SemaDecl.cpp revision 02a24ee67c0a91bdb0db8a651d5748595652e670
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/Analysis/CFG.h" 19#include "clang/AST/CXXInheritance.h" 20#include "clang/AST/DeclObjC.h" 21#include "clang/AST/DeclTemplate.h" 22#include "clang/AST/ExprCXX.h" 23#include "clang/AST/StmtCXX.h" 24#include "clang/AST/StmtObjC.h" 25#include "clang/Parse/DeclSpec.h" 26#include "clang/Parse/ParseDiagnostic.h" 27#include "clang/Basic/PartialDiagnostic.h" 28#include "clang/Basic/SourceManager.h" 29#include "clang/Basic/TargetInfo.h" 30// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 31#include "clang/Lex/Preprocessor.h" 32#include "clang/Lex/HeaderSearch.h" 33#include "llvm/ADT/BitVector.h" 34#include "llvm/ADT/STLExtras.h" 35#include <algorithm> 36#include <cstring> 37#include <functional> 38#include <queue> 39using namespace clang; 40 41/// getDeclName - Return a pretty name for the specified decl if possible, or 42/// an empty string if not. This is used for pretty crash reporting. 43std::string Sema::getDeclName(DeclPtrTy d) { 44 Decl *D = d.getAs<Decl>(); 45 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 46 return DN->getQualifiedNameAsString(); 47 return ""; 48} 49 50Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 51 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 52} 53 54/// \brief If the identifier refers to a type name within this scope, 55/// return the declaration of that type. 56/// 57/// This routine performs ordinary name lookup of the identifier II 58/// within the given scope, with optional C++ scope specifier SS, to 59/// determine whether the name refers to a type. If so, returns an 60/// opaque pointer (actually a QualType) corresponding to that 61/// type. Otherwise, returns NULL. 62/// 63/// If name lookup results in an ambiguity, this routine will complain 64/// and then return NULL. 65Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 66 Scope *S, const CXXScopeSpec *SS, 67 bool isClassName) { 68 // C++ [temp.res]p3: 69 // A qualified-id that refers to a type and in which the 70 // nested-name-specifier depends on a template-parameter (14.6.2) 71 // shall be prefixed by the keyword typename to indicate that the 72 // qualified-id denotes a type, forming an 73 // elaborated-type-specifier (7.1.5.3). 74 // 75 // We therefore do not perform any name lookup if the result would 76 // refer to a member of an unknown specialization. 77 if (SS && isUnknownSpecialization(*SS)) { 78 if (!isClassName) 79 return 0; 80 81 // We know from the grammar that this name refers to a type, so build a 82 // TypenameType node to describe the type. 83 // FIXME: Record somewhere that this TypenameType node has no "typename" 84 // keyword associated with it. 85 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 86 II, SS->getRange()).getAsOpaquePtr(); 87 } 88 89 LookupResult Result; 90 LookupParsedName(Result, S, SS, &II, LookupOrdinaryName, false, false); 91 92 NamedDecl *IIDecl = 0; 93 switch (Result.getKind()) { 94 case LookupResult::NotFound: 95 case LookupResult::FoundOverloaded: 96 return 0; 97 98 case LookupResult::Ambiguous: 99 // Recover from type-hiding ambiguities by hiding the type. We'll 100 // do the lookup again when looking for an object, and we can 101 // diagnose the error then. If we don't do this, then the error 102 // about hiding the type will be immediately followed by an error 103 // that only makes sense if the identifier was treated like a type. 104 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) 105 return 0; 106 107 // Look to see if we have a type anywhere in the list of results. 108 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 109 Res != ResEnd; ++Res) { 110 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 111 if (!IIDecl || 112 (*Res)->getLocation().getRawEncoding() < 113 IIDecl->getLocation().getRawEncoding()) 114 IIDecl = *Res; 115 } 116 } 117 118 if (!IIDecl) { 119 // None of the entities we found is a type, so there is no way 120 // to even assume that the result is a type. In this case, don't 121 // complain about the ambiguity. The parser will either try to 122 // perform this lookup again (e.g., as an object name), which 123 // will produce the ambiguity, or will complain that it expected 124 // a type name. 125 return 0; 126 } 127 128 // We found a type within the ambiguous lookup; diagnose the 129 // ambiguity and then return that type. This might be the right 130 // answer, or it might not be, but it suppresses any attempt to 131 // perform the name lookup again. 132 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 133 break; 134 135 case LookupResult::Found: 136 IIDecl = Result.getFoundDecl(); 137 break; 138 } 139 140 assert(IIDecl && "Didn't find decl"); 141 142 QualType T; 143 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 144 // C++ [temp.local]p2: 145 // Within the scope of a class template specialization or 146 // partial specialization, when the injected-class-name is 147 // not followed by a <, it is equivalent to the 148 // injected-class-name followed by the template-argument s 149 // of the class template specialization or partial 150 // specialization enclosed in <>. 151 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 152 if (RD->isInjectedClassName()) 153 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 154 T = Template->getInjectedClassNameType(Context); 155 156 if (T.isNull()) 157 T = Context.getTypeDeclType(TD); 158 159 if (SS) 160 T = getQualifiedNameType(*SS, T); 161 162 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 163 T = Context.getObjCInterfaceType(IDecl); 164 } else 165 return 0; 166 167 return T.getAsOpaquePtr(); 168} 169 170/// isTagName() - This method is called *for error recovery purposes only* 171/// to determine if the specified name is a valid tag name ("struct foo"). If 172/// so, this returns the TST for the tag corresponding to it (TST_enum, 173/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 174/// where the user forgot to specify the tag. 175DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 176 // Do a tag name lookup in this scope. 177 LookupResult R; 178 LookupName(R, S, &II, LookupTagName, false, false); 179 if (R.getKind() == LookupResult::Found) 180 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 181 switch (TD->getTagKind()) { 182 case TagDecl::TK_struct: return DeclSpec::TST_struct; 183 case TagDecl::TK_union: return DeclSpec::TST_union; 184 case TagDecl::TK_class: return DeclSpec::TST_class; 185 case TagDecl::TK_enum: return DeclSpec::TST_enum; 186 } 187 } 188 189 return DeclSpec::TST_unspecified; 190} 191 192bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 193 SourceLocation IILoc, 194 Scope *S, 195 const CXXScopeSpec *SS, 196 TypeTy *&SuggestedType) { 197 // We don't have anything to suggest (yet). 198 SuggestedType = 0; 199 200 // FIXME: Should we move the logic that tries to recover from a missing tag 201 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 202 203 if (!SS) 204 Diag(IILoc, diag::err_unknown_typename) << &II; 205 else if (DeclContext *DC = computeDeclContext(*SS, false)) 206 Diag(IILoc, diag::err_typename_nested_not_found) 207 << &II << DC << SS->getRange(); 208 else if (isDependentScopeSpecifier(*SS)) { 209 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 210 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 211 << SourceRange(SS->getRange().getBegin(), IILoc) 212 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 213 "typename "); 214 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 215 } else { 216 assert(SS && SS->isInvalid() && 217 "Invalid scope specifier has already been diagnosed"); 218 } 219 220 return true; 221} 222 223// Determines the context to return to after temporarily entering a 224// context. This depends in an unnecessarily complicated way on the 225// exact ordering of callbacks from the parser. 226DeclContext *Sema::getContainingDC(DeclContext *DC) { 227 228 // Functions defined inline within classes aren't parsed until we've 229 // finished parsing the top-level class, so the top-level class is 230 // the context we'll need to return to. 231 if (isa<FunctionDecl>(DC)) { 232 DC = DC->getLexicalParent(); 233 234 // A function not defined within a class will always return to its 235 // lexical context. 236 if (!isa<CXXRecordDecl>(DC)) 237 return DC; 238 239 // A C++ inline method/friend is parsed *after* the topmost class 240 // it was declared in is fully parsed ("complete"); the topmost 241 // class is the context we need to return to. 242 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 243 DC = RD; 244 245 // Return the declaration context of the topmost class the inline method is 246 // declared in. 247 return DC; 248 } 249 250 if (isa<ObjCMethodDecl>(DC)) 251 return Context.getTranslationUnitDecl(); 252 253 return DC->getLexicalParent(); 254} 255 256void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 257 assert(getContainingDC(DC) == CurContext && 258 "The next DeclContext should be lexically contained in the current one."); 259 CurContext = DC; 260 S->setEntity(DC); 261} 262 263void Sema::PopDeclContext() { 264 assert(CurContext && "DeclContext imbalance!"); 265 266 CurContext = getContainingDC(CurContext); 267} 268 269/// EnterDeclaratorContext - Used when we must lookup names in the context 270/// of a declarator's nested name specifier. 271void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 272 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 273 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 274 CurContext = DC; 275 assert(CurContext && "No context?"); 276 S->setEntity(CurContext); 277} 278 279void Sema::ExitDeclaratorContext(Scope *S) { 280 S->setEntity(PreDeclaratorDC); 281 PreDeclaratorDC = 0; 282 283 // Reset CurContext to the nearest enclosing context. 284 while (!S->getEntity() && S->getParent()) 285 S = S->getParent(); 286 CurContext = static_cast<DeclContext*>(S->getEntity()); 287 assert(CurContext && "No context?"); 288} 289 290/// \brief Determine whether we allow overloading of the function 291/// PrevDecl with another declaration. 292/// 293/// This routine determines whether overloading is possible, not 294/// whether some new function is actually an overload. It will return 295/// true in C++ (where we can always provide overloads) or, as an 296/// extension, in C when the previous function is already an 297/// overloaded function declaration or has the "overloadable" 298/// attribute. 299static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 300 if (Context.getLangOptions().CPlusPlus) 301 return true; 302 303 if (isa<OverloadedFunctionDecl>(PrevDecl)) 304 return true; 305 306 return PrevDecl->getAttr<OverloadableAttr>() != 0; 307} 308 309/// Add this decl to the scope shadowed decl chains. 310void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 311 // Move up the scope chain until we find the nearest enclosing 312 // non-transparent context. The declaration will be introduced into this 313 // scope. 314 while (S->getEntity() && 315 ((DeclContext *)S->getEntity())->isTransparentContext()) 316 S = S->getParent(); 317 318 // Add scoped declarations into their context, so that they can be 319 // found later. Declarations without a context won't be inserted 320 // into any context. 321 if (AddToContext) 322 CurContext->addDecl(D); 323 324 // Out-of-line function and variable definitions should not be pushed into 325 // scope. 326 if ((isa<FunctionTemplateDecl>(D) && 327 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 328 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 329 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 330 return; 331 332 // If this replaces anything in the current scope, 333 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 334 IEnd = IdResolver.end(); 335 for (; I != IEnd; ++I) { 336 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 337 S->RemoveDecl(DeclPtrTy::make(*I)); 338 IdResolver.RemoveDecl(*I); 339 340 // Should only need to replace one decl. 341 break; 342 } 343 } 344 345 S->AddDecl(DeclPtrTy::make(D)); 346 IdResolver.AddDecl(D); 347} 348 349bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 350 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 351 // Look inside the overload set to determine if any of the declarations 352 // are in scope. (Possibly) build a new overload set containing only 353 // those declarations that are in scope. 354 OverloadedFunctionDecl *NewOvl = 0; 355 bool FoundInScope = false; 356 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 357 FEnd = Ovl->function_end(); 358 F != FEnd; ++F) { 359 NamedDecl *FD = F->get(); 360 if (!isDeclInScope(FD, Ctx, S)) { 361 if (!NewOvl && F != Ovl->function_begin()) { 362 NewOvl = OverloadedFunctionDecl::Create(Context, 363 F->get()->getDeclContext(), 364 F->get()->getDeclName()); 365 D = NewOvl; 366 for (OverloadedFunctionDecl::function_iterator 367 First = Ovl->function_begin(); 368 First != F; ++First) 369 NewOvl->addOverload(*First); 370 } 371 } else { 372 FoundInScope = true; 373 if (NewOvl) 374 NewOvl->addOverload(*F); 375 } 376 } 377 378 return FoundInScope; 379 } 380 381 return IdResolver.isDeclInScope(D, Ctx, Context, S); 382} 383 384void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 385 if (S->decl_empty()) return; 386 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 387 "Scope shouldn't contain decls!"); 388 389 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 390 I != E; ++I) { 391 Decl *TmpD = (*I).getAs<Decl>(); 392 assert(TmpD && "This decl didn't get pushed??"); 393 394 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 395 NamedDecl *D = cast<NamedDecl>(TmpD); 396 397 if (!D->getDeclName()) continue; 398 399 // Diagnose unused variables in this scope. 400 if (!D->isUsed() && !D->hasAttr<UnusedAttr>() && isa<VarDecl>(D) && 401 !isa<ParmVarDecl>(D) && !isa<ImplicitParamDecl>(D) && 402 D->getDeclContext()->isFunctionOrMethod()) 403 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 404 405 // Remove this name from our lexical scope. 406 IdResolver.RemoveDecl(D); 407 } 408} 409 410/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 411/// return 0 if one not found. 412ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 413 // The third "scope" argument is 0 since we aren't enabling lazy built-in 414 // creation from this context. 415 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 416 417 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 418} 419 420/// getNonFieldDeclScope - Retrieves the innermost scope, starting 421/// from S, where a non-field would be declared. This routine copes 422/// with the difference between C and C++ scoping rules in structs and 423/// unions. For example, the following code is well-formed in C but 424/// ill-formed in C++: 425/// @code 426/// struct S6 { 427/// enum { BAR } e; 428/// }; 429/// 430/// void test_S6() { 431/// struct S6 a; 432/// a.e = BAR; 433/// } 434/// @endcode 435/// For the declaration of BAR, this routine will return a different 436/// scope. The scope S will be the scope of the unnamed enumeration 437/// within S6. In C++, this routine will return the scope associated 438/// with S6, because the enumeration's scope is a transparent 439/// context but structures can contain non-field names. In C, this 440/// routine will return the translation unit scope, since the 441/// enumeration's scope is a transparent context and structures cannot 442/// contain non-field names. 443Scope *Sema::getNonFieldDeclScope(Scope *S) { 444 while (((S->getFlags() & Scope::DeclScope) == 0) || 445 (S->getEntity() && 446 ((DeclContext *)S->getEntity())->isTransparentContext()) || 447 (S->isClassScope() && !getLangOptions().CPlusPlus)) 448 S = S->getParent(); 449 return S; 450} 451 452void Sema::InitBuiltinVaListType() { 453 if (!Context.getBuiltinVaListType().isNull()) 454 return; 455 456 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 457 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 458 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 459 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 460} 461 462/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 463/// file scope. lazily create a decl for it. ForRedeclaration is true 464/// if we're creating this built-in in anticipation of redeclaring the 465/// built-in. 466NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 467 Scope *S, bool ForRedeclaration, 468 SourceLocation Loc) { 469 Builtin::ID BID = (Builtin::ID)bid; 470 471 if (Context.BuiltinInfo.hasVAListUse(BID)) 472 InitBuiltinVaListType(); 473 474 ASTContext::GetBuiltinTypeError Error; 475 QualType R = Context.GetBuiltinType(BID, Error); 476 switch (Error) { 477 case ASTContext::GE_None: 478 // Okay 479 break; 480 481 case ASTContext::GE_Missing_stdio: 482 if (ForRedeclaration) 483 Diag(Loc, diag::err_implicit_decl_requires_stdio) 484 << Context.BuiltinInfo.GetName(BID); 485 return 0; 486 487 case ASTContext::GE_Missing_setjmp: 488 if (ForRedeclaration) 489 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 490 << Context.BuiltinInfo.GetName(BID); 491 return 0; 492 } 493 494 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 495 Diag(Loc, diag::ext_implicit_lib_function_decl) 496 << Context.BuiltinInfo.GetName(BID) 497 << R; 498 if (Context.BuiltinInfo.getHeaderName(BID) && 499 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 500 != Diagnostic::Ignored) 501 Diag(Loc, diag::note_please_include_header) 502 << Context.BuiltinInfo.getHeaderName(BID) 503 << Context.BuiltinInfo.GetName(BID); 504 } 505 506 FunctionDecl *New = FunctionDecl::Create(Context, 507 Context.getTranslationUnitDecl(), 508 Loc, II, R, /*DInfo=*/0, 509 FunctionDecl::Extern, false, 510 /*hasPrototype=*/true); 511 New->setImplicit(); 512 513 // Create Decl objects for each parameter, adding them to the 514 // FunctionDecl. 515 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 516 llvm::SmallVector<ParmVarDecl*, 16> Params; 517 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 518 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 519 FT->getArgType(i), /*DInfo=*/0, 520 VarDecl::None, 0)); 521 New->setParams(Context, Params.data(), Params.size()); 522 } 523 524 AddKnownFunctionAttributes(New); 525 526 // TUScope is the translation-unit scope to insert this function into. 527 // FIXME: This is hideous. We need to teach PushOnScopeChains to 528 // relate Scopes to DeclContexts, and probably eliminate CurContext 529 // entirely, but we're not there yet. 530 DeclContext *SavedContext = CurContext; 531 CurContext = Context.getTranslationUnitDecl(); 532 PushOnScopeChains(New, TUScope); 533 CurContext = SavedContext; 534 return New; 535} 536 537/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 538/// same name and scope as a previous declaration 'Old'. Figure out 539/// how to resolve this situation, merging decls or emitting 540/// diagnostics as appropriate. If there was an error, set New to be invalid. 541/// 542void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 543 // If either decl is known invalid already, set the new one to be invalid and 544 // don't bother doing any merging checks. 545 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 546 return New->setInvalidDecl(); 547 548 // Allow multiple definitions for ObjC built-in typedefs. 549 // FIXME: Verify the underlying types are equivalent! 550 if (getLangOptions().ObjC1) { 551 const IdentifierInfo *TypeID = New->getIdentifier(); 552 switch (TypeID->getLength()) { 553 default: break; 554 case 2: 555 if (!TypeID->isStr("id")) 556 break; 557 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 558 // Install the built-in type for 'id', ignoring the current definition. 559 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 560 return; 561 case 5: 562 if (!TypeID->isStr("Class")) 563 break; 564 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 565 // Install the built-in type for 'Class', ignoring the current definition. 566 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 567 return; 568 case 3: 569 if (!TypeID->isStr("SEL")) 570 break; 571 Context.setObjCSelType(Context.getTypeDeclType(New)); 572 return; 573 case 8: 574 if (!TypeID->isStr("Protocol")) 575 break; 576 Context.setObjCProtoType(New->getUnderlyingType()); 577 return; 578 } 579 // Fall through - the typedef name was not a builtin type. 580 } 581 // Verify the old decl was also a type. 582 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 583 if (!Old) { 584 Diag(New->getLocation(), diag::err_redefinition_different_kind) 585 << New->getDeclName(); 586 if (OldD->getLocation().isValid()) 587 Diag(OldD->getLocation(), diag::note_previous_definition); 588 return New->setInvalidDecl(); 589 } 590 591 // Determine the "old" type we'll use for checking and diagnostics. 592 QualType OldType; 593 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 594 OldType = OldTypedef->getUnderlyingType(); 595 else 596 OldType = Context.getTypeDeclType(Old); 597 598 // If the typedef types are not identical, reject them in all languages and 599 // with any extensions enabled. 600 601 if (OldType != New->getUnderlyingType() && 602 Context.getCanonicalType(OldType) != 603 Context.getCanonicalType(New->getUnderlyingType())) { 604 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 605 << New->getUnderlyingType() << OldType; 606 if (Old->getLocation().isValid()) 607 Diag(Old->getLocation(), diag::note_previous_definition); 608 return New->setInvalidDecl(); 609 } 610 611 if (getLangOptions().Microsoft) 612 return; 613 614 // C++ [dcl.typedef]p2: 615 // In a given non-class scope, a typedef specifier can be used to 616 // redefine the name of any type declared in that scope to refer 617 // to the type to which it already refers. 618 if (getLangOptions().CPlusPlus) { 619 if (!isa<CXXRecordDecl>(CurContext)) 620 return; 621 Diag(New->getLocation(), diag::err_redefinition) 622 << New->getDeclName(); 623 Diag(Old->getLocation(), diag::note_previous_definition); 624 return New->setInvalidDecl(); 625 } 626 627 // If we have a redefinition of a typedef in C, emit a warning. This warning 628 // is normally mapped to an error, but can be controlled with 629 // -Wtypedef-redefinition. If either the original or the redefinition is 630 // in a system header, don't emit this for compatibility with GCC. 631 if (PP.getDiagnostics().getSuppressSystemWarnings() && 632 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 633 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 634 return; 635 636 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 637 << New->getDeclName(); 638 Diag(Old->getLocation(), diag::note_previous_definition); 639 return; 640} 641 642/// DeclhasAttr - returns true if decl Declaration already has the target 643/// attribute. 644static bool 645DeclHasAttr(const Decl *decl, const Attr *target) { 646 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 647 if (attr->getKind() == target->getKind()) 648 return true; 649 650 return false; 651} 652 653/// MergeAttributes - append attributes from the Old decl to the New one. 654static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 655 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 656 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 657 Attr *NewAttr = attr->clone(C); 658 NewAttr->setInherited(true); 659 New->addAttr(NewAttr); 660 } 661 } 662} 663 664/// Used in MergeFunctionDecl to keep track of function parameters in 665/// C. 666struct GNUCompatibleParamWarning { 667 ParmVarDecl *OldParm; 668 ParmVarDecl *NewParm; 669 QualType PromotedType; 670}; 671 672/// MergeFunctionDecl - We just parsed a function 'New' from 673/// declarator D which has the same name and scope as a previous 674/// declaration 'Old'. Figure out how to resolve this situation, 675/// merging decls or emitting diagnostics as appropriate. 676/// 677/// In C++, New and Old must be declarations that are not 678/// overloaded. Use IsOverload to determine whether New and Old are 679/// overloaded, and to select the Old declaration that New should be 680/// merged with. 681/// 682/// Returns true if there was an error, false otherwise. 683bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 684 assert(!isa<OverloadedFunctionDecl>(OldD) && 685 "Cannot merge with an overloaded function declaration"); 686 687 // Verify the old decl was also a function. 688 FunctionDecl *Old = 0; 689 if (FunctionTemplateDecl *OldFunctionTemplate 690 = dyn_cast<FunctionTemplateDecl>(OldD)) 691 Old = OldFunctionTemplate->getTemplatedDecl(); 692 else 693 Old = dyn_cast<FunctionDecl>(OldD); 694 if (!Old) { 695 Diag(New->getLocation(), diag::err_redefinition_different_kind) 696 << New->getDeclName(); 697 Diag(OldD->getLocation(), diag::note_previous_definition); 698 return true; 699 } 700 701 // Determine whether the previous declaration was a definition, 702 // implicit declaration, or a declaration. 703 diag::kind PrevDiag; 704 if (Old->isThisDeclarationADefinition()) 705 PrevDiag = diag::note_previous_definition; 706 else if (Old->isImplicit()) 707 PrevDiag = diag::note_previous_implicit_declaration; 708 else 709 PrevDiag = diag::note_previous_declaration; 710 711 QualType OldQType = Context.getCanonicalType(Old->getType()); 712 QualType NewQType = Context.getCanonicalType(New->getType()); 713 714 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 715 New->getStorageClass() == FunctionDecl::Static && 716 Old->getStorageClass() != FunctionDecl::Static) { 717 Diag(New->getLocation(), diag::err_static_non_static) 718 << New; 719 Diag(Old->getLocation(), PrevDiag); 720 return true; 721 } 722 723 if (getLangOptions().CPlusPlus) { 724 // (C++98 13.1p2): 725 // Certain function declarations cannot be overloaded: 726 // -- Function declarations that differ only in the return type 727 // cannot be overloaded. 728 QualType OldReturnType 729 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 730 QualType NewReturnType 731 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 732 if (OldReturnType != NewReturnType) { 733 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 734 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 735 return true; 736 } 737 738 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 739 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 740 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 741 NewMethod->getLexicalDeclContext()->isRecord()) { 742 // -- Member function declarations with the same name and the 743 // same parameter types cannot be overloaded if any of them 744 // is a static member function declaration. 745 if (OldMethod->isStatic() || NewMethod->isStatic()) { 746 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 747 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 748 return true; 749 } 750 751 // C++ [class.mem]p1: 752 // [...] A member shall not be declared twice in the 753 // member-specification, except that a nested class or member 754 // class template can be declared and then later defined. 755 unsigned NewDiag; 756 if (isa<CXXConstructorDecl>(OldMethod)) 757 NewDiag = diag::err_constructor_redeclared; 758 else if (isa<CXXDestructorDecl>(NewMethod)) 759 NewDiag = diag::err_destructor_redeclared; 760 else if (isa<CXXConversionDecl>(NewMethod)) 761 NewDiag = diag::err_conv_function_redeclared; 762 else 763 NewDiag = diag::err_member_redeclared; 764 765 Diag(New->getLocation(), NewDiag); 766 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 767 } 768 769 // (C++98 8.3.5p3): 770 // All declarations for a function shall agree exactly in both the 771 // return type and the parameter-type-list. 772 if (OldQType == NewQType) 773 return MergeCompatibleFunctionDecls(New, Old); 774 775 // Fall through for conflicting redeclarations and redefinitions. 776 } 777 778 // C: Function types need to be compatible, not identical. This handles 779 // duplicate function decls like "void f(int); void f(enum X);" properly. 780 if (!getLangOptions().CPlusPlus && 781 Context.typesAreCompatible(OldQType, NewQType)) { 782 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 783 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 784 const FunctionProtoType *OldProto = 0; 785 if (isa<FunctionNoProtoType>(NewFuncType) && 786 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 787 // The old declaration provided a function prototype, but the 788 // new declaration does not. Merge in the prototype. 789 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 790 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 791 OldProto->arg_type_end()); 792 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 793 ParamTypes.data(), ParamTypes.size(), 794 OldProto->isVariadic(), 795 OldProto->getTypeQuals()); 796 New->setType(NewQType); 797 New->setHasInheritedPrototype(); 798 799 // Synthesize a parameter for each argument type. 800 llvm::SmallVector<ParmVarDecl*, 16> Params; 801 for (FunctionProtoType::arg_type_iterator 802 ParamType = OldProto->arg_type_begin(), 803 ParamEnd = OldProto->arg_type_end(); 804 ParamType != ParamEnd; ++ParamType) { 805 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 806 SourceLocation(), 0, 807 *ParamType, /*DInfo=*/0, 808 VarDecl::None, 0); 809 Param->setImplicit(); 810 Params.push_back(Param); 811 } 812 813 New->setParams(Context, Params.data(), Params.size()); 814 } 815 816 return MergeCompatibleFunctionDecls(New, Old); 817 } 818 819 // GNU C permits a K&R definition to follow a prototype declaration 820 // if the declared types of the parameters in the K&R definition 821 // match the types in the prototype declaration, even when the 822 // promoted types of the parameters from the K&R definition differ 823 // from the types in the prototype. GCC then keeps the types from 824 // the prototype. 825 // 826 // If a variadic prototype is followed by a non-variadic K&R definition, 827 // the K&R definition becomes variadic. This is sort of an edge case, but 828 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 829 // C99 6.9.1p8. 830 if (!getLangOptions().CPlusPlus && 831 Old->hasPrototype() && !New->hasPrototype() && 832 New->getType()->getAs<FunctionProtoType>() && 833 Old->getNumParams() == New->getNumParams()) { 834 llvm::SmallVector<QualType, 16> ArgTypes; 835 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 836 const FunctionProtoType *OldProto 837 = Old->getType()->getAs<FunctionProtoType>(); 838 const FunctionProtoType *NewProto 839 = New->getType()->getAs<FunctionProtoType>(); 840 841 // Determine whether this is the GNU C extension. 842 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 843 NewProto->getResultType()); 844 bool LooseCompatible = !MergedReturn.isNull(); 845 for (unsigned Idx = 0, End = Old->getNumParams(); 846 LooseCompatible && Idx != End; ++Idx) { 847 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 848 ParmVarDecl *NewParm = New->getParamDecl(Idx); 849 if (Context.typesAreCompatible(OldParm->getType(), 850 NewProto->getArgType(Idx))) { 851 ArgTypes.push_back(NewParm->getType()); 852 } else if (Context.typesAreCompatible(OldParm->getType(), 853 NewParm->getType())) { 854 GNUCompatibleParamWarning Warn 855 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 856 Warnings.push_back(Warn); 857 ArgTypes.push_back(NewParm->getType()); 858 } else 859 LooseCompatible = false; 860 } 861 862 if (LooseCompatible) { 863 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 864 Diag(Warnings[Warn].NewParm->getLocation(), 865 diag::ext_param_promoted_not_compatible_with_prototype) 866 << Warnings[Warn].PromotedType 867 << Warnings[Warn].OldParm->getType(); 868 Diag(Warnings[Warn].OldParm->getLocation(), 869 diag::note_previous_declaration); 870 } 871 872 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 873 ArgTypes.size(), 874 OldProto->isVariadic(), 0)); 875 return MergeCompatibleFunctionDecls(New, Old); 876 } 877 878 // Fall through to diagnose conflicting types. 879 } 880 881 // A function that has already been declared has been redeclared or defined 882 // with a different type- show appropriate diagnostic 883 if (unsigned BuiltinID = Old->getBuiltinID()) { 884 // The user has declared a builtin function with an incompatible 885 // signature. 886 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 887 // The function the user is redeclaring is a library-defined 888 // function like 'malloc' or 'printf'. Warn about the 889 // redeclaration, then pretend that we don't know about this 890 // library built-in. 891 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 892 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 893 << Old << Old->getType(); 894 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 895 Old->setInvalidDecl(); 896 return false; 897 } 898 899 PrevDiag = diag::note_previous_builtin_declaration; 900 } 901 902 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 903 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 904 return true; 905} 906 907/// \brief Completes the merge of two function declarations that are 908/// known to be compatible. 909/// 910/// This routine handles the merging of attributes and other 911/// properties of function declarations form the old declaration to 912/// the new declaration, once we know that New is in fact a 913/// redeclaration of Old. 914/// 915/// \returns false 916bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 917 // Merge the attributes 918 MergeAttributes(New, Old, Context); 919 920 // Merge the storage class. 921 if (Old->getStorageClass() != FunctionDecl::Extern && 922 Old->getStorageClass() != FunctionDecl::None) 923 New->setStorageClass(Old->getStorageClass()); 924 925 // Merge "pure" flag. 926 if (Old->isPure()) 927 New->setPure(); 928 929 // Merge the "deleted" flag. 930 if (Old->isDeleted()) 931 New->setDeleted(); 932 933 if (getLangOptions().CPlusPlus) 934 return MergeCXXFunctionDecl(New, Old); 935 936 return false; 937} 938 939/// MergeVarDecl - We just parsed a variable 'New' which has the same name 940/// and scope as a previous declaration 'Old'. Figure out how to resolve this 941/// situation, merging decls or emitting diagnostics as appropriate. 942/// 943/// Tentative definition rules (C99 6.9.2p2) are checked by 944/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 945/// definitions here, since the initializer hasn't been attached. 946/// 947void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 948 // If either decl is invalid, make sure the new one is marked invalid and 949 // don't do any other checking. 950 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 951 return New->setInvalidDecl(); 952 953 // Verify the old decl was also a variable. 954 VarDecl *Old = dyn_cast<VarDecl>(OldD); 955 if (!Old) { 956 Diag(New->getLocation(), diag::err_redefinition_different_kind) 957 << New->getDeclName(); 958 Diag(OldD->getLocation(), diag::note_previous_definition); 959 return New->setInvalidDecl(); 960 } 961 962 MergeAttributes(New, Old, Context); 963 964 // Merge the types 965 QualType MergedT; 966 if (getLangOptions().CPlusPlus) { 967 if (Context.hasSameType(New->getType(), Old->getType())) 968 MergedT = New->getType(); 969 // C++ [basic.types]p7: 970 // [...] The declared type of an array object might be an array of 971 // unknown size and therefore be incomplete at one point in a 972 // translation unit and complete later on; [...] 973 else if (Old->getType()->isIncompleteArrayType() && 974 New->getType()->isArrayType()) { 975 CanQual<ArrayType> OldArray 976 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 977 CanQual<ArrayType> NewArray 978 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 979 if (OldArray->getElementType() == NewArray->getElementType()) 980 MergedT = New->getType(); 981 } 982 } else { 983 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 984 } 985 if (MergedT.isNull()) { 986 Diag(New->getLocation(), diag::err_redefinition_different_type) 987 << New->getDeclName(); 988 Diag(Old->getLocation(), diag::note_previous_definition); 989 return New->setInvalidDecl(); 990 } 991 New->setType(MergedT); 992 993 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 994 if (New->getStorageClass() == VarDecl::Static && 995 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 996 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 997 Diag(Old->getLocation(), diag::note_previous_definition); 998 return New->setInvalidDecl(); 999 } 1000 // C99 6.2.2p4: 1001 // For an identifier declared with the storage-class specifier 1002 // extern in a scope in which a prior declaration of that 1003 // identifier is visible,23) if the prior declaration specifies 1004 // internal or external linkage, the linkage of the identifier at 1005 // the later declaration is the same as the linkage specified at 1006 // the prior declaration. If no prior declaration is visible, or 1007 // if the prior declaration specifies no linkage, then the 1008 // identifier has external linkage. 1009 if (New->hasExternalStorage() && Old->hasLinkage()) 1010 /* Okay */; 1011 else if (New->getStorageClass() != VarDecl::Static && 1012 Old->getStorageClass() == VarDecl::Static) { 1013 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1014 Diag(Old->getLocation(), diag::note_previous_definition); 1015 return New->setInvalidDecl(); 1016 } 1017 1018 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1019 1020 // FIXME: The test for external storage here seems wrong? We still 1021 // need to check for mismatches. 1022 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1023 // Don't complain about out-of-line definitions of static members. 1024 !(Old->getLexicalDeclContext()->isRecord() && 1025 !New->getLexicalDeclContext()->isRecord())) { 1026 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1027 Diag(Old->getLocation(), diag::note_previous_definition); 1028 return New->setInvalidDecl(); 1029 } 1030 1031 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1032 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1033 Diag(Old->getLocation(), diag::note_previous_definition); 1034 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1035 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1036 Diag(Old->getLocation(), diag::note_previous_definition); 1037 } 1038 1039 // Keep a chain of previous declarations. 1040 New->setPreviousDeclaration(Old); 1041} 1042 1043/// CheckFallThrough - Check that we don't fall off the end of a 1044/// Statement that should return a value. 1045/// 1046/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1047/// MaybeFallThrough iff we might or might not fall off the end, 1048/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1049/// return. We assume NeverFallThrough iff we never fall off the end of the 1050/// statement but we may return. We assume that functions not marked noreturn 1051/// will return. 1052Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1053 // FIXME: Eventually share this CFG object when we have other warnings based 1054 // of the CFG. This can be done using AnalysisContext. 1055 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1056 1057 // FIXME: They should never return 0, fix that, delete this code. 1058 if (cfg == 0) 1059 // FIXME: This should be NeverFallThrough 1060 return NeverFallThroughOrReturn; 1061 // The CFG leaves in dead things, and we don't want to dead code paths to 1062 // confuse us, so we mark all live things first. 1063 std::queue<CFGBlock*> workq; 1064 llvm::BitVector live(cfg->getNumBlockIDs()); 1065 // Prep work queue 1066 workq.push(&cfg->getEntry()); 1067 // Solve 1068 while (!workq.empty()) { 1069 CFGBlock *item = workq.front(); 1070 workq.pop(); 1071 live.set(item->getBlockID()); 1072 for (CFGBlock::succ_iterator I=item->succ_begin(), 1073 E=item->succ_end(); 1074 I != E; 1075 ++I) { 1076 if ((*I) && !live[(*I)->getBlockID()]) { 1077 live.set((*I)->getBlockID()); 1078 workq.push(*I); 1079 } 1080 } 1081 } 1082 1083 // Now we know what is live, we check the live precessors of the exit block 1084 // and look for fall through paths, being careful to ignore normal returns, 1085 // and exceptional paths. 1086 bool HasLiveReturn = false; 1087 bool HasFakeEdge = false; 1088 bool HasPlainEdge = false; 1089 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1090 E = cfg->getExit().pred_end(); 1091 I != E; 1092 ++I) { 1093 CFGBlock& B = **I; 1094 if (!live[B.getBlockID()]) 1095 continue; 1096 if (B.size() == 0) { 1097 // A labeled empty statement, or the entry block... 1098 HasPlainEdge = true; 1099 continue; 1100 } 1101 Stmt *S = B[B.size()-1]; 1102 if (isa<ReturnStmt>(S)) { 1103 HasLiveReturn = true; 1104 continue; 1105 } 1106 if (isa<ObjCAtThrowStmt>(S)) { 1107 HasFakeEdge = true; 1108 continue; 1109 } 1110 if (isa<CXXThrowExpr>(S)) { 1111 HasFakeEdge = true; 1112 continue; 1113 } 1114 bool NoReturnEdge = false; 1115 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1116 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1117 if (CEE->getType().getNoReturnAttr()) { 1118 NoReturnEdge = true; 1119 HasFakeEdge = true; 1120 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1121 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1122 if (FD->hasAttr<NoReturnAttr>()) { 1123 NoReturnEdge = true; 1124 HasFakeEdge = true; 1125 } 1126 } 1127 } 1128 } 1129 // FIXME: Add noreturn message sends. 1130 if (NoReturnEdge == false) 1131 HasPlainEdge = true; 1132 } 1133 if (!HasPlainEdge) { 1134 if (HasLiveReturn) 1135 return NeverFallThrough; 1136 return NeverFallThroughOrReturn; 1137 } 1138 if (HasFakeEdge || HasLiveReturn) 1139 return MaybeFallThrough; 1140 // This says AlwaysFallThrough for calls to functions that are not marked 1141 // noreturn, that don't return. If people would like this warning to be more 1142 // accurate, such functions should be marked as noreturn. 1143 return AlwaysFallThrough; 1144} 1145 1146/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1147/// function that should return a value. Check that we don't fall off the end 1148/// of a noreturn function. We assume that functions and blocks not marked 1149/// noreturn will return. 1150void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1151 // FIXME: Would be nice if we had a better way to control cascading errors, 1152 // but for now, avoid them. The problem is that when Parse sees: 1153 // int foo() { return a; } 1154 // The return is eaten and the Sema code sees just: 1155 // int foo() { } 1156 // which this code would then warn about. 1157 if (getDiagnostics().hasErrorOccurred()) 1158 return; 1159 1160 bool ReturnsVoid = false; 1161 bool HasNoReturn = false; 1162 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1163 // If the result type of the function is a dependent type, we don't know 1164 // whether it will be void or not, so don't 1165 if (FD->getResultType()->isDependentType()) 1166 return; 1167 if (FD->getResultType()->isVoidType()) 1168 ReturnsVoid = true; 1169 if (FD->hasAttr<NoReturnAttr>()) 1170 HasNoReturn = true; 1171 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1172 if (MD->getResultType()->isVoidType()) 1173 ReturnsVoid = true; 1174 if (MD->hasAttr<NoReturnAttr>()) 1175 HasNoReturn = true; 1176 } 1177 1178 // Short circuit for compilation speed. 1179 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1180 == Diagnostic::Ignored || ReturnsVoid) 1181 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1182 == Diagnostic::Ignored || !HasNoReturn) 1183 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1184 == Diagnostic::Ignored || !ReturnsVoid)) 1185 return; 1186 // FIXME: Function try block 1187 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1188 switch (CheckFallThrough(Body)) { 1189 case MaybeFallThrough: 1190 if (HasNoReturn) 1191 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1192 else if (!ReturnsVoid) 1193 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1194 break; 1195 case AlwaysFallThrough: 1196 if (HasNoReturn) 1197 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1198 else if (!ReturnsVoid) 1199 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1200 break; 1201 case NeverFallThroughOrReturn: 1202 if (ReturnsVoid && !HasNoReturn) 1203 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1204 break; 1205 case NeverFallThrough: 1206 break; 1207 } 1208 } 1209} 1210 1211/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1212/// that should return a value. Check that we don't fall off the end of a 1213/// noreturn block. We assume that functions and blocks not marked noreturn 1214/// will return. 1215void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1216 // FIXME: Would be nice if we had a better way to control cascading errors, 1217 // but for now, avoid them. The problem is that when Parse sees: 1218 // int foo() { return a; } 1219 // The return is eaten and the Sema code sees just: 1220 // int foo() { } 1221 // which this code would then warn about. 1222 if (getDiagnostics().hasErrorOccurred()) 1223 return; 1224 bool ReturnsVoid = false; 1225 bool HasNoReturn = false; 1226 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1227 if (FT->getResultType()->isVoidType()) 1228 ReturnsVoid = true; 1229 if (FT->getNoReturnAttr()) 1230 HasNoReturn = true; 1231 } 1232 1233 // Short circuit for compilation speed. 1234 if (ReturnsVoid 1235 && !HasNoReturn 1236 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1237 == Diagnostic::Ignored || !ReturnsVoid)) 1238 return; 1239 // FIXME: Funtion try block 1240 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1241 switch (CheckFallThrough(Body)) { 1242 case MaybeFallThrough: 1243 if (HasNoReturn) 1244 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1245 else if (!ReturnsVoid) 1246 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1247 break; 1248 case AlwaysFallThrough: 1249 if (HasNoReturn) 1250 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1251 else if (!ReturnsVoid) 1252 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1253 break; 1254 case NeverFallThroughOrReturn: 1255 if (ReturnsVoid) 1256 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1257 break; 1258 case NeverFallThrough: 1259 break; 1260 } 1261 } 1262} 1263 1264/// CheckParmsForFunctionDef - Check that the parameters of the given 1265/// function are appropriate for the definition of a function. This 1266/// takes care of any checks that cannot be performed on the 1267/// declaration itself, e.g., that the types of each of the function 1268/// parameters are complete. 1269bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1270 bool HasInvalidParm = false; 1271 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1272 ParmVarDecl *Param = FD->getParamDecl(p); 1273 1274 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1275 // function declarator that is part of a function definition of 1276 // that function shall not have incomplete type. 1277 // 1278 // This is also C++ [dcl.fct]p6. 1279 if (!Param->isInvalidDecl() && 1280 RequireCompleteType(Param->getLocation(), Param->getType(), 1281 diag::err_typecheck_decl_incomplete_type)) { 1282 Param->setInvalidDecl(); 1283 HasInvalidParm = true; 1284 } 1285 1286 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1287 // declaration of each parameter shall include an identifier. 1288 if (Param->getIdentifier() == 0 && 1289 !Param->isImplicit() && 1290 !getLangOptions().CPlusPlus) 1291 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1292 } 1293 1294 return HasInvalidParm; 1295} 1296 1297/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1298/// no declarator (e.g. "struct foo;") is parsed. 1299Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1300 // FIXME: Error on auto/register at file scope 1301 // FIXME: Error on inline/virtual/explicit 1302 // FIXME: Error on invalid restrict 1303 // FIXME: Warn on useless __thread 1304 // FIXME: Warn on useless const/volatile 1305 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1306 // FIXME: Warn on useless attributes 1307 Decl *TagD = 0; 1308 TagDecl *Tag = 0; 1309 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1310 DS.getTypeSpecType() == DeclSpec::TST_struct || 1311 DS.getTypeSpecType() == DeclSpec::TST_union || 1312 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1313 TagD = static_cast<Decl *>(DS.getTypeRep()); 1314 1315 if (!TagD) // We probably had an error 1316 return DeclPtrTy(); 1317 1318 // Note that the above type specs guarantee that the 1319 // type rep is a Decl, whereas in many of the others 1320 // it's a Type. 1321 Tag = dyn_cast<TagDecl>(TagD); 1322 } 1323 1324 if (DS.isFriendSpecified()) { 1325 // If we're dealing with a class template decl, assume that the 1326 // template routines are handling it. 1327 if (TagD && isa<ClassTemplateDecl>(TagD)) 1328 return DeclPtrTy(); 1329 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1330 } 1331 1332 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1333 // If there are attributes in the DeclSpec, apply them to the record. 1334 if (const AttributeList *AL = DS.getAttributes()) 1335 ProcessDeclAttributeList(S, Record, AL); 1336 1337 if (!Record->getDeclName() && Record->isDefinition() && 1338 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1339 if (getLangOptions().CPlusPlus || 1340 Record->getDeclContext()->isRecord()) 1341 return BuildAnonymousStructOrUnion(S, DS, Record); 1342 1343 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1344 << DS.getSourceRange(); 1345 } 1346 1347 // Microsoft allows unnamed struct/union fields. Don't complain 1348 // about them. 1349 // FIXME: Should we support Microsoft's extensions in this area? 1350 if (Record->getDeclName() && getLangOptions().Microsoft) 1351 return DeclPtrTy::make(Tag); 1352 } 1353 1354 if (!DS.isMissingDeclaratorOk() && 1355 DS.getTypeSpecType() != DeclSpec::TST_error) { 1356 // Warn about typedefs of enums without names, since this is an 1357 // extension in both Microsoft an GNU. 1358 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1359 Tag && isa<EnumDecl>(Tag)) { 1360 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1361 << DS.getSourceRange(); 1362 return DeclPtrTy::make(Tag); 1363 } 1364 1365 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1366 << DS.getSourceRange(); 1367 return DeclPtrTy(); 1368 } 1369 1370 return DeclPtrTy::make(Tag); 1371} 1372 1373/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1374/// anonymous struct or union AnonRecord into the owning context Owner 1375/// and scope S. This routine will be invoked just after we realize 1376/// that an unnamed union or struct is actually an anonymous union or 1377/// struct, e.g., 1378/// 1379/// @code 1380/// union { 1381/// int i; 1382/// float f; 1383/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1384/// // f into the surrounding scope.x 1385/// @endcode 1386/// 1387/// This routine is recursive, injecting the names of nested anonymous 1388/// structs/unions into the owning context and scope as well. 1389bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1390 RecordDecl *AnonRecord) { 1391 bool Invalid = false; 1392 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1393 FEnd = AnonRecord->field_end(); 1394 F != FEnd; ++F) { 1395 if ((*F)->getDeclName()) { 1396 LookupResult R; 1397 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1398 LookupOrdinaryName, true); 1399 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1400 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1401 // C++ [class.union]p2: 1402 // The names of the members of an anonymous union shall be 1403 // distinct from the names of any other entity in the 1404 // scope in which the anonymous union is declared. 1405 unsigned diagKind 1406 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1407 : diag::err_anonymous_struct_member_redecl; 1408 Diag((*F)->getLocation(), diagKind) 1409 << (*F)->getDeclName(); 1410 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1411 Invalid = true; 1412 } else { 1413 // C++ [class.union]p2: 1414 // For the purpose of name lookup, after the anonymous union 1415 // definition, the members of the anonymous union are 1416 // considered to have been defined in the scope in which the 1417 // anonymous union is declared. 1418 Owner->makeDeclVisibleInContext(*F); 1419 S->AddDecl(DeclPtrTy::make(*F)); 1420 IdResolver.AddDecl(*F); 1421 } 1422 } else if (const RecordType *InnerRecordType 1423 = (*F)->getType()->getAs<RecordType>()) { 1424 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1425 if (InnerRecord->isAnonymousStructOrUnion()) 1426 Invalid = Invalid || 1427 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1428 } 1429 } 1430 1431 return Invalid; 1432} 1433 1434/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1435/// anonymous structure or union. Anonymous unions are a C++ feature 1436/// (C++ [class.union]) and a GNU C extension; anonymous structures 1437/// are a GNU C and GNU C++ extension. 1438Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1439 RecordDecl *Record) { 1440 DeclContext *Owner = Record->getDeclContext(); 1441 1442 // Diagnose whether this anonymous struct/union is an extension. 1443 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1444 Diag(Record->getLocation(), diag::ext_anonymous_union); 1445 else if (!Record->isUnion()) 1446 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1447 1448 // C and C++ require different kinds of checks for anonymous 1449 // structs/unions. 1450 bool Invalid = false; 1451 if (getLangOptions().CPlusPlus) { 1452 const char* PrevSpec = 0; 1453 unsigned DiagID; 1454 // C++ [class.union]p3: 1455 // Anonymous unions declared in a named namespace or in the 1456 // global namespace shall be declared static. 1457 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1458 (isa<TranslationUnitDecl>(Owner) || 1459 (isa<NamespaceDecl>(Owner) && 1460 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1461 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1462 Invalid = true; 1463 1464 // Recover by adding 'static'. 1465 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1466 PrevSpec, DiagID); 1467 } 1468 // C++ [class.union]p3: 1469 // A storage class is not allowed in a declaration of an 1470 // anonymous union in a class scope. 1471 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1472 isa<RecordDecl>(Owner)) { 1473 Diag(DS.getStorageClassSpecLoc(), 1474 diag::err_anonymous_union_with_storage_spec); 1475 Invalid = true; 1476 1477 // Recover by removing the storage specifier. 1478 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1479 PrevSpec, DiagID); 1480 } 1481 1482 // C++ [class.union]p2: 1483 // The member-specification of an anonymous union shall only 1484 // define non-static data members. [Note: nested types and 1485 // functions cannot be declared within an anonymous union. ] 1486 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1487 MemEnd = Record->decls_end(); 1488 Mem != MemEnd; ++Mem) { 1489 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1490 // C++ [class.union]p3: 1491 // An anonymous union shall not have private or protected 1492 // members (clause 11). 1493 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1494 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1495 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1496 Invalid = true; 1497 } 1498 } else if ((*Mem)->isImplicit()) { 1499 // Any implicit members are fine. 1500 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1501 // This is a type that showed up in an 1502 // elaborated-type-specifier inside the anonymous struct or 1503 // union, but which actually declares a type outside of the 1504 // anonymous struct or union. It's okay. 1505 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1506 if (!MemRecord->isAnonymousStructOrUnion() && 1507 MemRecord->getDeclName()) { 1508 // This is a nested type declaration. 1509 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1510 << (int)Record->isUnion(); 1511 Invalid = true; 1512 } 1513 } else { 1514 // We have something that isn't a non-static data 1515 // member. Complain about it. 1516 unsigned DK = diag::err_anonymous_record_bad_member; 1517 if (isa<TypeDecl>(*Mem)) 1518 DK = diag::err_anonymous_record_with_type; 1519 else if (isa<FunctionDecl>(*Mem)) 1520 DK = diag::err_anonymous_record_with_function; 1521 else if (isa<VarDecl>(*Mem)) 1522 DK = diag::err_anonymous_record_with_static; 1523 Diag((*Mem)->getLocation(), DK) 1524 << (int)Record->isUnion(); 1525 Invalid = true; 1526 } 1527 } 1528 } 1529 1530 if (!Record->isUnion() && !Owner->isRecord()) { 1531 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1532 << (int)getLangOptions().CPlusPlus; 1533 Invalid = true; 1534 } 1535 1536 // Mock up a declarator. 1537 Declarator Dc(DS, Declarator::TypeNameContext); 1538 DeclaratorInfo *DInfo = 0; 1539 GetTypeForDeclarator(Dc, S, &DInfo); 1540 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1541 1542 // Create a declaration for this anonymous struct/union. 1543 NamedDecl *Anon = 0; 1544 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1545 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1546 /*IdentifierInfo=*/0, 1547 Context.getTypeDeclType(Record), 1548 DInfo, 1549 /*BitWidth=*/0, /*Mutable=*/false); 1550 Anon->setAccess(AS_public); 1551 if (getLangOptions().CPlusPlus) 1552 FieldCollector->Add(cast<FieldDecl>(Anon)); 1553 } else { 1554 VarDecl::StorageClass SC; 1555 switch (DS.getStorageClassSpec()) { 1556 default: assert(0 && "Unknown storage class!"); 1557 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1558 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1559 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1560 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1561 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1562 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1563 case DeclSpec::SCS_mutable: 1564 // mutable can only appear on non-static class members, so it's always 1565 // an error here 1566 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1567 Invalid = true; 1568 SC = VarDecl::None; 1569 break; 1570 } 1571 1572 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1573 /*IdentifierInfo=*/0, 1574 Context.getTypeDeclType(Record), 1575 DInfo, 1576 SC); 1577 } 1578 Anon->setImplicit(); 1579 1580 // Add the anonymous struct/union object to the current 1581 // context. We'll be referencing this object when we refer to one of 1582 // its members. 1583 Owner->addDecl(Anon); 1584 1585 // Inject the members of the anonymous struct/union into the owning 1586 // context and into the identifier resolver chain for name lookup 1587 // purposes. 1588 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1589 Invalid = true; 1590 1591 // Mark this as an anonymous struct/union type. Note that we do not 1592 // do this until after we have already checked and injected the 1593 // members of this anonymous struct/union type, because otherwise 1594 // the members could be injected twice: once by DeclContext when it 1595 // builds its lookup table, and once by 1596 // InjectAnonymousStructOrUnionMembers. 1597 Record->setAnonymousStructOrUnion(true); 1598 1599 if (Invalid) 1600 Anon->setInvalidDecl(); 1601 1602 return DeclPtrTy::make(Anon); 1603} 1604 1605 1606/// GetNameForDeclarator - Determine the full declaration name for the 1607/// given Declarator. 1608DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1609 return GetNameFromUnqualifiedId(D.getName()); 1610} 1611 1612/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1613DeclarationName Sema::GetNameFromUnqualifiedId(UnqualifiedId &Name) { 1614 switch (Name.getKind()) { 1615 case UnqualifiedId::IK_Identifier: 1616 return DeclarationName(Name.Identifier); 1617 1618 case UnqualifiedId::IK_OperatorFunctionId: 1619 return Context.DeclarationNames.getCXXOperatorName( 1620 Name.OperatorFunctionId.Operator); 1621 1622 case UnqualifiedId::IK_ConversionFunctionId: { 1623 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1624 if (Ty.isNull()) 1625 return DeclarationName(); 1626 1627 return Context.DeclarationNames.getCXXConversionFunctionName( 1628 Context.getCanonicalType(Ty)); 1629 } 1630 1631 case UnqualifiedId::IK_ConstructorName: { 1632 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1633 if (Ty.isNull()) 1634 return DeclarationName(); 1635 1636 return Context.DeclarationNames.getCXXConstructorName( 1637 Context.getCanonicalType(Ty)); 1638 } 1639 1640 case UnqualifiedId::IK_DestructorName: { 1641 QualType Ty = GetTypeFromParser(Name.DestructorName); 1642 if (Ty.isNull()) 1643 return DeclarationName(); 1644 1645 return Context.DeclarationNames.getCXXDestructorName( 1646 Context.getCanonicalType(Ty)); 1647 } 1648 1649 case UnqualifiedId::IK_TemplateId: { 1650 TemplateName TName 1651 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1652 if (TemplateDecl *Template = TName.getAsTemplateDecl()) 1653 return Template->getDeclName(); 1654 if (OverloadedFunctionDecl *Ovl = TName.getAsOverloadedFunctionDecl()) 1655 return Ovl->getDeclName(); 1656 1657 return DeclarationName(); 1658 } 1659 } 1660 1661 assert(false && "Unknown name kind"); 1662 return DeclarationName(); 1663} 1664 1665/// isNearlyMatchingFunction - Determine whether the C++ functions 1666/// Declaration and Definition are "nearly" matching. This heuristic 1667/// is used to improve diagnostics in the case where an out-of-line 1668/// function definition doesn't match any declaration within 1669/// the class or namespace. 1670static bool isNearlyMatchingFunction(ASTContext &Context, 1671 FunctionDecl *Declaration, 1672 FunctionDecl *Definition) { 1673 if (Declaration->param_size() != Definition->param_size()) 1674 return false; 1675 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1676 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1677 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1678 1679 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1680 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1681 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1682 return false; 1683 } 1684 1685 return true; 1686} 1687 1688Sema::DeclPtrTy 1689Sema::HandleDeclarator(Scope *S, Declarator &D, 1690 MultiTemplateParamsArg TemplateParamLists, 1691 bool IsFunctionDefinition) { 1692 DeclarationName Name = GetNameForDeclarator(D); 1693 1694 // All of these full declarators require an identifier. If it doesn't have 1695 // one, the ParsedFreeStandingDeclSpec action should be used. 1696 if (!Name) { 1697 if (!D.isInvalidType()) // Reject this if we think it is valid. 1698 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1699 diag::err_declarator_need_ident) 1700 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1701 return DeclPtrTy(); 1702 } 1703 1704 // The scope passed in may not be a decl scope. Zip up the scope tree until 1705 // we find one that is. 1706 while ((S->getFlags() & Scope::DeclScope) == 0 || 1707 (S->getFlags() & Scope::TemplateParamScope) != 0) 1708 S = S->getParent(); 1709 1710 // If this is an out-of-line definition of a member of a class template 1711 // or class template partial specialization, we may need to rebuild the 1712 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1713 // for more information. 1714 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1715 // handle expressions properly. 1716 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1717 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1718 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1719 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1720 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1721 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1722 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1723 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1724 // FIXME: Preserve type source info. 1725 QualType T = GetTypeFromParser(DS.getTypeRep()); 1726 EnterDeclaratorContext(S, DC); 1727 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1728 ExitDeclaratorContext(S); 1729 if (T.isNull()) 1730 return DeclPtrTy(); 1731 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1732 } 1733 } 1734 1735 DeclContext *DC; 1736 NamedDecl *PrevDecl; 1737 NamedDecl *New; 1738 1739 DeclaratorInfo *DInfo = 0; 1740 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1741 1742 // See if this is a redefinition of a variable in the same scope. 1743 if (D.getCXXScopeSpec().isInvalid()) { 1744 DC = CurContext; 1745 PrevDecl = 0; 1746 D.setInvalidType(); 1747 } else if (!D.getCXXScopeSpec().isSet()) { 1748 LookupNameKind NameKind = LookupOrdinaryName; 1749 1750 // If the declaration we're planning to build will be a function 1751 // or object with linkage, then look for another declaration with 1752 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1753 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1754 /* Do nothing*/; 1755 else if (R->isFunctionType()) { 1756 if (CurContext->isFunctionOrMethod() || 1757 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1758 NameKind = LookupRedeclarationWithLinkage; 1759 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1760 NameKind = LookupRedeclarationWithLinkage; 1761 else if (CurContext->getLookupContext()->isTranslationUnit() && 1762 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1763 NameKind = LookupRedeclarationWithLinkage; 1764 1765 DC = CurContext; 1766 LookupResult R; 1767 LookupName(R, S, Name, NameKind, true, 1768 NameKind == LookupRedeclarationWithLinkage, 1769 D.getIdentifierLoc()); 1770 PrevDecl = R.getAsSingleDecl(Context); 1771 } else { // Something like "int foo::x;" 1772 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1773 1774 if (!DC) { 1775 // If we could not compute the declaration context, it's because the 1776 // declaration context is dependent but does not refer to a class, 1777 // class template, or class template partial specialization. Complain 1778 // and return early, to avoid the coming semantic disaster. 1779 Diag(D.getIdentifierLoc(), 1780 diag::err_template_qualified_declarator_no_match) 1781 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1782 << D.getCXXScopeSpec().getRange(); 1783 return DeclPtrTy(); 1784 } 1785 1786 if (!DC->isDependentContext() && 1787 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1788 return DeclPtrTy(); 1789 1790 LookupResult Res; 1791 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1792 PrevDecl = Res.getAsSingleDecl(Context); 1793 1794 // C++ 7.3.1.2p2: 1795 // Members (including explicit specializations of templates) of a named 1796 // namespace can also be defined outside that namespace by explicit 1797 // qualification of the name being defined, provided that the entity being 1798 // defined was already declared in the namespace and the definition appears 1799 // after the point of declaration in a namespace that encloses the 1800 // declarations namespace. 1801 // 1802 // Note that we only check the context at this point. We don't yet 1803 // have enough information to make sure that PrevDecl is actually 1804 // the declaration we want to match. For example, given: 1805 // 1806 // class X { 1807 // void f(); 1808 // void f(float); 1809 // }; 1810 // 1811 // void X::f(int) { } // ill-formed 1812 // 1813 // In this case, PrevDecl will point to the overload set 1814 // containing the two f's declared in X, but neither of them 1815 // matches. 1816 1817 // First check whether we named the global scope. 1818 if (isa<TranslationUnitDecl>(DC)) { 1819 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1820 << Name << D.getCXXScopeSpec().getRange(); 1821 } else if (!CurContext->Encloses(DC)) { 1822 // The qualifying scope doesn't enclose the original declaration. 1823 // Emit diagnostic based on current scope. 1824 SourceLocation L = D.getIdentifierLoc(); 1825 SourceRange R = D.getCXXScopeSpec().getRange(); 1826 if (isa<FunctionDecl>(CurContext)) 1827 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1828 else 1829 Diag(L, diag::err_invalid_declarator_scope) 1830 << Name << cast<NamedDecl>(DC) << R; 1831 D.setInvalidType(); 1832 } 1833 } 1834 1835 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1836 // Maybe we will complain about the shadowed template parameter. 1837 if (!D.isInvalidType()) 1838 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1839 D.setInvalidType(); 1840 1841 // Just pretend that we didn't see the previous declaration. 1842 PrevDecl = 0; 1843 } 1844 1845 // In C++, the previous declaration we find might be a tag type 1846 // (class or enum). In this case, the new declaration will hide the 1847 // tag type. Note that this does does not apply if we're declaring a 1848 // typedef (C++ [dcl.typedef]p4). 1849 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1850 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1851 PrevDecl = 0; 1852 1853 bool Redeclaration = false; 1854 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1855 if (TemplateParamLists.size()) { 1856 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1857 return DeclPtrTy(); 1858 } 1859 1860 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1861 } else if (R->isFunctionType()) { 1862 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1863 move(TemplateParamLists), 1864 IsFunctionDefinition, Redeclaration); 1865 } else { 1866 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1867 move(TemplateParamLists), 1868 Redeclaration); 1869 } 1870 1871 if (New == 0) 1872 return DeclPtrTy(); 1873 1874 // If this has an identifier and is not an invalid redeclaration or 1875 // function template specialization, add it to the scope stack. 1876 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1877 !(isa<FunctionDecl>(New) && 1878 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1879 PushOnScopeChains(New, S); 1880 1881 return DeclPtrTy::make(New); 1882} 1883 1884/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1885/// types into constant array types in certain situations which would otherwise 1886/// be errors (for GCC compatibility). 1887static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1888 ASTContext &Context, 1889 bool &SizeIsNegative) { 1890 // This method tries to turn a variable array into a constant 1891 // array even when the size isn't an ICE. This is necessary 1892 // for compatibility with code that depends on gcc's buggy 1893 // constant expression folding, like struct {char x[(int)(char*)2];} 1894 SizeIsNegative = false; 1895 1896 QualifierCollector Qs; 1897 const Type *Ty = Qs.strip(T); 1898 1899 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1900 QualType Pointee = PTy->getPointeeType(); 1901 QualType FixedType = 1902 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1903 if (FixedType.isNull()) return FixedType; 1904 FixedType = Context.getPointerType(FixedType); 1905 return Qs.apply(FixedType); 1906 } 1907 1908 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1909 if (!VLATy) 1910 return QualType(); 1911 // FIXME: We should probably handle this case 1912 if (VLATy->getElementType()->isVariablyModifiedType()) 1913 return QualType(); 1914 1915 Expr::EvalResult EvalResult; 1916 if (!VLATy->getSizeExpr() || 1917 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1918 !EvalResult.Val.isInt()) 1919 return QualType(); 1920 1921 llvm::APSInt &Res = EvalResult.Val.getInt(); 1922 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1923 // TODO: preserve the size expression in declarator info 1924 return Context.getConstantArrayType(VLATy->getElementType(), 1925 Res, ArrayType::Normal, 0); 1926 } 1927 1928 SizeIsNegative = true; 1929 return QualType(); 1930} 1931 1932/// \brief Register the given locally-scoped external C declaration so 1933/// that it can be found later for redeclarations 1934void 1935Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1936 Scope *S) { 1937 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1938 "Decl is not a locally-scoped decl!"); 1939 // Note that we have a locally-scoped external with this name. 1940 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1941 1942 if (!PrevDecl) 1943 return; 1944 1945 // If there was a previous declaration of this variable, it may be 1946 // in our identifier chain. Update the identifier chain with the new 1947 // declaration. 1948 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1949 // The previous declaration was found on the identifer resolver 1950 // chain, so remove it from its scope. 1951 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1952 S = S->getParent(); 1953 1954 if (S) 1955 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1956 } 1957} 1958 1959/// \brief Diagnose function specifiers on a declaration of an identifier that 1960/// does not identify a function. 1961void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1962 // FIXME: We should probably indicate the identifier in question to avoid 1963 // confusion for constructs like "inline int a(), b;" 1964 if (D.getDeclSpec().isInlineSpecified()) 1965 Diag(D.getDeclSpec().getInlineSpecLoc(), 1966 diag::err_inline_non_function); 1967 1968 if (D.getDeclSpec().isVirtualSpecified()) 1969 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1970 diag::err_virtual_non_function); 1971 1972 if (D.getDeclSpec().isExplicitSpecified()) 1973 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1974 diag::err_explicit_non_function); 1975} 1976 1977NamedDecl* 1978Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1979 QualType R, DeclaratorInfo *DInfo, 1980 NamedDecl* PrevDecl, bool &Redeclaration) { 1981 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1982 if (D.getCXXScopeSpec().isSet()) { 1983 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1984 << D.getCXXScopeSpec().getRange(); 1985 D.setInvalidType(); 1986 // Pretend we didn't see the scope specifier. 1987 DC = 0; 1988 } 1989 1990 if (getLangOptions().CPlusPlus) { 1991 // Check that there are no default arguments (C++ only). 1992 CheckExtraCXXDefaultArguments(D); 1993 } 1994 1995 DiagnoseFunctionSpecifiers(D); 1996 1997 if (D.getDeclSpec().isThreadSpecified()) 1998 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1999 2000 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 2001 if (!NewTD) return 0; 2002 2003 // Handle attributes prior to checking for duplicates in MergeVarDecl 2004 ProcessDeclAttributes(S, NewTD, D); 2005 // Merge the decl with the existing one if appropriate. If the decl is 2006 // in an outer scope, it isn't the same thing. 2007 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2008 Redeclaration = true; 2009 MergeTypeDefDecl(NewTD, PrevDecl); 2010 } 2011 2012 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2013 // then it shall have block scope. 2014 QualType T = NewTD->getUnderlyingType(); 2015 if (T->isVariablyModifiedType()) { 2016 CurFunctionNeedsScopeChecking = true; 2017 2018 if (S->getFnParent() == 0) { 2019 bool SizeIsNegative; 2020 QualType FixedTy = 2021 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2022 if (!FixedTy.isNull()) { 2023 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2024 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2025 } else { 2026 if (SizeIsNegative) 2027 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2028 else if (T->isVariableArrayType()) 2029 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2030 else 2031 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2032 NewTD->setInvalidDecl(); 2033 } 2034 } 2035 } 2036 2037 // If this is the C FILE type, notify the AST context. 2038 if (IdentifierInfo *II = NewTD->getIdentifier()) 2039 if (!NewTD->isInvalidDecl() && 2040 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2041 if (II->isStr("FILE")) 2042 Context.setFILEDecl(NewTD); 2043 else if (II->isStr("jmp_buf")) 2044 Context.setjmp_bufDecl(NewTD); 2045 else if (II->isStr("sigjmp_buf")) 2046 Context.setsigjmp_bufDecl(NewTD); 2047 } 2048 2049 return NewTD; 2050} 2051 2052/// \brief Determines whether the given declaration is an out-of-scope 2053/// previous declaration. 2054/// 2055/// This routine should be invoked when name lookup has found a 2056/// previous declaration (PrevDecl) that is not in the scope where a 2057/// new declaration by the same name is being introduced. If the new 2058/// declaration occurs in a local scope, previous declarations with 2059/// linkage may still be considered previous declarations (C99 2060/// 6.2.2p4-5, C++ [basic.link]p6). 2061/// 2062/// \param PrevDecl the previous declaration found by name 2063/// lookup 2064/// 2065/// \param DC the context in which the new declaration is being 2066/// declared. 2067/// 2068/// \returns true if PrevDecl is an out-of-scope previous declaration 2069/// for a new delcaration with the same name. 2070static bool 2071isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2072 ASTContext &Context) { 2073 if (!PrevDecl) 2074 return 0; 2075 2076 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2077 // case we need to check each of the overloaded functions. 2078 if (!PrevDecl->hasLinkage()) 2079 return false; 2080 2081 if (Context.getLangOptions().CPlusPlus) { 2082 // C++ [basic.link]p6: 2083 // If there is a visible declaration of an entity with linkage 2084 // having the same name and type, ignoring entities declared 2085 // outside the innermost enclosing namespace scope, the block 2086 // scope declaration declares that same entity and receives the 2087 // linkage of the previous declaration. 2088 DeclContext *OuterContext = DC->getLookupContext(); 2089 if (!OuterContext->isFunctionOrMethod()) 2090 // This rule only applies to block-scope declarations. 2091 return false; 2092 else { 2093 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2094 if (PrevOuterContext->isRecord()) 2095 // We found a member function: ignore it. 2096 return false; 2097 else { 2098 // Find the innermost enclosing namespace for the new and 2099 // previous declarations. 2100 while (!OuterContext->isFileContext()) 2101 OuterContext = OuterContext->getParent(); 2102 while (!PrevOuterContext->isFileContext()) 2103 PrevOuterContext = PrevOuterContext->getParent(); 2104 2105 // The previous declaration is in a different namespace, so it 2106 // isn't the same function. 2107 if (OuterContext->getPrimaryContext() != 2108 PrevOuterContext->getPrimaryContext()) 2109 return false; 2110 } 2111 } 2112 } 2113 2114 return true; 2115} 2116 2117NamedDecl* 2118Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2119 QualType R, DeclaratorInfo *DInfo, 2120 NamedDecl* PrevDecl, 2121 MultiTemplateParamsArg TemplateParamLists, 2122 bool &Redeclaration) { 2123 DeclarationName Name = GetNameForDeclarator(D); 2124 2125 // Check that there are no default arguments (C++ only). 2126 if (getLangOptions().CPlusPlus) 2127 CheckExtraCXXDefaultArguments(D); 2128 2129 VarDecl *NewVD; 2130 VarDecl::StorageClass SC; 2131 switch (D.getDeclSpec().getStorageClassSpec()) { 2132 default: assert(0 && "Unknown storage class!"); 2133 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2134 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2135 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2136 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2137 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2138 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2139 case DeclSpec::SCS_mutable: 2140 // mutable can only appear on non-static class members, so it's always 2141 // an error here 2142 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2143 D.setInvalidType(); 2144 SC = VarDecl::None; 2145 break; 2146 } 2147 2148 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2149 if (!II) { 2150 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2151 << Name.getAsString(); 2152 return 0; 2153 } 2154 2155 DiagnoseFunctionSpecifiers(D); 2156 2157 if (!DC->isRecord() && S->getFnParent() == 0) { 2158 // C99 6.9p2: The storage-class specifiers auto and register shall not 2159 // appear in the declaration specifiers in an external declaration. 2160 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2161 2162 // If this is a register variable with an asm label specified, then this 2163 // is a GNU extension. 2164 if (SC == VarDecl::Register && D.getAsmLabel()) 2165 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2166 else 2167 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2168 D.setInvalidType(); 2169 } 2170 } 2171 if (DC->isRecord() && !CurContext->isRecord()) { 2172 // This is an out-of-line definition of a static data member. 2173 if (SC == VarDecl::Static) { 2174 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2175 diag::err_static_out_of_line) 2176 << CodeModificationHint::CreateRemoval( 2177 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2178 } else if (SC == VarDecl::None) 2179 SC = VarDecl::Static; 2180 } 2181 if (SC == VarDecl::Static) { 2182 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2183 if (RD->isLocalClass()) 2184 Diag(D.getIdentifierLoc(), 2185 diag::err_static_data_member_not_allowed_in_local_class) 2186 << Name << RD->getDeclName(); 2187 } 2188 } 2189 2190 // Match up the template parameter lists with the scope specifier, then 2191 // determine whether we have a template or a template specialization. 2192 bool isExplicitSpecialization = false; 2193 if (TemplateParameterList *TemplateParams 2194 = MatchTemplateParametersToScopeSpecifier( 2195 D.getDeclSpec().getSourceRange().getBegin(), 2196 D.getCXXScopeSpec(), 2197 (TemplateParameterList**)TemplateParamLists.get(), 2198 TemplateParamLists.size(), 2199 isExplicitSpecialization)) { 2200 if (TemplateParams->size() > 0) { 2201 // There is no such thing as a variable template. 2202 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2203 << II 2204 << SourceRange(TemplateParams->getTemplateLoc(), 2205 TemplateParams->getRAngleLoc()); 2206 return 0; 2207 } else { 2208 // There is an extraneous 'template<>' for this variable. Complain 2209 // about it, but allow the declaration of the variable. 2210 Diag(TemplateParams->getTemplateLoc(), 2211 diag::err_template_variable_noparams) 2212 << II 2213 << SourceRange(TemplateParams->getTemplateLoc(), 2214 TemplateParams->getRAngleLoc()); 2215 2216 isExplicitSpecialization = true; 2217 } 2218 } 2219 2220 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2221 II, R, DInfo, SC); 2222 2223 if (D.isInvalidType()) 2224 NewVD->setInvalidDecl(); 2225 2226 if (D.getDeclSpec().isThreadSpecified()) { 2227 if (NewVD->hasLocalStorage()) 2228 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2229 else if (!Context.Target.isTLSSupported()) 2230 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2231 else 2232 NewVD->setThreadSpecified(true); 2233 } 2234 2235 // Set the lexical context. If the declarator has a C++ scope specifier, the 2236 // lexical context will be different from the semantic context. 2237 NewVD->setLexicalDeclContext(CurContext); 2238 2239 // Handle attributes prior to checking for duplicates in MergeVarDecl 2240 ProcessDeclAttributes(S, NewVD, D); 2241 2242 // Handle GNU asm-label extension (encoded as an attribute). 2243 if (Expr *E = (Expr*) D.getAsmLabel()) { 2244 // The parser guarantees this is a string. 2245 StringLiteral *SE = cast<StringLiteral>(E); 2246 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2247 SE->getByteLength()))); 2248 } 2249 2250 // If name lookup finds a previous declaration that is not in the 2251 // same scope as the new declaration, this may still be an 2252 // acceptable redeclaration. 2253 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2254 !(NewVD->hasLinkage() && 2255 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2256 PrevDecl = 0; 2257 2258 // Merge the decl with the existing one if appropriate. 2259 if (PrevDecl) { 2260 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2261 // The user tried to define a non-static data member 2262 // out-of-line (C++ [dcl.meaning]p1). 2263 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2264 << D.getCXXScopeSpec().getRange(); 2265 PrevDecl = 0; 2266 NewVD->setInvalidDecl(); 2267 } 2268 } else if (D.getCXXScopeSpec().isSet()) { 2269 // No previous declaration in the qualifying scope. 2270 Diag(D.getIdentifierLoc(), diag::err_no_member) 2271 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2272 << D.getCXXScopeSpec().getRange(); 2273 NewVD->setInvalidDecl(); 2274 } 2275 2276 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2277 2278 // This is an explicit specialization of a static data member. Check it. 2279 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2280 CheckMemberSpecialization(NewVD, PrevDecl)) 2281 NewVD->setInvalidDecl(); 2282 2283 // attributes declared post-definition are currently ignored 2284 if (PrevDecl) { 2285 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2286 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2287 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2288 Diag(Def->getLocation(), diag::note_previous_definition); 2289 } 2290 } 2291 2292 // If this is a locally-scoped extern C variable, update the map of 2293 // such variables. 2294 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2295 !NewVD->isInvalidDecl()) 2296 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2297 2298 return NewVD; 2299} 2300 2301/// \brief Perform semantic checking on a newly-created variable 2302/// declaration. 2303/// 2304/// This routine performs all of the type-checking required for a 2305/// variable declaration once it has been built. It is used both to 2306/// check variables after they have been parsed and their declarators 2307/// have been translated into a declaration, and to check variables 2308/// that have been instantiated from a template. 2309/// 2310/// Sets NewVD->isInvalidDecl() if an error was encountered. 2311void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2312 bool &Redeclaration) { 2313 // If the decl is already known invalid, don't check it. 2314 if (NewVD->isInvalidDecl()) 2315 return; 2316 2317 QualType T = NewVD->getType(); 2318 2319 if (T->isObjCInterfaceType()) { 2320 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2321 return NewVD->setInvalidDecl(); 2322 } 2323 2324 // The variable can not have an abstract class type. 2325 if (RequireNonAbstractType(NewVD->getLocation(), T, 2326 diag::err_abstract_type_in_decl, 2327 AbstractVariableType)) 2328 return NewVD->setInvalidDecl(); 2329 2330 // Emit an error if an address space was applied to decl with local storage. 2331 // This includes arrays of objects with address space qualifiers, but not 2332 // automatic variables that point to other address spaces. 2333 // ISO/IEC TR 18037 S5.1.2 2334 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2335 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2336 return NewVD->setInvalidDecl(); 2337 } 2338 2339 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2340 && !NewVD->hasAttr<BlocksAttr>()) 2341 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2342 2343 bool isVM = T->isVariablyModifiedType(); 2344 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2345 NewVD->hasAttr<BlocksAttr>()) 2346 CurFunctionNeedsScopeChecking = true; 2347 2348 if ((isVM && NewVD->hasLinkage()) || 2349 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2350 bool SizeIsNegative; 2351 QualType FixedTy = 2352 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2353 2354 if (FixedTy.isNull() && T->isVariableArrayType()) { 2355 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2356 // FIXME: This won't give the correct result for 2357 // int a[10][n]; 2358 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2359 2360 if (NewVD->isFileVarDecl()) 2361 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2362 << SizeRange; 2363 else if (NewVD->getStorageClass() == VarDecl::Static) 2364 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2365 << SizeRange; 2366 else 2367 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2368 << SizeRange; 2369 return NewVD->setInvalidDecl(); 2370 } 2371 2372 if (FixedTy.isNull()) { 2373 if (NewVD->isFileVarDecl()) 2374 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2375 else 2376 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2377 return NewVD->setInvalidDecl(); 2378 } 2379 2380 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2381 NewVD->setType(FixedTy); 2382 } 2383 2384 if (!PrevDecl && NewVD->isExternC()) { 2385 // Since we did not find anything by this name and we're declaring 2386 // an extern "C" variable, look for a non-visible extern "C" 2387 // declaration with the same name. 2388 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2389 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2390 if (Pos != LocallyScopedExternalDecls.end()) 2391 PrevDecl = Pos->second; 2392 } 2393 2394 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2395 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2396 << T; 2397 return NewVD->setInvalidDecl(); 2398 } 2399 2400 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2401 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2402 return NewVD->setInvalidDecl(); 2403 } 2404 2405 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2406 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2407 return NewVD->setInvalidDecl(); 2408 } 2409 2410 if (PrevDecl) { 2411 Redeclaration = true; 2412 MergeVarDecl(NewVD, PrevDecl); 2413 } 2414} 2415 2416static bool isUsingDecl(Decl *D) { 2417 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2418} 2419 2420/// \brief Data used with FindOverriddenMethod 2421struct FindOverriddenMethodData { 2422 Sema *S; 2423 CXXMethodDecl *Method; 2424}; 2425 2426/// \brief Member lookup function that determines whether a given C++ 2427/// method overrides a method in a base class, to be used with 2428/// CXXRecordDecl::lookupInBases(). 2429static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2430 CXXBasePath &Path, 2431 void *UserData) { 2432 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2433 2434 FindOverriddenMethodData *Data 2435 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2436 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2437 Path.Decls.first != Path.Decls.second; 2438 ++Path.Decls.first) { 2439 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2440 OverloadedFunctionDecl::function_iterator MatchedDecl; 2441 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2442 return true; 2443 } 2444 } 2445 2446 return false; 2447} 2448 2449NamedDecl* 2450Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2451 QualType R, DeclaratorInfo *DInfo, 2452 NamedDecl* PrevDecl, 2453 MultiTemplateParamsArg TemplateParamLists, 2454 bool IsFunctionDefinition, bool &Redeclaration) { 2455 assert(R.getTypePtr()->isFunctionType()); 2456 2457 DeclarationName Name = GetNameForDeclarator(D); 2458 FunctionDecl::StorageClass SC = FunctionDecl::None; 2459 switch (D.getDeclSpec().getStorageClassSpec()) { 2460 default: assert(0 && "Unknown storage class!"); 2461 case DeclSpec::SCS_auto: 2462 case DeclSpec::SCS_register: 2463 case DeclSpec::SCS_mutable: 2464 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2465 diag::err_typecheck_sclass_func); 2466 D.setInvalidType(); 2467 break; 2468 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2469 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2470 case DeclSpec::SCS_static: { 2471 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2472 // C99 6.7.1p5: 2473 // The declaration of an identifier for a function that has 2474 // block scope shall have no explicit storage-class specifier 2475 // other than extern 2476 // See also (C++ [dcl.stc]p4). 2477 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2478 diag::err_static_block_func); 2479 SC = FunctionDecl::None; 2480 } else 2481 SC = FunctionDecl::Static; 2482 break; 2483 } 2484 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2485 } 2486 2487 if (D.getDeclSpec().isThreadSpecified()) 2488 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2489 2490 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2491 bool isInline = D.getDeclSpec().isInlineSpecified(); 2492 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2493 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2494 2495 // Check that the return type is not an abstract class type. 2496 // For record types, this is done by the AbstractClassUsageDiagnoser once 2497 // the class has been completely parsed. 2498 if (!DC->isRecord() && 2499 RequireNonAbstractType(D.getIdentifierLoc(), 2500 R->getAs<FunctionType>()->getResultType(), 2501 diag::err_abstract_type_in_decl, 2502 AbstractReturnType)) 2503 D.setInvalidType(); 2504 2505 // Do not allow returning a objc interface by-value. 2506 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2507 Diag(D.getIdentifierLoc(), 2508 diag::err_object_cannot_be_passed_returned_by_value) << 0 2509 << R->getAs<FunctionType>()->getResultType(); 2510 D.setInvalidType(); 2511 } 2512 2513 bool isVirtualOkay = false; 2514 FunctionDecl *NewFD; 2515 2516 if (isFriend) { 2517 // DC is the namespace in which the function is being declared. 2518 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2519 "friend function being created in a non-namespace context"); 2520 2521 // C++ [class.friend]p5 2522 // A function can be defined in a friend declaration of a 2523 // class . . . . Such a function is implicitly inline. 2524 isInline |= IsFunctionDefinition; 2525 } 2526 2527 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2528 // This is a C++ constructor declaration. 2529 assert(DC->isRecord() && 2530 "Constructors can only be declared in a member context"); 2531 2532 R = CheckConstructorDeclarator(D, R, SC); 2533 2534 // Create the new declaration 2535 NewFD = CXXConstructorDecl::Create(Context, 2536 cast<CXXRecordDecl>(DC), 2537 D.getIdentifierLoc(), Name, R, DInfo, 2538 isExplicit, isInline, 2539 /*isImplicitlyDeclared=*/false); 2540 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2541 // This is a C++ destructor declaration. 2542 if (DC->isRecord()) { 2543 R = CheckDestructorDeclarator(D, SC); 2544 2545 NewFD = CXXDestructorDecl::Create(Context, 2546 cast<CXXRecordDecl>(DC), 2547 D.getIdentifierLoc(), Name, R, 2548 isInline, 2549 /*isImplicitlyDeclared=*/false); 2550 2551 isVirtualOkay = true; 2552 } else { 2553 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2554 2555 // Create a FunctionDecl to satisfy the function definition parsing 2556 // code path. 2557 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2558 Name, R, DInfo, SC, isInline, 2559 /*hasPrototype=*/true); 2560 D.setInvalidType(); 2561 } 2562 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2563 if (!DC->isRecord()) { 2564 Diag(D.getIdentifierLoc(), 2565 diag::err_conv_function_not_member); 2566 return 0; 2567 } 2568 2569 CheckConversionDeclarator(D, R, SC); 2570 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2571 D.getIdentifierLoc(), Name, R, DInfo, 2572 isInline, isExplicit); 2573 2574 isVirtualOkay = true; 2575 } else if (DC->isRecord()) { 2576 // If the of the function is the same as the name of the record, then this 2577 // must be an invalid constructor that has a return type. 2578 // (The parser checks for a return type and makes the declarator a 2579 // constructor if it has no return type). 2580 // must have an invalid constructor that has a return type 2581 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2582 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2583 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2584 << SourceRange(D.getIdentifierLoc()); 2585 return 0; 2586 } 2587 2588 // This is a C++ method declaration. 2589 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2590 D.getIdentifierLoc(), Name, R, DInfo, 2591 (SC == FunctionDecl::Static), isInline); 2592 2593 isVirtualOkay = (SC != FunctionDecl::Static); 2594 } else { 2595 // Determine whether the function was written with a 2596 // prototype. This true when: 2597 // - we're in C++ (where every function has a prototype), 2598 // - there is a prototype in the declarator, or 2599 // - the type R of the function is some kind of typedef or other reference 2600 // to a type name (which eventually refers to a function type). 2601 bool HasPrototype = 2602 getLangOptions().CPlusPlus || 2603 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2604 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2605 2606 NewFD = FunctionDecl::Create(Context, DC, 2607 D.getIdentifierLoc(), 2608 Name, R, DInfo, SC, isInline, HasPrototype); 2609 } 2610 2611 if (D.isInvalidType()) 2612 NewFD->setInvalidDecl(); 2613 2614 // Set the lexical context. If the declarator has a C++ 2615 // scope specifier, or is the object of a friend declaration, the 2616 // lexical context will be different from the semantic context. 2617 NewFD->setLexicalDeclContext(CurContext); 2618 2619 // Match up the template parameter lists with the scope specifier, then 2620 // determine whether we have a template or a template specialization. 2621 FunctionTemplateDecl *FunctionTemplate = 0; 2622 bool isExplicitSpecialization = false; 2623 bool isFunctionTemplateSpecialization = false; 2624 if (TemplateParameterList *TemplateParams 2625 = MatchTemplateParametersToScopeSpecifier( 2626 D.getDeclSpec().getSourceRange().getBegin(), 2627 D.getCXXScopeSpec(), 2628 (TemplateParameterList**)TemplateParamLists.get(), 2629 TemplateParamLists.size(), 2630 isExplicitSpecialization)) { 2631 if (TemplateParams->size() > 0) { 2632 // This is a function template 2633 2634 // Check that we can declare a template here. 2635 if (CheckTemplateDeclScope(S, TemplateParams)) 2636 return 0; 2637 2638 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2639 NewFD->getLocation(), 2640 Name, TemplateParams, 2641 NewFD); 2642 FunctionTemplate->setLexicalDeclContext(CurContext); 2643 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2644 } else { 2645 // This is a function template specialization. 2646 isFunctionTemplateSpecialization = true; 2647 } 2648 2649 // FIXME: Free this memory properly. 2650 TemplateParamLists.release(); 2651 } 2652 2653 // C++ [dcl.fct.spec]p5: 2654 // The virtual specifier shall only be used in declarations of 2655 // nonstatic class member functions that appear within a 2656 // member-specification of a class declaration; see 10.3. 2657 // 2658 if (isVirtual && !NewFD->isInvalidDecl()) { 2659 if (!isVirtualOkay) { 2660 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2661 diag::err_virtual_non_function); 2662 } else if (!CurContext->isRecord()) { 2663 // 'virtual' was specified outside of the class. 2664 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2665 << CodeModificationHint::CreateRemoval( 2666 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2667 } else { 2668 // Okay: Add virtual to the method. 2669 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2670 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2671 CurClass->setAggregate(false); 2672 CurClass->setPOD(false); 2673 CurClass->setEmpty(false); 2674 CurClass->setPolymorphic(true); 2675 CurClass->setHasTrivialConstructor(false); 2676 CurClass->setHasTrivialCopyConstructor(false); 2677 CurClass->setHasTrivialCopyAssignment(false); 2678 } 2679 } 2680 2681 if (isFriend) { 2682 if (FunctionTemplate) { 2683 FunctionTemplate->setObjectOfFriendDecl( 2684 /* PreviouslyDeclared= */ PrevDecl != NULL); 2685 FunctionTemplate->setAccess(AS_public); 2686 } 2687 else 2688 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2689 2690 NewFD->setAccess(AS_public); 2691 } 2692 2693 2694 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2695 // Look for virtual methods in base classes that this method might override. 2696 CXXBasePaths Paths; 2697 FindOverriddenMethodData Data; 2698 Data.Method = NewMD; 2699 Data.S = this; 2700 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2701 Paths)) { 2702 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2703 E = Paths.found_decls_end(); I != E; ++I) { 2704 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2705 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2706 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2707 NewMD->addOverriddenMethod(OldMD); 2708 } 2709 } 2710 } 2711 } 2712 2713 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2714 !CurContext->isRecord()) { 2715 // C++ [class.static]p1: 2716 // A data or function member of a class may be declared static 2717 // in a class definition, in which case it is a static member of 2718 // the class. 2719 2720 // Complain about the 'static' specifier if it's on an out-of-line 2721 // member function definition. 2722 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2723 diag::err_static_out_of_line) 2724 << CodeModificationHint::CreateRemoval( 2725 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2726 } 2727 2728 // Handle GNU asm-label extension (encoded as an attribute). 2729 if (Expr *E = (Expr*) D.getAsmLabel()) { 2730 // The parser guarantees this is a string. 2731 StringLiteral *SE = cast<StringLiteral>(E); 2732 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2733 SE->getByteLength()))); 2734 } 2735 2736 // Copy the parameter declarations from the declarator D to the function 2737 // declaration NewFD, if they are available. First scavenge them into Params. 2738 llvm::SmallVector<ParmVarDecl*, 16> Params; 2739 if (D.getNumTypeObjects() > 0) { 2740 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2741 2742 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2743 // function that takes no arguments, not a function that takes a 2744 // single void argument. 2745 // We let through "const void" here because Sema::GetTypeForDeclarator 2746 // already checks for that case. 2747 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2748 FTI.ArgInfo[0].Param && 2749 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2750 // Empty arg list, don't push any params. 2751 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2752 2753 // In C++, the empty parameter-type-list must be spelled "void"; a 2754 // typedef of void is not permitted. 2755 if (getLangOptions().CPlusPlus && 2756 Param->getType().getUnqualifiedType() != Context.VoidTy) 2757 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2758 // FIXME: Leaks decl? 2759 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2760 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2761 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2762 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2763 Param->setDeclContext(NewFD); 2764 Params.push_back(Param); 2765 } 2766 } 2767 2768 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2769 // When we're declaring a function with a typedef, typeof, etc as in the 2770 // following example, we'll need to synthesize (unnamed) 2771 // parameters for use in the declaration. 2772 // 2773 // @code 2774 // typedef void fn(int); 2775 // fn f; 2776 // @endcode 2777 2778 // Synthesize a parameter for each argument type. 2779 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2780 AE = FT->arg_type_end(); AI != AE; ++AI) { 2781 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2782 SourceLocation(), 0, 2783 *AI, /*DInfo=*/0, 2784 VarDecl::None, 0); 2785 Param->setImplicit(); 2786 Params.push_back(Param); 2787 } 2788 } else { 2789 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2790 "Should not need args for typedef of non-prototype fn"); 2791 } 2792 // Finally, we know we have the right number of parameters, install them. 2793 NewFD->setParams(Context, Params.data(), Params.size()); 2794 2795 // If name lookup finds a previous declaration that is not in the 2796 // same scope as the new declaration, this may still be an 2797 // acceptable redeclaration. 2798 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2799 !(NewFD->hasLinkage() && 2800 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2801 PrevDecl = 0; 2802 2803 // If the declarator is a template-id, translate the parser's template 2804 // argument list into our AST format. 2805 bool HasExplicitTemplateArgs = false; 2806 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 2807 SourceLocation LAngleLoc, RAngleLoc; 2808 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2809 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2810 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2811 TemplateId->getTemplateArgs(), 2812 TemplateId->getTemplateArgIsType(), 2813 TemplateId->NumArgs); 2814 translateTemplateArguments(TemplateArgsPtr, 2815 TemplateId->getTemplateArgLocations(), 2816 TemplateArgs); 2817 TemplateArgsPtr.release(); 2818 2819 HasExplicitTemplateArgs = true; 2820 LAngleLoc = TemplateId->LAngleLoc; 2821 RAngleLoc = TemplateId->RAngleLoc; 2822 2823 if (FunctionTemplate) { 2824 // FIXME: Diagnose function template with explicit template 2825 // arguments. 2826 HasExplicitTemplateArgs = false; 2827 } else if (!isFunctionTemplateSpecialization && 2828 !D.getDeclSpec().isFriendSpecified()) { 2829 // We have encountered something that the user meant to be a 2830 // specialization (because it has explicitly-specified template 2831 // arguments) but that was not introduced with a "template<>" (or had 2832 // too few of them). 2833 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2834 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2835 << CodeModificationHint::CreateInsertion( 2836 D.getDeclSpec().getSourceRange().getBegin(), 2837 "template<> "); 2838 isFunctionTemplateSpecialization = true; 2839 } 2840 } 2841 2842 if (isFunctionTemplateSpecialization) { 2843 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2844 LAngleLoc, TemplateArgs.data(), 2845 TemplateArgs.size(), RAngleLoc, 2846 PrevDecl)) 2847 NewFD->setInvalidDecl(); 2848 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2849 CheckMemberSpecialization(NewFD, PrevDecl)) 2850 NewFD->setInvalidDecl(); 2851 2852 // Perform semantic checking on the function declaration. 2853 bool OverloadableAttrRequired = false; // FIXME: HACK! 2854 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2855 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2856 2857 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2858 // An out-of-line member function declaration must also be a 2859 // definition (C++ [dcl.meaning]p1). 2860 // Note that this is not the case for explicit specializations of 2861 // function templates or member functions of class templates, per 2862 // C++ [temp.expl.spec]p2. 2863 if (!IsFunctionDefinition && !isFriend && 2864 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2865 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2866 << D.getCXXScopeSpec().getRange(); 2867 NewFD->setInvalidDecl(); 2868 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2869 // The user tried to provide an out-of-line definition for a 2870 // function that is a member of a class or namespace, but there 2871 // was no such member function declared (C++ [class.mfct]p2, 2872 // C++ [namespace.memdef]p2). For example: 2873 // 2874 // class X { 2875 // void f() const; 2876 // }; 2877 // 2878 // void X::f() { } // ill-formed 2879 // 2880 // Complain about this problem, and attempt to suggest close 2881 // matches (e.g., those that differ only in cv-qualifiers and 2882 // whether the parameter types are references). 2883 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2884 << Name << DC << D.getCXXScopeSpec().getRange(); 2885 NewFD->setInvalidDecl(); 2886 2887 LookupResult Prev; 2888 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2889 assert(!Prev.isAmbiguous() && 2890 "Cannot have an ambiguity in previous-declaration lookup"); 2891 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2892 Func != FuncEnd; ++Func) { 2893 if (isa<FunctionDecl>(*Func) && 2894 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2895 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2896 } 2897 2898 PrevDecl = 0; 2899 } 2900 } 2901 2902 // Handle attributes. We need to have merged decls when handling attributes 2903 // (for example to check for conflicts, etc). 2904 // FIXME: This needs to happen before we merge declarations. Then, 2905 // let attribute merging cope with attribute conflicts. 2906 ProcessDeclAttributes(S, NewFD, D); 2907 2908 // attributes declared post-definition are currently ignored 2909 if (Redeclaration && PrevDecl) { 2910 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2911 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2912 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2913 Diag(Def->getLocation(), diag::note_previous_definition); 2914 } 2915 } 2916 2917 AddKnownFunctionAttributes(NewFD); 2918 2919 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2920 // If a function name is overloadable in C, then every function 2921 // with that name must be marked "overloadable". 2922 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2923 << Redeclaration << NewFD; 2924 if (PrevDecl) 2925 Diag(PrevDecl->getLocation(), 2926 diag::note_attribute_overloadable_prev_overload); 2927 NewFD->addAttr(::new (Context) OverloadableAttr()); 2928 } 2929 2930 // If this is a locally-scoped extern C function, update the 2931 // map of such names. 2932 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2933 && !NewFD->isInvalidDecl()) 2934 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2935 2936 // Set this FunctionDecl's range up to the right paren. 2937 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2938 2939 if (FunctionTemplate && NewFD->isInvalidDecl()) 2940 FunctionTemplate->setInvalidDecl(); 2941 2942 if (FunctionTemplate) 2943 return FunctionTemplate; 2944 2945 return NewFD; 2946} 2947 2948/// \brief Perform semantic checking of a new function declaration. 2949/// 2950/// Performs semantic analysis of the new function declaration 2951/// NewFD. This routine performs all semantic checking that does not 2952/// require the actual declarator involved in the declaration, and is 2953/// used both for the declaration of functions as they are parsed 2954/// (called via ActOnDeclarator) and for the declaration of functions 2955/// that have been instantiated via C++ template instantiation (called 2956/// via InstantiateDecl). 2957/// 2958/// \param IsExplicitSpecialiation whether this new function declaration is 2959/// an explicit specialization of the previous declaration. 2960/// 2961/// This sets NewFD->isInvalidDecl() to true if there was an error. 2962void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2963 bool IsExplicitSpecialization, 2964 bool &Redeclaration, 2965 bool &OverloadableAttrRequired) { 2966 // If NewFD is already known erroneous, don't do any of this checking. 2967 if (NewFD->isInvalidDecl()) 2968 return; 2969 2970 if (NewFD->getResultType()->isVariablyModifiedType()) { 2971 // Functions returning a variably modified type violate C99 6.7.5.2p2 2972 // because all functions have linkage. 2973 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2974 return NewFD->setInvalidDecl(); 2975 } 2976 2977 if (NewFD->isMain()) 2978 CheckMain(NewFD); 2979 2980 // Check for a previous declaration of this name. 2981 if (!PrevDecl && NewFD->isExternC()) { 2982 // Since we did not find anything by this name and we're declaring 2983 // an extern "C" function, look for a non-visible extern "C" 2984 // declaration with the same name. 2985 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2986 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2987 if (Pos != LocallyScopedExternalDecls.end()) 2988 PrevDecl = Pos->second; 2989 } 2990 2991 // Merge or overload the declaration with an existing declaration of 2992 // the same name, if appropriate. 2993 if (PrevDecl) { 2994 // Determine whether NewFD is an overload of PrevDecl or 2995 // a declaration that requires merging. If it's an overload, 2996 // there's no more work to do here; we'll just add the new 2997 // function to the scope. 2998 OverloadedFunctionDecl::function_iterator MatchedDecl; 2999 3000 if (!getLangOptions().CPlusPlus && 3001 AllowOverloadingOfFunction(PrevDecl, Context)) { 3002 OverloadableAttrRequired = true; 3003 3004 // Functions marked "overloadable" must have a prototype (that 3005 // we can't get through declaration merging). 3006 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3007 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3008 << NewFD; 3009 Redeclaration = true; 3010 3011 // Turn this into a variadic function with no parameters. 3012 QualType R = Context.getFunctionType( 3013 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3014 0, 0, true, 0); 3015 NewFD->setType(R); 3016 return NewFD->setInvalidDecl(); 3017 } 3018 } 3019 3020 if (PrevDecl && 3021 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3022 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3023 Redeclaration = true; 3024 Decl *OldDecl = PrevDecl; 3025 3026 // If PrevDecl was an overloaded function, extract the 3027 // FunctionDecl that matched. 3028 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3029 OldDecl = *MatchedDecl; 3030 3031 // NewFD and OldDecl represent declarations that need to be 3032 // merged. 3033 if (MergeFunctionDecl(NewFD, OldDecl)) 3034 return NewFD->setInvalidDecl(); 3035 3036 if (FunctionTemplateDecl *OldTemplateDecl 3037 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3038 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3039 FunctionTemplateDecl *NewTemplateDecl 3040 = NewFD->getDescribedFunctionTemplate(); 3041 assert(NewTemplateDecl && "Template/non-template mismatch"); 3042 if (CXXMethodDecl *Method 3043 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3044 Method->setAccess(OldTemplateDecl->getAccess()); 3045 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3046 } 3047 3048 // If this is an explicit specialization of a member that is a function 3049 // template, mark it as a member specialization. 3050 if (IsExplicitSpecialization && 3051 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3052 NewTemplateDecl->setMemberSpecialization(); 3053 assert(OldTemplateDecl->isMemberSpecialization()); 3054 } 3055 } else { 3056 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3057 NewFD->setAccess(OldDecl->getAccess()); 3058 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3059 } 3060 } 3061 } 3062 3063 // Semantic checking for this function declaration (in isolation). 3064 if (getLangOptions().CPlusPlus) { 3065 // C++-specific checks. 3066 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3067 CheckConstructor(Constructor); 3068 } else if (isa<CXXDestructorDecl>(NewFD)) { 3069 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3070 QualType ClassType = Context.getTypeDeclType(Record); 3071 if (!ClassType->isDependentType()) { 3072 DeclarationName Name 3073 = Context.DeclarationNames.getCXXDestructorName( 3074 Context.getCanonicalType(ClassType)); 3075 if (NewFD->getDeclName() != Name) { 3076 Diag(NewFD->getLocation(), diag::err_destructor_name); 3077 return NewFD->setInvalidDecl(); 3078 } 3079 } 3080 Record->setUserDeclaredDestructor(true); 3081 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3082 // user-defined destructor. 3083 Record->setPOD(false); 3084 3085 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3086 // declared destructor. 3087 // FIXME: C++0x: don't do this for "= default" destructors 3088 Record->setHasTrivialDestructor(false); 3089 } else if (CXXConversionDecl *Conversion 3090 = dyn_cast<CXXConversionDecl>(NewFD)) 3091 ActOnConversionDeclarator(Conversion); 3092 3093 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3094 if (NewFD->isOverloadedOperator() && 3095 CheckOverloadedOperatorDeclaration(NewFD)) 3096 return NewFD->setInvalidDecl(); 3097 3098 // In C++, check default arguments now that we have merged decls. Unless 3099 // the lexical context is the class, because in this case this is done 3100 // during delayed parsing anyway. 3101 if (!CurContext->isRecord()) 3102 CheckCXXDefaultArguments(NewFD); 3103 } 3104} 3105 3106void Sema::CheckMain(FunctionDecl* FD) { 3107 // C++ [basic.start.main]p3: A program that declares main to be inline 3108 // or static is ill-formed. 3109 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3110 // shall not appear in a declaration of main. 3111 // static main is not an error under C99, but we should warn about it. 3112 bool isInline = FD->isInlineSpecified(); 3113 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3114 if (isInline || isStatic) { 3115 unsigned diagID = diag::warn_unusual_main_decl; 3116 if (isInline || getLangOptions().CPlusPlus) 3117 diagID = diag::err_unusual_main_decl; 3118 3119 int which = isStatic + (isInline << 1) - 1; 3120 Diag(FD->getLocation(), diagID) << which; 3121 } 3122 3123 QualType T = FD->getType(); 3124 assert(T->isFunctionType() && "function decl is not of function type"); 3125 const FunctionType* FT = T->getAs<FunctionType>(); 3126 3127 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3128 // TODO: add a replacement fixit to turn the return type into 'int'. 3129 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3130 FD->setInvalidDecl(true); 3131 } 3132 3133 // Treat protoless main() as nullary. 3134 if (isa<FunctionNoProtoType>(FT)) return; 3135 3136 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3137 unsigned nparams = FTP->getNumArgs(); 3138 assert(FD->getNumParams() == nparams); 3139 3140 if (nparams > 3) { 3141 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3142 FD->setInvalidDecl(true); 3143 nparams = 3; 3144 } 3145 3146 // FIXME: a lot of the following diagnostics would be improved 3147 // if we had some location information about types. 3148 3149 QualType CharPP = 3150 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3151 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3152 3153 for (unsigned i = 0; i < nparams; ++i) { 3154 QualType AT = FTP->getArgType(i); 3155 3156 bool mismatch = true; 3157 3158 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3159 mismatch = false; 3160 else if (Expected[i] == CharPP) { 3161 // As an extension, the following forms are okay: 3162 // char const ** 3163 // char const * const * 3164 // char * const * 3165 3166 QualifierCollector qs; 3167 const PointerType* PT; 3168 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3169 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3170 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3171 qs.removeConst(); 3172 mismatch = !qs.empty(); 3173 } 3174 } 3175 3176 if (mismatch) { 3177 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3178 // TODO: suggest replacing given type with expected type 3179 FD->setInvalidDecl(true); 3180 } 3181 } 3182 3183 if (nparams == 1 && !FD->isInvalidDecl()) { 3184 Diag(FD->getLocation(), diag::warn_main_one_arg); 3185 } 3186} 3187 3188bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3189 // FIXME: Need strict checking. In C89, we need to check for 3190 // any assignment, increment, decrement, function-calls, or 3191 // commas outside of a sizeof. In C99, it's the same list, 3192 // except that the aforementioned are allowed in unevaluated 3193 // expressions. Everything else falls under the 3194 // "may accept other forms of constant expressions" exception. 3195 // (We never end up here for C++, so the constant expression 3196 // rules there don't matter.) 3197 if (Init->isConstantInitializer(Context)) 3198 return false; 3199 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3200 << Init->getSourceRange(); 3201 return true; 3202} 3203 3204void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3205 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3206} 3207 3208/// AddInitializerToDecl - Adds the initializer Init to the 3209/// declaration dcl. If DirectInit is true, this is C++ direct 3210/// initialization rather than copy initialization. 3211void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3212 Decl *RealDecl = dcl.getAs<Decl>(); 3213 // If there is no declaration, there was an error parsing it. Just ignore 3214 // the initializer. 3215 if (RealDecl == 0) 3216 return; 3217 3218 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3219 // With declarators parsed the way they are, the parser cannot 3220 // distinguish between a normal initializer and a pure-specifier. 3221 // Thus this grotesque test. 3222 IntegerLiteral *IL; 3223 Expr *Init = static_cast<Expr *>(init.get()); 3224 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3225 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3226 if (Method->isVirtualAsWritten()) { 3227 Method->setPure(); 3228 3229 // A class is abstract if at least one function is pure virtual. 3230 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3231 } else if (!Method->isInvalidDecl()) { 3232 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3233 << Method->getDeclName() << Init->getSourceRange(); 3234 Method->setInvalidDecl(); 3235 } 3236 } else { 3237 Diag(Method->getLocation(), diag::err_member_function_initialization) 3238 << Method->getDeclName() << Init->getSourceRange(); 3239 Method->setInvalidDecl(); 3240 } 3241 return; 3242 } 3243 3244 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3245 if (!VDecl) { 3246 if (getLangOptions().CPlusPlus && 3247 RealDecl->getLexicalDeclContext()->isRecord() && 3248 isa<NamedDecl>(RealDecl)) 3249 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3250 << cast<NamedDecl>(RealDecl)->getDeclName(); 3251 else 3252 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3253 RealDecl->setInvalidDecl(); 3254 return; 3255 } 3256 3257 if (!VDecl->getType()->isArrayType() && 3258 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3259 diag::err_typecheck_decl_incomplete_type)) { 3260 RealDecl->setInvalidDecl(); 3261 return; 3262 } 3263 3264 const VarDecl *Def = 0; 3265 if (VDecl->getDefinition(Def)) { 3266 Diag(VDecl->getLocation(), diag::err_redefinition) 3267 << VDecl->getDeclName(); 3268 Diag(Def->getLocation(), diag::note_previous_definition); 3269 VDecl->setInvalidDecl(); 3270 return; 3271 } 3272 3273 // Take ownership of the expression, now that we're sure we have somewhere 3274 // to put it. 3275 Expr *Init = init.takeAs<Expr>(); 3276 assert(Init && "missing initializer"); 3277 3278 // Get the decls type and save a reference for later, since 3279 // CheckInitializerTypes may change it. 3280 QualType DclT = VDecl->getType(), SavT = DclT; 3281 if (VDecl->isBlockVarDecl()) { 3282 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3283 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3284 VDecl->setInvalidDecl(); 3285 } else if (!VDecl->isInvalidDecl()) { 3286 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3287 VDecl->getDeclName(), DirectInit)) 3288 VDecl->setInvalidDecl(); 3289 3290 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3291 // Don't check invalid declarations to avoid emitting useless diagnostics. 3292 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3293 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3294 CheckForConstantInitializer(Init, DclT); 3295 } 3296 } 3297 } else if (VDecl->isStaticDataMember() && 3298 VDecl->getLexicalDeclContext()->isRecord()) { 3299 // This is an in-class initialization for a static data member, e.g., 3300 // 3301 // struct S { 3302 // static const int value = 17; 3303 // }; 3304 3305 // Attach the initializer 3306 VDecl->setInit(Context, Init); 3307 3308 // C++ [class.mem]p4: 3309 // A member-declarator can contain a constant-initializer only 3310 // if it declares a static member (9.4) of const integral or 3311 // const enumeration type, see 9.4.2. 3312 QualType T = VDecl->getType(); 3313 if (!T->isDependentType() && 3314 (!Context.getCanonicalType(T).isConstQualified() || 3315 !T->isIntegralType())) { 3316 Diag(VDecl->getLocation(), diag::err_member_initialization) 3317 << VDecl->getDeclName() << Init->getSourceRange(); 3318 VDecl->setInvalidDecl(); 3319 } else { 3320 // C++ [class.static.data]p4: 3321 // If a static data member is of const integral or const 3322 // enumeration type, its declaration in the class definition 3323 // can specify a constant-initializer which shall be an 3324 // integral constant expression (5.19). 3325 if (!Init->isTypeDependent() && 3326 !Init->getType()->isIntegralType()) { 3327 // We have a non-dependent, non-integral or enumeration type. 3328 Diag(Init->getSourceRange().getBegin(), 3329 diag::err_in_class_initializer_non_integral_type) 3330 << Init->getType() << Init->getSourceRange(); 3331 VDecl->setInvalidDecl(); 3332 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3333 // Check whether the expression is a constant expression. 3334 llvm::APSInt Value; 3335 SourceLocation Loc; 3336 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3337 Diag(Loc, diag::err_in_class_initializer_non_constant) 3338 << Init->getSourceRange(); 3339 VDecl->setInvalidDecl(); 3340 } else if (!VDecl->getType()->isDependentType()) 3341 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3342 } 3343 } 3344 } else if (VDecl->isFileVarDecl()) { 3345 if (VDecl->getStorageClass() == VarDecl::Extern) 3346 Diag(VDecl->getLocation(), diag::warn_extern_init); 3347 if (!VDecl->isInvalidDecl()) 3348 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3349 VDecl->getDeclName(), DirectInit)) 3350 VDecl->setInvalidDecl(); 3351 3352 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3353 // Don't check invalid declarations to avoid emitting useless diagnostics. 3354 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3355 // C99 6.7.8p4. All file scoped initializers need to be constant. 3356 CheckForConstantInitializer(Init, DclT); 3357 } 3358 } 3359 // If the type changed, it means we had an incomplete type that was 3360 // completed by the initializer. For example: 3361 // int ary[] = { 1, 3, 5 }; 3362 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3363 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3364 VDecl->setType(DclT); 3365 Init->setType(DclT); 3366 } 3367 3368 Init = MaybeCreateCXXExprWithTemporaries(Init, 3369 /*ShouldDestroyTemporaries=*/true); 3370 // Attach the initializer to the decl. 3371 VDecl->setInit(Context, Init); 3372 3373 // If the previous declaration of VDecl was a tentative definition, 3374 // remove it from the set of tentative definitions. 3375 if (VDecl->getPreviousDeclaration() && 3376 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3377 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3378 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3379 } 3380 3381 return; 3382} 3383 3384void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3385 bool TypeContainsUndeducedAuto) { 3386 Decl *RealDecl = dcl.getAs<Decl>(); 3387 3388 // If there is no declaration, there was an error parsing it. Just ignore it. 3389 if (RealDecl == 0) 3390 return; 3391 3392 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3393 QualType Type = Var->getType(); 3394 3395 // Record tentative definitions. 3396 if (Var->isTentativeDefinition(Context)) { 3397 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3398 InsertPair = 3399 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3400 3401 // Keep the latest definition in the map. If we see 'int i; int i;' we 3402 // want the second one in the map. 3403 InsertPair.first->second = Var; 3404 3405 // However, for the list, we don't care about the order, just make sure 3406 // that there are no dupes for a given declaration name. 3407 if (InsertPair.second) 3408 TentativeDefinitionList.push_back(Var->getDeclName()); 3409 } 3410 3411 // C++ [dcl.init.ref]p3: 3412 // The initializer can be omitted for a reference only in a 3413 // parameter declaration (8.3.5), in the declaration of a 3414 // function return type, in the declaration of a class member 3415 // within its class declaration (9.2), and where the extern 3416 // specifier is explicitly used. 3417 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3418 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3419 << Var->getDeclName() 3420 << SourceRange(Var->getLocation(), Var->getLocation()); 3421 Var->setInvalidDecl(); 3422 return; 3423 } 3424 3425 // C++0x [dcl.spec.auto]p3 3426 if (TypeContainsUndeducedAuto) { 3427 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3428 << Var->getDeclName() << Type; 3429 Var->setInvalidDecl(); 3430 return; 3431 } 3432 3433 // C++ [temp.expl.spec]p15: 3434 // An explicit specialization of a static data member of a template is a 3435 // definition if the declaration includes an initializer; otherwise, it 3436 // is a declaration. 3437 if (Var->isStaticDataMember() && 3438 Var->getInstantiatedFromStaticDataMember() && 3439 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3440 return; 3441 3442 // C++ [dcl.init]p9: 3443 // If no initializer is specified for an object, and the object 3444 // is of (possibly cv-qualified) non-POD class type (or array 3445 // thereof), the object shall be default-initialized; if the 3446 // object is of const-qualified type, the underlying class type 3447 // shall have a user-declared default constructor. 3448 // 3449 // FIXME: Diagnose the "user-declared default constructor" bit. 3450 if (getLangOptions().CPlusPlus) { 3451 QualType InitType = Type; 3452 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3453 InitType = Context.getBaseElementType(Array); 3454 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3455 InitType->isRecordType() && !InitType->isDependentType()) { 3456 if (!RequireCompleteType(Var->getLocation(), InitType, 3457 diag::err_invalid_incomplete_type_use)) { 3458 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3459 3460 CXXConstructorDecl *Constructor 3461 = PerformInitializationByConstructor(InitType, 3462 MultiExprArg(*this, 0, 0), 3463 Var->getLocation(), 3464 SourceRange(Var->getLocation(), 3465 Var->getLocation()), 3466 Var->getDeclName(), 3467 IK_Default, 3468 ConstructorArgs); 3469 3470 // FIXME: Location info for the variable initialization? 3471 if (!Constructor) 3472 Var->setInvalidDecl(); 3473 else { 3474 // FIXME: Cope with initialization of arrays 3475 if (!Constructor->isTrivial() && 3476 InitializeVarWithConstructor(Var, Constructor, 3477 move_arg(ConstructorArgs))) 3478 Var->setInvalidDecl(); 3479 3480 FinalizeVarWithDestructor(Var, InitType); 3481 } 3482 } else { 3483 Var->setInvalidDecl(); 3484 } 3485 } 3486 } 3487 3488#if 0 3489 // FIXME: Temporarily disabled because we are not properly parsing 3490 // linkage specifications on declarations, e.g., 3491 // 3492 // extern "C" const CGPoint CGPointerZero; 3493 // 3494 // C++ [dcl.init]p9: 3495 // 3496 // If no initializer is specified for an object, and the 3497 // object is of (possibly cv-qualified) non-POD class type (or 3498 // array thereof), the object shall be default-initialized; if 3499 // the object is of const-qualified type, the underlying class 3500 // type shall have a user-declared default 3501 // constructor. Otherwise, if no initializer is specified for 3502 // an object, the object and its subobjects, if any, have an 3503 // indeterminate initial value; if the object or any of its 3504 // subobjects are of const-qualified type, the program is 3505 // ill-formed. 3506 // 3507 // This isn't technically an error in C, so we don't diagnose it. 3508 // 3509 // FIXME: Actually perform the POD/user-defined default 3510 // constructor check. 3511 if (getLangOptions().CPlusPlus && 3512 Context.getCanonicalType(Type).isConstQualified() && 3513 !Var->hasExternalStorage()) 3514 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3515 << Var->getName() 3516 << SourceRange(Var->getLocation(), Var->getLocation()); 3517#endif 3518 } 3519} 3520 3521Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3522 DeclPtrTy *Group, 3523 unsigned NumDecls) { 3524 llvm::SmallVector<Decl*, 8> Decls; 3525 3526 if (DS.isTypeSpecOwned()) 3527 Decls.push_back((Decl*)DS.getTypeRep()); 3528 3529 for (unsigned i = 0; i != NumDecls; ++i) 3530 if (Decl *D = Group[i].getAs<Decl>()) 3531 Decls.push_back(D); 3532 3533 // Perform semantic analysis that depends on having fully processed both 3534 // the declarator and initializer. 3535 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3536 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3537 if (!IDecl) 3538 continue; 3539 QualType T = IDecl->getType(); 3540 3541 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3542 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3543 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3544 if (T->isDependentType()) { 3545 // If T is dependent, we should not require a complete type. 3546 // (RequireCompleteType shouldn't be called with dependent types.) 3547 // But we still can at least check if we've got an array of unspecified 3548 // size without an initializer. 3549 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3550 !IDecl->getInit()) { 3551 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3552 << T; 3553 IDecl->setInvalidDecl(); 3554 } 3555 } else if (!IDecl->isInvalidDecl()) { 3556 // If T is an incomplete array type with an initializer list that is 3557 // dependent on something, its size has not been fixed. We could attempt 3558 // to fix the size for such arrays, but we would still have to check 3559 // here for initializers containing a C++0x vararg expansion, e.g. 3560 // template <typename... Args> void f(Args... args) { 3561 // int vals[] = { args }; 3562 // } 3563 const IncompleteArrayType *IAT = T->getAs<IncompleteArrayType>(); 3564 Expr *Init = IDecl->getInit(); 3565 if (IAT && Init && 3566 (Init->isTypeDependent() || Init->isValueDependent())) { 3567 // Check that the member type of the array is complete, at least. 3568 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3569 diag::err_typecheck_decl_incomplete_type)) 3570 IDecl->setInvalidDecl(); 3571 } else if (RequireCompleteType(IDecl->getLocation(), T, 3572 diag::err_typecheck_decl_incomplete_type)) 3573 IDecl->setInvalidDecl(); 3574 } 3575 } 3576 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3577 // object that has file scope without an initializer, and without a 3578 // storage-class specifier or with the storage-class specifier "static", 3579 // constitutes a tentative definition. Note: A tentative definition with 3580 // external linkage is valid (C99 6.2.2p5). 3581 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3582 if (const IncompleteArrayType *ArrayT 3583 = Context.getAsIncompleteArrayType(T)) { 3584 if (RequireCompleteType(IDecl->getLocation(), 3585 ArrayT->getElementType(), 3586 diag::err_illegal_decl_array_incomplete_type)) 3587 IDecl->setInvalidDecl(); 3588 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3589 // C99 6.9.2p3: If the declaration of an identifier for an object is 3590 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3591 // declared type shall not be an incomplete type. 3592 // NOTE: code such as the following 3593 // static struct s; 3594 // struct s { int a; }; 3595 // is accepted by gcc. Hence here we issue a warning instead of 3596 // an error and we do not invalidate the static declaration. 3597 // NOTE: to avoid multiple warnings, only check the first declaration. 3598 if (IDecl->getPreviousDeclaration() == 0) 3599 RequireCompleteType(IDecl->getLocation(), T, 3600 diag::ext_typecheck_decl_incomplete_type); 3601 } 3602 } 3603 } 3604 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3605 Decls.data(), Decls.size())); 3606} 3607 3608 3609/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3610/// to introduce parameters into function prototype scope. 3611Sema::DeclPtrTy 3612Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3613 const DeclSpec &DS = D.getDeclSpec(); 3614 3615 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3616 VarDecl::StorageClass StorageClass = VarDecl::None; 3617 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3618 StorageClass = VarDecl::Register; 3619 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3620 Diag(DS.getStorageClassSpecLoc(), 3621 diag::err_invalid_storage_class_in_func_decl); 3622 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3623 } 3624 3625 if (D.getDeclSpec().isThreadSpecified()) 3626 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3627 3628 DiagnoseFunctionSpecifiers(D); 3629 3630 // Check that there are no default arguments inside the type of this 3631 // parameter (C++ only). 3632 if (getLangOptions().CPlusPlus) 3633 CheckExtraCXXDefaultArguments(D); 3634 3635 DeclaratorInfo *DInfo = 0; 3636 TagDecl *OwnedDecl = 0; 3637 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3638 3639 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3640 // C++ [dcl.fct]p6: 3641 // Types shall not be defined in return or parameter types. 3642 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3643 << Context.getTypeDeclType(OwnedDecl); 3644 } 3645 3646 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3647 // Can this happen for params? We already checked that they don't conflict 3648 // among each other. Here they can only shadow globals, which is ok. 3649 IdentifierInfo *II = D.getIdentifier(); 3650 if (II) { 3651 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3652 if (PrevDecl->isTemplateParameter()) { 3653 // Maybe we will complain about the shadowed template parameter. 3654 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3655 // Just pretend that we didn't see the previous declaration. 3656 PrevDecl = 0; 3657 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3658 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3659 3660 // Recover by removing the name 3661 II = 0; 3662 D.SetIdentifier(0, D.getIdentifierLoc()); 3663 } 3664 } 3665 } 3666 3667 // Parameters can not be abstract class types. 3668 // For record types, this is done by the AbstractClassUsageDiagnoser once 3669 // the class has been completely parsed. 3670 if (!CurContext->isRecord() && 3671 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3672 diag::err_abstract_type_in_decl, 3673 AbstractParamType)) 3674 D.setInvalidType(true); 3675 3676 QualType T = adjustParameterType(parmDeclType); 3677 3678 ParmVarDecl *New 3679 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3680 T, DInfo, StorageClass, 0); 3681 3682 if (D.isInvalidType()) 3683 New->setInvalidDecl(); 3684 3685 // Parameter declarators cannot be interface types. All ObjC objects are 3686 // passed by reference. 3687 if (T->isObjCInterfaceType()) { 3688 Diag(D.getIdentifierLoc(), 3689 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3690 New->setInvalidDecl(); 3691 } 3692 3693 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3694 if (D.getCXXScopeSpec().isSet()) { 3695 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3696 << D.getCXXScopeSpec().getRange(); 3697 New->setInvalidDecl(); 3698 } 3699 3700 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3701 // duration shall not be qualified by an address-space qualifier." 3702 // Since all parameters have automatic store duration, they can not have 3703 // an address space. 3704 if (T.getAddressSpace() != 0) { 3705 Diag(D.getIdentifierLoc(), 3706 diag::err_arg_with_address_space); 3707 New->setInvalidDecl(); 3708 } 3709 3710 3711 // Add the parameter declaration into this scope. 3712 S->AddDecl(DeclPtrTy::make(New)); 3713 if (II) 3714 IdResolver.AddDecl(New); 3715 3716 ProcessDeclAttributes(S, New, D); 3717 3718 if (New->hasAttr<BlocksAttr>()) { 3719 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3720 } 3721 return DeclPtrTy::make(New); 3722} 3723 3724void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3725 SourceLocation LocAfterDecls) { 3726 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3727 "Not a function declarator!"); 3728 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3729 3730 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3731 // for a K&R function. 3732 if (!FTI.hasPrototype) { 3733 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3734 --i; 3735 if (FTI.ArgInfo[i].Param == 0) { 3736 llvm::SmallString<256> Code; 3737 llvm::raw_svector_ostream(Code) << " int " 3738 << FTI.ArgInfo[i].Ident->getName() 3739 << ";\n"; 3740 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3741 << FTI.ArgInfo[i].Ident 3742 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3743 3744 // Implicitly declare the argument as type 'int' for lack of a better 3745 // type. 3746 DeclSpec DS; 3747 const char* PrevSpec; // unused 3748 unsigned DiagID; // unused 3749 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3750 PrevSpec, DiagID); 3751 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3752 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3753 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3754 } 3755 } 3756 } 3757} 3758 3759Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3760 Declarator &D) { 3761 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3762 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3763 "Not a function declarator!"); 3764 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3765 3766 if (FTI.hasPrototype) { 3767 // FIXME: Diagnose arguments without names in C. 3768 } 3769 3770 Scope *ParentScope = FnBodyScope->getParent(); 3771 3772 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3773 MultiTemplateParamsArg(*this), 3774 /*IsFunctionDefinition=*/true); 3775 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3776} 3777 3778Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3779 // Clear the last template instantiation error context. 3780 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 3781 3782 if (!D) 3783 return D; 3784 FunctionDecl *FD = 0; 3785 3786 if (FunctionTemplateDecl *FunTmpl 3787 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3788 FD = FunTmpl->getTemplatedDecl(); 3789 else 3790 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3791 3792 CurFunctionNeedsScopeChecking = false; 3793 3794 // See if this is a redefinition. 3795 const FunctionDecl *Definition; 3796 if (FD->getBody(Definition)) { 3797 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3798 Diag(Definition->getLocation(), diag::note_previous_definition); 3799 } 3800 3801 // Builtin functions cannot be defined. 3802 if (unsigned BuiltinID = FD->getBuiltinID()) { 3803 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3804 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3805 FD->setInvalidDecl(); 3806 } 3807 } 3808 3809 // The return type of a function definition must be complete 3810 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3811 QualType ResultType = FD->getResultType(); 3812 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3813 !FD->isInvalidDecl() && 3814 RequireCompleteType(FD->getLocation(), ResultType, 3815 diag::err_func_def_incomplete_result)) 3816 FD->setInvalidDecl(); 3817 3818 // GNU warning -Wmissing-prototypes: 3819 // Warn if a global function is defined without a previous 3820 // prototype declaration. This warning is issued even if the 3821 // definition itself provides a prototype. The aim is to detect 3822 // global functions that fail to be declared in header files. 3823 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3824 !FD->isMain()) { 3825 bool MissingPrototype = true; 3826 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3827 Prev; Prev = Prev->getPreviousDeclaration()) { 3828 // Ignore any declarations that occur in function or method 3829 // scope, because they aren't visible from the header. 3830 if (Prev->getDeclContext()->isFunctionOrMethod()) 3831 continue; 3832 3833 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3834 break; 3835 } 3836 3837 if (MissingPrototype) 3838 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3839 } 3840 3841 if (FnBodyScope) 3842 PushDeclContext(FnBodyScope, FD); 3843 3844 // Check the validity of our function parameters 3845 CheckParmsForFunctionDef(FD); 3846 3847 // Introduce our parameters into the function scope 3848 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3849 ParmVarDecl *Param = FD->getParamDecl(p); 3850 Param->setOwningFunction(FD); 3851 3852 // If this has an identifier, add it to the scope stack. 3853 if (Param->getIdentifier() && FnBodyScope) 3854 PushOnScopeChains(Param, FnBodyScope); 3855 } 3856 3857 // Checking attributes of current function definition 3858 // dllimport attribute. 3859 if (FD->getAttr<DLLImportAttr>() && 3860 (!FD->getAttr<DLLExportAttr>())) { 3861 // dllimport attribute cannot be applied to definition. 3862 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3863 Diag(FD->getLocation(), 3864 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3865 << "dllimport"; 3866 FD->setInvalidDecl(); 3867 return DeclPtrTy::make(FD); 3868 } else { 3869 // If a symbol previously declared dllimport is later defined, the 3870 // attribute is ignored in subsequent references, and a warning is 3871 // emitted. 3872 Diag(FD->getLocation(), 3873 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3874 << FD->getNameAsCString() << "dllimport"; 3875 } 3876 } 3877 return DeclPtrTy::make(FD); 3878} 3879 3880Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3881 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3882} 3883 3884Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3885 bool IsInstantiation) { 3886 Decl *dcl = D.getAs<Decl>(); 3887 Stmt *Body = BodyArg.takeAs<Stmt>(); 3888 3889 FunctionDecl *FD = 0; 3890 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3891 if (FunTmpl) 3892 FD = FunTmpl->getTemplatedDecl(); 3893 else 3894 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3895 3896 if (FD) { 3897 FD->setBody(Body); 3898 if (FD->isMain()) 3899 // C and C++ allow for main to automagically return 0. 3900 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3901 FD->setHasImplicitReturnZero(true); 3902 else 3903 CheckFallThroughForFunctionDef(FD, Body); 3904 3905 if (!FD->isInvalidDecl()) 3906 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3907 3908 // C++ [basic.def.odr]p2: 3909 // [...] A virtual member function is used if it is not pure. [...] 3910 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3911 if (Method->isVirtual() && !Method->isPure()) 3912 MarkDeclarationReferenced(Method->getLocation(), Method); 3913 3914 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3915 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3916 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3917 MD->setBody(Body); 3918 CheckFallThroughForFunctionDef(MD, Body); 3919 MD->setEndLoc(Body->getLocEnd()); 3920 3921 if (!MD->isInvalidDecl()) 3922 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3923 } else { 3924 Body->Destroy(Context); 3925 return DeclPtrTy(); 3926 } 3927 if (!IsInstantiation) 3928 PopDeclContext(); 3929 3930 // Verify and clean out per-function state. 3931 3932 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3933 3934 // Check goto/label use. 3935 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3936 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3937 LabelStmt *L = I->second; 3938 3939 // Verify that we have no forward references left. If so, there was a goto 3940 // or address of a label taken, but no definition of it. Label fwd 3941 // definitions are indicated with a null substmt. 3942 if (L->getSubStmt() != 0) 3943 continue; 3944 3945 // Emit error. 3946 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3947 3948 // At this point, we have gotos that use the bogus label. Stitch it into 3949 // the function body so that they aren't leaked and that the AST is well 3950 // formed. 3951 if (Body == 0) { 3952 // The whole function wasn't parsed correctly, just delete this. 3953 L->Destroy(Context); 3954 continue; 3955 } 3956 3957 // Otherwise, the body is valid: we want to stitch the label decl into the 3958 // function somewhere so that it is properly owned and so that the goto 3959 // has a valid target. Do this by creating a new compound stmt with the 3960 // label in it. 3961 3962 // Give the label a sub-statement. 3963 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3964 3965 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3966 cast<CXXTryStmt>(Body)->getTryBlock() : 3967 cast<CompoundStmt>(Body); 3968 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3969 Elements.push_back(L); 3970 Compound->setStmts(Context, &Elements[0], Elements.size()); 3971 } 3972 FunctionLabelMap.clear(); 3973 3974 if (!Body) return D; 3975 3976 // Verify that that gotos and switch cases don't jump into scopes illegally. 3977 if (CurFunctionNeedsScopeChecking) 3978 DiagnoseInvalidJumps(Body); 3979 3980 // C++ constructors that have function-try-blocks can't have return 3981 // statements in the handlers of that block. (C++ [except.handle]p14) 3982 // Verify this. 3983 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3984 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3985 3986 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3987 computeBaseOrMembersToDestroy(Destructor); 3988 return D; 3989} 3990 3991/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3992/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3993NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3994 IdentifierInfo &II, Scope *S) { 3995 // Before we produce a declaration for an implicitly defined 3996 // function, see whether there was a locally-scoped declaration of 3997 // this name as a function or variable. If so, use that 3998 // (non-visible) declaration, and complain about it. 3999 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4000 = LocallyScopedExternalDecls.find(&II); 4001 if (Pos != LocallyScopedExternalDecls.end()) { 4002 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4003 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4004 return Pos->second; 4005 } 4006 4007 // Extension in C99. Legal in C90, but warn about it. 4008 if (II.getName().startswith("__builtin_")) 4009 Diag(Loc, diag::warn_builtin_unknown) << &II; 4010 else if (getLangOptions().C99) 4011 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4012 else 4013 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4014 4015 // Set a Declarator for the implicit definition: int foo(); 4016 const char *Dummy; 4017 DeclSpec DS; 4018 unsigned DiagID; 4019 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4020 Error = Error; // Silence warning. 4021 assert(!Error && "Error setting up implicit decl!"); 4022 Declarator D(DS, Declarator::BlockContext); 4023 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4024 0, 0, false, SourceLocation(), 4025 false, 0,0,0, Loc, Loc, D), 4026 SourceLocation()); 4027 D.SetIdentifier(&II, Loc); 4028 4029 // Insert this function into translation-unit scope. 4030 4031 DeclContext *PrevDC = CurContext; 4032 CurContext = Context.getTranslationUnitDecl(); 4033 4034 FunctionDecl *FD = 4035 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4036 FD->setImplicit(); 4037 4038 CurContext = PrevDC; 4039 4040 AddKnownFunctionAttributes(FD); 4041 4042 return FD; 4043} 4044 4045/// \brief Adds any function attributes that we know a priori based on 4046/// the declaration of this function. 4047/// 4048/// These attributes can apply both to implicitly-declared builtins 4049/// (like __builtin___printf_chk) or to library-declared functions 4050/// like NSLog or printf. 4051void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4052 if (FD->isInvalidDecl()) 4053 return; 4054 4055 // If this is a built-in function, map its builtin attributes to 4056 // actual attributes. 4057 if (unsigned BuiltinID = FD->getBuiltinID()) { 4058 // Handle printf-formatting attributes. 4059 unsigned FormatIdx; 4060 bool HasVAListArg; 4061 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4062 if (!FD->getAttr<FormatAttr>()) 4063 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4064 HasVAListArg ? 0 : FormatIdx + 2)); 4065 } 4066 4067 // Mark const if we don't care about errno and that is the only 4068 // thing preventing the function from being const. This allows 4069 // IRgen to use LLVM intrinsics for such functions. 4070 if (!getLangOptions().MathErrno && 4071 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4072 if (!FD->getAttr<ConstAttr>()) 4073 FD->addAttr(::new (Context) ConstAttr()); 4074 } 4075 4076 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4077 FD->addAttr(::new (Context) NoReturnAttr()); 4078 } 4079 4080 IdentifierInfo *Name = FD->getIdentifier(); 4081 if (!Name) 4082 return; 4083 if ((!getLangOptions().CPlusPlus && 4084 FD->getDeclContext()->isTranslationUnit()) || 4085 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4086 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4087 LinkageSpecDecl::lang_c)) { 4088 // Okay: this could be a libc/libm/Objective-C function we know 4089 // about. 4090 } else 4091 return; 4092 4093 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4094 // FIXME: NSLog and NSLogv should be target specific 4095 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4096 // FIXME: We known better than our headers. 4097 const_cast<FormatAttr *>(Format)->setType("printf"); 4098 } else 4099 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4100 Name->isStr("NSLogv") ? 0 : 2)); 4101 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4102 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4103 // target-specific builtins, perhaps? 4104 if (!FD->getAttr<FormatAttr>()) 4105 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4106 Name->isStr("vasprintf") ? 0 : 3)); 4107 } 4108} 4109 4110TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4111 DeclaratorInfo *DInfo) { 4112 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4113 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4114 4115 if (!DInfo) { 4116 assert(D.isInvalidType() && "no declarator info for valid type"); 4117 DInfo = Context.getTrivialDeclaratorInfo(T); 4118 } 4119 4120 // Scope manipulation handled by caller. 4121 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4122 D.getIdentifierLoc(), 4123 D.getIdentifier(), 4124 DInfo); 4125 4126 if (const TagType *TT = T->getAs<TagType>()) { 4127 TagDecl *TD = TT->getDecl(); 4128 4129 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4130 // keep track of the TypedefDecl. 4131 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4132 TD->setTypedefForAnonDecl(NewTD); 4133 } 4134 4135 if (D.isInvalidType()) 4136 NewTD->setInvalidDecl(); 4137 return NewTD; 4138} 4139 4140 4141/// \brief Determine whether a tag with a given kind is acceptable 4142/// as a redeclaration of the given tag declaration. 4143/// 4144/// \returns true if the new tag kind is acceptable, false otherwise. 4145bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4146 TagDecl::TagKind NewTag, 4147 SourceLocation NewTagLoc, 4148 const IdentifierInfo &Name) { 4149 // C++ [dcl.type.elab]p3: 4150 // The class-key or enum keyword present in the 4151 // elaborated-type-specifier shall agree in kind with the 4152 // declaration to which the name in theelaborated-type-specifier 4153 // refers. This rule also applies to the form of 4154 // elaborated-type-specifier that declares a class-name or 4155 // friend class since it can be construed as referring to the 4156 // definition of the class. Thus, in any 4157 // elaborated-type-specifier, the enum keyword shall be used to 4158 // refer to an enumeration (7.2), the union class-keyshall be 4159 // used to refer to a union (clause 9), and either the class or 4160 // struct class-key shall be used to refer to a class (clause 9) 4161 // declared using the class or struct class-key. 4162 TagDecl::TagKind OldTag = Previous->getTagKind(); 4163 if (OldTag == NewTag) 4164 return true; 4165 4166 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4167 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4168 // Warn about the struct/class tag mismatch. 4169 bool isTemplate = false; 4170 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4171 isTemplate = Record->getDescribedClassTemplate(); 4172 4173 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4174 << (NewTag == TagDecl::TK_class) 4175 << isTemplate << &Name 4176 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4177 OldTag == TagDecl::TK_class? "class" : "struct"); 4178 Diag(Previous->getLocation(), diag::note_previous_use); 4179 return true; 4180 } 4181 return false; 4182} 4183 4184/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4185/// former case, Name will be non-null. In the later case, Name will be null. 4186/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4187/// reference/declaration/definition of a tag. 4188Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4189 SourceLocation KWLoc, const CXXScopeSpec &SS, 4190 IdentifierInfo *Name, SourceLocation NameLoc, 4191 AttributeList *Attr, AccessSpecifier AS, 4192 MultiTemplateParamsArg TemplateParameterLists, 4193 bool &OwnedDecl, bool &IsDependent) { 4194 // If this is not a definition, it must have a name. 4195 assert((Name != 0 || TUK == TUK_Definition) && 4196 "Nameless record must be a definition!"); 4197 4198 OwnedDecl = false; 4199 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4200 4201 // FIXME: Check explicit specializations more carefully. 4202 bool isExplicitSpecialization = false; 4203 if (TUK != TUK_Reference) { 4204 if (TemplateParameterList *TemplateParams 4205 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4206 (TemplateParameterList**)TemplateParameterLists.get(), 4207 TemplateParameterLists.size(), 4208 isExplicitSpecialization)) { 4209 if (TemplateParams->size() > 0) { 4210 // This is a declaration or definition of a class template (which may 4211 // be a member of another template). 4212 OwnedDecl = false; 4213 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4214 SS, Name, NameLoc, Attr, 4215 TemplateParams, 4216 AS); 4217 TemplateParameterLists.release(); 4218 return Result.get(); 4219 } else { 4220 // The "template<>" header is extraneous. 4221 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4222 << ElaboratedType::getNameForTagKind(Kind) << Name; 4223 isExplicitSpecialization = true; 4224 } 4225 } 4226 4227 TemplateParameterLists.release(); 4228 } 4229 4230 DeclContext *SearchDC = CurContext; 4231 DeclContext *DC = CurContext; 4232 NamedDecl *PrevDecl = 0; 4233 bool isStdBadAlloc = false; 4234 bool Invalid = false; 4235 4236 bool RedeclarationOnly = (TUK != TUK_Reference); 4237 4238 if (Name && SS.isNotEmpty()) { 4239 // We have a nested-name tag ('struct foo::bar'). 4240 4241 // Check for invalid 'foo::'. 4242 if (SS.isInvalid()) { 4243 Name = 0; 4244 goto CreateNewDecl; 4245 } 4246 4247 // If this is a friend or a reference to a class in a dependent 4248 // context, don't try to make a decl for it. 4249 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4250 DC = computeDeclContext(SS, false); 4251 if (!DC) { 4252 IsDependent = true; 4253 return DeclPtrTy(); 4254 } 4255 } 4256 4257 if (RequireCompleteDeclContext(SS)) 4258 return DeclPtrTy::make((Decl *)0); 4259 4260 DC = computeDeclContext(SS, true); 4261 SearchDC = DC; 4262 // Look-up name inside 'foo::'. 4263 LookupResult R; 4264 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4265 4266 if (R.isAmbiguous()) { 4267 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4268 return DeclPtrTy(); 4269 } 4270 4271 if (R.getKind() == LookupResult::Found) 4272 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4273 4274 // A tag 'foo::bar' must already exist. 4275 if (!PrevDecl) { 4276 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4277 Name = 0; 4278 Invalid = true; 4279 goto CreateNewDecl; 4280 } 4281 } else if (Name) { 4282 // If this is a named struct, check to see if there was a previous forward 4283 // declaration or definition. 4284 // FIXME: We're looking into outer scopes here, even when we 4285 // shouldn't be. Doing so can result in ambiguities that we 4286 // shouldn't be diagnosing. 4287 LookupResult R; 4288 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4289 if (R.isAmbiguous()) { 4290 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4291 // FIXME: This is not best way to recover from case like: 4292 // 4293 // struct S s; 4294 // 4295 // causes needless "incomplete type" error later. 4296 Name = 0; 4297 PrevDecl = 0; 4298 Invalid = true; 4299 } else 4300 PrevDecl = R.getAsSingleDecl(Context); 4301 4302 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4303 // FIXME: This makes sure that we ignore the contexts associated 4304 // with C structs, unions, and enums when looking for a matching 4305 // tag declaration or definition. See the similar lookup tweak 4306 // in Sema::LookupName; is there a better way to deal with this? 4307 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4308 SearchDC = SearchDC->getParent(); 4309 } 4310 } 4311 4312 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4313 // Maybe we will complain about the shadowed template parameter. 4314 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4315 // Just pretend that we didn't see the previous declaration. 4316 PrevDecl = 0; 4317 } 4318 4319 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4320 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4321 // This is a declaration of or a reference to "std::bad_alloc". 4322 isStdBadAlloc = true; 4323 4324 if (!PrevDecl && StdBadAlloc) { 4325 // std::bad_alloc has been implicitly declared (but made invisible to 4326 // name lookup). Fill in this implicit declaration as the previous 4327 // declaration, so that the declarations get chained appropriately. 4328 PrevDecl = StdBadAlloc; 4329 } 4330 } 4331 4332 if (PrevDecl) { 4333 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4334 // If this is a use of a previous tag, or if the tag is already declared 4335 // in the same scope (so that the definition/declaration completes or 4336 // rementions the tag), reuse the decl. 4337 if (TUK == TUK_Reference || TUK == TUK_Friend || 4338 isDeclInScope(PrevDecl, SearchDC, S)) { 4339 // Make sure that this wasn't declared as an enum and now used as a 4340 // struct or something similar. 4341 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4342 bool SafeToContinue 4343 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4344 Kind != TagDecl::TK_enum); 4345 if (SafeToContinue) 4346 Diag(KWLoc, diag::err_use_with_wrong_tag) 4347 << Name 4348 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4349 PrevTagDecl->getKindName()); 4350 else 4351 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4352 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4353 4354 if (SafeToContinue) 4355 Kind = PrevTagDecl->getTagKind(); 4356 else { 4357 // Recover by making this an anonymous redefinition. 4358 Name = 0; 4359 PrevDecl = 0; 4360 Invalid = true; 4361 } 4362 } 4363 4364 if (!Invalid) { 4365 // If this is a use, just return the declaration we found. 4366 4367 // FIXME: In the future, return a variant or some other clue 4368 // for the consumer of this Decl to know it doesn't own it. 4369 // For our current ASTs this shouldn't be a problem, but will 4370 // need to be changed with DeclGroups. 4371 if (TUK == TUK_Reference || TUK == TUK_Friend) 4372 return DeclPtrTy::make(PrevDecl); 4373 4374 // Diagnose attempts to redefine a tag. 4375 if (TUK == TUK_Definition) { 4376 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4377 // If we're defining a specialization and the previous definition 4378 // is from an implicit instantiation, don't emit an error 4379 // here; we'll catch this in the general case below. 4380 if (!isExplicitSpecialization || 4381 !isa<CXXRecordDecl>(Def) || 4382 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4383 == TSK_ExplicitSpecialization) { 4384 Diag(NameLoc, diag::err_redefinition) << Name; 4385 Diag(Def->getLocation(), diag::note_previous_definition); 4386 // If this is a redefinition, recover by making this 4387 // struct be anonymous, which will make any later 4388 // references get the previous definition. 4389 Name = 0; 4390 PrevDecl = 0; 4391 Invalid = true; 4392 } 4393 } else { 4394 // If the type is currently being defined, complain 4395 // about a nested redefinition. 4396 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4397 if (Tag->isBeingDefined()) { 4398 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4399 Diag(PrevTagDecl->getLocation(), 4400 diag::note_previous_definition); 4401 Name = 0; 4402 PrevDecl = 0; 4403 Invalid = true; 4404 } 4405 } 4406 4407 // Okay, this is definition of a previously declared or referenced 4408 // tag PrevDecl. We're going to create a new Decl for it. 4409 } 4410 } 4411 // If we get here we have (another) forward declaration or we 4412 // have a definition. Just create a new decl. 4413 4414 } else { 4415 // If we get here, this is a definition of a new tag type in a nested 4416 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4417 // new decl/type. We set PrevDecl to NULL so that the entities 4418 // have distinct types. 4419 PrevDecl = 0; 4420 } 4421 // If we get here, we're going to create a new Decl. If PrevDecl 4422 // is non-NULL, it's a definition of the tag declared by 4423 // PrevDecl. If it's NULL, we have a new definition. 4424 } else { 4425 // PrevDecl is a namespace, template, or anything else 4426 // that lives in the IDNS_Tag identifier namespace. 4427 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4428 // The tag name clashes with a namespace name, issue an error and 4429 // recover by making this tag be anonymous. 4430 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4431 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4432 Name = 0; 4433 PrevDecl = 0; 4434 Invalid = true; 4435 } else { 4436 // The existing declaration isn't relevant to us; we're in a 4437 // new scope, so clear out the previous declaration. 4438 PrevDecl = 0; 4439 } 4440 } 4441 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4442 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4443 // C++ [basic.scope.pdecl]p5: 4444 // -- for an elaborated-type-specifier of the form 4445 // 4446 // class-key identifier 4447 // 4448 // if the elaborated-type-specifier is used in the 4449 // decl-specifier-seq or parameter-declaration-clause of a 4450 // function defined in namespace scope, the identifier is 4451 // declared as a class-name in the namespace that contains 4452 // the declaration; otherwise, except as a friend 4453 // declaration, the identifier is declared in the smallest 4454 // non-class, non-function-prototype scope that contains the 4455 // declaration. 4456 // 4457 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4458 // C structs and unions. 4459 // 4460 // GNU C also supports this behavior as part of its incomplete 4461 // enum types extension, while GNU C++ does not. 4462 // 4463 // Find the context where we'll be declaring the tag. 4464 // FIXME: We would like to maintain the current DeclContext as the 4465 // lexical context, 4466 while (SearchDC->isRecord()) 4467 SearchDC = SearchDC->getParent(); 4468 4469 // Find the scope where we'll be declaring the tag. 4470 while (S->isClassScope() || 4471 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4472 ((S->getFlags() & Scope::DeclScope) == 0) || 4473 (S->getEntity() && 4474 ((DeclContext *)S->getEntity())->isTransparentContext())) 4475 S = S->getParent(); 4476 4477 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4478 // C++ [namespace.memdef]p3: 4479 // If a friend declaration in a non-local class first declares a 4480 // class or function, the friend class or function is a member of 4481 // the innermost enclosing namespace. 4482 while (!SearchDC->isFileContext()) 4483 SearchDC = SearchDC->getParent(); 4484 4485 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4486 while (S->getEntity() != SearchDC) 4487 S = S->getParent(); 4488 } 4489 4490CreateNewDecl: 4491 4492 // If there is an identifier, use the location of the identifier as the 4493 // location of the decl, otherwise use the location of the struct/union 4494 // keyword. 4495 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4496 4497 // Otherwise, create a new declaration. If there is a previous 4498 // declaration of the same entity, the two will be linked via 4499 // PrevDecl. 4500 TagDecl *New; 4501 4502 if (Kind == TagDecl::TK_enum) { 4503 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4504 // enum X { A, B, C } D; D should chain to X. 4505 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4506 cast_or_null<EnumDecl>(PrevDecl)); 4507 // If this is an undefined enum, warn. 4508 if (TUK != TUK_Definition && !Invalid) { 4509 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4510 : diag::ext_forward_ref_enum; 4511 Diag(Loc, DK); 4512 } 4513 } else { 4514 // struct/union/class 4515 4516 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4517 // struct X { int A; } D; D should chain to X. 4518 if (getLangOptions().CPlusPlus) { 4519 // FIXME: Look for a way to use RecordDecl for simple structs. 4520 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4521 cast_or_null<CXXRecordDecl>(PrevDecl)); 4522 4523 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4524 StdBadAlloc = cast<CXXRecordDecl>(New); 4525 } else 4526 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4527 cast_or_null<RecordDecl>(PrevDecl)); 4528 } 4529 4530 if (Kind != TagDecl::TK_enum) { 4531 // Handle #pragma pack: if the #pragma pack stack has non-default 4532 // alignment, make up a packed attribute for this decl. These 4533 // attributes are checked when the ASTContext lays out the 4534 // structure. 4535 // 4536 // It is important for implementing the correct semantics that this 4537 // happen here (in act on tag decl). The #pragma pack stack is 4538 // maintained as a result of parser callbacks which can occur at 4539 // many points during the parsing of a struct declaration (because 4540 // the #pragma tokens are effectively skipped over during the 4541 // parsing of the struct). 4542 if (unsigned Alignment = getPragmaPackAlignment()) 4543 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4544 } 4545 4546 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4547 // C++ [dcl.typedef]p3: 4548 // [...] Similarly, in a given scope, a class or enumeration 4549 // shall not be declared with the same name as a typedef-name 4550 // that is declared in that scope and refers to a type other 4551 // than the class or enumeration itself. 4552 LookupResult Lookup; 4553 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4554 TypedefDecl *PrevTypedef = 0; 4555 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4556 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4557 4558 NamedDecl *PrevTypedefNamed = PrevTypedef; 4559 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4560 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4561 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4562 Diag(Loc, diag::err_tag_definition_of_typedef) 4563 << Context.getTypeDeclType(New) 4564 << PrevTypedef->getUnderlyingType(); 4565 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4566 Invalid = true; 4567 } 4568 } 4569 4570 // If this is a specialization of a member class (of a class template), 4571 // check the specialization. 4572 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4573 Invalid = true; 4574 4575 if (Invalid) 4576 New->setInvalidDecl(); 4577 4578 if (Attr) 4579 ProcessDeclAttributeList(S, New, Attr); 4580 4581 // If we're declaring or defining a tag in function prototype scope 4582 // in C, note that this type can only be used within the function. 4583 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4584 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4585 4586 // Set the lexical context. If the tag has a C++ scope specifier, the 4587 // lexical context will be different from the semantic context. 4588 New->setLexicalDeclContext(CurContext); 4589 4590 // Mark this as a friend decl if applicable. 4591 if (TUK == TUK_Friend) 4592 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4593 4594 // Set the access specifier. 4595 if (!Invalid && TUK != TUK_Friend) 4596 SetMemberAccessSpecifier(New, PrevDecl, AS); 4597 4598 if (TUK == TUK_Definition) 4599 New->startDefinition(); 4600 4601 // If this has an identifier, add it to the scope stack. 4602 if (TUK == TUK_Friend) { 4603 // We might be replacing an existing declaration in the lookup tables; 4604 // if so, borrow its access specifier. 4605 if (PrevDecl) 4606 New->setAccess(PrevDecl->getAccess()); 4607 4608 // Friend tag decls are visible in fairly strange ways. 4609 if (!CurContext->isDependentContext()) { 4610 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4611 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4612 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4613 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4614 } 4615 } else if (Name) { 4616 S = getNonFieldDeclScope(S); 4617 PushOnScopeChains(New, S); 4618 } else { 4619 CurContext->addDecl(New); 4620 } 4621 4622 // If this is the C FILE type, notify the AST context. 4623 if (IdentifierInfo *II = New->getIdentifier()) 4624 if (!New->isInvalidDecl() && 4625 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4626 II->isStr("FILE")) 4627 Context.setFILEDecl(New); 4628 4629 OwnedDecl = true; 4630 return DeclPtrTy::make(New); 4631} 4632 4633void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4634 AdjustDeclIfTemplate(TagD); 4635 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4636 4637 // Enter the tag context. 4638 PushDeclContext(S, Tag); 4639 4640 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4641 FieldCollector->StartClass(); 4642 4643 if (Record->getIdentifier()) { 4644 // C++ [class]p2: 4645 // [...] The class-name is also inserted into the scope of the 4646 // class itself; this is known as the injected-class-name. For 4647 // purposes of access checking, the injected-class-name is treated 4648 // as if it were a public member name. 4649 CXXRecordDecl *InjectedClassName 4650 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4651 CurContext, Record->getLocation(), 4652 Record->getIdentifier(), 4653 Record->getTagKeywordLoc(), 4654 Record); 4655 InjectedClassName->setImplicit(); 4656 InjectedClassName->setAccess(AS_public); 4657 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4658 InjectedClassName->setDescribedClassTemplate(Template); 4659 PushOnScopeChains(InjectedClassName, S); 4660 assert(InjectedClassName->isInjectedClassName() && 4661 "Broken injected-class-name"); 4662 } 4663 } 4664} 4665 4666void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4667 SourceLocation RBraceLoc) { 4668 AdjustDeclIfTemplate(TagD); 4669 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4670 Tag->setRBraceLoc(RBraceLoc); 4671 4672 if (isa<CXXRecordDecl>(Tag)) 4673 FieldCollector->FinishClass(); 4674 4675 // Exit this scope of this tag's definition. 4676 PopDeclContext(); 4677 4678 // Notify the consumer that we've defined a tag. 4679 Consumer.HandleTagDeclDefinition(Tag); 4680} 4681 4682// Note that FieldName may be null for anonymous bitfields. 4683bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4684 QualType FieldTy, const Expr *BitWidth, 4685 bool *ZeroWidth) { 4686 // Default to true; that shouldn't confuse checks for emptiness 4687 if (ZeroWidth) 4688 *ZeroWidth = true; 4689 4690 // C99 6.7.2.1p4 - verify the field type. 4691 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4692 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4693 // Handle incomplete types with specific error. 4694 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4695 return true; 4696 if (FieldName) 4697 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4698 << FieldName << FieldTy << BitWidth->getSourceRange(); 4699 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4700 << FieldTy << BitWidth->getSourceRange(); 4701 } 4702 4703 // If the bit-width is type- or value-dependent, don't try to check 4704 // it now. 4705 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4706 return false; 4707 4708 llvm::APSInt Value; 4709 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4710 return true; 4711 4712 if (Value != 0 && ZeroWidth) 4713 *ZeroWidth = false; 4714 4715 // Zero-width bitfield is ok for anonymous field. 4716 if (Value == 0 && FieldName) 4717 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4718 4719 if (Value.isSigned() && Value.isNegative()) { 4720 if (FieldName) 4721 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4722 << FieldName << Value.toString(10); 4723 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4724 << Value.toString(10); 4725 } 4726 4727 if (!FieldTy->isDependentType()) { 4728 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4729 if (Value.getZExtValue() > TypeSize) { 4730 if (FieldName) 4731 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4732 << FieldName << (unsigned)TypeSize; 4733 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4734 << (unsigned)TypeSize; 4735 } 4736 } 4737 4738 return false; 4739} 4740 4741/// ActOnField - Each field of a struct/union/class is passed into this in order 4742/// to create a FieldDecl object for it. 4743Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4744 SourceLocation DeclStart, 4745 Declarator &D, ExprTy *BitfieldWidth) { 4746 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4747 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4748 AS_public); 4749 return DeclPtrTy::make(Res); 4750} 4751 4752/// HandleField - Analyze a field of a C struct or a C++ data member. 4753/// 4754FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4755 SourceLocation DeclStart, 4756 Declarator &D, Expr *BitWidth, 4757 AccessSpecifier AS) { 4758 IdentifierInfo *II = D.getIdentifier(); 4759 SourceLocation Loc = DeclStart; 4760 if (II) Loc = D.getIdentifierLoc(); 4761 4762 DeclaratorInfo *DInfo = 0; 4763 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4764 if (getLangOptions().CPlusPlus) 4765 CheckExtraCXXDefaultArguments(D); 4766 4767 DiagnoseFunctionSpecifiers(D); 4768 4769 if (D.getDeclSpec().isThreadSpecified()) 4770 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4771 4772 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4773 4774 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4775 // Maybe we will complain about the shadowed template parameter. 4776 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4777 // Just pretend that we didn't see the previous declaration. 4778 PrevDecl = 0; 4779 } 4780 4781 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4782 PrevDecl = 0; 4783 4784 bool Mutable 4785 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4786 SourceLocation TSSL = D.getSourceRange().getBegin(); 4787 FieldDecl *NewFD 4788 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4789 AS, PrevDecl, &D); 4790 if (NewFD->isInvalidDecl() && PrevDecl) { 4791 // Don't introduce NewFD into scope; there's already something 4792 // with the same name in the same scope. 4793 } else if (II) { 4794 PushOnScopeChains(NewFD, S); 4795 } else 4796 Record->addDecl(NewFD); 4797 4798 return NewFD; 4799} 4800 4801/// \brief Build a new FieldDecl and check its well-formedness. 4802/// 4803/// This routine builds a new FieldDecl given the fields name, type, 4804/// record, etc. \p PrevDecl should refer to any previous declaration 4805/// with the same name and in the same scope as the field to be 4806/// created. 4807/// 4808/// \returns a new FieldDecl. 4809/// 4810/// \todo The Declarator argument is a hack. It will be removed once 4811FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4812 DeclaratorInfo *DInfo, 4813 RecordDecl *Record, SourceLocation Loc, 4814 bool Mutable, Expr *BitWidth, 4815 SourceLocation TSSL, 4816 AccessSpecifier AS, NamedDecl *PrevDecl, 4817 Declarator *D) { 4818 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4819 bool InvalidDecl = false; 4820 if (D) InvalidDecl = D->isInvalidType(); 4821 4822 // If we receive a broken type, recover by assuming 'int' and 4823 // marking this declaration as invalid. 4824 if (T.isNull()) { 4825 InvalidDecl = true; 4826 T = Context.IntTy; 4827 } 4828 4829 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4830 // than a variably modified type. 4831 if (T->isVariablyModifiedType()) { 4832 bool SizeIsNegative; 4833 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4834 SizeIsNegative); 4835 if (!FixedTy.isNull()) { 4836 Diag(Loc, diag::warn_illegal_constant_array_size); 4837 T = FixedTy; 4838 } else { 4839 if (SizeIsNegative) 4840 Diag(Loc, diag::err_typecheck_negative_array_size); 4841 else 4842 Diag(Loc, diag::err_typecheck_field_variable_size); 4843 InvalidDecl = true; 4844 } 4845 } 4846 4847 // Fields can not have abstract class types 4848 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4849 AbstractFieldType)) 4850 InvalidDecl = true; 4851 4852 bool ZeroWidth = false; 4853 // If this is declared as a bit-field, check the bit-field. 4854 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4855 InvalidDecl = true; 4856 DeleteExpr(BitWidth); 4857 BitWidth = 0; 4858 ZeroWidth = false; 4859 } 4860 4861 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4862 BitWidth, Mutable); 4863 if (InvalidDecl) 4864 NewFD->setInvalidDecl(); 4865 4866 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4867 Diag(Loc, diag::err_duplicate_member) << II; 4868 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4869 NewFD->setInvalidDecl(); 4870 } 4871 4872 if (getLangOptions().CPlusPlus) { 4873 QualType EltTy = Context.getBaseElementType(T); 4874 4875 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4876 4877 if (!T->isPODType()) 4878 CXXRecord->setPOD(false); 4879 if (!ZeroWidth) 4880 CXXRecord->setEmpty(false); 4881 4882 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4883 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4884 4885 if (!RDecl->hasTrivialConstructor()) 4886 CXXRecord->setHasTrivialConstructor(false); 4887 if (!RDecl->hasTrivialCopyConstructor()) 4888 CXXRecord->setHasTrivialCopyConstructor(false); 4889 if (!RDecl->hasTrivialCopyAssignment()) 4890 CXXRecord->setHasTrivialCopyAssignment(false); 4891 if (!RDecl->hasTrivialDestructor()) 4892 CXXRecord->setHasTrivialDestructor(false); 4893 4894 // C++ 9.5p1: An object of a class with a non-trivial 4895 // constructor, a non-trivial copy constructor, a non-trivial 4896 // destructor, or a non-trivial copy assignment operator 4897 // cannot be a member of a union, nor can an array of such 4898 // objects. 4899 // TODO: C++0x alters this restriction significantly. 4900 if (Record->isUnion()) { 4901 // We check for copy constructors before constructors 4902 // because otherwise we'll never get complaints about 4903 // copy constructors. 4904 4905 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4906 4907 CXXSpecialMember member; 4908 if (!RDecl->hasTrivialCopyConstructor()) 4909 member = CXXCopyConstructor; 4910 else if (!RDecl->hasTrivialConstructor()) 4911 member = CXXDefaultConstructor; 4912 else if (!RDecl->hasTrivialCopyAssignment()) 4913 member = CXXCopyAssignment; 4914 else if (!RDecl->hasTrivialDestructor()) 4915 member = CXXDestructor; 4916 else 4917 member = invalid; 4918 4919 if (member != invalid) { 4920 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4921 DiagnoseNontrivial(RT, member); 4922 NewFD->setInvalidDecl(); 4923 } 4924 } 4925 } 4926 } 4927 4928 // FIXME: We need to pass in the attributes given an AST 4929 // representation, not a parser representation. 4930 if (D) 4931 // FIXME: What to pass instead of TUScope? 4932 ProcessDeclAttributes(TUScope, NewFD, *D); 4933 4934 if (T.isObjCGCWeak()) 4935 Diag(Loc, diag::warn_attribute_weak_on_field); 4936 4937 NewFD->setAccess(AS); 4938 4939 // C++ [dcl.init.aggr]p1: 4940 // An aggregate is an array or a class (clause 9) with [...] no 4941 // private or protected non-static data members (clause 11). 4942 // A POD must be an aggregate. 4943 if (getLangOptions().CPlusPlus && 4944 (AS == AS_private || AS == AS_protected)) { 4945 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4946 CXXRecord->setAggregate(false); 4947 CXXRecord->setPOD(false); 4948 } 4949 4950 return NewFD; 4951} 4952 4953/// DiagnoseNontrivial - Given that a class has a non-trivial 4954/// special member, figure out why. 4955void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4956 QualType QT(T, 0U); 4957 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4958 4959 // Check whether the member was user-declared. 4960 switch (member) { 4961 case CXXDefaultConstructor: 4962 if (RD->hasUserDeclaredConstructor()) { 4963 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4964 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 4965 const FunctionDecl *body = 0; 4966 ci->getBody(body); 4967 if (!body || 4968 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 4969 SourceLocation CtorLoc = ci->getLocation(); 4970 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4971 return; 4972 } 4973 } 4974 4975 assert(0 && "found no user-declared constructors"); 4976 return; 4977 } 4978 break; 4979 4980 case CXXCopyConstructor: 4981 if (RD->hasUserDeclaredCopyConstructor()) { 4982 SourceLocation CtorLoc = 4983 RD->getCopyConstructor(Context, 0)->getLocation(); 4984 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4985 return; 4986 } 4987 break; 4988 4989 case CXXCopyAssignment: 4990 if (RD->hasUserDeclaredCopyAssignment()) { 4991 // FIXME: this should use the location of the copy 4992 // assignment, not the type. 4993 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4994 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4995 return; 4996 } 4997 break; 4998 4999 case CXXDestructor: 5000 if (RD->hasUserDeclaredDestructor()) { 5001 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5002 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5003 return; 5004 } 5005 break; 5006 } 5007 5008 typedef CXXRecordDecl::base_class_iterator base_iter; 5009 5010 // Virtual bases and members inhibit trivial copying/construction, 5011 // but not trivial destruction. 5012 if (member != CXXDestructor) { 5013 // Check for virtual bases. vbases includes indirect virtual bases, 5014 // so we just iterate through the direct bases. 5015 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5016 if (bi->isVirtual()) { 5017 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5018 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5019 return; 5020 } 5021 5022 // Check for virtual methods. 5023 typedef CXXRecordDecl::method_iterator meth_iter; 5024 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5025 ++mi) { 5026 if (mi->isVirtual()) { 5027 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5028 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5029 return; 5030 } 5031 } 5032 } 5033 5034 bool (CXXRecordDecl::*hasTrivial)() const; 5035 switch (member) { 5036 case CXXDefaultConstructor: 5037 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5038 case CXXCopyConstructor: 5039 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5040 case CXXCopyAssignment: 5041 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5042 case CXXDestructor: 5043 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5044 default: 5045 assert(0 && "unexpected special member"); return; 5046 } 5047 5048 // Check for nontrivial bases (and recurse). 5049 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5050 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5051 assert(BaseRT && "Don't know how to handle dependent bases"); 5052 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5053 if (!(BaseRecTy->*hasTrivial)()) { 5054 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5055 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5056 DiagnoseNontrivial(BaseRT, member); 5057 return; 5058 } 5059 } 5060 5061 // Check for nontrivial members (and recurse). 5062 typedef RecordDecl::field_iterator field_iter; 5063 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5064 ++fi) { 5065 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5066 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5067 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5068 5069 if (!(EltRD->*hasTrivial)()) { 5070 SourceLocation FLoc = (*fi)->getLocation(); 5071 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5072 DiagnoseNontrivial(EltRT, member); 5073 return; 5074 } 5075 } 5076 } 5077 5078 assert(0 && "found no explanation for non-trivial member"); 5079} 5080 5081/// TranslateIvarVisibility - Translate visibility from a token ID to an 5082/// AST enum value. 5083static ObjCIvarDecl::AccessControl 5084TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5085 switch (ivarVisibility) { 5086 default: assert(0 && "Unknown visitibility kind"); 5087 case tok::objc_private: return ObjCIvarDecl::Private; 5088 case tok::objc_public: return ObjCIvarDecl::Public; 5089 case tok::objc_protected: return ObjCIvarDecl::Protected; 5090 case tok::objc_package: return ObjCIvarDecl::Package; 5091 } 5092} 5093 5094/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5095/// in order to create an IvarDecl object for it. 5096Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5097 SourceLocation DeclStart, 5098 DeclPtrTy IntfDecl, 5099 Declarator &D, ExprTy *BitfieldWidth, 5100 tok::ObjCKeywordKind Visibility) { 5101 5102 IdentifierInfo *II = D.getIdentifier(); 5103 Expr *BitWidth = (Expr*)BitfieldWidth; 5104 SourceLocation Loc = DeclStart; 5105 if (II) Loc = D.getIdentifierLoc(); 5106 5107 // FIXME: Unnamed fields can be handled in various different ways, for 5108 // example, unnamed unions inject all members into the struct namespace! 5109 5110 DeclaratorInfo *DInfo = 0; 5111 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5112 5113 if (BitWidth) { 5114 // 6.7.2.1p3, 6.7.2.1p4 5115 if (VerifyBitField(Loc, II, T, BitWidth)) { 5116 D.setInvalidType(); 5117 DeleteExpr(BitWidth); 5118 BitWidth = 0; 5119 } 5120 } else { 5121 // Not a bitfield. 5122 5123 // validate II. 5124 5125 } 5126 5127 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5128 // than a variably modified type. 5129 if (T->isVariablyModifiedType()) { 5130 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5131 D.setInvalidType(); 5132 } 5133 5134 // Get the visibility (access control) for this ivar. 5135 ObjCIvarDecl::AccessControl ac = 5136 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5137 : ObjCIvarDecl::None; 5138 // Must set ivar's DeclContext to its enclosing interface. 5139 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5140 DeclContext *EnclosingContext; 5141 if (ObjCImplementationDecl *IMPDecl = 5142 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5143 // Case of ivar declared in an implementation. Context is that of its class. 5144 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5145 assert(IDecl && "No class- ActOnIvar"); 5146 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5147 } else 5148 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5149 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5150 5151 // Construct the decl. 5152 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5153 EnclosingContext, Loc, II, T, 5154 DInfo, ac, (Expr *)BitfieldWidth); 5155 5156 if (II) { 5157 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5158 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5159 && !isa<TagDecl>(PrevDecl)) { 5160 Diag(Loc, diag::err_duplicate_member) << II; 5161 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5162 NewID->setInvalidDecl(); 5163 } 5164 } 5165 5166 // Process attributes attached to the ivar. 5167 ProcessDeclAttributes(S, NewID, D); 5168 5169 if (D.isInvalidType()) 5170 NewID->setInvalidDecl(); 5171 5172 if (II) { 5173 // FIXME: When interfaces are DeclContexts, we'll need to add 5174 // these to the interface. 5175 S->AddDecl(DeclPtrTy::make(NewID)); 5176 IdResolver.AddDecl(NewID); 5177 } 5178 5179 return DeclPtrTy::make(NewID); 5180} 5181 5182void Sema::ActOnFields(Scope* S, 5183 SourceLocation RecLoc, DeclPtrTy RecDecl, 5184 DeclPtrTy *Fields, unsigned NumFields, 5185 SourceLocation LBrac, SourceLocation RBrac, 5186 AttributeList *Attr) { 5187 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5188 assert(EnclosingDecl && "missing record or interface decl"); 5189 5190 // If the decl this is being inserted into is invalid, then it may be a 5191 // redeclaration or some other bogus case. Don't try to add fields to it. 5192 if (EnclosingDecl->isInvalidDecl()) { 5193 // FIXME: Deallocate fields? 5194 return; 5195 } 5196 5197 5198 // Verify that all the fields are okay. 5199 unsigned NumNamedMembers = 0; 5200 llvm::SmallVector<FieldDecl*, 32> RecFields; 5201 5202 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5203 for (unsigned i = 0; i != NumFields; ++i) { 5204 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5205 5206 // Get the type for the field. 5207 Type *FDTy = FD->getType().getTypePtr(); 5208 5209 if (!FD->isAnonymousStructOrUnion()) { 5210 // Remember all fields written by the user. 5211 RecFields.push_back(FD); 5212 } 5213 5214 // If the field is already invalid for some reason, don't emit more 5215 // diagnostics about it. 5216 if (FD->isInvalidDecl()) 5217 continue; 5218 5219 // C99 6.7.2.1p2: 5220 // A structure or union shall not contain a member with 5221 // incomplete or function type (hence, a structure shall not 5222 // contain an instance of itself, but may contain a pointer to 5223 // an instance of itself), except that the last member of a 5224 // structure with more than one named member may have incomplete 5225 // array type; such a structure (and any union containing, 5226 // possibly recursively, a member that is such a structure) 5227 // shall not be a member of a structure or an element of an 5228 // array. 5229 if (FDTy->isFunctionType()) { 5230 // Field declared as a function. 5231 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5232 << FD->getDeclName(); 5233 FD->setInvalidDecl(); 5234 EnclosingDecl->setInvalidDecl(); 5235 continue; 5236 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5237 Record && Record->isStruct()) { 5238 // Flexible array member. 5239 if (NumNamedMembers < 1) { 5240 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5241 << FD->getDeclName(); 5242 FD->setInvalidDecl(); 5243 EnclosingDecl->setInvalidDecl(); 5244 continue; 5245 } 5246 // Okay, we have a legal flexible array member at the end of the struct. 5247 if (Record) 5248 Record->setHasFlexibleArrayMember(true); 5249 } else if (!FDTy->isDependentType() && 5250 RequireCompleteType(FD->getLocation(), FD->getType(), 5251 diag::err_field_incomplete)) { 5252 // Incomplete type 5253 FD->setInvalidDecl(); 5254 EnclosingDecl->setInvalidDecl(); 5255 continue; 5256 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5257 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5258 // If this is a member of a union, then entire union becomes "flexible". 5259 if (Record && Record->isUnion()) { 5260 Record->setHasFlexibleArrayMember(true); 5261 } else { 5262 // If this is a struct/class and this is not the last element, reject 5263 // it. Note that GCC supports variable sized arrays in the middle of 5264 // structures. 5265 if (i != NumFields-1) 5266 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5267 << FD->getDeclName() << FD->getType(); 5268 else { 5269 // We support flexible arrays at the end of structs in 5270 // other structs as an extension. 5271 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5272 << FD->getDeclName(); 5273 if (Record) 5274 Record->setHasFlexibleArrayMember(true); 5275 } 5276 } 5277 } 5278 if (Record && FDTTy->getDecl()->hasObjectMember()) 5279 Record->setHasObjectMember(true); 5280 } else if (FDTy->isObjCInterfaceType()) { 5281 /// A field cannot be an Objective-c object 5282 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5283 FD->setInvalidDecl(); 5284 EnclosingDecl->setInvalidDecl(); 5285 continue; 5286 } else if (getLangOptions().ObjC1 && 5287 getLangOptions().getGCMode() != LangOptions::NonGC && 5288 Record && 5289 (FD->getType()->isObjCObjectPointerType() || 5290 FD->getType().isObjCGCStrong())) 5291 Record->setHasObjectMember(true); 5292 // Keep track of the number of named members. 5293 if (FD->getIdentifier()) 5294 ++NumNamedMembers; 5295 } 5296 5297 // Okay, we successfully defined 'Record'. 5298 if (Record) { 5299 Record->completeDefinition(Context); 5300 } else { 5301 ObjCIvarDecl **ClsFields = 5302 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5303 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5304 ID->setIVarList(ClsFields, RecFields.size(), Context); 5305 ID->setLocEnd(RBrac); 5306 // Add ivar's to class's DeclContext. 5307 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5308 ClsFields[i]->setLexicalDeclContext(ID); 5309 ID->addDecl(ClsFields[i]); 5310 } 5311 // Must enforce the rule that ivars in the base classes may not be 5312 // duplicates. 5313 if (ID->getSuperClass()) { 5314 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5315 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5316 ObjCIvarDecl* Ivar = (*IVI); 5317 5318 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5319 ObjCIvarDecl* prevIvar = 5320 ID->getSuperClass()->lookupInstanceVariable(II); 5321 if (prevIvar) { 5322 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5323 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5324 } 5325 } 5326 } 5327 } 5328 } else if (ObjCImplementationDecl *IMPDecl = 5329 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5330 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5331 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5332 // Ivar declared in @implementation never belongs to the implementation. 5333 // Only it is in implementation's lexical context. 5334 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5335 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5336 } 5337 } 5338 5339 if (Attr) 5340 ProcessDeclAttributeList(S, Record, Attr); 5341} 5342 5343EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5344 EnumConstantDecl *LastEnumConst, 5345 SourceLocation IdLoc, 5346 IdentifierInfo *Id, 5347 ExprArg val) { 5348 Expr *Val = (Expr *)val.get(); 5349 5350 llvm::APSInt EnumVal(32); 5351 QualType EltTy; 5352 if (Val && !Val->isTypeDependent()) { 5353 // Make sure to promote the operand type to int. 5354 UsualUnaryConversions(Val); 5355 if (Val != val.get()) { 5356 val.release(); 5357 val = Val; 5358 } 5359 5360 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5361 SourceLocation ExpLoc; 5362 if (!Val->isValueDependent() && 5363 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5364 Val = 0; 5365 } else { 5366 EltTy = Val->getType(); 5367 } 5368 } 5369 5370 if (!Val) { 5371 if (LastEnumConst) { 5372 // Assign the last value + 1. 5373 EnumVal = LastEnumConst->getInitVal(); 5374 ++EnumVal; 5375 5376 // Check for overflow on increment. 5377 if (EnumVal < LastEnumConst->getInitVal()) 5378 Diag(IdLoc, diag::warn_enum_value_overflow); 5379 5380 EltTy = LastEnumConst->getType(); 5381 } else { 5382 // First value, set to zero. 5383 EltTy = Context.IntTy; 5384 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5385 } 5386 } 5387 5388 val.release(); 5389 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5390 Val, EnumVal); 5391} 5392 5393 5394Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5395 DeclPtrTy lastEnumConst, 5396 SourceLocation IdLoc, 5397 IdentifierInfo *Id, 5398 SourceLocation EqualLoc, ExprTy *val) { 5399 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5400 EnumConstantDecl *LastEnumConst = 5401 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5402 Expr *Val = static_cast<Expr*>(val); 5403 5404 // The scope passed in may not be a decl scope. Zip up the scope tree until 5405 // we find one that is. 5406 S = getNonFieldDeclScope(S); 5407 5408 // Verify that there isn't already something declared with this name in this 5409 // scope. 5410 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5411 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5412 // Maybe we will complain about the shadowed template parameter. 5413 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5414 // Just pretend that we didn't see the previous declaration. 5415 PrevDecl = 0; 5416 } 5417 5418 if (PrevDecl) { 5419 // When in C++, we may get a TagDecl with the same name; in this case the 5420 // enum constant will 'hide' the tag. 5421 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5422 "Received TagDecl when not in C++!"); 5423 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5424 if (isa<EnumConstantDecl>(PrevDecl)) 5425 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5426 else 5427 Diag(IdLoc, diag::err_redefinition) << Id; 5428 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5429 if (Val) Val->Destroy(Context); 5430 return DeclPtrTy(); 5431 } 5432 } 5433 5434 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5435 IdLoc, Id, Owned(Val)); 5436 5437 // Register this decl in the current scope stack. 5438 if (New) 5439 PushOnScopeChains(New, S); 5440 5441 return DeclPtrTy::make(New); 5442} 5443 5444void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5445 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5446 DeclPtrTy *Elements, unsigned NumElements, 5447 Scope *S, AttributeList *Attr) { 5448 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5449 QualType EnumType = Context.getTypeDeclType(Enum); 5450 5451 if (Attr) 5452 ProcessDeclAttributeList(S, Enum, Attr); 5453 5454 // TODO: If the result value doesn't fit in an int, it must be a long or long 5455 // long value. ISO C does not support this, but GCC does as an extension, 5456 // emit a warning. 5457 unsigned IntWidth = Context.Target.getIntWidth(); 5458 unsigned CharWidth = Context.Target.getCharWidth(); 5459 unsigned ShortWidth = Context.Target.getShortWidth(); 5460 5461 // Verify that all the values are okay, compute the size of the values, and 5462 // reverse the list. 5463 unsigned NumNegativeBits = 0; 5464 unsigned NumPositiveBits = 0; 5465 5466 // Keep track of whether all elements have type int. 5467 bool AllElementsInt = true; 5468 5469 for (unsigned i = 0; i != NumElements; ++i) { 5470 EnumConstantDecl *ECD = 5471 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5472 if (!ECD) continue; // Already issued a diagnostic. 5473 5474 // If the enum value doesn't fit in an int, emit an extension warning. 5475 const llvm::APSInt &InitVal = ECD->getInitVal(); 5476 assert(InitVal.getBitWidth() >= IntWidth && 5477 "Should have promoted value to int"); 5478 if (InitVal.getBitWidth() > IntWidth) { 5479 llvm::APSInt V(InitVal); 5480 V.trunc(IntWidth); 5481 V.extend(InitVal.getBitWidth()); 5482 if (V != InitVal) 5483 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5484 << InitVal.toString(10); 5485 } 5486 5487 // Keep track of the size of positive and negative values. 5488 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5489 NumPositiveBits = std::max(NumPositiveBits, 5490 (unsigned)InitVal.getActiveBits()); 5491 else 5492 NumNegativeBits = std::max(NumNegativeBits, 5493 (unsigned)InitVal.getMinSignedBits()); 5494 5495 // Keep track of whether every enum element has type int (very commmon). 5496 if (AllElementsInt) 5497 AllElementsInt = ECD->getType() == Context.IntTy; 5498 } 5499 5500 // Figure out the type that should be used for this enum. 5501 // FIXME: Support -fshort-enums. 5502 QualType BestType; 5503 unsigned BestWidth; 5504 5505 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5506 5507 if (NumNegativeBits) { 5508 // If there is a negative value, figure out the smallest integer type (of 5509 // int/long/longlong) that fits. 5510 // If it's packed, check also if it fits a char or a short. 5511 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5512 BestType = Context.SignedCharTy; 5513 BestWidth = CharWidth; 5514 } else if (Packed && NumNegativeBits <= ShortWidth && 5515 NumPositiveBits < ShortWidth) { 5516 BestType = Context.ShortTy; 5517 BestWidth = ShortWidth; 5518 } 5519 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5520 BestType = Context.IntTy; 5521 BestWidth = IntWidth; 5522 } else { 5523 BestWidth = Context.Target.getLongWidth(); 5524 5525 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5526 BestType = Context.LongTy; 5527 else { 5528 BestWidth = Context.Target.getLongLongWidth(); 5529 5530 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5531 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5532 BestType = Context.LongLongTy; 5533 } 5534 } 5535 } else { 5536 // If there is no negative value, figure out which of uint, ulong, ulonglong 5537 // fits. 5538 // If it's packed, check also if it fits a char or a short. 5539 if (Packed && NumPositiveBits <= CharWidth) { 5540 BestType = Context.UnsignedCharTy; 5541 BestWidth = CharWidth; 5542 } else if (Packed && NumPositiveBits <= ShortWidth) { 5543 BestType = Context.UnsignedShortTy; 5544 BestWidth = ShortWidth; 5545 } 5546 else if (NumPositiveBits <= IntWidth) { 5547 BestType = Context.UnsignedIntTy; 5548 BestWidth = IntWidth; 5549 } else if (NumPositiveBits <= 5550 (BestWidth = Context.Target.getLongWidth())) { 5551 BestType = Context.UnsignedLongTy; 5552 } else { 5553 BestWidth = Context.Target.getLongLongWidth(); 5554 assert(NumPositiveBits <= BestWidth && 5555 "How could an initializer get larger than ULL?"); 5556 BestType = Context.UnsignedLongLongTy; 5557 } 5558 } 5559 5560 // Loop over all of the enumerator constants, changing their types to match 5561 // the type of the enum if needed. 5562 for (unsigned i = 0; i != NumElements; ++i) { 5563 EnumConstantDecl *ECD = 5564 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5565 if (!ECD) continue; // Already issued a diagnostic. 5566 5567 // Standard C says the enumerators have int type, but we allow, as an 5568 // extension, the enumerators to be larger than int size. If each 5569 // enumerator value fits in an int, type it as an int, otherwise type it the 5570 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5571 // that X has type 'int', not 'unsigned'. 5572 if (ECD->getType() == Context.IntTy) { 5573 // Make sure the init value is signed. 5574 llvm::APSInt IV = ECD->getInitVal(); 5575 IV.setIsSigned(true); 5576 ECD->setInitVal(IV); 5577 5578 if (getLangOptions().CPlusPlus) 5579 // C++ [dcl.enum]p4: Following the closing brace of an 5580 // enum-specifier, each enumerator has the type of its 5581 // enumeration. 5582 ECD->setType(EnumType); 5583 continue; // Already int type. 5584 } 5585 5586 // Determine whether the value fits into an int. 5587 llvm::APSInt InitVal = ECD->getInitVal(); 5588 bool FitsInInt; 5589 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5590 FitsInInt = InitVal.getActiveBits() < IntWidth; 5591 else 5592 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5593 5594 // If it fits into an integer type, force it. Otherwise force it to match 5595 // the enum decl type. 5596 QualType NewTy; 5597 unsigned NewWidth; 5598 bool NewSign; 5599 if (FitsInInt) { 5600 NewTy = Context.IntTy; 5601 NewWidth = IntWidth; 5602 NewSign = true; 5603 } else if (ECD->getType() == BestType) { 5604 // Already the right type! 5605 if (getLangOptions().CPlusPlus) 5606 // C++ [dcl.enum]p4: Following the closing brace of an 5607 // enum-specifier, each enumerator has the type of its 5608 // enumeration. 5609 ECD->setType(EnumType); 5610 continue; 5611 } else { 5612 NewTy = BestType; 5613 NewWidth = BestWidth; 5614 NewSign = BestType->isSignedIntegerType(); 5615 } 5616 5617 // Adjust the APSInt value. 5618 InitVal.extOrTrunc(NewWidth); 5619 InitVal.setIsSigned(NewSign); 5620 ECD->setInitVal(InitVal); 5621 5622 // Adjust the Expr initializer and type. 5623 if (ECD->getInitExpr()) 5624 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5625 CastExpr::CK_IntegralCast, 5626 ECD->getInitExpr(), 5627 /*isLvalue=*/false)); 5628 if (getLangOptions().CPlusPlus) 5629 // C++ [dcl.enum]p4: Following the closing brace of an 5630 // enum-specifier, each enumerator has the type of its 5631 // enumeration. 5632 ECD->setType(EnumType); 5633 else 5634 ECD->setType(NewTy); 5635 } 5636 5637 Enum->completeDefinition(Context, BestType); 5638} 5639 5640Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5641 ExprArg expr) { 5642 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5643 5644 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5645 Loc, AsmString); 5646 CurContext->addDecl(New); 5647 return DeclPtrTy::make(New); 5648} 5649 5650void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5651 SourceLocation PragmaLoc, 5652 SourceLocation NameLoc) { 5653 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5654 5655 if (PrevDecl) { 5656 PrevDecl->addAttr(::new (Context) WeakAttr()); 5657 } else { 5658 (void)WeakUndeclaredIdentifiers.insert( 5659 std::pair<IdentifierInfo*,WeakInfo> 5660 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5661 } 5662} 5663 5664void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5665 IdentifierInfo* AliasName, 5666 SourceLocation PragmaLoc, 5667 SourceLocation NameLoc, 5668 SourceLocation AliasNameLoc) { 5669 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5670 WeakInfo W = WeakInfo(Name, NameLoc); 5671 5672 if (PrevDecl) { 5673 if (!PrevDecl->hasAttr<AliasAttr>()) 5674 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5675 DeclApplyPragmaWeak(TUScope, ND, W); 5676 } else { 5677 (void)WeakUndeclaredIdentifiers.insert( 5678 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5679 } 5680} 5681