SemaDecl.cpp revision 37f55c4efd4603ae0a9206d19d6568d2aec57442
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/// MaybeFallThroughOrReturn iff we might or might not fall off the end and 1048/// MaybeFallThrough iff we might or might not fall off the end and 1049/// NeverFallThrough iff we never fall off the end of the statement. We assume 1050/// that functions not marked noreturn will return. 1051Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1052 // FIXME: Eventually share this CFG object when we have other warnings based 1053 // of the CFG. This can be done using AnalysisContext. 1054 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1055 1056 // FIXME: They should never return 0, fix that, delete this code. 1057 if (cfg == 0) 1058 // FIXME: This should be NeverFallThrough 1059 return NeverFallThroughOrReturn; 1060 // The CFG leaves in dead things, and we don't want to dead code paths to 1061 // confuse us, so we mark all live things first. 1062 std::queue<CFGBlock*> workq; 1063 llvm::BitVector live(cfg->getNumBlockIDs()); 1064 // Prep work queue 1065 workq.push(&cfg->getEntry()); 1066 // Solve 1067 while (!workq.empty()) { 1068 CFGBlock *item = workq.front(); 1069 workq.pop(); 1070 live.set(item->getBlockID()); 1071 for (CFGBlock::succ_iterator I=item->succ_begin(), 1072 E=item->succ_end(); 1073 I != E; 1074 ++I) { 1075 if ((*I) && !live[(*I)->getBlockID()]) { 1076 live.set((*I)->getBlockID()); 1077 workq.push(*I); 1078 } 1079 } 1080 } 1081 1082 // Now we know what is live, we check the live precessors of the exit block 1083 // and look for fall through paths, being careful to ignore normal returns, 1084 // and exceptional paths. 1085 bool HasLiveReturn = false; 1086 bool HasFakeEdge = false; 1087 bool HasPlainEdge = false; 1088 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1089 E = cfg->getExit().pred_end(); 1090 I != E; 1091 ++I) { 1092 CFGBlock& B = **I; 1093 if (!live[B.getBlockID()]) 1094 continue; 1095 if (B.size() == 0) { 1096 // A labeled empty statement, or the entry block... 1097 HasPlainEdge = true; 1098 continue; 1099 } 1100 Stmt *S = B[B.size()-1]; 1101 if (isa<ReturnStmt>(S)) { 1102 HasLiveReturn = true; 1103 continue; 1104 } 1105 if (isa<ObjCAtThrowStmt>(S)) { 1106 HasFakeEdge = true; 1107 continue; 1108 } 1109 if (isa<CXXThrowExpr>(S)) { 1110 HasFakeEdge = true; 1111 continue; 1112 } 1113 bool NoReturnEdge = false; 1114 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1115 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1116 if (CEE->getType().getNoReturnAttr()) { 1117 NoReturnEdge = true; 1118 HasFakeEdge = true; 1119 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1120 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1121 if (FD->hasAttr<NoReturnAttr>()) { 1122 NoReturnEdge = true; 1123 HasFakeEdge = true; 1124 } 1125 } 1126 } 1127 } 1128 // FIXME: Add noreturn message sends. 1129 if (NoReturnEdge == false) 1130 HasPlainEdge = true; 1131 } 1132 if (!HasPlainEdge) { 1133 if (HasLiveReturn) 1134 return NeverFallThrough; 1135 return NeverFallThroughOrReturn; 1136 } 1137 if (HasFakeEdge || HasLiveReturn) 1138 return MaybeFallThrough; 1139 // This says AlwaysFallThrough for calls to functions that are not marked 1140 // noreturn, that don't return. If people would like this warning to be more 1141 // accurate, such functions should be marked as noreturn. 1142 return AlwaysFallThrough; 1143} 1144 1145/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1146/// function that should return a value. Check that we don't fall off the end 1147/// of a noreturn function. We assume that functions and blocks not marked 1148/// noreturn will return. 1149void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1150 // FIXME: Would be nice if we had a better way to control cascading errors, 1151 // but for now, avoid them. The problem is that when Parse sees: 1152 // int foo() { return a; } 1153 // The return is eaten and the Sema code sees just: 1154 // int foo() { } 1155 // which this code would then warn about. 1156 if (getDiagnostics().hasErrorOccurred()) 1157 return; 1158 1159 bool ReturnsVoid = false; 1160 bool HasNoReturn = false; 1161 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1162 // If the result type of the function is a dependent type, we don't know 1163 // whether it will be void or not, so don't 1164 if (FD->getResultType()->isDependentType()) 1165 return; 1166 if (FD->getResultType()->isVoidType()) 1167 ReturnsVoid = true; 1168 if (FD->hasAttr<NoReturnAttr>()) 1169 HasNoReturn = true; 1170 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1171 if (MD->getResultType()->isVoidType()) 1172 ReturnsVoid = true; 1173 if (MD->hasAttr<NoReturnAttr>()) 1174 HasNoReturn = true; 1175 } 1176 1177 // Short circuit for compilation speed. 1178 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1179 == Diagnostic::Ignored || ReturnsVoid) 1180 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1181 == Diagnostic::Ignored || !HasNoReturn) 1182 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1183 == Diagnostic::Ignored || !ReturnsVoid)) 1184 return; 1185 // FIXME: Function try block 1186 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1187 switch (CheckFallThrough(Body)) { 1188 case MaybeFallThrough: 1189 if (HasNoReturn) 1190 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1191 else if (!ReturnsVoid) 1192 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1193 break; 1194 case AlwaysFallThrough: 1195 if (HasNoReturn) 1196 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1197 else if (!ReturnsVoid) 1198 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1199 break; 1200 case NeverFallThroughOrReturn: 1201 if (ReturnsVoid && !HasNoReturn) 1202 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1203 break; 1204 case NeverFallThrough: 1205 break; 1206 } 1207 } 1208} 1209 1210/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1211/// that should return a value. Check that we don't fall off the end of a 1212/// noreturn block. We assume that functions and blocks not marked noreturn 1213/// will return. 1214void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1215 // FIXME: Would be nice if we had a better way to control cascading errors, 1216 // but for now, avoid them. The problem is that when Parse sees: 1217 // int foo() { return a; } 1218 // The return is eaten and the Sema code sees just: 1219 // int foo() { } 1220 // which this code would then warn about. 1221 if (getDiagnostics().hasErrorOccurred()) 1222 return; 1223 bool ReturnsVoid = false; 1224 bool HasNoReturn = false; 1225 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1226 if (FT->getResultType()->isVoidType()) 1227 ReturnsVoid = true; 1228 if (FT->getNoReturnAttr()) 1229 HasNoReturn = true; 1230 } 1231 1232 // Short circuit for compilation speed. 1233 if (ReturnsVoid 1234 && !HasNoReturn 1235 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1236 == Diagnostic::Ignored || !ReturnsVoid)) 1237 return; 1238 // FIXME: Funtion try block 1239 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1240 switch (CheckFallThrough(Body)) { 1241 case MaybeFallThrough: 1242 if (HasNoReturn) 1243 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1244 else if (!ReturnsVoid) 1245 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1246 break; 1247 case AlwaysFallThrough: 1248 if (HasNoReturn) 1249 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1250 else if (!ReturnsVoid) 1251 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1252 break; 1253 case NeverFallThroughOrReturn: 1254 if (ReturnsVoid) 1255 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1256 break; 1257 case NeverFallThrough: 1258 break; 1259 } 1260 } 1261} 1262 1263/// CheckParmsForFunctionDef - Check that the parameters of the given 1264/// function are appropriate for the definition of a function. This 1265/// takes care of any checks that cannot be performed on the 1266/// declaration itself, e.g., that the types of each of the function 1267/// parameters are complete. 1268bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1269 bool HasInvalidParm = false; 1270 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1271 ParmVarDecl *Param = FD->getParamDecl(p); 1272 1273 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1274 // function declarator that is part of a function definition of 1275 // that function shall not have incomplete type. 1276 // 1277 // This is also C++ [dcl.fct]p6. 1278 if (!Param->isInvalidDecl() && 1279 RequireCompleteType(Param->getLocation(), Param->getType(), 1280 diag::err_typecheck_decl_incomplete_type)) { 1281 Param->setInvalidDecl(); 1282 HasInvalidParm = true; 1283 } 1284 1285 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1286 // declaration of each parameter shall include an identifier. 1287 if (Param->getIdentifier() == 0 && 1288 !Param->isImplicit() && 1289 !getLangOptions().CPlusPlus) 1290 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1291 } 1292 1293 return HasInvalidParm; 1294} 1295 1296/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1297/// no declarator (e.g. "struct foo;") is parsed. 1298Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1299 // FIXME: Error on auto/register at file scope 1300 // FIXME: Error on inline/virtual/explicit 1301 // FIXME: Error on invalid restrict 1302 // FIXME: Warn on useless __thread 1303 // FIXME: Warn on useless const/volatile 1304 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1305 // FIXME: Warn on useless attributes 1306 Decl *TagD = 0; 1307 TagDecl *Tag = 0; 1308 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1309 DS.getTypeSpecType() == DeclSpec::TST_struct || 1310 DS.getTypeSpecType() == DeclSpec::TST_union || 1311 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1312 TagD = static_cast<Decl *>(DS.getTypeRep()); 1313 1314 if (!TagD) // We probably had an error 1315 return DeclPtrTy(); 1316 1317 // Note that the above type specs guarantee that the 1318 // type rep is a Decl, whereas in many of the others 1319 // it's a Type. 1320 Tag = dyn_cast<TagDecl>(TagD); 1321 } 1322 1323 if (DS.isFriendSpecified()) { 1324 // If we're dealing with a class template decl, assume that the 1325 // template routines are handling it. 1326 if (TagD && isa<ClassTemplateDecl>(TagD)) 1327 return DeclPtrTy(); 1328 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1329 } 1330 1331 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1332 // If there are attributes in the DeclSpec, apply them to the record. 1333 if (const AttributeList *AL = DS.getAttributes()) 1334 ProcessDeclAttributeList(S, Record, AL); 1335 1336 if (!Record->getDeclName() && Record->isDefinition() && 1337 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1338 if (getLangOptions().CPlusPlus || 1339 Record->getDeclContext()->isRecord()) 1340 return BuildAnonymousStructOrUnion(S, DS, Record); 1341 1342 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1343 << DS.getSourceRange(); 1344 } 1345 1346 // Microsoft allows unnamed struct/union fields. Don't complain 1347 // about them. 1348 // FIXME: Should we support Microsoft's extensions in this area? 1349 if (Record->getDeclName() && getLangOptions().Microsoft) 1350 return DeclPtrTy::make(Tag); 1351 } 1352 1353 if (!DS.isMissingDeclaratorOk() && 1354 DS.getTypeSpecType() != DeclSpec::TST_error) { 1355 // Warn about typedefs of enums without names, since this is an 1356 // extension in both Microsoft an GNU. 1357 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1358 Tag && isa<EnumDecl>(Tag)) { 1359 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1360 << DS.getSourceRange(); 1361 return DeclPtrTy::make(Tag); 1362 } 1363 1364 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1365 << DS.getSourceRange(); 1366 return DeclPtrTy(); 1367 } 1368 1369 return DeclPtrTy::make(Tag); 1370} 1371 1372/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1373/// anonymous struct or union AnonRecord into the owning context Owner 1374/// and scope S. This routine will be invoked just after we realize 1375/// that an unnamed union or struct is actually an anonymous union or 1376/// struct, e.g., 1377/// 1378/// @code 1379/// union { 1380/// int i; 1381/// float f; 1382/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1383/// // f into the surrounding scope.x 1384/// @endcode 1385/// 1386/// This routine is recursive, injecting the names of nested anonymous 1387/// structs/unions into the owning context and scope as well. 1388bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1389 RecordDecl *AnonRecord) { 1390 bool Invalid = false; 1391 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1392 FEnd = AnonRecord->field_end(); 1393 F != FEnd; ++F) { 1394 if ((*F)->getDeclName()) { 1395 LookupResult R; 1396 LookupQualifiedName(R, Owner, (*F)->getDeclName(), 1397 LookupOrdinaryName, true); 1398 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1399 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1400 // C++ [class.union]p2: 1401 // The names of the members of an anonymous union shall be 1402 // distinct from the names of any other entity in the 1403 // scope in which the anonymous union is declared. 1404 unsigned diagKind 1405 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1406 : diag::err_anonymous_struct_member_redecl; 1407 Diag((*F)->getLocation(), diagKind) 1408 << (*F)->getDeclName(); 1409 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1410 Invalid = true; 1411 } else { 1412 // C++ [class.union]p2: 1413 // For the purpose of name lookup, after the anonymous union 1414 // definition, the members of the anonymous union are 1415 // considered to have been defined in the scope in which the 1416 // anonymous union is declared. 1417 Owner->makeDeclVisibleInContext(*F); 1418 S->AddDecl(DeclPtrTy::make(*F)); 1419 IdResolver.AddDecl(*F); 1420 } 1421 } else if (const RecordType *InnerRecordType 1422 = (*F)->getType()->getAs<RecordType>()) { 1423 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1424 if (InnerRecord->isAnonymousStructOrUnion()) 1425 Invalid = Invalid || 1426 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1427 } 1428 } 1429 1430 return Invalid; 1431} 1432 1433/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1434/// anonymous structure or union. Anonymous unions are a C++ feature 1435/// (C++ [class.union]) and a GNU C extension; anonymous structures 1436/// are a GNU C and GNU C++ extension. 1437Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1438 RecordDecl *Record) { 1439 DeclContext *Owner = Record->getDeclContext(); 1440 1441 // Diagnose whether this anonymous struct/union is an extension. 1442 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1443 Diag(Record->getLocation(), diag::ext_anonymous_union); 1444 else if (!Record->isUnion()) 1445 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1446 1447 // C and C++ require different kinds of checks for anonymous 1448 // structs/unions. 1449 bool Invalid = false; 1450 if (getLangOptions().CPlusPlus) { 1451 const char* PrevSpec = 0; 1452 unsigned DiagID; 1453 // C++ [class.union]p3: 1454 // Anonymous unions declared in a named namespace or in the 1455 // global namespace shall be declared static. 1456 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1457 (isa<TranslationUnitDecl>(Owner) || 1458 (isa<NamespaceDecl>(Owner) && 1459 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1460 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1461 Invalid = true; 1462 1463 // Recover by adding 'static'. 1464 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1465 PrevSpec, DiagID); 1466 } 1467 // C++ [class.union]p3: 1468 // A storage class is not allowed in a declaration of an 1469 // anonymous union in a class scope. 1470 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1471 isa<RecordDecl>(Owner)) { 1472 Diag(DS.getStorageClassSpecLoc(), 1473 diag::err_anonymous_union_with_storage_spec); 1474 Invalid = true; 1475 1476 // Recover by removing the storage specifier. 1477 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1478 PrevSpec, DiagID); 1479 } 1480 1481 // C++ [class.union]p2: 1482 // The member-specification of an anonymous union shall only 1483 // define non-static data members. [Note: nested types and 1484 // functions cannot be declared within an anonymous union. ] 1485 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1486 MemEnd = Record->decls_end(); 1487 Mem != MemEnd; ++Mem) { 1488 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1489 // C++ [class.union]p3: 1490 // An anonymous union shall not have private or protected 1491 // members (clause 11). 1492 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1493 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1494 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1495 Invalid = true; 1496 } 1497 } else if ((*Mem)->isImplicit()) { 1498 // Any implicit members are fine. 1499 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1500 // This is a type that showed up in an 1501 // elaborated-type-specifier inside the anonymous struct or 1502 // union, but which actually declares a type outside of the 1503 // anonymous struct or union. It's okay. 1504 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1505 if (!MemRecord->isAnonymousStructOrUnion() && 1506 MemRecord->getDeclName()) { 1507 // This is a nested type declaration. 1508 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1509 << (int)Record->isUnion(); 1510 Invalid = true; 1511 } 1512 } else { 1513 // We have something that isn't a non-static data 1514 // member. Complain about it. 1515 unsigned DK = diag::err_anonymous_record_bad_member; 1516 if (isa<TypeDecl>(*Mem)) 1517 DK = diag::err_anonymous_record_with_type; 1518 else if (isa<FunctionDecl>(*Mem)) 1519 DK = diag::err_anonymous_record_with_function; 1520 else if (isa<VarDecl>(*Mem)) 1521 DK = diag::err_anonymous_record_with_static; 1522 Diag((*Mem)->getLocation(), DK) 1523 << (int)Record->isUnion(); 1524 Invalid = true; 1525 } 1526 } 1527 } 1528 1529 if (!Record->isUnion() && !Owner->isRecord()) { 1530 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1531 << (int)getLangOptions().CPlusPlus; 1532 Invalid = true; 1533 } 1534 1535 // Mock up a declarator. 1536 Declarator Dc(DS, Declarator::TypeNameContext); 1537 DeclaratorInfo *DInfo = 0; 1538 GetTypeForDeclarator(Dc, S, &DInfo); 1539 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1540 1541 // Create a declaration for this anonymous struct/union. 1542 NamedDecl *Anon = 0; 1543 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1544 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1545 /*IdentifierInfo=*/0, 1546 Context.getTypeDeclType(Record), 1547 DInfo, 1548 /*BitWidth=*/0, /*Mutable=*/false); 1549 Anon->setAccess(AS_public); 1550 if (getLangOptions().CPlusPlus) 1551 FieldCollector->Add(cast<FieldDecl>(Anon)); 1552 } else { 1553 VarDecl::StorageClass SC; 1554 switch (DS.getStorageClassSpec()) { 1555 default: assert(0 && "Unknown storage class!"); 1556 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1557 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1558 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1559 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1560 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1561 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1562 case DeclSpec::SCS_mutable: 1563 // mutable can only appear on non-static class members, so it's always 1564 // an error here 1565 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1566 Invalid = true; 1567 SC = VarDecl::None; 1568 break; 1569 } 1570 1571 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1572 /*IdentifierInfo=*/0, 1573 Context.getTypeDeclType(Record), 1574 DInfo, 1575 SC); 1576 } 1577 Anon->setImplicit(); 1578 1579 // Add the anonymous struct/union object to the current 1580 // context. We'll be referencing this object when we refer to one of 1581 // its members. 1582 Owner->addDecl(Anon); 1583 1584 // Inject the members of the anonymous struct/union into the owning 1585 // context and into the identifier resolver chain for name lookup 1586 // purposes. 1587 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1588 Invalid = true; 1589 1590 // Mark this as an anonymous struct/union type. Note that we do not 1591 // do this until after we have already checked and injected the 1592 // members of this anonymous struct/union type, because otherwise 1593 // the members could be injected twice: once by DeclContext when it 1594 // builds its lookup table, and once by 1595 // InjectAnonymousStructOrUnionMembers. 1596 Record->setAnonymousStructOrUnion(true); 1597 1598 if (Invalid) 1599 Anon->setInvalidDecl(); 1600 1601 return DeclPtrTy::make(Anon); 1602} 1603 1604 1605/// GetNameForDeclarator - Determine the full declaration name for the 1606/// given Declarator. 1607DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1608 switch (D.getKind()) { 1609 case Declarator::DK_Abstract: 1610 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1611 return DeclarationName(); 1612 1613 case Declarator::DK_Normal: 1614 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1615 return DeclarationName(D.getIdentifier()); 1616 1617 case Declarator::DK_Constructor: { 1618 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1619 return Context.DeclarationNames.getCXXConstructorName( 1620 Context.getCanonicalType(Ty)); 1621 } 1622 1623 case Declarator::DK_Destructor: { 1624 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1625 return Context.DeclarationNames.getCXXDestructorName( 1626 Context.getCanonicalType(Ty)); 1627 } 1628 1629 case Declarator::DK_Conversion: { 1630 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1631 QualType Ty = GetTypeFromParser(D.getDeclaratorIdType()); 1632 return Context.DeclarationNames.getCXXConversionFunctionName( 1633 Context.getCanonicalType(Ty)); 1634 } 1635 1636 case Declarator::DK_Operator: 1637 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1638 return Context.DeclarationNames.getCXXOperatorName( 1639 D.getOverloadedOperator()); 1640 1641 case Declarator::DK_TemplateId: { 1642 TemplateName Name 1643 = TemplateName::getFromVoidPointer(D.getTemplateId()->Template); 1644 if (TemplateDecl *Template = Name.getAsTemplateDecl()) 1645 return Template->getDeclName(); 1646 if (OverloadedFunctionDecl *Ovl = Name.getAsOverloadedFunctionDecl()) 1647 return Ovl->getDeclName(); 1648 1649 return DeclarationName(); 1650 } 1651 } 1652 1653 assert(false && "Unknown name kind"); 1654 return DeclarationName(); 1655} 1656 1657/// isNearlyMatchingFunction - Determine whether the C++ functions 1658/// Declaration and Definition are "nearly" matching. This heuristic 1659/// is used to improve diagnostics in the case where an out-of-line 1660/// function definition doesn't match any declaration within 1661/// the class or namespace. 1662static bool isNearlyMatchingFunction(ASTContext &Context, 1663 FunctionDecl *Declaration, 1664 FunctionDecl *Definition) { 1665 if (Declaration->param_size() != Definition->param_size()) 1666 return false; 1667 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1668 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1669 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1670 1671 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1672 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1673 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1674 return false; 1675 } 1676 1677 return true; 1678} 1679 1680Sema::DeclPtrTy 1681Sema::HandleDeclarator(Scope *S, Declarator &D, 1682 MultiTemplateParamsArg TemplateParamLists, 1683 bool IsFunctionDefinition) { 1684 DeclarationName Name = GetNameForDeclarator(D); 1685 1686 // All of these full declarators require an identifier. If it doesn't have 1687 // one, the ParsedFreeStandingDeclSpec action should be used. 1688 if (!Name) { 1689 if (!D.isInvalidType()) // Reject this if we think it is valid. 1690 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1691 diag::err_declarator_need_ident) 1692 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1693 return DeclPtrTy(); 1694 } 1695 1696 // The scope passed in may not be a decl scope. Zip up the scope tree until 1697 // we find one that is. 1698 while ((S->getFlags() & Scope::DeclScope) == 0 || 1699 (S->getFlags() & Scope::TemplateParamScope) != 0) 1700 S = S->getParent(); 1701 1702 // If this is an out-of-line definition of a member of a class template 1703 // or class template partial specialization, we may need to rebuild the 1704 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1705 // for more information. 1706 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1707 // handle expressions properly. 1708 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1709 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1710 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1711 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1712 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1713 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1714 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1715 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1716 // FIXME: Preserve type source info. 1717 QualType T = GetTypeFromParser(DS.getTypeRep()); 1718 EnterDeclaratorContext(S, DC); 1719 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1720 ExitDeclaratorContext(S); 1721 if (T.isNull()) 1722 return DeclPtrTy(); 1723 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1724 } 1725 } 1726 1727 DeclContext *DC; 1728 NamedDecl *PrevDecl; 1729 NamedDecl *New; 1730 1731 DeclaratorInfo *DInfo = 0; 1732 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1733 1734 // See if this is a redefinition of a variable in the same scope. 1735 if (D.getCXXScopeSpec().isInvalid()) { 1736 DC = CurContext; 1737 PrevDecl = 0; 1738 D.setInvalidType(); 1739 } else if (!D.getCXXScopeSpec().isSet()) { 1740 LookupNameKind NameKind = LookupOrdinaryName; 1741 1742 // If the declaration we're planning to build will be a function 1743 // or object with linkage, then look for another declaration with 1744 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1745 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1746 /* Do nothing*/; 1747 else if (R->isFunctionType()) { 1748 if (CurContext->isFunctionOrMethod() || 1749 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1750 NameKind = LookupRedeclarationWithLinkage; 1751 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1752 NameKind = LookupRedeclarationWithLinkage; 1753 else if (CurContext->getLookupContext()->isTranslationUnit() && 1754 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1755 NameKind = LookupRedeclarationWithLinkage; 1756 1757 DC = CurContext; 1758 LookupResult R; 1759 LookupName(R, S, Name, NameKind, true, 1760 NameKind == LookupRedeclarationWithLinkage, 1761 D.getIdentifierLoc()); 1762 PrevDecl = R.getAsSingleDecl(Context); 1763 } else { // Something like "int foo::x;" 1764 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1765 1766 if (!DC) { 1767 // If we could not compute the declaration context, it's because the 1768 // declaration context is dependent but does not refer to a class, 1769 // class template, or class template partial specialization. Complain 1770 // and return early, to avoid the coming semantic disaster. 1771 Diag(D.getIdentifierLoc(), 1772 diag::err_template_qualified_declarator_no_match) 1773 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1774 << D.getCXXScopeSpec().getRange(); 1775 return DeclPtrTy(); 1776 } 1777 1778 if (!DC->isDependentContext() && 1779 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1780 return DeclPtrTy(); 1781 1782 LookupResult Res; 1783 LookupQualifiedName(Res, DC, Name, LookupOrdinaryName, true); 1784 PrevDecl = Res.getAsSingleDecl(Context); 1785 1786 // C++ 7.3.1.2p2: 1787 // Members (including explicit specializations of templates) of a named 1788 // namespace can also be defined outside that namespace by explicit 1789 // qualification of the name being defined, provided that the entity being 1790 // defined was already declared in the namespace and the definition appears 1791 // after the point of declaration in a namespace that encloses the 1792 // declarations namespace. 1793 // 1794 // Note that we only check the context at this point. We don't yet 1795 // have enough information to make sure that PrevDecl is actually 1796 // the declaration we want to match. For example, given: 1797 // 1798 // class X { 1799 // void f(); 1800 // void f(float); 1801 // }; 1802 // 1803 // void X::f(int) { } // ill-formed 1804 // 1805 // In this case, PrevDecl will point to the overload set 1806 // containing the two f's declared in X, but neither of them 1807 // matches. 1808 1809 // First check whether we named the global scope. 1810 if (isa<TranslationUnitDecl>(DC)) { 1811 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1812 << Name << D.getCXXScopeSpec().getRange(); 1813 } else if (!CurContext->Encloses(DC)) { 1814 // The qualifying scope doesn't enclose the original declaration. 1815 // Emit diagnostic based on current scope. 1816 SourceLocation L = D.getIdentifierLoc(); 1817 SourceRange R = D.getCXXScopeSpec().getRange(); 1818 if (isa<FunctionDecl>(CurContext)) 1819 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1820 else 1821 Diag(L, diag::err_invalid_declarator_scope) 1822 << Name << cast<NamedDecl>(DC) << R; 1823 D.setInvalidType(); 1824 } 1825 } 1826 1827 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1828 // Maybe we will complain about the shadowed template parameter. 1829 if (!D.isInvalidType()) 1830 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1831 D.setInvalidType(); 1832 1833 // Just pretend that we didn't see the previous declaration. 1834 PrevDecl = 0; 1835 } 1836 1837 // In C++, the previous declaration we find might be a tag type 1838 // (class or enum). In this case, the new declaration will hide the 1839 // tag type. Note that this does does not apply if we're declaring a 1840 // typedef (C++ [dcl.typedef]p4). 1841 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1842 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1843 PrevDecl = 0; 1844 1845 bool Redeclaration = false; 1846 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1847 if (TemplateParamLists.size()) { 1848 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1849 return DeclPtrTy(); 1850 } 1851 1852 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1853 } else if (R->isFunctionType()) { 1854 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1855 move(TemplateParamLists), 1856 IsFunctionDefinition, Redeclaration); 1857 } else { 1858 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1859 move(TemplateParamLists), 1860 Redeclaration); 1861 } 1862 1863 if (New == 0) 1864 return DeclPtrTy(); 1865 1866 // If this has an identifier and is not an invalid redeclaration or 1867 // function template specialization, add it to the scope stack. 1868 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1869 !(isa<FunctionDecl>(New) && 1870 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1871 PushOnScopeChains(New, S); 1872 1873 return DeclPtrTy::make(New); 1874} 1875 1876/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1877/// types into constant array types in certain situations which would otherwise 1878/// be errors (for GCC compatibility). 1879static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1880 ASTContext &Context, 1881 bool &SizeIsNegative) { 1882 // This method tries to turn a variable array into a constant 1883 // array even when the size isn't an ICE. This is necessary 1884 // for compatibility with code that depends on gcc's buggy 1885 // constant expression folding, like struct {char x[(int)(char*)2];} 1886 SizeIsNegative = false; 1887 1888 QualifierCollector Qs; 1889 const Type *Ty = Qs.strip(T); 1890 1891 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1892 QualType Pointee = PTy->getPointeeType(); 1893 QualType FixedType = 1894 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1895 if (FixedType.isNull()) return FixedType; 1896 FixedType = Context.getPointerType(FixedType); 1897 return Qs.apply(FixedType); 1898 } 1899 1900 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1901 if (!VLATy) 1902 return QualType(); 1903 // FIXME: We should probably handle this case 1904 if (VLATy->getElementType()->isVariablyModifiedType()) 1905 return QualType(); 1906 1907 Expr::EvalResult EvalResult; 1908 if (!VLATy->getSizeExpr() || 1909 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1910 !EvalResult.Val.isInt()) 1911 return QualType(); 1912 1913 llvm::APSInt &Res = EvalResult.Val.getInt(); 1914 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1915 // TODO: preserve the size expression in declarator info 1916 return Context.getConstantArrayType(VLATy->getElementType(), 1917 Res, ArrayType::Normal, 0); 1918 } 1919 1920 SizeIsNegative = true; 1921 return QualType(); 1922} 1923 1924/// \brief Register the given locally-scoped external C declaration so 1925/// that it can be found later for redeclarations 1926void 1927Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1928 Scope *S) { 1929 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1930 "Decl is not a locally-scoped decl!"); 1931 // Note that we have a locally-scoped external with this name. 1932 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1933 1934 if (!PrevDecl) 1935 return; 1936 1937 // If there was a previous declaration of this variable, it may be 1938 // in our identifier chain. Update the identifier chain with the new 1939 // declaration. 1940 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1941 // The previous declaration was found on the identifer resolver 1942 // chain, so remove it from its scope. 1943 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1944 S = S->getParent(); 1945 1946 if (S) 1947 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1948 } 1949} 1950 1951/// \brief Diagnose function specifiers on a declaration of an identifier that 1952/// does not identify a function. 1953void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1954 // FIXME: We should probably indicate the identifier in question to avoid 1955 // confusion for constructs like "inline int a(), b;" 1956 if (D.getDeclSpec().isInlineSpecified()) 1957 Diag(D.getDeclSpec().getInlineSpecLoc(), 1958 diag::err_inline_non_function); 1959 1960 if (D.getDeclSpec().isVirtualSpecified()) 1961 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1962 diag::err_virtual_non_function); 1963 1964 if (D.getDeclSpec().isExplicitSpecified()) 1965 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1966 diag::err_explicit_non_function); 1967} 1968 1969NamedDecl* 1970Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1971 QualType R, DeclaratorInfo *DInfo, 1972 NamedDecl* PrevDecl, bool &Redeclaration) { 1973 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1974 if (D.getCXXScopeSpec().isSet()) { 1975 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1976 << D.getCXXScopeSpec().getRange(); 1977 D.setInvalidType(); 1978 // Pretend we didn't see the scope specifier. 1979 DC = 0; 1980 } 1981 1982 if (getLangOptions().CPlusPlus) { 1983 // Check that there are no default arguments (C++ only). 1984 CheckExtraCXXDefaultArguments(D); 1985 } 1986 1987 DiagnoseFunctionSpecifiers(D); 1988 1989 if (D.getDeclSpec().isThreadSpecified()) 1990 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1991 1992 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 1993 if (!NewTD) return 0; 1994 1995 // Handle attributes prior to checking for duplicates in MergeVarDecl 1996 ProcessDeclAttributes(S, NewTD, D); 1997 // Merge the decl with the existing one if appropriate. If the decl is 1998 // in an outer scope, it isn't the same thing. 1999 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2000 Redeclaration = true; 2001 MergeTypeDefDecl(NewTD, PrevDecl); 2002 } 2003 2004 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2005 // then it shall have block scope. 2006 QualType T = NewTD->getUnderlyingType(); 2007 if (T->isVariablyModifiedType()) { 2008 CurFunctionNeedsScopeChecking = true; 2009 2010 if (S->getFnParent() == 0) { 2011 bool SizeIsNegative; 2012 QualType FixedTy = 2013 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2014 if (!FixedTy.isNull()) { 2015 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2016 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2017 } else { 2018 if (SizeIsNegative) 2019 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2020 else if (T->isVariableArrayType()) 2021 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2022 else 2023 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2024 NewTD->setInvalidDecl(); 2025 } 2026 } 2027 } 2028 2029 // If this is the C FILE type, notify the AST context. 2030 if (IdentifierInfo *II = NewTD->getIdentifier()) 2031 if (!NewTD->isInvalidDecl() && 2032 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2033 if (II->isStr("FILE")) 2034 Context.setFILEDecl(NewTD); 2035 else if (II->isStr("jmp_buf")) 2036 Context.setjmp_bufDecl(NewTD); 2037 else if (II->isStr("sigjmp_buf")) 2038 Context.setsigjmp_bufDecl(NewTD); 2039 } 2040 2041 return NewTD; 2042} 2043 2044/// \brief Determines whether the given declaration is an out-of-scope 2045/// previous declaration. 2046/// 2047/// This routine should be invoked when name lookup has found a 2048/// previous declaration (PrevDecl) that is not in the scope where a 2049/// new declaration by the same name is being introduced. If the new 2050/// declaration occurs in a local scope, previous declarations with 2051/// linkage may still be considered previous declarations (C99 2052/// 6.2.2p4-5, C++ [basic.link]p6). 2053/// 2054/// \param PrevDecl the previous declaration found by name 2055/// lookup 2056/// 2057/// \param DC the context in which the new declaration is being 2058/// declared. 2059/// 2060/// \returns true if PrevDecl is an out-of-scope previous declaration 2061/// for a new delcaration with the same name. 2062static bool 2063isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2064 ASTContext &Context) { 2065 if (!PrevDecl) 2066 return 0; 2067 2068 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2069 // case we need to check each of the overloaded functions. 2070 if (!PrevDecl->hasLinkage()) 2071 return false; 2072 2073 if (Context.getLangOptions().CPlusPlus) { 2074 // C++ [basic.link]p6: 2075 // If there is a visible declaration of an entity with linkage 2076 // having the same name and type, ignoring entities declared 2077 // outside the innermost enclosing namespace scope, the block 2078 // scope declaration declares that same entity and receives the 2079 // linkage of the previous declaration. 2080 DeclContext *OuterContext = DC->getLookupContext(); 2081 if (!OuterContext->isFunctionOrMethod()) 2082 // This rule only applies to block-scope declarations. 2083 return false; 2084 else { 2085 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2086 if (PrevOuterContext->isRecord()) 2087 // We found a member function: ignore it. 2088 return false; 2089 else { 2090 // Find the innermost enclosing namespace for the new and 2091 // previous declarations. 2092 while (!OuterContext->isFileContext()) 2093 OuterContext = OuterContext->getParent(); 2094 while (!PrevOuterContext->isFileContext()) 2095 PrevOuterContext = PrevOuterContext->getParent(); 2096 2097 // The previous declaration is in a different namespace, so it 2098 // isn't the same function. 2099 if (OuterContext->getPrimaryContext() != 2100 PrevOuterContext->getPrimaryContext()) 2101 return false; 2102 } 2103 } 2104 } 2105 2106 return true; 2107} 2108 2109NamedDecl* 2110Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2111 QualType R, DeclaratorInfo *DInfo, 2112 NamedDecl* PrevDecl, 2113 MultiTemplateParamsArg TemplateParamLists, 2114 bool &Redeclaration) { 2115 DeclarationName Name = GetNameForDeclarator(D); 2116 2117 // Check that there are no default arguments (C++ only). 2118 if (getLangOptions().CPlusPlus) 2119 CheckExtraCXXDefaultArguments(D); 2120 2121 VarDecl *NewVD; 2122 VarDecl::StorageClass SC; 2123 switch (D.getDeclSpec().getStorageClassSpec()) { 2124 default: assert(0 && "Unknown storage class!"); 2125 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2126 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2127 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2128 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2129 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2130 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2131 case DeclSpec::SCS_mutable: 2132 // mutable can only appear on non-static class members, so it's always 2133 // an error here 2134 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2135 D.setInvalidType(); 2136 SC = VarDecl::None; 2137 break; 2138 } 2139 2140 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2141 if (!II) { 2142 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2143 << Name.getAsString(); 2144 return 0; 2145 } 2146 2147 DiagnoseFunctionSpecifiers(D); 2148 2149 if (!DC->isRecord() && S->getFnParent() == 0) { 2150 // C99 6.9p2: The storage-class specifiers auto and register shall not 2151 // appear in the declaration specifiers in an external declaration. 2152 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2153 2154 // If this is a register variable with an asm label specified, then this 2155 // is a GNU extension. 2156 if (SC == VarDecl::Register && D.getAsmLabel()) 2157 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2158 else 2159 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2160 D.setInvalidType(); 2161 } 2162 } 2163 if (DC->isRecord() && !CurContext->isRecord()) { 2164 // This is an out-of-line definition of a static data member. 2165 if (SC == VarDecl::Static) { 2166 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2167 diag::err_static_out_of_line) 2168 << CodeModificationHint::CreateRemoval( 2169 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2170 } else if (SC == VarDecl::None) 2171 SC = VarDecl::Static; 2172 } 2173 if (SC == VarDecl::Static) { 2174 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2175 if (RD->isLocalClass()) 2176 Diag(D.getIdentifierLoc(), 2177 diag::err_static_data_member_not_allowed_in_local_class) 2178 << Name << RD->getDeclName(); 2179 } 2180 } 2181 2182 // Match up the template parameter lists with the scope specifier, then 2183 // determine whether we have a template or a template specialization. 2184 bool isExplicitSpecialization = false; 2185 if (TemplateParameterList *TemplateParams 2186 = MatchTemplateParametersToScopeSpecifier( 2187 D.getDeclSpec().getSourceRange().getBegin(), 2188 D.getCXXScopeSpec(), 2189 (TemplateParameterList**)TemplateParamLists.get(), 2190 TemplateParamLists.size(), 2191 isExplicitSpecialization)) { 2192 if (TemplateParams->size() > 0) { 2193 // There is no such thing as a variable template. 2194 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2195 << II 2196 << SourceRange(TemplateParams->getTemplateLoc(), 2197 TemplateParams->getRAngleLoc()); 2198 return 0; 2199 } else { 2200 // There is an extraneous 'template<>' for this variable. Complain 2201 // about it, but allow the declaration of the variable. 2202 Diag(TemplateParams->getTemplateLoc(), 2203 diag::err_template_variable_noparams) 2204 << II 2205 << SourceRange(TemplateParams->getTemplateLoc(), 2206 TemplateParams->getRAngleLoc()); 2207 2208 isExplicitSpecialization = true; 2209 } 2210 } 2211 2212 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2213 II, R, DInfo, SC); 2214 2215 if (D.isInvalidType()) 2216 NewVD->setInvalidDecl(); 2217 2218 if (D.getDeclSpec().isThreadSpecified()) { 2219 if (NewVD->hasLocalStorage()) 2220 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2221 else if (!Context.Target.isTLSSupported()) 2222 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2223 else 2224 NewVD->setThreadSpecified(true); 2225 } 2226 2227 // Set the lexical context. If the declarator has a C++ scope specifier, the 2228 // lexical context will be different from the semantic context. 2229 NewVD->setLexicalDeclContext(CurContext); 2230 2231 // Handle attributes prior to checking for duplicates in MergeVarDecl 2232 ProcessDeclAttributes(S, NewVD, D); 2233 2234 // Handle GNU asm-label extension (encoded as an attribute). 2235 if (Expr *E = (Expr*) D.getAsmLabel()) { 2236 // The parser guarantees this is a string. 2237 StringLiteral *SE = cast<StringLiteral>(E); 2238 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2239 SE->getByteLength()))); 2240 } 2241 2242 // If name lookup finds a previous declaration that is not in the 2243 // same scope as the new declaration, this may still be an 2244 // acceptable redeclaration. 2245 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2246 !(NewVD->hasLinkage() && 2247 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2248 PrevDecl = 0; 2249 2250 // Merge the decl with the existing one if appropriate. 2251 if (PrevDecl) { 2252 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2253 // The user tried to define a non-static data member 2254 // out-of-line (C++ [dcl.meaning]p1). 2255 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2256 << D.getCXXScopeSpec().getRange(); 2257 PrevDecl = 0; 2258 NewVD->setInvalidDecl(); 2259 } 2260 } else if (D.getCXXScopeSpec().isSet()) { 2261 // No previous declaration in the qualifying scope. 2262 Diag(D.getIdentifierLoc(), diag::err_no_member) 2263 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2264 << D.getCXXScopeSpec().getRange(); 2265 NewVD->setInvalidDecl(); 2266 } 2267 2268 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2269 2270 // This is an explicit specialization of a static data member. Check it. 2271 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2272 CheckMemberSpecialization(NewVD, PrevDecl)) 2273 NewVD->setInvalidDecl(); 2274 2275 // attributes declared post-definition are currently ignored 2276 if (PrevDecl) { 2277 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2278 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2279 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2280 Diag(Def->getLocation(), diag::note_previous_definition); 2281 } 2282 } 2283 2284 // If this is a locally-scoped extern C variable, update the map of 2285 // such variables. 2286 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2287 !NewVD->isInvalidDecl()) 2288 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2289 2290 return NewVD; 2291} 2292 2293/// \brief Perform semantic checking on a newly-created variable 2294/// declaration. 2295/// 2296/// This routine performs all of the type-checking required for a 2297/// variable declaration once it has been built. It is used both to 2298/// check variables after they have been parsed and their declarators 2299/// have been translated into a declaration, and to check variables 2300/// that have been instantiated from a template. 2301/// 2302/// Sets NewVD->isInvalidDecl() if an error was encountered. 2303void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2304 bool &Redeclaration) { 2305 // If the decl is already known invalid, don't check it. 2306 if (NewVD->isInvalidDecl()) 2307 return; 2308 2309 QualType T = NewVD->getType(); 2310 2311 if (T->isObjCInterfaceType()) { 2312 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2313 return NewVD->setInvalidDecl(); 2314 } 2315 2316 // The variable can not have an abstract class type. 2317 if (RequireNonAbstractType(NewVD->getLocation(), T, 2318 diag::err_abstract_type_in_decl, 2319 AbstractVariableType)) 2320 return NewVD->setInvalidDecl(); 2321 2322 // Emit an error if an address space was applied to decl with local storage. 2323 // This includes arrays of objects with address space qualifiers, but not 2324 // automatic variables that point to other address spaces. 2325 // ISO/IEC TR 18037 S5.1.2 2326 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2327 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2328 return NewVD->setInvalidDecl(); 2329 } 2330 2331 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2332 && !NewVD->hasAttr<BlocksAttr>()) 2333 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2334 2335 bool isVM = T->isVariablyModifiedType(); 2336 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2337 NewVD->hasAttr<BlocksAttr>()) 2338 CurFunctionNeedsScopeChecking = true; 2339 2340 if ((isVM && NewVD->hasLinkage()) || 2341 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2342 bool SizeIsNegative; 2343 QualType FixedTy = 2344 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2345 2346 if (FixedTy.isNull() && T->isVariableArrayType()) { 2347 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2348 // FIXME: This won't give the correct result for 2349 // int a[10][n]; 2350 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2351 2352 if (NewVD->isFileVarDecl()) 2353 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2354 << SizeRange; 2355 else if (NewVD->getStorageClass() == VarDecl::Static) 2356 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2357 << SizeRange; 2358 else 2359 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2360 << SizeRange; 2361 return NewVD->setInvalidDecl(); 2362 } 2363 2364 if (FixedTy.isNull()) { 2365 if (NewVD->isFileVarDecl()) 2366 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2367 else 2368 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2369 return NewVD->setInvalidDecl(); 2370 } 2371 2372 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2373 NewVD->setType(FixedTy); 2374 } 2375 2376 if (!PrevDecl && NewVD->isExternC()) { 2377 // Since we did not find anything by this name and we're declaring 2378 // an extern "C" variable, look for a non-visible extern "C" 2379 // declaration with the same name. 2380 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2381 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2382 if (Pos != LocallyScopedExternalDecls.end()) 2383 PrevDecl = Pos->second; 2384 } 2385 2386 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2387 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2388 << T; 2389 return NewVD->setInvalidDecl(); 2390 } 2391 2392 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2393 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2394 return NewVD->setInvalidDecl(); 2395 } 2396 2397 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2398 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2399 return NewVD->setInvalidDecl(); 2400 } 2401 2402 if (PrevDecl) { 2403 Redeclaration = true; 2404 MergeVarDecl(NewVD, PrevDecl); 2405 } 2406} 2407 2408static bool isUsingDecl(Decl *D) { 2409 return isa<UsingDecl>(D) || isa<UnresolvedUsingDecl>(D); 2410} 2411 2412/// \brief Data used with FindOverriddenMethod 2413struct FindOverriddenMethodData { 2414 Sema *S; 2415 CXXMethodDecl *Method; 2416}; 2417 2418/// \brief Member lookup function that determines whether a given C++ 2419/// method overrides a method in a base class, to be used with 2420/// CXXRecordDecl::lookupInBases(). 2421static bool FindOverriddenMethod(CXXBaseSpecifier *Specifier, 2422 CXXBasePath &Path, 2423 void *UserData) { 2424 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2425 2426 FindOverriddenMethodData *Data 2427 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2428 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2429 Path.Decls.first != Path.Decls.second; 2430 ++Path.Decls.first) { 2431 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2432 OverloadedFunctionDecl::function_iterator MatchedDecl; 2433 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2434 return true; 2435 } 2436 } 2437 2438 return false; 2439} 2440 2441NamedDecl* 2442Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2443 QualType R, DeclaratorInfo *DInfo, 2444 NamedDecl* PrevDecl, 2445 MultiTemplateParamsArg TemplateParamLists, 2446 bool IsFunctionDefinition, bool &Redeclaration) { 2447 assert(R.getTypePtr()->isFunctionType()); 2448 2449 DeclarationName Name = GetNameForDeclarator(D); 2450 FunctionDecl::StorageClass SC = FunctionDecl::None; 2451 switch (D.getDeclSpec().getStorageClassSpec()) { 2452 default: assert(0 && "Unknown storage class!"); 2453 case DeclSpec::SCS_auto: 2454 case DeclSpec::SCS_register: 2455 case DeclSpec::SCS_mutable: 2456 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2457 diag::err_typecheck_sclass_func); 2458 D.setInvalidType(); 2459 break; 2460 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2461 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2462 case DeclSpec::SCS_static: { 2463 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2464 // C99 6.7.1p5: 2465 // The declaration of an identifier for a function that has 2466 // block scope shall have no explicit storage-class specifier 2467 // other than extern 2468 // See also (C++ [dcl.stc]p4). 2469 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2470 diag::err_static_block_func); 2471 SC = FunctionDecl::None; 2472 } else 2473 SC = FunctionDecl::Static; 2474 break; 2475 } 2476 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2477 } 2478 2479 if (D.getDeclSpec().isThreadSpecified()) 2480 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2481 2482 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2483 bool isInline = D.getDeclSpec().isInlineSpecified(); 2484 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2485 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2486 2487 // Check that the return type is not an abstract class type. 2488 // For record types, this is done by the AbstractClassUsageDiagnoser once 2489 // the class has been completely parsed. 2490 if (!DC->isRecord() && 2491 RequireNonAbstractType(D.getIdentifierLoc(), 2492 R->getAs<FunctionType>()->getResultType(), 2493 diag::err_abstract_type_in_decl, 2494 AbstractReturnType)) 2495 D.setInvalidType(); 2496 2497 // Do not allow returning a objc interface by-value. 2498 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2499 Diag(D.getIdentifierLoc(), 2500 diag::err_object_cannot_be_passed_returned_by_value) << 0 2501 << R->getAs<FunctionType>()->getResultType(); 2502 D.setInvalidType(); 2503 } 2504 2505 bool isVirtualOkay = false; 2506 FunctionDecl *NewFD; 2507 2508 if (isFriend) { 2509 // DC is the namespace in which the function is being declared. 2510 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2511 "friend function being created in a non-namespace context"); 2512 2513 // C++ [class.friend]p5 2514 // A function can be defined in a friend declaration of a 2515 // class . . . . Such a function is implicitly inline. 2516 isInline |= IsFunctionDefinition; 2517 } 2518 2519 if (D.getKind() == Declarator::DK_Constructor) { 2520 // This is a C++ constructor declaration. 2521 assert(DC->isRecord() && 2522 "Constructors can only be declared in a member context"); 2523 2524 R = CheckConstructorDeclarator(D, R, SC); 2525 2526 // Create the new declaration 2527 NewFD = CXXConstructorDecl::Create(Context, 2528 cast<CXXRecordDecl>(DC), 2529 D.getIdentifierLoc(), Name, R, DInfo, 2530 isExplicit, isInline, 2531 /*isImplicitlyDeclared=*/false); 2532 } else if (D.getKind() == Declarator::DK_Destructor) { 2533 // This is a C++ destructor declaration. 2534 if (DC->isRecord()) { 2535 R = CheckDestructorDeclarator(D, SC); 2536 2537 NewFD = CXXDestructorDecl::Create(Context, 2538 cast<CXXRecordDecl>(DC), 2539 D.getIdentifierLoc(), Name, R, 2540 isInline, 2541 /*isImplicitlyDeclared=*/false); 2542 2543 isVirtualOkay = true; 2544 } else { 2545 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2546 2547 // Create a FunctionDecl to satisfy the function definition parsing 2548 // code path. 2549 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2550 Name, R, DInfo, SC, isInline, 2551 /*hasPrototype=*/true); 2552 D.setInvalidType(); 2553 } 2554 } else if (D.getKind() == Declarator::DK_Conversion) { 2555 if (!DC->isRecord()) { 2556 Diag(D.getIdentifierLoc(), 2557 diag::err_conv_function_not_member); 2558 return 0; 2559 } 2560 2561 CheckConversionDeclarator(D, R, SC); 2562 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2563 D.getIdentifierLoc(), Name, R, DInfo, 2564 isInline, isExplicit); 2565 2566 isVirtualOkay = true; 2567 } else if (DC->isRecord()) { 2568 // If the of the function is the same as the name of the record, then this 2569 // must be an invalid constructor that has a return type. 2570 // (The parser checks for a return type and makes the declarator a 2571 // constructor if it has no return type). 2572 // must have an invalid constructor that has a return type 2573 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2574 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2575 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2576 << SourceRange(D.getIdentifierLoc()); 2577 return 0; 2578 } 2579 2580 // This is a C++ method declaration. 2581 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2582 D.getIdentifierLoc(), Name, R, DInfo, 2583 (SC == FunctionDecl::Static), isInline); 2584 2585 isVirtualOkay = (SC != FunctionDecl::Static); 2586 } else { 2587 // Determine whether the function was written with a 2588 // prototype. This true when: 2589 // - we're in C++ (where every function has a prototype), 2590 // - there is a prototype in the declarator, or 2591 // - the type R of the function is some kind of typedef or other reference 2592 // to a type name (which eventually refers to a function type). 2593 bool HasPrototype = 2594 getLangOptions().CPlusPlus || 2595 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2596 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2597 2598 NewFD = FunctionDecl::Create(Context, DC, 2599 D.getIdentifierLoc(), 2600 Name, R, DInfo, SC, isInline, HasPrototype); 2601 } 2602 2603 if (D.isInvalidType()) 2604 NewFD->setInvalidDecl(); 2605 2606 // Set the lexical context. If the declarator has a C++ 2607 // scope specifier, or is the object of a friend declaration, the 2608 // lexical context will be different from the semantic context. 2609 NewFD->setLexicalDeclContext(CurContext); 2610 2611 // Match up the template parameter lists with the scope specifier, then 2612 // determine whether we have a template or a template specialization. 2613 FunctionTemplateDecl *FunctionTemplate = 0; 2614 bool isExplicitSpecialization = false; 2615 bool isFunctionTemplateSpecialization = false; 2616 if (TemplateParameterList *TemplateParams 2617 = MatchTemplateParametersToScopeSpecifier( 2618 D.getDeclSpec().getSourceRange().getBegin(), 2619 D.getCXXScopeSpec(), 2620 (TemplateParameterList**)TemplateParamLists.get(), 2621 TemplateParamLists.size(), 2622 isExplicitSpecialization)) { 2623 if (TemplateParams->size() > 0) { 2624 // This is a function template 2625 2626 // Check that we can declare a template here. 2627 if (CheckTemplateDeclScope(S, TemplateParams)) 2628 return 0; 2629 2630 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2631 NewFD->getLocation(), 2632 Name, TemplateParams, 2633 NewFD); 2634 FunctionTemplate->setLexicalDeclContext(CurContext); 2635 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2636 } else { 2637 // This is a function template specialization. 2638 isFunctionTemplateSpecialization = true; 2639 } 2640 2641 // FIXME: Free this memory properly. 2642 TemplateParamLists.release(); 2643 } 2644 2645 // C++ [dcl.fct.spec]p5: 2646 // The virtual specifier shall only be used in declarations of 2647 // nonstatic class member functions that appear within a 2648 // member-specification of a class declaration; see 10.3. 2649 // 2650 if (isVirtual && !NewFD->isInvalidDecl()) { 2651 if (!isVirtualOkay) { 2652 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2653 diag::err_virtual_non_function); 2654 } else if (!CurContext->isRecord()) { 2655 // 'virtual' was specified outside of the class. 2656 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2657 << CodeModificationHint::CreateRemoval( 2658 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2659 } else { 2660 // Okay: Add virtual to the method. 2661 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2662 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2663 CurClass->setAggregate(false); 2664 CurClass->setPOD(false); 2665 CurClass->setEmpty(false); 2666 CurClass->setPolymorphic(true); 2667 CurClass->setHasTrivialConstructor(false); 2668 CurClass->setHasTrivialCopyConstructor(false); 2669 CurClass->setHasTrivialCopyAssignment(false); 2670 } 2671 } 2672 2673 if (isFriend) { 2674 if (FunctionTemplate) { 2675 FunctionTemplate->setObjectOfFriendDecl( 2676 /* PreviouslyDeclared= */ PrevDecl != NULL); 2677 FunctionTemplate->setAccess(AS_public); 2678 } 2679 else 2680 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2681 2682 NewFD->setAccess(AS_public); 2683 } 2684 2685 2686 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2687 // Look for virtual methods in base classes that this method might override. 2688 CXXBasePaths Paths; 2689 FindOverriddenMethodData Data; 2690 Data.Method = NewMD; 2691 Data.S = this; 2692 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2693 Paths)) { 2694 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2695 E = Paths.found_decls_end(); I != E; ++I) { 2696 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2697 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2698 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2699 NewMD->addOverriddenMethod(OldMD); 2700 } 2701 } 2702 } 2703 } 2704 2705 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2706 !CurContext->isRecord()) { 2707 // C++ [class.static]p1: 2708 // A data or function member of a class may be declared static 2709 // in a class definition, in which case it is a static member of 2710 // the class. 2711 2712 // Complain about the 'static' specifier if it's on an out-of-line 2713 // member function definition. 2714 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2715 diag::err_static_out_of_line) 2716 << CodeModificationHint::CreateRemoval( 2717 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2718 } 2719 2720 // Handle GNU asm-label extension (encoded as an attribute). 2721 if (Expr *E = (Expr*) D.getAsmLabel()) { 2722 // The parser guarantees this is a string. 2723 StringLiteral *SE = cast<StringLiteral>(E); 2724 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2725 SE->getByteLength()))); 2726 } 2727 2728 // Copy the parameter declarations from the declarator D to the function 2729 // declaration NewFD, if they are available. First scavenge them into Params. 2730 llvm::SmallVector<ParmVarDecl*, 16> Params; 2731 if (D.getNumTypeObjects() > 0) { 2732 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2733 2734 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2735 // function that takes no arguments, not a function that takes a 2736 // single void argument. 2737 // We let through "const void" here because Sema::GetTypeForDeclarator 2738 // already checks for that case. 2739 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2740 FTI.ArgInfo[0].Param && 2741 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2742 // Empty arg list, don't push any params. 2743 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2744 2745 // In C++, the empty parameter-type-list must be spelled "void"; a 2746 // typedef of void is not permitted. 2747 if (getLangOptions().CPlusPlus && 2748 Param->getType().getUnqualifiedType() != Context.VoidTy) 2749 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2750 // FIXME: Leaks decl? 2751 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2752 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2753 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2754 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2755 Param->setDeclContext(NewFD); 2756 Params.push_back(Param); 2757 } 2758 } 2759 2760 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2761 // When we're declaring a function with a typedef, typeof, etc as in the 2762 // following example, we'll need to synthesize (unnamed) 2763 // parameters for use in the declaration. 2764 // 2765 // @code 2766 // typedef void fn(int); 2767 // fn f; 2768 // @endcode 2769 2770 // Synthesize a parameter for each argument type. 2771 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2772 AE = FT->arg_type_end(); AI != AE; ++AI) { 2773 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2774 SourceLocation(), 0, 2775 *AI, /*DInfo=*/0, 2776 VarDecl::None, 0); 2777 Param->setImplicit(); 2778 Params.push_back(Param); 2779 } 2780 } else { 2781 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2782 "Should not need args for typedef of non-prototype fn"); 2783 } 2784 // Finally, we know we have the right number of parameters, install them. 2785 NewFD->setParams(Context, Params.data(), Params.size()); 2786 2787 // If name lookup finds a previous declaration that is not in the 2788 // same scope as the new declaration, this may still be an 2789 // acceptable redeclaration. 2790 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2791 !(NewFD->hasLinkage() && 2792 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2793 PrevDecl = 0; 2794 2795 // If the declarator is a template-id, translate the parser's template 2796 // argument list into our AST format. 2797 bool HasExplicitTemplateArgs = false; 2798 llvm::SmallVector<TemplateArgument, 16> TemplateArgs; 2799 SourceLocation LAngleLoc, RAngleLoc; 2800 if (D.getKind() == Declarator::DK_TemplateId) { 2801 TemplateIdAnnotation *TemplateId = D.getTemplateId(); 2802 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2803 TemplateId->getTemplateArgs(), 2804 TemplateId->getTemplateArgIsType(), 2805 TemplateId->NumArgs); 2806 translateTemplateArguments(TemplateArgsPtr, 2807 TemplateId->getTemplateArgLocations(), 2808 TemplateArgs); 2809 TemplateArgsPtr.release(); 2810 2811 HasExplicitTemplateArgs = true; 2812 LAngleLoc = TemplateId->LAngleLoc; 2813 RAngleLoc = TemplateId->RAngleLoc; 2814 2815 if (FunctionTemplate) { 2816 // FIXME: Diagnose function template with explicit template 2817 // arguments. 2818 HasExplicitTemplateArgs = false; 2819 } else if (!isFunctionTemplateSpecialization && 2820 !D.getDeclSpec().isFriendSpecified()) { 2821 // We have encountered something that the user meant to be a 2822 // specialization (because it has explicitly-specified template 2823 // arguments) but that was not introduced with a "template<>" (or had 2824 // too few of them). 2825 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2826 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2827 << CodeModificationHint::CreateInsertion( 2828 D.getDeclSpec().getSourceRange().getBegin(), 2829 "template<> "); 2830 isFunctionTemplateSpecialization = true; 2831 } 2832 } 2833 2834 if (isFunctionTemplateSpecialization) { 2835 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2836 LAngleLoc, TemplateArgs.data(), 2837 TemplateArgs.size(), RAngleLoc, 2838 PrevDecl)) 2839 NewFD->setInvalidDecl(); 2840 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2841 CheckMemberSpecialization(NewFD, PrevDecl)) 2842 NewFD->setInvalidDecl(); 2843 2844 // Perform semantic checking on the function declaration. 2845 bool OverloadableAttrRequired = false; // FIXME: HACK! 2846 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2847 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2848 2849 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2850 // An out-of-line member function declaration must also be a 2851 // definition (C++ [dcl.meaning]p1). 2852 // Note that this is not the case for explicit specializations of 2853 // function templates or member functions of class templates, per 2854 // C++ [temp.expl.spec]p2. 2855 if (!IsFunctionDefinition && !isFriend && 2856 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2857 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2858 << D.getCXXScopeSpec().getRange(); 2859 NewFD->setInvalidDecl(); 2860 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2861 // The user tried to provide an out-of-line definition for a 2862 // function that is a member of a class or namespace, but there 2863 // was no such member function declared (C++ [class.mfct]p2, 2864 // C++ [namespace.memdef]p2). For example: 2865 // 2866 // class X { 2867 // void f() const; 2868 // }; 2869 // 2870 // void X::f() { } // ill-formed 2871 // 2872 // Complain about this problem, and attempt to suggest close 2873 // matches (e.g., those that differ only in cv-qualifiers and 2874 // whether the parameter types are references). 2875 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2876 << Name << DC << D.getCXXScopeSpec().getRange(); 2877 NewFD->setInvalidDecl(); 2878 2879 LookupResult Prev; 2880 LookupQualifiedName(Prev, DC, Name, LookupOrdinaryName, true); 2881 assert(!Prev.isAmbiguous() && 2882 "Cannot have an ambiguity in previous-declaration lookup"); 2883 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2884 Func != FuncEnd; ++Func) { 2885 if (isa<FunctionDecl>(*Func) && 2886 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2887 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2888 } 2889 2890 PrevDecl = 0; 2891 } 2892 } 2893 2894 // Handle attributes. We need to have merged decls when handling attributes 2895 // (for example to check for conflicts, etc). 2896 // FIXME: This needs to happen before we merge declarations. Then, 2897 // let attribute merging cope with attribute conflicts. 2898 ProcessDeclAttributes(S, NewFD, D); 2899 2900 // attributes declared post-definition are currently ignored 2901 if (Redeclaration && PrevDecl) { 2902 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2903 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2904 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2905 Diag(Def->getLocation(), diag::note_previous_definition); 2906 } 2907 } 2908 2909 AddKnownFunctionAttributes(NewFD); 2910 2911 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2912 // If a function name is overloadable in C, then every function 2913 // with that name must be marked "overloadable". 2914 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2915 << Redeclaration << NewFD; 2916 if (PrevDecl) 2917 Diag(PrevDecl->getLocation(), 2918 diag::note_attribute_overloadable_prev_overload); 2919 NewFD->addAttr(::new (Context) OverloadableAttr()); 2920 } 2921 2922 // If this is a locally-scoped extern C function, update the 2923 // map of such names. 2924 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2925 && !NewFD->isInvalidDecl()) 2926 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2927 2928 // Set this FunctionDecl's range up to the right paren. 2929 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2930 2931 if (FunctionTemplate && NewFD->isInvalidDecl()) 2932 FunctionTemplate->setInvalidDecl(); 2933 2934 if (FunctionTemplate) 2935 return FunctionTemplate; 2936 2937 return NewFD; 2938} 2939 2940/// \brief Perform semantic checking of a new function declaration. 2941/// 2942/// Performs semantic analysis of the new function declaration 2943/// NewFD. This routine performs all semantic checking that does not 2944/// require the actual declarator involved in the declaration, and is 2945/// used both for the declaration of functions as they are parsed 2946/// (called via ActOnDeclarator) and for the declaration of functions 2947/// that have been instantiated via C++ template instantiation (called 2948/// via InstantiateDecl). 2949/// 2950/// \param IsExplicitSpecialiation whether this new function declaration is 2951/// an explicit specialization of the previous declaration. 2952/// 2953/// This sets NewFD->isInvalidDecl() to true if there was an error. 2954void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2955 bool IsExplicitSpecialization, 2956 bool &Redeclaration, 2957 bool &OverloadableAttrRequired) { 2958 // If NewFD is already known erroneous, don't do any of this checking. 2959 if (NewFD->isInvalidDecl()) 2960 return; 2961 2962 if (NewFD->getResultType()->isVariablyModifiedType()) { 2963 // Functions returning a variably modified type violate C99 6.7.5.2p2 2964 // because all functions have linkage. 2965 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2966 return NewFD->setInvalidDecl(); 2967 } 2968 2969 if (NewFD->isMain()) 2970 CheckMain(NewFD); 2971 2972 // Check for a previous declaration of this name. 2973 if (!PrevDecl && NewFD->isExternC()) { 2974 // Since we did not find anything by this name and we're declaring 2975 // an extern "C" function, look for a non-visible extern "C" 2976 // declaration with the same name. 2977 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2978 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2979 if (Pos != LocallyScopedExternalDecls.end()) 2980 PrevDecl = Pos->second; 2981 } 2982 2983 // Merge or overload the declaration with an existing declaration of 2984 // the same name, if appropriate. 2985 if (PrevDecl) { 2986 // Determine whether NewFD is an overload of PrevDecl or 2987 // a declaration that requires merging. If it's an overload, 2988 // there's no more work to do here; we'll just add the new 2989 // function to the scope. 2990 OverloadedFunctionDecl::function_iterator MatchedDecl; 2991 2992 if (!getLangOptions().CPlusPlus && 2993 AllowOverloadingOfFunction(PrevDecl, Context)) { 2994 OverloadableAttrRequired = true; 2995 2996 // Functions marked "overloadable" must have a prototype (that 2997 // we can't get through declaration merging). 2998 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 2999 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3000 << NewFD; 3001 Redeclaration = true; 3002 3003 // Turn this into a variadic function with no parameters. 3004 QualType R = Context.getFunctionType( 3005 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3006 0, 0, true, 0); 3007 NewFD->setType(R); 3008 return NewFD->setInvalidDecl(); 3009 } 3010 } 3011 3012 if (PrevDecl && 3013 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3014 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3015 Redeclaration = true; 3016 Decl *OldDecl = PrevDecl; 3017 3018 // If PrevDecl was an overloaded function, extract the 3019 // FunctionDecl that matched. 3020 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3021 OldDecl = *MatchedDecl; 3022 3023 // NewFD and OldDecl represent declarations that need to be 3024 // merged. 3025 if (MergeFunctionDecl(NewFD, OldDecl)) 3026 return NewFD->setInvalidDecl(); 3027 3028 if (FunctionTemplateDecl *OldTemplateDecl 3029 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3030 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3031 FunctionTemplateDecl *NewTemplateDecl 3032 = NewFD->getDescribedFunctionTemplate(); 3033 assert(NewTemplateDecl && "Template/non-template mismatch"); 3034 if (CXXMethodDecl *Method 3035 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3036 Method->setAccess(OldTemplateDecl->getAccess()); 3037 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3038 } 3039 3040 // If this is an explicit specialization of a member that is a function 3041 // template, mark it as a member specialization. 3042 if (IsExplicitSpecialization && 3043 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3044 NewTemplateDecl->setMemberSpecialization(); 3045 assert(OldTemplateDecl->isMemberSpecialization()); 3046 } 3047 } else { 3048 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3049 NewFD->setAccess(OldDecl->getAccess()); 3050 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3051 } 3052 } 3053 } 3054 3055 // Semantic checking for this function declaration (in isolation). 3056 if (getLangOptions().CPlusPlus) { 3057 // C++-specific checks. 3058 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3059 CheckConstructor(Constructor); 3060 } else if (isa<CXXDestructorDecl>(NewFD)) { 3061 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 3062 QualType ClassType = Context.getTypeDeclType(Record); 3063 if (!ClassType->isDependentType()) { 3064 DeclarationName Name 3065 = Context.DeclarationNames.getCXXDestructorName( 3066 Context.getCanonicalType(ClassType)); 3067 if (NewFD->getDeclName() != Name) { 3068 Diag(NewFD->getLocation(), diag::err_destructor_name); 3069 return NewFD->setInvalidDecl(); 3070 } 3071 } 3072 Record->setUserDeclaredDestructor(true); 3073 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3074 // user-defined destructor. 3075 Record->setPOD(false); 3076 3077 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3078 // declared destructor. 3079 // FIXME: C++0x: don't do this for "= default" destructors 3080 Record->setHasTrivialDestructor(false); 3081 } else if (CXXConversionDecl *Conversion 3082 = dyn_cast<CXXConversionDecl>(NewFD)) 3083 ActOnConversionDeclarator(Conversion); 3084 3085 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3086 if (NewFD->isOverloadedOperator() && 3087 CheckOverloadedOperatorDeclaration(NewFD)) 3088 return NewFD->setInvalidDecl(); 3089 3090 // In C++, check default arguments now that we have merged decls. Unless 3091 // the lexical context is the class, because in this case this is done 3092 // during delayed parsing anyway. 3093 if (!CurContext->isRecord()) 3094 CheckCXXDefaultArguments(NewFD); 3095 } 3096} 3097 3098void Sema::CheckMain(FunctionDecl* FD) { 3099 // C++ [basic.start.main]p3: A program that declares main to be inline 3100 // or static is ill-formed. 3101 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3102 // shall not appear in a declaration of main. 3103 // static main is not an error under C99, but we should warn about it. 3104 bool isInline = FD->isInline(); 3105 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3106 if (isInline || isStatic) { 3107 unsigned diagID = diag::warn_unusual_main_decl; 3108 if (isInline || getLangOptions().CPlusPlus) 3109 diagID = diag::err_unusual_main_decl; 3110 3111 int which = isStatic + (isInline << 1) - 1; 3112 Diag(FD->getLocation(), diagID) << which; 3113 } 3114 3115 QualType T = FD->getType(); 3116 assert(T->isFunctionType() && "function decl is not of function type"); 3117 const FunctionType* FT = T->getAs<FunctionType>(); 3118 3119 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3120 // TODO: add a replacement fixit to turn the return type into 'int'. 3121 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3122 FD->setInvalidDecl(true); 3123 } 3124 3125 // Treat protoless main() as nullary. 3126 if (isa<FunctionNoProtoType>(FT)) return; 3127 3128 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3129 unsigned nparams = FTP->getNumArgs(); 3130 assert(FD->getNumParams() == nparams); 3131 3132 if (nparams > 3) { 3133 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3134 FD->setInvalidDecl(true); 3135 nparams = 3; 3136 } 3137 3138 // FIXME: a lot of the following diagnostics would be improved 3139 // if we had some location information about types. 3140 3141 QualType CharPP = 3142 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3143 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3144 3145 for (unsigned i = 0; i < nparams; ++i) { 3146 QualType AT = FTP->getArgType(i); 3147 3148 bool mismatch = true; 3149 3150 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3151 mismatch = false; 3152 else if (Expected[i] == CharPP) { 3153 // As an extension, the following forms are okay: 3154 // char const ** 3155 // char const * const * 3156 // char * const * 3157 3158 QualifierCollector qs; 3159 const PointerType* PT; 3160 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3161 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3162 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3163 qs.removeConst(); 3164 mismatch = !qs.empty(); 3165 } 3166 } 3167 3168 if (mismatch) { 3169 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3170 // TODO: suggest replacing given type with expected type 3171 FD->setInvalidDecl(true); 3172 } 3173 } 3174 3175 if (nparams == 1 && !FD->isInvalidDecl()) { 3176 Diag(FD->getLocation(), diag::warn_main_one_arg); 3177 } 3178} 3179 3180bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3181 // FIXME: Need strict checking. In C89, we need to check for 3182 // any assignment, increment, decrement, function-calls, or 3183 // commas outside of a sizeof. In C99, it's the same list, 3184 // except that the aforementioned are allowed in unevaluated 3185 // expressions. Everything else falls under the 3186 // "may accept other forms of constant expressions" exception. 3187 // (We never end up here for C++, so the constant expression 3188 // rules there don't matter.) 3189 if (Init->isConstantInitializer(Context)) 3190 return false; 3191 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3192 << Init->getSourceRange(); 3193 return true; 3194} 3195 3196void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3197 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3198} 3199 3200/// AddInitializerToDecl - Adds the initializer Init to the 3201/// declaration dcl. If DirectInit is true, this is C++ direct 3202/// initialization rather than copy initialization. 3203void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3204 Decl *RealDecl = dcl.getAs<Decl>(); 3205 // If there is no declaration, there was an error parsing it. Just ignore 3206 // the initializer. 3207 if (RealDecl == 0) 3208 return; 3209 3210 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3211 // With declarators parsed the way they are, the parser cannot 3212 // distinguish between a normal initializer and a pure-specifier. 3213 // Thus this grotesque test. 3214 IntegerLiteral *IL; 3215 Expr *Init = static_cast<Expr *>(init.get()); 3216 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3217 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3218 if (Method->isVirtualAsWritten()) { 3219 Method->setPure(); 3220 3221 // A class is abstract if at least one function is pure virtual. 3222 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3223 } else if (!Method->isInvalidDecl()) { 3224 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3225 << Method->getDeclName() << Init->getSourceRange(); 3226 Method->setInvalidDecl(); 3227 } 3228 } else { 3229 Diag(Method->getLocation(), diag::err_member_function_initialization) 3230 << Method->getDeclName() << Init->getSourceRange(); 3231 Method->setInvalidDecl(); 3232 } 3233 return; 3234 } 3235 3236 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3237 if (!VDecl) { 3238 if (getLangOptions().CPlusPlus && 3239 RealDecl->getLexicalDeclContext()->isRecord() && 3240 isa<NamedDecl>(RealDecl)) 3241 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3242 << cast<NamedDecl>(RealDecl)->getDeclName(); 3243 else 3244 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3245 RealDecl->setInvalidDecl(); 3246 return; 3247 } 3248 3249 if (!VDecl->getType()->isArrayType() && 3250 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 3251 diag::err_typecheck_decl_incomplete_type)) { 3252 RealDecl->setInvalidDecl(); 3253 return; 3254 } 3255 3256 const VarDecl *Def = 0; 3257 if (VDecl->getDefinition(Def)) { 3258 Diag(VDecl->getLocation(), diag::err_redefinition) 3259 << VDecl->getDeclName(); 3260 Diag(Def->getLocation(), diag::note_previous_definition); 3261 VDecl->setInvalidDecl(); 3262 return; 3263 } 3264 3265 // Take ownership of the expression, now that we're sure we have somewhere 3266 // to put it. 3267 Expr *Init = init.takeAs<Expr>(); 3268 assert(Init && "missing initializer"); 3269 3270 // Get the decls type and save a reference for later, since 3271 // CheckInitializerTypes may change it. 3272 QualType DclT = VDecl->getType(), SavT = DclT; 3273 if (VDecl->isBlockVarDecl()) { 3274 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3275 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3276 VDecl->setInvalidDecl(); 3277 } else if (!VDecl->isInvalidDecl()) { 3278 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3279 VDecl->getDeclName(), DirectInit)) 3280 VDecl->setInvalidDecl(); 3281 3282 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3283 // Don't check invalid declarations to avoid emitting useless diagnostics. 3284 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3285 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3286 CheckForConstantInitializer(Init, DclT); 3287 } 3288 } 3289 } else if (VDecl->isStaticDataMember() && 3290 VDecl->getLexicalDeclContext()->isRecord()) { 3291 // This is an in-class initialization for a static data member, e.g., 3292 // 3293 // struct S { 3294 // static const int value = 17; 3295 // }; 3296 3297 // Attach the initializer 3298 VDecl->setInit(Context, Init); 3299 3300 // C++ [class.mem]p4: 3301 // A member-declarator can contain a constant-initializer only 3302 // if it declares a static member (9.4) of const integral or 3303 // const enumeration type, see 9.4.2. 3304 QualType T = VDecl->getType(); 3305 if (!T->isDependentType() && 3306 (!Context.getCanonicalType(T).isConstQualified() || 3307 !T->isIntegralType())) { 3308 Diag(VDecl->getLocation(), diag::err_member_initialization) 3309 << VDecl->getDeclName() << Init->getSourceRange(); 3310 VDecl->setInvalidDecl(); 3311 } else { 3312 // C++ [class.static.data]p4: 3313 // If a static data member is of const integral or const 3314 // enumeration type, its declaration in the class definition 3315 // can specify a constant-initializer which shall be an 3316 // integral constant expression (5.19). 3317 if (!Init->isTypeDependent() && 3318 !Init->getType()->isIntegralType()) { 3319 // We have a non-dependent, non-integral or enumeration type. 3320 Diag(Init->getSourceRange().getBegin(), 3321 diag::err_in_class_initializer_non_integral_type) 3322 << Init->getType() << Init->getSourceRange(); 3323 VDecl->setInvalidDecl(); 3324 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3325 // Check whether the expression is a constant expression. 3326 llvm::APSInt Value; 3327 SourceLocation Loc; 3328 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3329 Diag(Loc, diag::err_in_class_initializer_non_constant) 3330 << Init->getSourceRange(); 3331 VDecl->setInvalidDecl(); 3332 } else if (!VDecl->getType()->isDependentType()) 3333 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3334 } 3335 } 3336 } else if (VDecl->isFileVarDecl()) { 3337 if (VDecl->getStorageClass() == VarDecl::Extern) 3338 Diag(VDecl->getLocation(), diag::warn_extern_init); 3339 if (!VDecl->isInvalidDecl()) 3340 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3341 VDecl->getDeclName(), DirectInit)) 3342 VDecl->setInvalidDecl(); 3343 3344 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3345 // Don't check invalid declarations to avoid emitting useless diagnostics. 3346 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3347 // C99 6.7.8p4. All file scoped initializers need to be constant. 3348 CheckForConstantInitializer(Init, DclT); 3349 } 3350 } 3351 // If the type changed, it means we had an incomplete type that was 3352 // completed by the initializer. For example: 3353 // int ary[] = { 1, 3, 5 }; 3354 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3355 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3356 VDecl->setType(DclT); 3357 Init->setType(DclT); 3358 } 3359 3360 Init = MaybeCreateCXXExprWithTemporaries(Init, 3361 /*ShouldDestroyTemporaries=*/true); 3362 // Attach the initializer to the decl. 3363 VDecl->setInit(Context, Init); 3364 3365 // If the previous declaration of VDecl was a tentative definition, 3366 // remove it from the set of tentative definitions. 3367 if (VDecl->getPreviousDeclaration() && 3368 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3369 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3370 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3371 } 3372 3373 return; 3374} 3375 3376void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3377 bool TypeContainsUndeducedAuto) { 3378 Decl *RealDecl = dcl.getAs<Decl>(); 3379 3380 // If there is no declaration, there was an error parsing it. Just ignore it. 3381 if (RealDecl == 0) 3382 return; 3383 3384 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3385 QualType Type = Var->getType(); 3386 3387 // Record tentative definitions. 3388 if (Var->isTentativeDefinition(Context)) { 3389 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3390 InsertPair = 3391 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3392 3393 // Keep the latest definition in the map. If we see 'int i; int i;' we 3394 // want the second one in the map. 3395 InsertPair.first->second = Var; 3396 3397 // However, for the list, we don't care about the order, just make sure 3398 // that there are no dupes for a given declaration name. 3399 if (InsertPair.second) 3400 TentativeDefinitionList.push_back(Var->getDeclName()); 3401 } 3402 3403 // C++ [dcl.init.ref]p3: 3404 // The initializer can be omitted for a reference only in a 3405 // parameter declaration (8.3.5), in the declaration of a 3406 // function return type, in the declaration of a class member 3407 // within its class declaration (9.2), and where the extern 3408 // specifier is explicitly used. 3409 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3410 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3411 << Var->getDeclName() 3412 << SourceRange(Var->getLocation(), Var->getLocation()); 3413 Var->setInvalidDecl(); 3414 return; 3415 } 3416 3417 // C++0x [dcl.spec.auto]p3 3418 if (TypeContainsUndeducedAuto) { 3419 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3420 << Var->getDeclName() << Type; 3421 Var->setInvalidDecl(); 3422 return; 3423 } 3424 3425 // C++ [temp.expl.spec]p15: 3426 // An explicit specialization of a static data member of a template is a 3427 // definition if the declaration includes an initializer; otherwise, it 3428 // is a declaration. 3429 if (Var->isStaticDataMember() && 3430 Var->getInstantiatedFromStaticDataMember() && 3431 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3432 return; 3433 3434 // C++ [dcl.init]p9: 3435 // If no initializer is specified for an object, and the object 3436 // is of (possibly cv-qualified) non-POD class type (or array 3437 // thereof), the object shall be default-initialized; if the 3438 // object is of const-qualified type, the underlying class type 3439 // shall have a user-declared default constructor. 3440 // 3441 // FIXME: Diagnose the "user-declared default constructor" bit. 3442 if (getLangOptions().CPlusPlus) { 3443 QualType InitType = Type; 3444 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3445 InitType = Array->getElementType(); 3446 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3447 InitType->isRecordType() && !InitType->isDependentType()) { 3448 if (!RequireCompleteType(Var->getLocation(), InitType, 3449 diag::err_invalid_incomplete_type_use)) { 3450 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3451 3452 CXXConstructorDecl *Constructor 3453 = PerformInitializationByConstructor(InitType, 3454 MultiExprArg(*this, 0, 0), 3455 Var->getLocation(), 3456 SourceRange(Var->getLocation(), 3457 Var->getLocation()), 3458 Var->getDeclName(), 3459 IK_Default, 3460 ConstructorArgs); 3461 3462 // FIXME: Location info for the variable initialization? 3463 if (!Constructor) 3464 Var->setInvalidDecl(); 3465 else { 3466 // FIXME: Cope with initialization of arrays 3467 if (!Constructor->isTrivial() && 3468 InitializeVarWithConstructor(Var, Constructor, InitType, 3469 move_arg(ConstructorArgs))) 3470 Var->setInvalidDecl(); 3471 3472 FinalizeVarWithDestructor(Var, InitType); 3473 } 3474 } else { 3475 Var->setInvalidDecl(); 3476 } 3477 } 3478 } 3479 3480#if 0 3481 // FIXME: Temporarily disabled because we are not properly parsing 3482 // linkage specifications on declarations, e.g., 3483 // 3484 // extern "C" const CGPoint CGPointerZero; 3485 // 3486 // C++ [dcl.init]p9: 3487 // 3488 // If no initializer is specified for an object, and the 3489 // object is of (possibly cv-qualified) non-POD class type (or 3490 // array thereof), the object shall be default-initialized; if 3491 // the object is of const-qualified type, the underlying class 3492 // type shall have a user-declared default 3493 // constructor. Otherwise, if no initializer is specified for 3494 // an object, the object and its subobjects, if any, have an 3495 // indeterminate initial value; if the object or any of its 3496 // subobjects are of const-qualified type, the program is 3497 // ill-formed. 3498 // 3499 // This isn't technically an error in C, so we don't diagnose it. 3500 // 3501 // FIXME: Actually perform the POD/user-defined default 3502 // constructor check. 3503 if (getLangOptions().CPlusPlus && 3504 Context.getCanonicalType(Type).isConstQualified() && 3505 !Var->hasExternalStorage()) 3506 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3507 << Var->getName() 3508 << SourceRange(Var->getLocation(), Var->getLocation()); 3509#endif 3510 } 3511} 3512 3513Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3514 DeclPtrTy *Group, 3515 unsigned NumDecls) { 3516 llvm::SmallVector<Decl*, 8> Decls; 3517 3518 if (DS.isTypeSpecOwned()) 3519 Decls.push_back((Decl*)DS.getTypeRep()); 3520 3521 for (unsigned i = 0; i != NumDecls; ++i) 3522 if (Decl *D = Group[i].getAs<Decl>()) 3523 Decls.push_back(D); 3524 3525 // Perform semantic analysis that depends on having fully processed both 3526 // the declarator and initializer. 3527 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3528 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3529 if (!IDecl) 3530 continue; 3531 QualType T = IDecl->getType(); 3532 3533 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3534 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3535 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3536 if (T->isDependentType()) { 3537 // If T is dependent, we should not require a complete type. 3538 // (RequireCompleteType shouldn't be called with dependent types.) 3539 // But we still can at least check if we've got an array of unspecified 3540 // size without an initializer. 3541 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3542 !IDecl->getInit()) { 3543 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3544 << T; 3545 IDecl->setInvalidDecl(); 3546 } 3547 } else if (!IDecl->isInvalidDecl()) { 3548 // If T is an incomplete array type with an initializer list that is 3549 // dependent on something, its size has not been fixed. We could attempt 3550 // to fix the size for such arrays, but we would still have to check 3551 // here for initializers containing a C++0x vararg expansion, e.g. 3552 // template <typename... Args> void f(Args... args) { 3553 // int vals[] = { args }; 3554 // } 3555 const IncompleteArrayType *IAT = T->getAs<IncompleteArrayType>(); 3556 Expr *Init = IDecl->getInit(); 3557 if (IAT && Init && 3558 (Init->isTypeDependent() || Init->isValueDependent())) { 3559 // Check that the member type of the array is complete, at least. 3560 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3561 diag::err_typecheck_decl_incomplete_type)) 3562 IDecl->setInvalidDecl(); 3563 } else if (RequireCompleteType(IDecl->getLocation(), T, 3564 diag::err_typecheck_decl_incomplete_type)) 3565 IDecl->setInvalidDecl(); 3566 } 3567 } 3568 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3569 // object that has file scope without an initializer, and without a 3570 // storage-class specifier or with the storage-class specifier "static", 3571 // constitutes a tentative definition. Note: A tentative definition with 3572 // external linkage is valid (C99 6.2.2p5). 3573 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3574 if (const IncompleteArrayType *ArrayT 3575 = Context.getAsIncompleteArrayType(T)) { 3576 if (RequireCompleteType(IDecl->getLocation(), 3577 ArrayT->getElementType(), 3578 diag::err_illegal_decl_array_incomplete_type)) 3579 IDecl->setInvalidDecl(); 3580 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3581 // C99 6.9.2p3: If the declaration of an identifier for an object is 3582 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3583 // declared type shall not be an incomplete type. 3584 // NOTE: code such as the following 3585 // static struct s; 3586 // struct s { int a; }; 3587 // is accepted by gcc. Hence here we issue a warning instead of 3588 // an error and we do not invalidate the static declaration. 3589 // NOTE: to avoid multiple warnings, only check the first declaration. 3590 if (IDecl->getPreviousDeclaration() == 0) 3591 RequireCompleteType(IDecl->getLocation(), T, 3592 diag::ext_typecheck_decl_incomplete_type); 3593 } 3594 } 3595 } 3596 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3597 Decls.data(), Decls.size())); 3598} 3599 3600 3601/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3602/// to introduce parameters into function prototype scope. 3603Sema::DeclPtrTy 3604Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3605 const DeclSpec &DS = D.getDeclSpec(); 3606 3607 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3608 VarDecl::StorageClass StorageClass = VarDecl::None; 3609 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3610 StorageClass = VarDecl::Register; 3611 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3612 Diag(DS.getStorageClassSpecLoc(), 3613 diag::err_invalid_storage_class_in_func_decl); 3614 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3615 } 3616 3617 if (D.getDeclSpec().isThreadSpecified()) 3618 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3619 3620 DiagnoseFunctionSpecifiers(D); 3621 3622 // Check that there are no default arguments inside the type of this 3623 // parameter (C++ only). 3624 if (getLangOptions().CPlusPlus) 3625 CheckExtraCXXDefaultArguments(D); 3626 3627 DeclaratorInfo *DInfo = 0; 3628 TagDecl *OwnedDecl = 0; 3629 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3630 3631 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3632 // C++ [dcl.fct]p6: 3633 // Types shall not be defined in return or parameter types. 3634 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3635 << Context.getTypeDeclType(OwnedDecl); 3636 } 3637 3638 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3639 // Can this happen for params? We already checked that they don't conflict 3640 // among each other. Here they can only shadow globals, which is ok. 3641 IdentifierInfo *II = D.getIdentifier(); 3642 if (II) { 3643 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3644 if (PrevDecl->isTemplateParameter()) { 3645 // Maybe we will complain about the shadowed template parameter. 3646 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3647 // Just pretend that we didn't see the previous declaration. 3648 PrevDecl = 0; 3649 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3650 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3651 3652 // Recover by removing the name 3653 II = 0; 3654 D.SetIdentifier(0, D.getIdentifierLoc()); 3655 } 3656 } 3657 } 3658 3659 // Parameters can not be abstract class types. 3660 // For record types, this is done by the AbstractClassUsageDiagnoser once 3661 // the class has been completely parsed. 3662 if (!CurContext->isRecord() && 3663 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3664 diag::err_abstract_type_in_decl, 3665 AbstractParamType)) 3666 D.setInvalidType(true); 3667 3668 QualType T = adjustParameterType(parmDeclType); 3669 3670 ParmVarDecl *New 3671 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3672 T, DInfo, StorageClass, 0); 3673 3674 if (D.isInvalidType()) 3675 New->setInvalidDecl(); 3676 3677 // Parameter declarators cannot be interface types. All ObjC objects are 3678 // passed by reference. 3679 if (T->isObjCInterfaceType()) { 3680 Diag(D.getIdentifierLoc(), 3681 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3682 New->setInvalidDecl(); 3683 } 3684 3685 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3686 if (D.getCXXScopeSpec().isSet()) { 3687 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3688 << D.getCXXScopeSpec().getRange(); 3689 New->setInvalidDecl(); 3690 } 3691 3692 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3693 // duration shall not be qualified by an address-space qualifier." 3694 // Since all parameters have automatic store duration, they can not have 3695 // an address space. 3696 if (T.getAddressSpace() != 0) { 3697 Diag(D.getIdentifierLoc(), 3698 diag::err_arg_with_address_space); 3699 New->setInvalidDecl(); 3700 } 3701 3702 3703 // Add the parameter declaration into this scope. 3704 S->AddDecl(DeclPtrTy::make(New)); 3705 if (II) 3706 IdResolver.AddDecl(New); 3707 3708 ProcessDeclAttributes(S, New, D); 3709 3710 if (New->hasAttr<BlocksAttr>()) { 3711 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3712 } 3713 return DeclPtrTy::make(New); 3714} 3715 3716void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3717 SourceLocation LocAfterDecls) { 3718 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3719 "Not a function declarator!"); 3720 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3721 3722 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3723 // for a K&R function. 3724 if (!FTI.hasPrototype) { 3725 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3726 --i; 3727 if (FTI.ArgInfo[i].Param == 0) { 3728 llvm::SmallString<256> Code; 3729 llvm::raw_svector_ostream(Code) << " int " 3730 << FTI.ArgInfo[i].Ident->getName() 3731 << ";\n"; 3732 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3733 << FTI.ArgInfo[i].Ident 3734 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3735 3736 // Implicitly declare the argument as type 'int' for lack of a better 3737 // type. 3738 DeclSpec DS; 3739 const char* PrevSpec; // unused 3740 unsigned DiagID; // unused 3741 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3742 PrevSpec, DiagID); 3743 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3744 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3745 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3746 } 3747 } 3748 } 3749} 3750 3751Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3752 Declarator &D) { 3753 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3754 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3755 "Not a function declarator!"); 3756 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3757 3758 if (FTI.hasPrototype) { 3759 // FIXME: Diagnose arguments without names in C. 3760 } 3761 3762 Scope *ParentScope = FnBodyScope->getParent(); 3763 3764 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3765 MultiTemplateParamsArg(*this), 3766 /*IsFunctionDefinition=*/true); 3767 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3768} 3769 3770Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3771 if (!D) 3772 return D; 3773 FunctionDecl *FD = 0; 3774 3775 if (FunctionTemplateDecl *FunTmpl 3776 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3777 FD = FunTmpl->getTemplatedDecl(); 3778 else 3779 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3780 3781 CurFunctionNeedsScopeChecking = false; 3782 3783 // See if this is a redefinition. 3784 const FunctionDecl *Definition; 3785 if (FD->getBody(Definition)) { 3786 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3787 Diag(Definition->getLocation(), diag::note_previous_definition); 3788 } 3789 3790 // Builtin functions cannot be defined. 3791 if (unsigned BuiltinID = FD->getBuiltinID()) { 3792 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3793 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3794 FD->setInvalidDecl(); 3795 } 3796 } 3797 3798 // The return type of a function definition must be complete 3799 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3800 QualType ResultType = FD->getResultType(); 3801 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3802 !FD->isInvalidDecl() && 3803 RequireCompleteType(FD->getLocation(), ResultType, 3804 diag::err_func_def_incomplete_result)) 3805 FD->setInvalidDecl(); 3806 3807 // GNU warning -Wmissing-prototypes: 3808 // Warn if a global function is defined without a previous 3809 // prototype declaration. This warning is issued even if the 3810 // definition itself provides a prototype. The aim is to detect 3811 // global functions that fail to be declared in header files. 3812 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3813 !FD->isMain()) { 3814 bool MissingPrototype = true; 3815 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3816 Prev; Prev = Prev->getPreviousDeclaration()) { 3817 // Ignore any declarations that occur in function or method 3818 // scope, because they aren't visible from the header. 3819 if (Prev->getDeclContext()->isFunctionOrMethod()) 3820 continue; 3821 3822 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3823 break; 3824 } 3825 3826 if (MissingPrototype) 3827 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3828 } 3829 3830 if (FnBodyScope) 3831 PushDeclContext(FnBodyScope, FD); 3832 3833 // Check the validity of our function parameters 3834 CheckParmsForFunctionDef(FD); 3835 3836 // Introduce our parameters into the function scope 3837 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3838 ParmVarDecl *Param = FD->getParamDecl(p); 3839 Param->setOwningFunction(FD); 3840 3841 // If this has an identifier, add it to the scope stack. 3842 if (Param->getIdentifier() && FnBodyScope) 3843 PushOnScopeChains(Param, FnBodyScope); 3844 } 3845 3846 // Checking attributes of current function definition 3847 // dllimport attribute. 3848 if (FD->getAttr<DLLImportAttr>() && 3849 (!FD->getAttr<DLLExportAttr>())) { 3850 // dllimport attribute cannot be applied to definition. 3851 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3852 Diag(FD->getLocation(), 3853 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3854 << "dllimport"; 3855 FD->setInvalidDecl(); 3856 return DeclPtrTy::make(FD); 3857 } else { 3858 // If a symbol previously declared dllimport is later defined, the 3859 // attribute is ignored in subsequent references, and a warning is 3860 // emitted. 3861 Diag(FD->getLocation(), 3862 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3863 << FD->getNameAsCString() << "dllimport"; 3864 } 3865 } 3866 return DeclPtrTy::make(FD); 3867} 3868 3869Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3870 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3871} 3872 3873Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3874 bool IsInstantiation) { 3875 Decl *dcl = D.getAs<Decl>(); 3876 Stmt *Body = BodyArg.takeAs<Stmt>(); 3877 3878 FunctionDecl *FD = 0; 3879 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3880 if (FunTmpl) 3881 FD = FunTmpl->getTemplatedDecl(); 3882 else 3883 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3884 3885 if (FD) { 3886 FD->setBody(Body); 3887 if (FD->isMain()) 3888 // C and C++ allow for main to automagically return 0. 3889 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3890 FD->setHasImplicitReturnZero(true); 3891 else 3892 CheckFallThroughForFunctionDef(FD, Body); 3893 3894 if (!FD->isInvalidDecl()) 3895 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3896 3897 // C++ [basic.def.odr]p2: 3898 // [...] A virtual member function is used if it is not pure. [...] 3899 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3900 if (Method->isVirtual() && !Method->isPure()) 3901 MarkDeclarationReferenced(Method->getLocation(), Method); 3902 3903 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3904 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3905 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3906 MD->setBody(Body); 3907 CheckFallThroughForFunctionDef(MD, Body); 3908 MD->setEndLoc(Body->getLocEnd()); 3909 3910 if (!MD->isInvalidDecl()) 3911 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3912 } else { 3913 Body->Destroy(Context); 3914 return DeclPtrTy(); 3915 } 3916 if (!IsInstantiation) 3917 PopDeclContext(); 3918 3919 // Verify and clean out per-function state. 3920 3921 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3922 3923 // Check goto/label use. 3924 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3925 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3926 LabelStmt *L = I->second; 3927 3928 // Verify that we have no forward references left. If so, there was a goto 3929 // or address of a label taken, but no definition of it. Label fwd 3930 // definitions are indicated with a null substmt. 3931 if (L->getSubStmt() != 0) 3932 continue; 3933 3934 // Emit error. 3935 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3936 3937 // At this point, we have gotos that use the bogus label. Stitch it into 3938 // the function body so that they aren't leaked and that the AST is well 3939 // formed. 3940 if (Body == 0) { 3941 // The whole function wasn't parsed correctly, just delete this. 3942 L->Destroy(Context); 3943 continue; 3944 } 3945 3946 // Otherwise, the body is valid: we want to stitch the label decl into the 3947 // function somewhere so that it is properly owned and so that the goto 3948 // has a valid target. Do this by creating a new compound stmt with the 3949 // label in it. 3950 3951 // Give the label a sub-statement. 3952 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3953 3954 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3955 cast<CXXTryStmt>(Body)->getTryBlock() : 3956 cast<CompoundStmt>(Body); 3957 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3958 Elements.push_back(L); 3959 Compound->setStmts(Context, &Elements[0], Elements.size()); 3960 } 3961 FunctionLabelMap.clear(); 3962 3963 if (!Body) return D; 3964 3965 // Verify that that gotos and switch cases don't jump into scopes illegally. 3966 if (CurFunctionNeedsScopeChecking) 3967 DiagnoseInvalidJumps(Body); 3968 3969 // C++ constructors that have function-try-blocks can't have return 3970 // statements in the handlers of that block. (C++ [except.handle]p14) 3971 // Verify this. 3972 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 3973 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3974 3975 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 3976 computeBaseOrMembersToDestroy(Destructor); 3977 return D; 3978} 3979 3980/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3981/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3982NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3983 IdentifierInfo &II, Scope *S) { 3984 // Before we produce a declaration for an implicitly defined 3985 // function, see whether there was a locally-scoped declaration of 3986 // this name as a function or variable. If so, use that 3987 // (non-visible) declaration, and complain about it. 3988 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3989 = LocallyScopedExternalDecls.find(&II); 3990 if (Pos != LocallyScopedExternalDecls.end()) { 3991 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3992 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3993 return Pos->second; 3994 } 3995 3996 // Extension in C99. Legal in C90, but warn about it. 3997 if (II.getName().startswith("__builtin_")) 3998 Diag(Loc, diag::warn_builtin_unknown) << &II; 3999 else if (getLangOptions().C99) 4000 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4001 else 4002 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4003 4004 // Set a Declarator for the implicit definition: int foo(); 4005 const char *Dummy; 4006 DeclSpec DS; 4007 unsigned DiagID; 4008 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4009 Error = Error; // Silence warning. 4010 assert(!Error && "Error setting up implicit decl!"); 4011 Declarator D(DS, Declarator::BlockContext); 4012 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4013 0, 0, false, SourceLocation(), 4014 false, 0,0,0, Loc, Loc, D), 4015 SourceLocation()); 4016 D.SetIdentifier(&II, Loc); 4017 4018 // Insert this function into translation-unit scope. 4019 4020 DeclContext *PrevDC = CurContext; 4021 CurContext = Context.getTranslationUnitDecl(); 4022 4023 FunctionDecl *FD = 4024 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4025 FD->setImplicit(); 4026 4027 CurContext = PrevDC; 4028 4029 AddKnownFunctionAttributes(FD); 4030 4031 return FD; 4032} 4033 4034/// \brief Adds any function attributes that we know a priori based on 4035/// the declaration of this function. 4036/// 4037/// These attributes can apply both to implicitly-declared builtins 4038/// (like __builtin___printf_chk) or to library-declared functions 4039/// like NSLog or printf. 4040void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4041 if (FD->isInvalidDecl()) 4042 return; 4043 4044 // If this is a built-in function, map its builtin attributes to 4045 // actual attributes. 4046 if (unsigned BuiltinID = FD->getBuiltinID()) { 4047 // Handle printf-formatting attributes. 4048 unsigned FormatIdx; 4049 bool HasVAListArg; 4050 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4051 if (!FD->getAttr<FormatAttr>()) 4052 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4053 HasVAListArg ? 0 : FormatIdx + 2)); 4054 } 4055 4056 // Mark const if we don't care about errno and that is the only 4057 // thing preventing the function from being const. This allows 4058 // IRgen to use LLVM intrinsics for such functions. 4059 if (!getLangOptions().MathErrno && 4060 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4061 if (!FD->getAttr<ConstAttr>()) 4062 FD->addAttr(::new (Context) ConstAttr()); 4063 } 4064 4065 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4066 FD->addAttr(::new (Context) NoReturnAttr()); 4067 } 4068 4069 IdentifierInfo *Name = FD->getIdentifier(); 4070 if (!Name) 4071 return; 4072 if ((!getLangOptions().CPlusPlus && 4073 FD->getDeclContext()->isTranslationUnit()) || 4074 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4075 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4076 LinkageSpecDecl::lang_c)) { 4077 // Okay: this could be a libc/libm/Objective-C function we know 4078 // about. 4079 } else 4080 return; 4081 4082 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4083 // FIXME: NSLog and NSLogv should be target specific 4084 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4085 // FIXME: We known better than our headers. 4086 const_cast<FormatAttr *>(Format)->setType("printf"); 4087 } else 4088 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4089 Name->isStr("NSLogv") ? 0 : 2)); 4090 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4091 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4092 // target-specific builtins, perhaps? 4093 if (!FD->getAttr<FormatAttr>()) 4094 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4095 Name->isStr("vasprintf") ? 0 : 3)); 4096 } 4097} 4098 4099TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4100 DeclaratorInfo *DInfo) { 4101 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4102 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4103 4104 if (!DInfo) { 4105 assert(D.isInvalidType() && "no declarator info for valid type"); 4106 DInfo = Context.getTrivialDeclaratorInfo(T); 4107 } 4108 4109 // Scope manipulation handled by caller. 4110 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4111 D.getIdentifierLoc(), 4112 D.getIdentifier(), 4113 DInfo); 4114 4115 if (const TagType *TT = T->getAs<TagType>()) { 4116 TagDecl *TD = TT->getDecl(); 4117 4118 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4119 // keep track of the TypedefDecl. 4120 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4121 TD->setTypedefForAnonDecl(NewTD); 4122 } 4123 4124 if (D.isInvalidType()) 4125 NewTD->setInvalidDecl(); 4126 return NewTD; 4127} 4128 4129 4130/// \brief Determine whether a tag with a given kind is acceptable 4131/// as a redeclaration of the given tag declaration. 4132/// 4133/// \returns true if the new tag kind is acceptable, false otherwise. 4134bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4135 TagDecl::TagKind NewTag, 4136 SourceLocation NewTagLoc, 4137 const IdentifierInfo &Name) { 4138 // C++ [dcl.type.elab]p3: 4139 // The class-key or enum keyword present in the 4140 // elaborated-type-specifier shall agree in kind with the 4141 // declaration to which the name in theelaborated-type-specifier 4142 // refers. This rule also applies to the form of 4143 // elaborated-type-specifier that declares a class-name or 4144 // friend class since it can be construed as referring to the 4145 // definition of the class. Thus, in any 4146 // elaborated-type-specifier, the enum keyword shall be used to 4147 // refer to an enumeration (7.2), the union class-keyshall be 4148 // used to refer to a union (clause 9), and either the class or 4149 // struct class-key shall be used to refer to a class (clause 9) 4150 // declared using the class or struct class-key. 4151 TagDecl::TagKind OldTag = Previous->getTagKind(); 4152 if (OldTag == NewTag) 4153 return true; 4154 4155 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4156 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4157 // Warn about the struct/class tag mismatch. 4158 bool isTemplate = false; 4159 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4160 isTemplate = Record->getDescribedClassTemplate(); 4161 4162 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4163 << (NewTag == TagDecl::TK_class) 4164 << isTemplate << &Name 4165 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4166 OldTag == TagDecl::TK_class? "class" : "struct"); 4167 Diag(Previous->getLocation(), diag::note_previous_use); 4168 return true; 4169 } 4170 return false; 4171} 4172 4173/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4174/// former case, Name will be non-null. In the later case, Name will be null. 4175/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4176/// reference/declaration/definition of a tag. 4177Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4178 SourceLocation KWLoc, const CXXScopeSpec &SS, 4179 IdentifierInfo *Name, SourceLocation NameLoc, 4180 AttributeList *Attr, AccessSpecifier AS, 4181 MultiTemplateParamsArg TemplateParameterLists, 4182 bool &OwnedDecl, bool &IsDependent) { 4183 // If this is not a definition, it must have a name. 4184 assert((Name != 0 || TUK == TUK_Definition) && 4185 "Nameless record must be a definition!"); 4186 4187 OwnedDecl = false; 4188 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4189 4190 // FIXME: Check explicit specializations more carefully. 4191 bool isExplicitSpecialization = false; 4192 if (TUK != TUK_Reference) { 4193 if (TemplateParameterList *TemplateParams 4194 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4195 (TemplateParameterList**)TemplateParameterLists.get(), 4196 TemplateParameterLists.size(), 4197 isExplicitSpecialization)) { 4198 if (TemplateParams->size() > 0) { 4199 // This is a declaration or definition of a class template (which may 4200 // be a member of another template). 4201 OwnedDecl = false; 4202 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4203 SS, Name, NameLoc, Attr, 4204 TemplateParams, 4205 AS); 4206 TemplateParameterLists.release(); 4207 return Result.get(); 4208 } else { 4209 // The "template<>" header is extraneous. 4210 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4211 << ElaboratedType::getNameForTagKind(Kind) << Name; 4212 isExplicitSpecialization = true; 4213 } 4214 } 4215 4216 TemplateParameterLists.release(); 4217 } 4218 4219 DeclContext *SearchDC = CurContext; 4220 DeclContext *DC = CurContext; 4221 NamedDecl *PrevDecl = 0; 4222 bool isStdBadAlloc = false; 4223 bool Invalid = false; 4224 4225 bool RedeclarationOnly = (TUK != TUK_Reference); 4226 4227 if (Name && SS.isNotEmpty()) { 4228 // We have a nested-name tag ('struct foo::bar'). 4229 4230 // Check for invalid 'foo::'. 4231 if (SS.isInvalid()) { 4232 Name = 0; 4233 goto CreateNewDecl; 4234 } 4235 4236 // If this is a friend or a reference to a class in a dependent 4237 // context, don't try to make a decl for it. 4238 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4239 DC = computeDeclContext(SS, false); 4240 if (!DC) { 4241 IsDependent = true; 4242 return DeclPtrTy(); 4243 } 4244 } 4245 4246 if (RequireCompleteDeclContext(SS)) 4247 return DeclPtrTy::make((Decl *)0); 4248 4249 DC = computeDeclContext(SS, true); 4250 SearchDC = DC; 4251 // Look-up name inside 'foo::'. 4252 LookupResult R; 4253 LookupQualifiedName(R, DC, Name, LookupTagName, RedeclarationOnly); 4254 4255 if (R.isAmbiguous()) { 4256 DiagnoseAmbiguousLookup(R, Name, NameLoc, SS.getRange()); 4257 return DeclPtrTy(); 4258 } 4259 4260 if (R.getKind() == LookupResult::Found) 4261 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4262 4263 // A tag 'foo::bar' must already exist. 4264 if (!PrevDecl) { 4265 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4266 Name = 0; 4267 Invalid = true; 4268 goto CreateNewDecl; 4269 } 4270 } else if (Name) { 4271 // If this is a named struct, check to see if there was a previous forward 4272 // declaration or definition. 4273 // FIXME: We're looking into outer scopes here, even when we 4274 // shouldn't be. Doing so can result in ambiguities that we 4275 // shouldn't be diagnosing. 4276 LookupResult R; 4277 LookupName(R, S, Name, LookupTagName, RedeclarationOnly); 4278 if (R.isAmbiguous()) { 4279 DiagnoseAmbiguousLookup(R, Name, NameLoc); 4280 // FIXME: This is not best way to recover from case like: 4281 // 4282 // struct S s; 4283 // 4284 // causes needless "incomplete type" error later. 4285 Name = 0; 4286 PrevDecl = 0; 4287 Invalid = true; 4288 } else 4289 PrevDecl = R.getAsSingleDecl(Context); 4290 4291 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4292 // FIXME: This makes sure that we ignore the contexts associated 4293 // with C structs, unions, and enums when looking for a matching 4294 // tag declaration or definition. See the similar lookup tweak 4295 // in Sema::LookupName; is there a better way to deal with this? 4296 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4297 SearchDC = SearchDC->getParent(); 4298 } 4299 } 4300 4301 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4302 // Maybe we will complain about the shadowed template parameter. 4303 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4304 // Just pretend that we didn't see the previous declaration. 4305 PrevDecl = 0; 4306 } 4307 4308 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4309 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4310 // This is a declaration of or a reference to "std::bad_alloc". 4311 isStdBadAlloc = true; 4312 4313 if (!PrevDecl && StdBadAlloc) { 4314 // std::bad_alloc has been implicitly declared (but made invisible to 4315 // name lookup). Fill in this implicit declaration as the previous 4316 // declaration, so that the declarations get chained appropriately. 4317 PrevDecl = StdBadAlloc; 4318 } 4319 } 4320 4321 if (PrevDecl) { 4322 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4323 // If this is a use of a previous tag, or if the tag is already declared 4324 // in the same scope (so that the definition/declaration completes or 4325 // rementions the tag), reuse the decl. 4326 if (TUK == TUK_Reference || TUK == TUK_Friend || 4327 isDeclInScope(PrevDecl, SearchDC, S)) { 4328 // Make sure that this wasn't declared as an enum and now used as a 4329 // struct or something similar. 4330 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4331 bool SafeToContinue 4332 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4333 Kind != TagDecl::TK_enum); 4334 if (SafeToContinue) 4335 Diag(KWLoc, diag::err_use_with_wrong_tag) 4336 << Name 4337 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4338 PrevTagDecl->getKindName()); 4339 else 4340 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4341 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4342 4343 if (SafeToContinue) 4344 Kind = PrevTagDecl->getTagKind(); 4345 else { 4346 // Recover by making this an anonymous redefinition. 4347 Name = 0; 4348 PrevDecl = 0; 4349 Invalid = true; 4350 } 4351 } 4352 4353 if (!Invalid) { 4354 // If this is a use, just return the declaration we found. 4355 4356 // FIXME: In the future, return a variant or some other clue 4357 // for the consumer of this Decl to know it doesn't own it. 4358 // For our current ASTs this shouldn't be a problem, but will 4359 // need to be changed with DeclGroups. 4360 if (TUK == TUK_Reference || TUK == TUK_Friend) 4361 return DeclPtrTy::make(PrevDecl); 4362 4363 // Diagnose attempts to redefine a tag. 4364 if (TUK == TUK_Definition) { 4365 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4366 // If we're defining a specialization and the previous definition 4367 // is from an implicit instantiation, don't emit an error 4368 // here; we'll catch this in the general case below. 4369 if (!isExplicitSpecialization || 4370 !isa<CXXRecordDecl>(Def) || 4371 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4372 == TSK_ExplicitSpecialization) { 4373 Diag(NameLoc, diag::err_redefinition) << Name; 4374 Diag(Def->getLocation(), diag::note_previous_definition); 4375 // If this is a redefinition, recover by making this 4376 // struct be anonymous, which will make any later 4377 // references get the previous definition. 4378 Name = 0; 4379 PrevDecl = 0; 4380 Invalid = true; 4381 } 4382 } else { 4383 // If the type is currently being defined, complain 4384 // about a nested redefinition. 4385 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4386 if (Tag->isBeingDefined()) { 4387 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4388 Diag(PrevTagDecl->getLocation(), 4389 diag::note_previous_definition); 4390 Name = 0; 4391 PrevDecl = 0; 4392 Invalid = true; 4393 } 4394 } 4395 4396 // Okay, this is definition of a previously declared or referenced 4397 // tag PrevDecl. We're going to create a new Decl for it. 4398 } 4399 } 4400 // If we get here we have (another) forward declaration or we 4401 // have a definition. Just create a new decl. 4402 4403 } else { 4404 // If we get here, this is a definition of a new tag type in a nested 4405 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4406 // new decl/type. We set PrevDecl to NULL so that the entities 4407 // have distinct types. 4408 PrevDecl = 0; 4409 } 4410 // If we get here, we're going to create a new Decl. If PrevDecl 4411 // is non-NULL, it's a definition of the tag declared by 4412 // PrevDecl. If it's NULL, we have a new definition. 4413 } else { 4414 // PrevDecl is a namespace, template, or anything else 4415 // that lives in the IDNS_Tag identifier namespace. 4416 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4417 // The tag name clashes with a namespace name, issue an error and 4418 // recover by making this tag be anonymous. 4419 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4420 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4421 Name = 0; 4422 PrevDecl = 0; 4423 Invalid = true; 4424 } else { 4425 // The existing declaration isn't relevant to us; we're in a 4426 // new scope, so clear out the previous declaration. 4427 PrevDecl = 0; 4428 } 4429 } 4430 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4431 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4432 // C++ [basic.scope.pdecl]p5: 4433 // -- for an elaborated-type-specifier of the form 4434 // 4435 // class-key identifier 4436 // 4437 // if the elaborated-type-specifier is used in the 4438 // decl-specifier-seq or parameter-declaration-clause of a 4439 // function defined in namespace scope, the identifier is 4440 // declared as a class-name in the namespace that contains 4441 // the declaration; otherwise, except as a friend 4442 // declaration, the identifier is declared in the smallest 4443 // non-class, non-function-prototype scope that contains the 4444 // declaration. 4445 // 4446 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4447 // C structs and unions. 4448 // 4449 // GNU C also supports this behavior as part of its incomplete 4450 // enum types extension, while GNU C++ does not. 4451 // 4452 // Find the context where we'll be declaring the tag. 4453 // FIXME: We would like to maintain the current DeclContext as the 4454 // lexical context, 4455 while (SearchDC->isRecord()) 4456 SearchDC = SearchDC->getParent(); 4457 4458 // Find the scope where we'll be declaring the tag. 4459 while (S->isClassScope() || 4460 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4461 ((S->getFlags() & Scope::DeclScope) == 0) || 4462 (S->getEntity() && 4463 ((DeclContext *)S->getEntity())->isTransparentContext())) 4464 S = S->getParent(); 4465 4466 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4467 // C++ [namespace.memdef]p3: 4468 // If a friend declaration in a non-local class first declares a 4469 // class or function, the friend class or function is a member of 4470 // the innermost enclosing namespace. 4471 while (!SearchDC->isFileContext()) 4472 SearchDC = SearchDC->getParent(); 4473 4474 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4475 while (S->getEntity() != SearchDC) 4476 S = S->getParent(); 4477 } 4478 4479CreateNewDecl: 4480 4481 // If there is an identifier, use the location of the identifier as the 4482 // location of the decl, otherwise use the location of the struct/union 4483 // keyword. 4484 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4485 4486 // Otherwise, create a new declaration. If there is a previous 4487 // declaration of the same entity, the two will be linked via 4488 // PrevDecl. 4489 TagDecl *New; 4490 4491 if (Kind == TagDecl::TK_enum) { 4492 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4493 // enum X { A, B, C } D; D should chain to X. 4494 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4495 cast_or_null<EnumDecl>(PrevDecl)); 4496 // If this is an undefined enum, warn. 4497 if (TUK != TUK_Definition && !Invalid) { 4498 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4499 : diag::ext_forward_ref_enum; 4500 Diag(Loc, DK); 4501 } 4502 } else { 4503 // struct/union/class 4504 4505 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4506 // struct X { int A; } D; D should chain to X. 4507 if (getLangOptions().CPlusPlus) { 4508 // FIXME: Look for a way to use RecordDecl for simple structs. 4509 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4510 cast_or_null<CXXRecordDecl>(PrevDecl)); 4511 4512 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4513 StdBadAlloc = cast<CXXRecordDecl>(New); 4514 } else 4515 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4516 cast_or_null<RecordDecl>(PrevDecl)); 4517 } 4518 4519 if (Kind != TagDecl::TK_enum) { 4520 // Handle #pragma pack: if the #pragma pack stack has non-default 4521 // alignment, make up a packed attribute for this decl. These 4522 // attributes are checked when the ASTContext lays out the 4523 // structure. 4524 // 4525 // It is important for implementing the correct semantics that this 4526 // happen here (in act on tag decl). The #pragma pack stack is 4527 // maintained as a result of parser callbacks which can occur at 4528 // many points during the parsing of a struct declaration (because 4529 // the #pragma tokens are effectively skipped over during the 4530 // parsing of the struct). 4531 if (unsigned Alignment = getPragmaPackAlignment()) 4532 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4533 } 4534 4535 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4536 // C++ [dcl.typedef]p3: 4537 // [...] Similarly, in a given scope, a class or enumeration 4538 // shall not be declared with the same name as a typedef-name 4539 // that is declared in that scope and refers to a type other 4540 // than the class or enumeration itself. 4541 LookupResult Lookup; 4542 LookupName(Lookup, S, Name, LookupOrdinaryName, true); 4543 TypedefDecl *PrevTypedef = 0; 4544 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4545 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4546 4547 NamedDecl *PrevTypedefNamed = PrevTypedef; 4548 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4549 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4550 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4551 Diag(Loc, diag::err_tag_definition_of_typedef) 4552 << Context.getTypeDeclType(New) 4553 << PrevTypedef->getUnderlyingType(); 4554 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4555 Invalid = true; 4556 } 4557 } 4558 4559 // If this is a specialization of a member class (of a class template), 4560 // check the specialization. 4561 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4562 Invalid = true; 4563 4564 if (Invalid) 4565 New->setInvalidDecl(); 4566 4567 if (Attr) 4568 ProcessDeclAttributeList(S, New, Attr); 4569 4570 // If we're declaring or defining a tag in function prototype scope 4571 // in C, note that this type can only be used within the function. 4572 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4573 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4574 4575 // Set the lexical context. If the tag has a C++ scope specifier, the 4576 // lexical context will be different from the semantic context. 4577 New->setLexicalDeclContext(CurContext); 4578 4579 // Mark this as a friend decl if applicable. 4580 if (TUK == TUK_Friend) 4581 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4582 4583 // Set the access specifier. 4584 if (!Invalid && TUK != TUK_Friend) 4585 SetMemberAccessSpecifier(New, PrevDecl, AS); 4586 4587 if (TUK == TUK_Definition) 4588 New->startDefinition(); 4589 4590 // If this has an identifier, add it to the scope stack. 4591 if (TUK == TUK_Friend) { 4592 // We might be replacing an existing declaration in the lookup tables; 4593 // if so, borrow its access specifier. 4594 if (PrevDecl) 4595 New->setAccess(PrevDecl->getAccess()); 4596 4597 // Friend tag decls are visible in fairly strange ways. 4598 if (!CurContext->isDependentContext()) { 4599 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4600 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4601 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4602 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4603 } 4604 } else if (Name) { 4605 S = getNonFieldDeclScope(S); 4606 PushOnScopeChains(New, S); 4607 } else { 4608 CurContext->addDecl(New); 4609 } 4610 4611 // If this is the C FILE type, notify the AST context. 4612 if (IdentifierInfo *II = New->getIdentifier()) 4613 if (!New->isInvalidDecl() && 4614 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4615 II->isStr("FILE")) 4616 Context.setFILEDecl(New); 4617 4618 OwnedDecl = true; 4619 return DeclPtrTy::make(New); 4620} 4621 4622void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4623 AdjustDeclIfTemplate(TagD); 4624 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4625 4626 // Enter the tag context. 4627 PushDeclContext(S, Tag); 4628 4629 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4630 FieldCollector->StartClass(); 4631 4632 if (Record->getIdentifier()) { 4633 // C++ [class]p2: 4634 // [...] The class-name is also inserted into the scope of the 4635 // class itself; this is known as the injected-class-name. For 4636 // purposes of access checking, the injected-class-name is treated 4637 // as if it were a public member name. 4638 CXXRecordDecl *InjectedClassName 4639 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4640 CurContext, Record->getLocation(), 4641 Record->getIdentifier(), 4642 Record->getTagKeywordLoc(), 4643 Record); 4644 InjectedClassName->setImplicit(); 4645 InjectedClassName->setAccess(AS_public); 4646 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4647 InjectedClassName->setDescribedClassTemplate(Template); 4648 PushOnScopeChains(InjectedClassName, S); 4649 assert(InjectedClassName->isInjectedClassName() && 4650 "Broken injected-class-name"); 4651 } 4652 } 4653} 4654 4655void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4656 SourceLocation RBraceLoc) { 4657 AdjustDeclIfTemplate(TagD); 4658 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4659 Tag->setRBraceLoc(RBraceLoc); 4660 4661 if (isa<CXXRecordDecl>(Tag)) 4662 FieldCollector->FinishClass(); 4663 4664 // Exit this scope of this tag's definition. 4665 PopDeclContext(); 4666 4667 // Notify the consumer that we've defined a tag. 4668 Consumer.HandleTagDeclDefinition(Tag); 4669} 4670 4671// Note that FieldName may be null for anonymous bitfields. 4672bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4673 QualType FieldTy, const Expr *BitWidth, 4674 bool *ZeroWidth) { 4675 // Default to true; that shouldn't confuse checks for emptiness 4676 if (ZeroWidth) 4677 *ZeroWidth = true; 4678 4679 // C99 6.7.2.1p4 - verify the field type. 4680 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4681 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4682 // Handle incomplete types with specific error. 4683 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4684 return true; 4685 if (FieldName) 4686 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4687 << FieldName << FieldTy << BitWidth->getSourceRange(); 4688 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4689 << FieldTy << BitWidth->getSourceRange(); 4690 } 4691 4692 // If the bit-width is type- or value-dependent, don't try to check 4693 // it now. 4694 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4695 return false; 4696 4697 llvm::APSInt Value; 4698 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4699 return true; 4700 4701 if (Value != 0 && ZeroWidth) 4702 *ZeroWidth = false; 4703 4704 // Zero-width bitfield is ok for anonymous field. 4705 if (Value == 0 && FieldName) 4706 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4707 4708 if (Value.isSigned() && Value.isNegative()) { 4709 if (FieldName) 4710 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4711 << FieldName << Value.toString(10); 4712 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4713 << Value.toString(10); 4714 } 4715 4716 if (!FieldTy->isDependentType()) { 4717 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4718 if (Value.getZExtValue() > TypeSize) { 4719 if (FieldName) 4720 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4721 << FieldName << (unsigned)TypeSize; 4722 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4723 << (unsigned)TypeSize; 4724 } 4725 } 4726 4727 return false; 4728} 4729 4730/// ActOnField - Each field of a struct/union/class is passed into this in order 4731/// to create a FieldDecl object for it. 4732Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4733 SourceLocation DeclStart, 4734 Declarator &D, ExprTy *BitfieldWidth) { 4735 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4736 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4737 AS_public); 4738 return DeclPtrTy::make(Res); 4739} 4740 4741/// HandleField - Analyze a field of a C struct or a C++ data member. 4742/// 4743FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4744 SourceLocation DeclStart, 4745 Declarator &D, Expr *BitWidth, 4746 AccessSpecifier AS) { 4747 IdentifierInfo *II = D.getIdentifier(); 4748 SourceLocation Loc = DeclStart; 4749 if (II) Loc = D.getIdentifierLoc(); 4750 4751 DeclaratorInfo *DInfo = 0; 4752 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4753 if (getLangOptions().CPlusPlus) 4754 CheckExtraCXXDefaultArguments(D); 4755 4756 DiagnoseFunctionSpecifiers(D); 4757 4758 if (D.getDeclSpec().isThreadSpecified()) 4759 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4760 4761 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 4762 4763 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4764 // Maybe we will complain about the shadowed template parameter. 4765 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4766 // Just pretend that we didn't see the previous declaration. 4767 PrevDecl = 0; 4768 } 4769 4770 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4771 PrevDecl = 0; 4772 4773 bool Mutable 4774 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4775 SourceLocation TSSL = D.getSourceRange().getBegin(); 4776 FieldDecl *NewFD 4777 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4778 AS, PrevDecl, &D); 4779 if (NewFD->isInvalidDecl() && PrevDecl) { 4780 // Don't introduce NewFD into scope; there's already something 4781 // with the same name in the same scope. 4782 } else if (II) { 4783 PushOnScopeChains(NewFD, S); 4784 } else 4785 Record->addDecl(NewFD); 4786 4787 return NewFD; 4788} 4789 4790/// \brief Build a new FieldDecl and check its well-formedness. 4791/// 4792/// This routine builds a new FieldDecl given the fields name, type, 4793/// record, etc. \p PrevDecl should refer to any previous declaration 4794/// with the same name and in the same scope as the field to be 4795/// created. 4796/// 4797/// \returns a new FieldDecl. 4798/// 4799/// \todo The Declarator argument is a hack. It will be removed once 4800FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4801 DeclaratorInfo *DInfo, 4802 RecordDecl *Record, SourceLocation Loc, 4803 bool Mutable, Expr *BitWidth, 4804 SourceLocation TSSL, 4805 AccessSpecifier AS, NamedDecl *PrevDecl, 4806 Declarator *D) { 4807 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4808 bool InvalidDecl = false; 4809 if (D) InvalidDecl = D->isInvalidType(); 4810 4811 // If we receive a broken type, recover by assuming 'int' and 4812 // marking this declaration as invalid. 4813 if (T.isNull()) { 4814 InvalidDecl = true; 4815 T = Context.IntTy; 4816 } 4817 4818 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4819 // than a variably modified type. 4820 if (T->isVariablyModifiedType()) { 4821 bool SizeIsNegative; 4822 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4823 SizeIsNegative); 4824 if (!FixedTy.isNull()) { 4825 Diag(Loc, diag::warn_illegal_constant_array_size); 4826 T = FixedTy; 4827 } else { 4828 if (SizeIsNegative) 4829 Diag(Loc, diag::err_typecheck_negative_array_size); 4830 else 4831 Diag(Loc, diag::err_typecheck_field_variable_size); 4832 InvalidDecl = true; 4833 } 4834 } 4835 4836 // Fields can not have abstract class types 4837 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4838 AbstractFieldType)) 4839 InvalidDecl = true; 4840 4841 bool ZeroWidth = false; 4842 // If this is declared as a bit-field, check the bit-field. 4843 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4844 InvalidDecl = true; 4845 DeleteExpr(BitWidth); 4846 BitWidth = 0; 4847 ZeroWidth = false; 4848 } 4849 4850 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4851 BitWidth, Mutable); 4852 if (InvalidDecl) 4853 NewFD->setInvalidDecl(); 4854 4855 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4856 Diag(Loc, diag::err_duplicate_member) << II; 4857 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4858 NewFD->setInvalidDecl(); 4859 } 4860 4861 if (getLangOptions().CPlusPlus) { 4862 QualType EltTy = Context.getBaseElementType(T); 4863 4864 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4865 4866 if (!T->isPODType()) 4867 CXXRecord->setPOD(false); 4868 if (!ZeroWidth) 4869 CXXRecord->setEmpty(false); 4870 4871 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4872 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4873 4874 if (!RDecl->hasTrivialConstructor()) 4875 CXXRecord->setHasTrivialConstructor(false); 4876 if (!RDecl->hasTrivialCopyConstructor()) 4877 CXXRecord->setHasTrivialCopyConstructor(false); 4878 if (!RDecl->hasTrivialCopyAssignment()) 4879 CXXRecord->setHasTrivialCopyAssignment(false); 4880 if (!RDecl->hasTrivialDestructor()) 4881 CXXRecord->setHasTrivialDestructor(false); 4882 4883 // C++ 9.5p1: An object of a class with a non-trivial 4884 // constructor, a non-trivial copy constructor, a non-trivial 4885 // destructor, or a non-trivial copy assignment operator 4886 // cannot be a member of a union, nor can an array of such 4887 // objects. 4888 // TODO: C++0x alters this restriction significantly. 4889 if (Record->isUnion()) { 4890 // We check for copy constructors before constructors 4891 // because otherwise we'll never get complaints about 4892 // copy constructors. 4893 4894 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4895 4896 CXXSpecialMember member; 4897 if (!RDecl->hasTrivialCopyConstructor()) 4898 member = CXXCopyConstructor; 4899 else if (!RDecl->hasTrivialConstructor()) 4900 member = CXXDefaultConstructor; 4901 else if (!RDecl->hasTrivialCopyAssignment()) 4902 member = CXXCopyAssignment; 4903 else if (!RDecl->hasTrivialDestructor()) 4904 member = CXXDestructor; 4905 else 4906 member = invalid; 4907 4908 if (member != invalid) { 4909 Diag(Loc, diag::err_illegal_union_member) << Name << member; 4910 DiagnoseNontrivial(RT, member); 4911 NewFD->setInvalidDecl(); 4912 } 4913 } 4914 } 4915 } 4916 4917 // FIXME: We need to pass in the attributes given an AST 4918 // representation, not a parser representation. 4919 if (D) 4920 // FIXME: What to pass instead of TUScope? 4921 ProcessDeclAttributes(TUScope, NewFD, *D); 4922 4923 if (T.isObjCGCWeak()) 4924 Diag(Loc, diag::warn_attribute_weak_on_field); 4925 4926 NewFD->setAccess(AS); 4927 4928 // C++ [dcl.init.aggr]p1: 4929 // An aggregate is an array or a class (clause 9) with [...] no 4930 // private or protected non-static data members (clause 11). 4931 // A POD must be an aggregate. 4932 if (getLangOptions().CPlusPlus && 4933 (AS == AS_private || AS == AS_protected)) { 4934 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 4935 CXXRecord->setAggregate(false); 4936 CXXRecord->setPOD(false); 4937 } 4938 4939 return NewFD; 4940} 4941 4942/// DiagnoseNontrivial - Given that a class has a non-trivial 4943/// special member, figure out why. 4944void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 4945 QualType QT(T, 0U); 4946 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 4947 4948 // Check whether the member was user-declared. 4949 switch (member) { 4950 case CXXDefaultConstructor: 4951 if (RD->hasUserDeclaredConstructor()) { 4952 typedef CXXRecordDecl::ctor_iterator ctor_iter; 4953 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 4954 const FunctionDecl *body = 0; 4955 ci->getBody(body); 4956 if (!body || 4957 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 4958 SourceLocation CtorLoc = ci->getLocation(); 4959 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4960 return; 4961 } 4962 } 4963 4964 assert(0 && "found no user-declared constructors"); 4965 return; 4966 } 4967 break; 4968 4969 case CXXCopyConstructor: 4970 if (RD->hasUserDeclaredCopyConstructor()) { 4971 SourceLocation CtorLoc = 4972 RD->getCopyConstructor(Context, 0)->getLocation(); 4973 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4974 return; 4975 } 4976 break; 4977 4978 case CXXCopyAssignment: 4979 if (RD->hasUserDeclaredCopyAssignment()) { 4980 // FIXME: this should use the location of the copy 4981 // assignment, not the type. 4982 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 4983 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 4984 return; 4985 } 4986 break; 4987 4988 case CXXDestructor: 4989 if (RD->hasUserDeclaredDestructor()) { 4990 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 4991 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 4992 return; 4993 } 4994 break; 4995 } 4996 4997 typedef CXXRecordDecl::base_class_iterator base_iter; 4998 4999 // Virtual bases and members inhibit trivial copying/construction, 5000 // but not trivial destruction. 5001 if (member != CXXDestructor) { 5002 // Check for virtual bases. vbases includes indirect virtual bases, 5003 // so we just iterate through the direct bases. 5004 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5005 if (bi->isVirtual()) { 5006 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5007 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5008 return; 5009 } 5010 5011 // Check for virtual methods. 5012 typedef CXXRecordDecl::method_iterator meth_iter; 5013 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5014 ++mi) { 5015 if (mi->isVirtual()) { 5016 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5017 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5018 return; 5019 } 5020 } 5021 } 5022 5023 bool (CXXRecordDecl::*hasTrivial)() const; 5024 switch (member) { 5025 case CXXDefaultConstructor: 5026 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5027 case CXXCopyConstructor: 5028 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5029 case CXXCopyAssignment: 5030 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5031 case CXXDestructor: 5032 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5033 default: 5034 assert(0 && "unexpected special member"); return; 5035 } 5036 5037 // Check for nontrivial bases (and recurse). 5038 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5039 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5040 assert(BaseRT && "Don't know how to handle dependent bases"); 5041 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5042 if (!(BaseRecTy->*hasTrivial)()) { 5043 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5044 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5045 DiagnoseNontrivial(BaseRT, member); 5046 return; 5047 } 5048 } 5049 5050 // Check for nontrivial members (and recurse). 5051 typedef RecordDecl::field_iterator field_iter; 5052 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5053 ++fi) { 5054 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5055 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5056 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5057 5058 if (!(EltRD->*hasTrivial)()) { 5059 SourceLocation FLoc = (*fi)->getLocation(); 5060 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5061 DiagnoseNontrivial(EltRT, member); 5062 return; 5063 } 5064 } 5065 } 5066 5067 assert(0 && "found no explanation for non-trivial member"); 5068} 5069 5070/// TranslateIvarVisibility - Translate visibility from a token ID to an 5071/// AST enum value. 5072static ObjCIvarDecl::AccessControl 5073TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5074 switch (ivarVisibility) { 5075 default: assert(0 && "Unknown visitibility kind"); 5076 case tok::objc_private: return ObjCIvarDecl::Private; 5077 case tok::objc_public: return ObjCIvarDecl::Public; 5078 case tok::objc_protected: return ObjCIvarDecl::Protected; 5079 case tok::objc_package: return ObjCIvarDecl::Package; 5080 } 5081} 5082 5083/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5084/// in order to create an IvarDecl object for it. 5085Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5086 SourceLocation DeclStart, 5087 DeclPtrTy IntfDecl, 5088 Declarator &D, ExprTy *BitfieldWidth, 5089 tok::ObjCKeywordKind Visibility) { 5090 5091 IdentifierInfo *II = D.getIdentifier(); 5092 Expr *BitWidth = (Expr*)BitfieldWidth; 5093 SourceLocation Loc = DeclStart; 5094 if (II) Loc = D.getIdentifierLoc(); 5095 5096 // FIXME: Unnamed fields can be handled in various different ways, for 5097 // example, unnamed unions inject all members into the struct namespace! 5098 5099 DeclaratorInfo *DInfo = 0; 5100 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5101 5102 if (BitWidth) { 5103 // 6.7.2.1p3, 6.7.2.1p4 5104 if (VerifyBitField(Loc, II, T, BitWidth)) { 5105 D.setInvalidType(); 5106 DeleteExpr(BitWidth); 5107 BitWidth = 0; 5108 } 5109 } else { 5110 // Not a bitfield. 5111 5112 // validate II. 5113 5114 } 5115 5116 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5117 // than a variably modified type. 5118 if (T->isVariablyModifiedType()) { 5119 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5120 D.setInvalidType(); 5121 } 5122 5123 // Get the visibility (access control) for this ivar. 5124 ObjCIvarDecl::AccessControl ac = 5125 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5126 : ObjCIvarDecl::None; 5127 // Must set ivar's DeclContext to its enclosing interface. 5128 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5129 DeclContext *EnclosingContext; 5130 if (ObjCImplementationDecl *IMPDecl = 5131 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5132 // Case of ivar declared in an implementation. Context is that of its class. 5133 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5134 assert(IDecl && "No class- ActOnIvar"); 5135 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5136 } else 5137 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5138 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5139 5140 // Construct the decl. 5141 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5142 EnclosingContext, Loc, II, T, 5143 DInfo, ac, (Expr *)BitfieldWidth); 5144 5145 if (II) { 5146 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, true); 5147 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5148 && !isa<TagDecl>(PrevDecl)) { 5149 Diag(Loc, diag::err_duplicate_member) << II; 5150 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5151 NewID->setInvalidDecl(); 5152 } 5153 } 5154 5155 // Process attributes attached to the ivar. 5156 ProcessDeclAttributes(S, NewID, D); 5157 5158 if (D.isInvalidType()) 5159 NewID->setInvalidDecl(); 5160 5161 if (II) { 5162 // FIXME: When interfaces are DeclContexts, we'll need to add 5163 // these to the interface. 5164 S->AddDecl(DeclPtrTy::make(NewID)); 5165 IdResolver.AddDecl(NewID); 5166 } 5167 5168 return DeclPtrTy::make(NewID); 5169} 5170 5171void Sema::ActOnFields(Scope* S, 5172 SourceLocation RecLoc, DeclPtrTy RecDecl, 5173 DeclPtrTy *Fields, unsigned NumFields, 5174 SourceLocation LBrac, SourceLocation RBrac, 5175 AttributeList *Attr) { 5176 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5177 assert(EnclosingDecl && "missing record or interface decl"); 5178 5179 // If the decl this is being inserted into is invalid, then it may be a 5180 // redeclaration or some other bogus case. Don't try to add fields to it. 5181 if (EnclosingDecl->isInvalidDecl()) { 5182 // FIXME: Deallocate fields? 5183 return; 5184 } 5185 5186 5187 // Verify that all the fields are okay. 5188 unsigned NumNamedMembers = 0; 5189 llvm::SmallVector<FieldDecl*, 32> RecFields; 5190 5191 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5192 for (unsigned i = 0; i != NumFields; ++i) { 5193 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5194 5195 // Get the type for the field. 5196 Type *FDTy = FD->getType().getTypePtr(); 5197 5198 if (!FD->isAnonymousStructOrUnion()) { 5199 // Remember all fields written by the user. 5200 RecFields.push_back(FD); 5201 } 5202 5203 // If the field is already invalid for some reason, don't emit more 5204 // diagnostics about it. 5205 if (FD->isInvalidDecl()) 5206 continue; 5207 5208 // C99 6.7.2.1p2: 5209 // A structure or union shall not contain a member with 5210 // incomplete or function type (hence, a structure shall not 5211 // contain an instance of itself, but may contain a pointer to 5212 // an instance of itself), except that the last member of a 5213 // structure with more than one named member may have incomplete 5214 // array type; such a structure (and any union containing, 5215 // possibly recursively, a member that is such a structure) 5216 // shall not be a member of a structure or an element of an 5217 // array. 5218 if (FDTy->isFunctionType()) { 5219 // Field declared as a function. 5220 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5221 << FD->getDeclName(); 5222 FD->setInvalidDecl(); 5223 EnclosingDecl->setInvalidDecl(); 5224 continue; 5225 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5226 Record && Record->isStruct()) { 5227 // Flexible array member. 5228 if (NumNamedMembers < 1) { 5229 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5230 << FD->getDeclName(); 5231 FD->setInvalidDecl(); 5232 EnclosingDecl->setInvalidDecl(); 5233 continue; 5234 } 5235 // Okay, we have a legal flexible array member at the end of the struct. 5236 if (Record) 5237 Record->setHasFlexibleArrayMember(true); 5238 } else if (!FDTy->isDependentType() && 5239 RequireCompleteType(FD->getLocation(), FD->getType(), 5240 diag::err_field_incomplete)) { 5241 // Incomplete type 5242 FD->setInvalidDecl(); 5243 EnclosingDecl->setInvalidDecl(); 5244 continue; 5245 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5246 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5247 // If this is a member of a union, then entire union becomes "flexible". 5248 if (Record && Record->isUnion()) { 5249 Record->setHasFlexibleArrayMember(true); 5250 } else { 5251 // If this is a struct/class and this is not the last element, reject 5252 // it. Note that GCC supports variable sized arrays in the middle of 5253 // structures. 5254 if (i != NumFields-1) 5255 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5256 << FD->getDeclName() << FD->getType(); 5257 else { 5258 // We support flexible arrays at the end of structs in 5259 // other structs as an extension. 5260 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5261 << FD->getDeclName(); 5262 if (Record) 5263 Record->setHasFlexibleArrayMember(true); 5264 } 5265 } 5266 } 5267 if (Record && FDTTy->getDecl()->hasObjectMember()) 5268 Record->setHasObjectMember(true); 5269 } else if (FDTy->isObjCInterfaceType()) { 5270 /// A field cannot be an Objective-c object 5271 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5272 FD->setInvalidDecl(); 5273 EnclosingDecl->setInvalidDecl(); 5274 continue; 5275 } else if (getLangOptions().ObjC1 && 5276 getLangOptions().getGCMode() != LangOptions::NonGC && 5277 Record && 5278 (FD->getType()->isObjCObjectPointerType() || 5279 FD->getType().isObjCGCStrong())) 5280 Record->setHasObjectMember(true); 5281 // Keep track of the number of named members. 5282 if (FD->getIdentifier()) 5283 ++NumNamedMembers; 5284 } 5285 5286 // Okay, we successfully defined 'Record'. 5287 if (Record) { 5288 Record->completeDefinition(Context); 5289 } else { 5290 ObjCIvarDecl **ClsFields = 5291 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5292 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5293 ID->setIVarList(ClsFields, RecFields.size(), Context); 5294 ID->setLocEnd(RBrac); 5295 // Add ivar's to class's DeclContext. 5296 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5297 ClsFields[i]->setLexicalDeclContext(ID); 5298 ID->addDecl(ClsFields[i]); 5299 } 5300 // Must enforce the rule that ivars in the base classes may not be 5301 // duplicates. 5302 if (ID->getSuperClass()) { 5303 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5304 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5305 ObjCIvarDecl* Ivar = (*IVI); 5306 5307 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5308 ObjCIvarDecl* prevIvar = 5309 ID->getSuperClass()->lookupInstanceVariable(II); 5310 if (prevIvar) { 5311 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5312 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5313 } 5314 } 5315 } 5316 } 5317 } else if (ObjCImplementationDecl *IMPDecl = 5318 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5319 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5320 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5321 // Ivar declared in @implementation never belongs to the implementation. 5322 // Only it is in implementation's lexical context. 5323 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5324 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5325 } 5326 } 5327 5328 if (Attr) 5329 ProcessDeclAttributeList(S, Record, Attr); 5330} 5331 5332EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5333 EnumConstantDecl *LastEnumConst, 5334 SourceLocation IdLoc, 5335 IdentifierInfo *Id, 5336 ExprArg val) { 5337 Expr *Val = (Expr *)val.get(); 5338 5339 llvm::APSInt EnumVal(32); 5340 QualType EltTy; 5341 if (Val && !Val->isTypeDependent()) { 5342 // Make sure to promote the operand type to int. 5343 UsualUnaryConversions(Val); 5344 if (Val != val.get()) { 5345 val.release(); 5346 val = Val; 5347 } 5348 5349 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5350 SourceLocation ExpLoc; 5351 if (!Val->isValueDependent() && 5352 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5353 Val = 0; 5354 } else { 5355 EltTy = Val->getType(); 5356 } 5357 } 5358 5359 if (!Val) { 5360 if (LastEnumConst) { 5361 // Assign the last value + 1. 5362 EnumVal = LastEnumConst->getInitVal(); 5363 ++EnumVal; 5364 5365 // Check for overflow on increment. 5366 if (EnumVal < LastEnumConst->getInitVal()) 5367 Diag(IdLoc, diag::warn_enum_value_overflow); 5368 5369 EltTy = LastEnumConst->getType(); 5370 } else { 5371 // First value, set to zero. 5372 EltTy = Context.IntTy; 5373 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5374 } 5375 } 5376 5377 val.release(); 5378 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5379 Val, EnumVal); 5380} 5381 5382 5383Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5384 DeclPtrTy lastEnumConst, 5385 SourceLocation IdLoc, 5386 IdentifierInfo *Id, 5387 SourceLocation EqualLoc, ExprTy *val) { 5388 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5389 EnumConstantDecl *LastEnumConst = 5390 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5391 Expr *Val = static_cast<Expr*>(val); 5392 5393 // The scope passed in may not be a decl scope. Zip up the scope tree until 5394 // we find one that is. 5395 S = getNonFieldDeclScope(S); 5396 5397 // Verify that there isn't already something declared with this name in this 5398 // scope. 5399 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5400 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5401 // Maybe we will complain about the shadowed template parameter. 5402 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5403 // Just pretend that we didn't see the previous declaration. 5404 PrevDecl = 0; 5405 } 5406 5407 if (PrevDecl) { 5408 // When in C++, we may get a TagDecl with the same name; in this case the 5409 // enum constant will 'hide' the tag. 5410 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5411 "Received TagDecl when not in C++!"); 5412 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5413 if (isa<EnumConstantDecl>(PrevDecl)) 5414 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5415 else 5416 Diag(IdLoc, diag::err_redefinition) << Id; 5417 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5418 if (Val) Val->Destroy(Context); 5419 return DeclPtrTy(); 5420 } 5421 } 5422 5423 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5424 IdLoc, Id, Owned(Val)); 5425 5426 // Register this decl in the current scope stack. 5427 if (New) 5428 PushOnScopeChains(New, S); 5429 5430 return DeclPtrTy::make(New); 5431} 5432 5433void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5434 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5435 DeclPtrTy *Elements, unsigned NumElements, 5436 Scope *S, AttributeList *Attr) { 5437 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5438 QualType EnumType = Context.getTypeDeclType(Enum); 5439 5440 if (Attr) 5441 ProcessDeclAttributeList(S, Enum, Attr); 5442 5443 // TODO: If the result value doesn't fit in an int, it must be a long or long 5444 // long value. ISO C does not support this, but GCC does as an extension, 5445 // emit a warning. 5446 unsigned IntWidth = Context.Target.getIntWidth(); 5447 unsigned CharWidth = Context.Target.getCharWidth(); 5448 unsigned ShortWidth = Context.Target.getShortWidth(); 5449 5450 // Verify that all the values are okay, compute the size of the values, and 5451 // reverse the list. 5452 unsigned NumNegativeBits = 0; 5453 unsigned NumPositiveBits = 0; 5454 5455 // Keep track of whether all elements have type int. 5456 bool AllElementsInt = true; 5457 5458 for (unsigned i = 0; i != NumElements; ++i) { 5459 EnumConstantDecl *ECD = 5460 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5461 if (!ECD) continue; // Already issued a diagnostic. 5462 5463 // If the enum value doesn't fit in an int, emit an extension warning. 5464 const llvm::APSInt &InitVal = ECD->getInitVal(); 5465 assert(InitVal.getBitWidth() >= IntWidth && 5466 "Should have promoted value to int"); 5467 if (InitVal.getBitWidth() > IntWidth) { 5468 llvm::APSInt V(InitVal); 5469 V.trunc(IntWidth); 5470 V.extend(InitVal.getBitWidth()); 5471 if (V != InitVal) 5472 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5473 << InitVal.toString(10); 5474 } 5475 5476 // Keep track of the size of positive and negative values. 5477 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5478 NumPositiveBits = std::max(NumPositiveBits, 5479 (unsigned)InitVal.getActiveBits()); 5480 else 5481 NumNegativeBits = std::max(NumNegativeBits, 5482 (unsigned)InitVal.getMinSignedBits()); 5483 5484 // Keep track of whether every enum element has type int (very commmon). 5485 if (AllElementsInt) 5486 AllElementsInt = ECD->getType() == Context.IntTy; 5487 } 5488 5489 // Figure out the type that should be used for this enum. 5490 // FIXME: Support -fshort-enums. 5491 QualType BestType; 5492 unsigned BestWidth; 5493 5494 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5495 5496 if (NumNegativeBits) { 5497 // If there is a negative value, figure out the smallest integer type (of 5498 // int/long/longlong) that fits. 5499 // If it's packed, check also if it fits a char or a short. 5500 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5501 BestType = Context.SignedCharTy; 5502 BestWidth = CharWidth; 5503 } else if (Packed && NumNegativeBits <= ShortWidth && 5504 NumPositiveBits < ShortWidth) { 5505 BestType = Context.ShortTy; 5506 BestWidth = ShortWidth; 5507 } 5508 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5509 BestType = Context.IntTy; 5510 BestWidth = IntWidth; 5511 } else { 5512 BestWidth = Context.Target.getLongWidth(); 5513 5514 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5515 BestType = Context.LongTy; 5516 else { 5517 BestWidth = Context.Target.getLongLongWidth(); 5518 5519 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5520 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5521 BestType = Context.LongLongTy; 5522 } 5523 } 5524 } else { 5525 // If there is no negative value, figure out which of uint, ulong, ulonglong 5526 // fits. 5527 // If it's packed, check also if it fits a char or a short. 5528 if (Packed && NumPositiveBits <= CharWidth) { 5529 BestType = Context.UnsignedCharTy; 5530 BestWidth = CharWidth; 5531 } else if (Packed && NumPositiveBits <= ShortWidth) { 5532 BestType = Context.UnsignedShortTy; 5533 BestWidth = ShortWidth; 5534 } 5535 else if (NumPositiveBits <= IntWidth) { 5536 BestType = Context.UnsignedIntTy; 5537 BestWidth = IntWidth; 5538 } else if (NumPositiveBits <= 5539 (BestWidth = Context.Target.getLongWidth())) { 5540 BestType = Context.UnsignedLongTy; 5541 } else { 5542 BestWidth = Context.Target.getLongLongWidth(); 5543 assert(NumPositiveBits <= BestWidth && 5544 "How could an initializer get larger than ULL?"); 5545 BestType = Context.UnsignedLongLongTy; 5546 } 5547 } 5548 5549 // Loop over all of the enumerator constants, changing their types to match 5550 // the type of the enum if needed. 5551 for (unsigned i = 0; i != NumElements; ++i) { 5552 EnumConstantDecl *ECD = 5553 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5554 if (!ECD) continue; // Already issued a diagnostic. 5555 5556 // Standard C says the enumerators have int type, but we allow, as an 5557 // extension, the enumerators to be larger than int size. If each 5558 // enumerator value fits in an int, type it as an int, otherwise type it the 5559 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5560 // that X has type 'int', not 'unsigned'. 5561 if (ECD->getType() == Context.IntTy) { 5562 // Make sure the init value is signed. 5563 llvm::APSInt IV = ECD->getInitVal(); 5564 IV.setIsSigned(true); 5565 ECD->setInitVal(IV); 5566 5567 if (getLangOptions().CPlusPlus) 5568 // C++ [dcl.enum]p4: Following the closing brace of an 5569 // enum-specifier, each enumerator has the type of its 5570 // enumeration. 5571 ECD->setType(EnumType); 5572 continue; // Already int type. 5573 } 5574 5575 // Determine whether the value fits into an int. 5576 llvm::APSInt InitVal = ECD->getInitVal(); 5577 bool FitsInInt; 5578 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5579 FitsInInt = InitVal.getActiveBits() < IntWidth; 5580 else 5581 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5582 5583 // If it fits into an integer type, force it. Otherwise force it to match 5584 // the enum decl type. 5585 QualType NewTy; 5586 unsigned NewWidth; 5587 bool NewSign; 5588 if (FitsInInt) { 5589 NewTy = Context.IntTy; 5590 NewWidth = IntWidth; 5591 NewSign = true; 5592 } else if (ECD->getType() == BestType) { 5593 // Already the right type! 5594 if (getLangOptions().CPlusPlus) 5595 // C++ [dcl.enum]p4: Following the closing brace of an 5596 // enum-specifier, each enumerator has the type of its 5597 // enumeration. 5598 ECD->setType(EnumType); 5599 continue; 5600 } else { 5601 NewTy = BestType; 5602 NewWidth = BestWidth; 5603 NewSign = BestType->isSignedIntegerType(); 5604 } 5605 5606 // Adjust the APSInt value. 5607 InitVal.extOrTrunc(NewWidth); 5608 InitVal.setIsSigned(NewSign); 5609 ECD->setInitVal(InitVal); 5610 5611 // Adjust the Expr initializer and type. 5612 if (ECD->getInitExpr()) 5613 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5614 CastExpr::CK_IntegralCast, 5615 ECD->getInitExpr(), 5616 /*isLvalue=*/false)); 5617 if (getLangOptions().CPlusPlus) 5618 // C++ [dcl.enum]p4: Following the closing brace of an 5619 // enum-specifier, each enumerator has the type of its 5620 // enumeration. 5621 ECD->setType(EnumType); 5622 else 5623 ECD->setType(NewTy); 5624 } 5625 5626 Enum->completeDefinition(Context, BestType); 5627} 5628 5629Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5630 ExprArg expr) { 5631 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5632 5633 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5634 Loc, AsmString); 5635 CurContext->addDecl(New); 5636 return DeclPtrTy::make(New); 5637} 5638 5639void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5640 SourceLocation PragmaLoc, 5641 SourceLocation NameLoc) { 5642 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5643 5644 if (PrevDecl) { 5645 PrevDecl->addAttr(::new (Context) WeakAttr()); 5646 } else { 5647 (void)WeakUndeclaredIdentifiers.insert( 5648 std::pair<IdentifierInfo*,WeakInfo> 5649 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5650 } 5651} 5652 5653void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5654 IdentifierInfo* AliasName, 5655 SourceLocation PragmaLoc, 5656 SourceLocation NameLoc, 5657 SourceLocation AliasNameLoc) { 5658 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5659 WeakInfo W = WeakInfo(Name, NameLoc); 5660 5661 if (PrevDecl) { 5662 if (!PrevDecl->hasAttr<AliasAttr>()) 5663 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5664 DeclApplyPragmaWeak(TUScope, ND, W); 5665 } else { 5666 (void)WeakUndeclaredIdentifiers.insert( 5667 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5668 } 5669} 5670