTrivialConstructor(false); 4970 if (!RDecl->hasTrivialCopyConstructor()) 4971 CXXRecord->setHasTrivialCopyConstructor(false); 4972 if (!RDecl->hasTrivialCopyAssignment()) 4973 CXXRecord->setHasTrivialCopyAssignment(false); 4974 if (!RDecl->hasTrivialDestructor()) 4975 CXXRecord->setHasTrivialDestructor(false); 4976 4977 // C++ 9.5p1: An object of a class with a non-trivial 4978 // constructor, a non-trivial copy constructor, a non-trivial 4979 // destructor, or a non-trivial copy assignment operator 4980 // cannot be a member of a union, nor can an array of such 4981 // objects. 4982 // TODO: C++0x alters this restriction significantly. 4983 if (Record->isUnion()) { 4984 // We check for copy constructors before constructors 4985 // because otherwise we'll never get complaints about 4986 // copy constructors. 4987 4988 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4989 4990 CXXSpecialMember member; 4991 if (!RDecl->hasTrivialCopyConstructor()) 4992 member = CXXCopyConstructor; 4993 else if (!RDecl->hasTrivialConstructor()) 4994 member = CXXDefaultConstructor; 4995 else if (!RDecl->hasTrivialCopyAssignment()) 4996 member = CXXCopyAssignment; 4997 else if (!RDecl->hasTrivialDestructor()) 4998 member = CXXDestructor; 4999 else 5000 member = invalid; 5001 5002 if (member != invalid) { 5003 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5004 DiagnoseNontrivial(RT, member); 5005 NewFD->setInvalidDecl(); 5006 } 5007 } 5008 } 5009 } 5010 5011 // FIXME: We need to pass in the attributes given an AST 5012 // representation, not a parser representation. 5013 if (D) 5014 // FIXME: What to pass instead of TUScope? 5015 ProcessDeclAttributes(TUScope, NewFD, *D); 5016 5017 if (T.isObjCGCWeak()) 5018 Diag(Loc, diag::warn_attribute_weak_on_field); 5019 5020 NewFD->setAccess(AS); 5021 5022 // C++ [dcl.init.aggr]p1: 5023 // An aggregate is an array or a class (clause 9) with [...] no 5024 // private or protected non-static data members (clause 11). 5025 // A POD must be an aggregate. 5026 if (getLangOptions().CPlusPlus && 5027 (AS == AS_private || AS == AS_protected)) { 5028 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5029 CXXRecord->setAggregate(false); 5030 CXXRecord->setPOD(false); 5031 } 5032 5033 return NewFD; 5034} 5035 5036/// DiagnoseNontrivial - Given that a class has a non-trivial 5037/// special member, figure out why. 5038void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5039 QualType QT(T, 0U); 5040 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5041 5042 // Check whether the member was user-declared. 5043 switch (member) { 5044 case CXXDefaultConstructor: 5045 if (RD->hasUserDeclaredConstructor()) { 5046 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5047 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5048 const FunctionDecl *body = 0; 5049 ci->getBody(body); 5050 if (!body || 5051 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5052 SourceLocation CtorLoc = ci->getLocation(); 5053 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5054 return; 5055 } 5056 } 5057 5058 assert(0 && "found no user-declared constructors"); 5059 return; 5060 } 5061 break; 5062 5063 case CXXCopyConstructor: 5064 if (RD->hasUserDeclaredCopyConstructor()) { 5065 SourceLocation CtorLoc = 5066 RD->getCopyConstructor(Context, 0)->getLocation(); 5067 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5068 return; 5069 } 5070 break; 5071 5072 case CXXCopyAssignment: 5073 if (RD->hasUserDeclaredCopyAssignment()) { 5074 // FIXME: this should use the location of the copy 5075 // assignment, not the type. 5076 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5077 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5078 return; 5079 } 5080 break; 5081 5082 case CXXDestructor: 5083 if (RD->hasUserDeclaredDestructor()) { 5084 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5085 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5086 return; 5087 } 5088 break; 5089 } 5090 5091 typedef CXXRecordDecl::base_class_iterator base_iter; 5092 5093 // Virtual bases and members inhibit trivial copying/construction, 5094 // but not trivial destruction. 5095 if (member != CXXDestructor) { 5096 // Check for virtual bases. vbases includes indirect virtual bases, 5097 // so we just iterate through the direct bases. 5098 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5099 if (bi->isVirtual()) { 5100 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5101 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5102 return; 5103 } 5104 5105 // Check for virtual methods. 5106 typedef CXXRecordDecl::method_iterator meth_iter; 5107 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5108 ++mi) { 5109 if (mi->isVirtual()) { 5110 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5111 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5112 return; 5113 } 5114 } 5115 } 5116 5117 bool (CXXRecordDecl::*hasTrivial)() const; 5118 switch (member) { 5119 case CXXDefaultConstructor: 5120 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5121 case CXXCopyConstructor: 5122 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5123 case CXXCopyAssignment: 5124 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5125 case CXXDestructor: 5126 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5127 default: 5128 assert(0 && "unexpected special member"); return; 5129 } 5130 5131 // Check for nontrivial bases (and recurse). 5132 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5133 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5134 assert(BaseRT && "Don't know how to handle dependent bases"); 5135 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5136 if (!(BaseRecTy->*hasTrivial)()) { 5137 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5138 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5139 DiagnoseNontrivial(BaseRT, member); 5140 return; 5141 } 5142 } 5143 5144 // Check for nontrivial members (and recurse). 5145 typedef RecordDecl::field_iterator field_iter; 5146 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5147 ++fi) { 5148 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5149 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5150 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5151 5152 if (!(EltRD->*hasTrivial)()) { 5153 SourceLocation FLoc = (*fi)->getLocation(); 5154 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5155 DiagnoseNontrivial(EltRT, member); 5156 return; 5157 } 5158 } 5159 } 5160 5161 assert(0 && "found no explanation for non-trivial member"); 5162} 5163 5164/// TranslateIvarVisibility - Translate visibility from a token ID to an 5165/// AST enum value. 5166static ObjCIvarDecl::AccessControl 5167TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5168 switch (ivarVisibility) { 5169 default: assert(0 && "Unknown visitibility kind"); 5170 case tok::objc_private: return ObjCIvarDecl::Private; 5171 case tok::objc_public: return ObjCIvarDecl::Public; 5172 case tok::objc_protected: return ObjCIvarDecl::Protected; 5173 case tok::objc_package: return ObjCIvarDecl::Package; 5174 } 5175} 5176 5177/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5178/// in order to create an IvarDecl object for it. 5179Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5180 SourceLocation DeclStart, 5181 DeclPtrTy IntfDecl, 5182 Declarator &D, ExprTy *BitfieldWidth, 5183 tok::ObjCKeywordKind Visibility) { 5184 5185 IdentifierInfo *II = D.getIdentifier(); 5186 Expr *BitWidth = (Expr*)BitfieldWidth; 5187 SourceLocation Loc = DeclStart; 5188 if (II) Loc = D.getIdentifierLoc(); 5189 5190 // FIXME: Unnamed fields can be handled in various different ways, for 5191 // example, unnamed unions inject all members into the struct namespace! 5192 5193 DeclaratorInfo *DInfo = 0; 5194 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5195 5196 if (BitWidth) { 5197 // 6.7.2.1p3, 6.7.2.1p4 5198 if (VerifyBitField(Loc, II, T, BitWidth)) { 5199 D.setInvalidType(); 5200 DeleteExpr(BitWidth); 5201 BitWidth = 0; 5202 } 5203 } else { 5204 // Not a bitfield. 5205 5206 // validate II. 5207 5208 } 5209 5210 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5211 // than a variably modified type. 5212 if (T->isVariablyModifiedType()) { 5213 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5214 D.setInvalidType(); 5215 } 5216 5217 // Get the visibility (access control) for this ivar. 5218 ObjCIvarDecl::AccessControl ac = 5219 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5220 : ObjCIvarDecl::None; 5221 // Must set ivar's DeclContext to its enclosing interface. 5222 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5223 DeclContext *EnclosingContext; 5224 if (ObjCImplementationDecl *IMPDecl = 5225 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5226 // Case of ivar declared in an implementation. Context is that of its class. 5227 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5228 assert(IDecl && "No class- ActOnIvar"); 5229 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5230 } else 5231 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5232 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5233 5234 // Construct the decl. 5235 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5236 EnclosingContext, Loc, II, T, 5237 DInfo, ac, (Expr *)BitfieldWidth); 5238 5239 if (II) { 5240 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5241 LookupResult::ForRedeclaration); 5242 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5243 && !isa<TagDecl>(PrevDecl)) { 5244 Diag(Loc, diag::err_duplicate_member) << II; 5245 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5246 NewID->setInvalidDecl(); 5247 } 5248 } 5249 5250 // Process attributes attached to the ivar. 5251 ProcessDeclAttributes(S, NewID, D); 5252 5253 if (D.isInvalidType()) 5254 NewID->setInvalidDecl(); 5255 5256 if (II) { 5257 // FIXME: When interfaces are DeclContexts, we'll need to add 5258 // these to the interface. 5259 S->AddDecl(DeclPtrTy::make(NewID)); 5260 IdResolver.AddDecl(NewID); 5261 } 5262 5263 return DeclPtrTy::make(NewID); 5264} 5265 5266void Sema::ActOnFields(Scope* S, 5267 SourceLocation RecLoc, DeclPtrTy RecDecl, 5268 DeclPtrTy *Fields, unsigned NumFields, 5269 SourceLocation LBrac, SourceLocation RBrac, 5270 AttributeList *Attr) { 5271 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5272 assert(EnclosingDecl && "missing record or interface decl"); 5273 5274 // If the decl this is being inserted into is invalid, then it may be a 5275 // redeclaration or some other bogus case. Don't try to add fields to it. 5276 if (EnclosingDecl->isInvalidDecl()) { 5277 // FIXME: Deallocate fields? 5278 return; 5279 } 5280 5281 5282 // Verify that all the fields are okay. 5283 unsigned NumNamedMembers = 0; 5284 llvm::SmallVector<FieldDecl*, 32> RecFields; 5285 5286 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5287 for (unsigned i = 0; i != NumFields; ++i) { 5288 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5289 5290 // Get the type for the field. 5291 Type *FDTy = FD->getType().getTypePtr(); 5292 5293 if (!FD->isAnonymousStructOrUnion()) { 5294 // Remember all fields written by the user. 5295 RecFields.push_back(FD); 5296 } 5297 5298 // If the field is already invalid for some reason, don't emit more 5299 // diagnostics about it. 5300 if (FD->isInvalidDecl()) 5301 continue; 5302 5303 // C99 6.7.2.1p2: 5304 // A structure or union shall not contain a member with 5305 // incomplete or function type (hence, a structure shall not 5306 // contain an instance of itself, but may contain a pointer to 5307 // an instance of itself), except that the last member of a 5308 // structure with more than one named member may have incomplete 5309 // array type; such a structure (and any union containing, 5310 // possibly recursively, a member that is such a structure) 5311 // shall not be a member of a structure or an element of an 5312 // array. 5313 if (FDTy->isFunctionType()) { 5314 // Field declared as a function. 5315 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5316 << FD->getDeclName(); 5317 FD->setInvalidDecl(); 5318 EnclosingDecl->setInvalidDecl(); 5319 continue; 5320 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5321 Record && Record->isStruct()) { 5322 // Flexible array member. 5323 if (NumNamedMembers < 1) { 5324 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5325 << FD->getDeclName(); 5326 FD->setInvalidDecl(); 5327 EnclosingDecl->setInvalidDecl(); 5328 continue; 5329 } 5330 // Okay, we have a legal flexible array member at the end of the struct. 5331 if (Record) 5332 Record->setHasFlexibleArrayMember(true); 5333 } else if (!FDTy->isDependentType() && 5334 RequireCompleteType(FD->getLocation(), FD->getType(), 5335 diag::err_field_incomplete)) { 5336 // Incomplete type 5337 FD->setInvalidDecl(); 5338 EnclosingDecl->setInvalidDecl(); 5339 continue; 5340 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5341 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5342 // If this is a member of a union, then entire union becomes "flexible". 5343 if (Record && Record->isUnion()) { 5344 Record->setHasFlexibleArrayMember(true); 5345 } else { 5346 // If this is a struct/class and this is not the last element, reject 5347 // it. Note that GCC supports variable sized arrays in the middle of 5348 // structures. 5349 if (i != NumFields-1) 5350 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5351 << FD->getDeclName() << FD->getType(); 5352 else { 5353 // We support flexible arrays at the end of structs in 5354 // other structs as an extension. 5355 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5356 << FD->getDeclName(); 5357 if (Record) 5358 Record->setHasFlexibleArrayMember(true); 5359 } 5360 } 5361 } 5362 if (Record && FDTTy->getDecl()->hasObjectMember()) 5363 Record->setHasObjectMember(true); 5364 } else if (FDTy->isObjCInterfaceType()) { 5365 /// A field cannot be an Objective-c object 5366 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5367 FD->setInvalidDecl(); 5368 EnclosingDecl->setInvalidDecl(); 5369 continue; 5370 } else if (getLangOptions().ObjC1 && 5371 getLangOptions().getGCMode() != LangOptions::NonGC && 5372 Record && 5373 (FD->getType()->isObjCObjectPointerType() || 5374 FD->getType().isObjCGCStrong())) 5375 Record->setHasObjectMember(true); 5376 // Keep track of the number of named members. 5377 if (FD->getIdentifier()) 5378 ++NumNamedMembers; 5379 } 5380 5381 // Okay, we successfully defined 'Record'. 5382 if (Record) { 5383 Record->completeDefinition(Context); 5384 } else { 5385 ObjCIvarDecl **ClsFields = 5386 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5387 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5388 ID->setIVarList(ClsFields, RecFields.size(), Context); 5389 ID->setLocEnd(RBrac); 5390 // Add ivar's to class's DeclContext. 5391 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5392 ClsFields[i]->setLexicalDeclContext(ID); 5393 ID->addDecl(ClsFields[i]); 5394 } 5395 // Must enforce the rule that ivars in the base classes may not be 5396 // duplicates. 5397 if (ID->getSuperClass()) { 5398 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5399 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5400 ObjCIvarDecl* Ivar = (*IVI); 5401 5402 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5403 ObjCIvarDecl* prevIvar = 5404 ID->getSuperClass()->lookupInstanceVariable(II); 5405 if (prevIvar) { 5406 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5407 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5408 } 5409 } 5410 } 5411 } 5412 } else if (ObjCImplementationDecl *IMPDecl = 5413 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5414 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5415 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5416 // Ivar declared in @implementation never belongs to the implementation. 5417 // Only it is in implementation's lexical context. 5418 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5419 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5420 } 5421 } 5422 5423 if (Attr) 5424 ProcessDeclAttributeList(S, Record, Attr); 5425} 5426 5427EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5428 EnumConstantDecl *LastEnumConst, 5429 SourceLocation IdLoc, 5430 IdentifierInfo *Id, 5431 ExprArg val) { 5432 Expr *Val = (Expr *)val.get(); 5433 5434 llvm::APSInt EnumVal(32); 5435 QualType EltTy; 5436 if (Val) { 5437 if (Val->isTypeDependent()) 5438 EltTy = Context.DependentTy; 5439 else { 5440 // Make sure to promote the operand type to int. 5441 UsualUnaryConversions(Val); 5442 if (Val != val.get()) { 5443 val.release(); 5444 val = Val; 5445 } 5446 5447 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5448 SourceLocation ExpLoc; 5449 if (!Val->isValueDependent() && 5450 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5451 Val = 0; 5452 } else { 5453 EltTy = Val->getType(); 5454 } 5455 } 5456 } 5457 5458 if (!Val) { 5459 if (LastEnumConst) { 5460 // Assign the last value + 1. 5461 EnumVal = LastEnumConst->getInitVal(); 5462 ++EnumVal; 5463 5464 // Check for overflow on increment. 5465 if (EnumVal < LastEnumConst->getInitVal()) 5466 Diag(IdLoc, diag::warn_enum_value_overflow); 5467 5468 EltTy = LastEnumConst->getType(); 5469 } else { 5470 // First value, set to zero. 5471 EltTy = Context.IntTy; 5472 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5473 } 5474 } 5475 5476 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5477 5478 val.release(); 5479 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5480 Val, EnumVal); 5481} 5482 5483 5484Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5485 DeclPtrTy lastEnumConst, 5486 SourceLocation IdLoc, 5487 IdentifierInfo *Id, 5488 SourceLocation EqualLoc, ExprTy *val) { 5489 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5490 EnumConstantDecl *LastEnumConst = 5491 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5492 Expr *Val = static_cast<Expr*>(val); 5493 5494 // The scope passed in may not be a decl scope. Zip up the scope tree until 5495 // we find one that is. 5496 S = getNonFieldDeclScope(S); 5497 5498 // Verify that there isn't already something declared with this name in this 5499 // scope. 5500 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5501 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5502 // Maybe we will complain about the shadowed template parameter. 5503 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5504 // Just pretend that we didn't see the previous declaration. 5505 PrevDecl = 0; 5506 } 5507 5508 if (PrevDecl) { 5509 // When in C++, we may get a TagDecl with the same name; in this case the 5510 // enum constant will 'hide' the tag. 5511 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5512 "Received TagDecl when not in C++!"); 5513 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5514 if (isa<EnumConstantDecl>(PrevDecl)) 5515 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5516 else 5517 Diag(IdLoc, diag::err_redefinition) << Id; 5518 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5519 if (Val) Val->Destroy(Context); 5520 return DeclPtrTy(); 5521 } 5522 } 5523 5524 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5525 IdLoc, Id, Owned(Val)); 5526 5527 // Register this decl in the current scope stack. 5528 if (New) 5529 PushOnScopeChains(New, S); 5530 5531 return DeclPtrTy::make(New); 5532} 5533 5534void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5535 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5536 DeclPtrTy *Elements, unsigned NumElements, 5537 Scope *S, AttributeList *Attr) { 5538 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5539 QualType EnumType = Context.getTypeDeclType(Enum); 5540 5541 if (Attr) 5542 ProcessDeclAttributeList(S, Enum, Attr); 5543 5544 // TODO: If the result value doesn't fit in an int, it must be a long or long 5545 // long value. ISO C does not support this, but GCC does as an extension, 5546 // emit a warning. 5547 unsigned IntWidth = Context.Target.getIntWidth(); 5548 unsigned CharWidth = Context.Target.getCharWidth(); 5549 unsigned ShortWidth = Context.Target.getShortWidth(); 5550 5551 // Verify that all the values are okay, compute the size of the values, and 5552 // reverse the list. 5553 unsigned NumNegativeBits = 0; 5554 unsigned NumPositiveBits = 0; 5555 5556 // Keep track of whether all elements have type int. 5557 bool AllElementsInt = true; 5558 5559 for (unsigned i = 0; i != NumElements; ++i) { 5560 EnumConstantDecl *ECD = 5561 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5562 if (!ECD) continue; // Already issued a diagnostic. 5563 5564 // If the enum value doesn't fit in an int, emit an extension warning. 5565 const llvm::APSInt &InitVal = ECD->getInitVal(); 5566 assert(InitVal.getBitWidth() >= IntWidth && 5567 "Should have promoted value to int"); 5568 if (InitVal.getBitWidth() > IntWidth) { 5569 llvm::APSInt V(InitVal); 5570 V.trunc(IntWidth); 5571 V.extend(InitVal.getBitWidth()); 5572 if (V != InitVal) 5573 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5574 << InitVal.toString(10); 5575 } 5576 5577 // Keep track of the size of positive and negative values. 5578 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5579 NumPositiveBits = std::max(NumPositiveBits, 5580 (unsigned)InitVal.getActiveBits()); 5581 else 5582 NumNegativeBits = std::max(NumNegativeBits, 5583 (unsigned)InitVal.getMinSignedBits()); 5584 5585 // Keep track of whether every enum element has type int (very commmon). 5586 if (AllElementsInt) 5587 AllElementsInt = ECD->getType() == Context.IntTy; 5588 } 5589 5590 // Figure out the type that should be used for this enum. 5591 // FIXME: Support -fshort-enums. 5592 QualType BestType; 5593 unsigned BestWidth; 5594 5595 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5596 5597 if (NumNegativeBits) { 5598 // If there is a negative value, figure out the smallest integer type (of 5599 // int/long/longlong) that fits. 5600 // If it's packed, check also if it fits a char or a short. 5601 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5602 BestType = Context.SignedCharTy; 5603 BestWidth = CharWidth; 5604 } else if (Packed && NumNegativeBits <= ShortWidth && 5605 NumPositiveBits < ShortWidth) { 5606 BestType = Context.ShortTy; 5607 BestWidth = ShortWidth; 5608 } 5609 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5610 BestType = Context.IntTy; 5611 BestWidth = IntWidth; 5612 } else { 5613 BestWidth = Context.Target.getLongWidth(); 5614 5615 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5616 BestType = Context.LongTy; 5617 else { 5618 BestWidth = Context.Target.getLongLongWidth(); 5619 5620 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5621 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5622 BestType = Context.LongLongTy; 5623 } 5624 } 5625 } else { 5626 // If there is no negative value, figure out which of uint, ulong, ulonglong 5627 // fits. 5628 // If it's packed, check also if it fits a char or a short. 5629 if (Packed && NumPositiveBits <= CharWidth) { 5630 BestType = Context.UnsignedCharTy; 5631 BestWidth = CharWidth; 5632 } else if (Packed && NumPositiveBits <= ShortWidth) { 5633 BestType = Context.UnsignedShortTy; 5634 BestWidth = ShortWidth; 5635 } 5636 else if (NumPositiveBits <= IntWidth) { 5637 BestType = Context.UnsignedIntTy; 5638 BestWidth = IntWidth; 5639 } else if (NumPositiveBits <= 5640 (BestWidth = Context.Target.getLongWidth())) { 5641 BestType = Context.UnsignedLongTy; 5642 } else { 5643 BestWidth = Context.Target.getLongLongWidth(); 5644 assert(NumPositiveBits <= BestWidth && 5645 "How could an initializer get larger than ULL?"); 5646 BestType = Context.UnsignedLongLongTy; 5647 } 5648 } 5649 5650 // Loop over all of the enumerator constants, changing their types to match 5651 // the type of the enum if needed. 5652 for (unsigned i = 0; i != NumElements; ++i) { 5653 EnumConstantDecl *ECD = 5654 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5655 if (!ECD) continue; // Already issued a diagnostic. 5656 5657 // Standard C says the enumerators have int type, but we allow, as an 5658 // extension, the enumerators to be larger than int size. If each 5659 // enumerator value fits in an int, type it as an int, otherwise type it the 5660 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5661 // that X has type 'int', not 'unsigned'. 5662 if (ECD->getType() == Context.IntTy) { 5663 // Make sure the init value is signed. 5664 llvm::APSInt IV = ECD->getInitVal(); 5665 IV.setIsSigned(true); 5666 ECD->setInitVal(IV); 5667 5668 if (getLangOptions().CPlusPlus) 5669 // C++ [dcl.enum]p4: Following the closing brace of an 5670 // enum-specifier, each enumerator has the type of its 5671 // enumeration. 5672 ECD->setType(EnumType); 5673 continue; // Already int type. 5674 } 5675 5676 // Determine whether the value fits into an int. 5677 llvm::APSInt InitVal = ECD->getInitVal(); 5678 bool FitsInInt; 5679 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5680 FitsInInt = InitVal.getActiveBits() < IntWidth; 5681 else 5682 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5683 5684 // If it fits into an integer type, force it. Otherwise force it to match 5685 // the enum decl type. 5686 QualType NewTy; 5687 unsigned NewWidth; 5688 bool NewSign; 5689 if (FitsInInt) { 5690 NewTy = Context.IntTy; 5691 NewWidth = IntWidth; 5692 NewSign = true; 5693 } else if (ECD->getType() == BestType) { 5694 // Already the right type! 5695 if (getLangOptions().CPlusPlus) 5696 // C++ [dcl.enum]p4: Following the closing brace of an 5697 // enum-specifier, each enumerator has the type of its 5698 // enumeration. 5699 ECD->setType(EnumType); 5700 continue; 5701 } else { 5702 NewTy = BestType; 5703 NewWidth = BestWidth; 5704 NewSign = BestType->isSignedIntegerType(); 5705 } 5706 5707 // Adjust the APSInt value. 5708 InitVal.extOrTrunc(NewWidth); 5709 InitVal.setIsSigned(NewSign); 5710 ECD->setInitVal(InitVal); 5711 5712 // Adjust the Expr initializer and type. 5713 if (ECD->getInitExpr()) 5714 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5715 CastExpr::CK_IntegralCast, 5716 ECD->getInitExpr(), 5717 /*isLvalue=*/false)); 5718 if (getLangOptions().CPlusPlus) 5719 // C++ [dcl.enum]p4: Following the closing brace of an 5720 // enum-specifier, each enumerator has the type of its 5721 // enumeration. 5722 ECD->setType(EnumType); 5723 else 5724 ECD->setType(NewTy); 5725 } 5726 5727 Enum->completeDefinition(Context, BestType); 5728} 5729 5730Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5731 ExprArg expr) { 5732 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5733 5734 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5735 Loc, AsmString); 5736 CurContext->addDecl(New); 5737 return DeclPtrTy::make(New); 5738} 5739 5740void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5741 SourceLocation PragmaLoc, 5742 SourceLocation NameLoc) { 5743 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5744 5745 if (PrevDecl) { 5746 PrevDecl->addAttr(::new (Context) WeakAttr()); 5747 } else { 5748 (void)WeakUndeclaredIdentifiers.insert( 5749 std::pair<IdentifierInfo*,WeakInfo> 5750 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5751 } 5752} 5753 5754void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5755 IdentifierInfo* AliasName, 5756 SourceLocation PragmaLoc, 5757 SourceLocation NameLoc, 5758 SourceLocation AliasNameLoc) { 5759 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5760 WeakInfo W = WeakInfo(Name, NameLoc); 5761 5762 if (PrevDecl) { 5763 if (!PrevDecl->hasAttr<AliasAttr>()) 5764 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5765 DeclApplyPragmaWeak(TUScope, ND, W); 5766 } else { 5767 (void)WeakUndeclaredIdentifiers.insert( 5768 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5769 } 5770} 5771