SemaDecl.cpp revision 6e4750188e836e119f8605cbd34023d0a3b18011
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/AST/DeclObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/Parse/DeclSpec.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31using namespace clang; 32 33/// getDeclName - Return a pretty name for the specified decl if possible, or 34/// an empty string if not. This is used for pretty crash reporting. 35std::string Sema::getDeclName(DeclPtrTy d) { 36 Decl *D = d.getAs<Decl>(); 37 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 38 return DN->getQualifiedNameAsString(); 39 return ""; 40} 41 42Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 43 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 44} 45 46/// \brief If the identifier refers to a type name within this scope, 47/// return the declaration of that type. 48/// 49/// This routine performs ordinary name lookup of the identifier II 50/// within the given scope, with optional C++ scope specifier SS, to 51/// determine whether the name refers to a type. If so, returns an 52/// opaque pointer (actually a QualType) corresponding to that 53/// type. Otherwise, returns NULL. 54/// 55/// If name lookup results in an ambiguity, this routine will complain 56/// and then return NULL. 57Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 58 Scope *S, const CXXScopeSpec *SS) { 59 // C++ [temp.res]p3: 60 // A qualified-id that refers to a type and in which the 61 // nested-name-specifier depends on a template-parameter (14.6.2) 62 // shall be prefixed by the keyword typename to indicate that the 63 // qualified-id denotes a type, forming an 64 // elaborated-type-specifier (7.1.5.3). 65 // 66 // We therefore do not perform any name lookup up SS is a dependent 67 // scope name. FIXME: we will need to perform a special kind of 68 // lookup if the scope specifier names a member of the current 69 // instantiation. 70 if (SS && isDependentScopeSpecifier(*SS)) 71 return 0; 72 73 NamedDecl *IIDecl = 0; 74 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 75 false, false); 76 switch (Result.getKind()) { 77 case LookupResult::NotFound: 78 case LookupResult::FoundOverloaded: 79 return 0; 80 81 case LookupResult::AmbiguousBaseSubobjectTypes: 82 case LookupResult::AmbiguousBaseSubobjects: 83 case LookupResult::AmbiguousReference: { 84 // Look to see if we have a type anywhere in the list of results. 85 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 86 Res != ResEnd; ++Res) { 87 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 88 if (!IIDecl || 89 (*Res)->getLocation().getRawEncoding() < 90 IIDecl->getLocation().getRawEncoding()) 91 IIDecl = *Res; 92 } 93 } 94 95 if (!IIDecl) { 96 // None of the entities we found is a type, so there is no way 97 // to even assume that the result is a type. In this case, don't 98 // complain about the ambiguity. The parser will either try to 99 // perform this lookup again (e.g., as an object name), which 100 // will produce the ambiguity, or will complain that it expected 101 // a type name. 102 Result.Destroy(); 103 return 0; 104 } 105 106 // We found a type within the ambiguous lookup; diagnose the 107 // ambiguity and then return that type. This might be the right 108 // answer, or it might not be, but it suppresses any attempt to 109 // perform the name lookup again. 110 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 111 break; 112 } 113 114 case LookupResult::Found: 115 IIDecl = Result.getAsDecl(); 116 break; 117 } 118 119 if (IIDecl) { 120 QualType T; 121 122 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 123 // Check whether we can use this type 124 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 125 126 T = Context.getTypeDeclType(TD); 127 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 128 // Check whether we can use this interface. 129 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 130 131 T = Context.getObjCInterfaceType(IDecl); 132 } else 133 return 0; 134 135 if (SS) 136 T = getQualifiedNameType(*SS, T); 137 138 return T.getAsOpaquePtr(); 139 } 140 141 return 0; 142} 143 144/// isTagName() - This method is called *for error recovery purposes only* 145/// to determine if the specified name is a valid tag name ("struct foo"). If 146/// so, this returns the TST for the tag corresponding to it (TST_enum, 147/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 148/// where the user forgot to specify the tag. 149DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 150 // Do a tag name lookup in this scope. 151 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 152 if (R.getKind() == LookupResult::Found) 153 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 154 switch (TD->getTagKind()) { 155 case TagDecl::TK_struct: return DeclSpec::TST_struct; 156 case TagDecl::TK_union: return DeclSpec::TST_union; 157 case TagDecl::TK_class: return DeclSpec::TST_class; 158 case TagDecl::TK_enum: return DeclSpec::TST_enum; 159 } 160 } 161 162 return DeclSpec::TST_unspecified; 163} 164 165 166 167DeclContext *Sema::getContainingDC(DeclContext *DC) { 168 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 169 // A C++ out-of-line method will return to the file declaration context. 170 if (MD->isOutOfLineDefinition()) 171 return MD->getLexicalDeclContext(); 172 173 // A C++ inline method is parsed *after* the topmost class it was declared 174 // in is fully parsed (it's "complete"). 175 // The parsing of a C++ inline method happens at the declaration context of 176 // the topmost (non-nested) class it is lexically declared in. 177 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 178 DC = MD->getParent(); 179 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 180 DC = RD; 181 182 // Return the declaration context of the topmost class the inline method is 183 // declared in. 184 return DC; 185 } 186 187 if (isa<ObjCMethodDecl>(DC)) 188 return Context.getTranslationUnitDecl(); 189 190 return DC->getLexicalParent(); 191} 192 193void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 194 assert(getContainingDC(DC) == CurContext && 195 "The next DeclContext should be lexically contained in the current one."); 196 CurContext = DC; 197 S->setEntity(DC); 198} 199 200void Sema::PopDeclContext() { 201 assert(CurContext && "DeclContext imbalance!"); 202 203 CurContext = getContainingDC(CurContext); 204} 205 206/// \brief Determine whether we allow overloading of the function 207/// PrevDecl with another declaration. 208/// 209/// This routine determines whether overloading is possible, not 210/// whether some new function is actually an overload. It will return 211/// true in C++ (where we can always provide overloads) or, as an 212/// extension, in C when the previous function is already an 213/// overloaded function declaration or has the "overloadable" 214/// attribute. 215static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 216 if (Context.getLangOptions().CPlusPlus) 217 return true; 218 219 if (isa<OverloadedFunctionDecl>(PrevDecl)) 220 return true; 221 222 return PrevDecl->getAttr<OverloadableAttr>() != 0; 223} 224 225/// Add this decl to the scope shadowed decl chains. 226void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 227 // Move up the scope chain until we find the nearest enclosing 228 // non-transparent context. The declaration will be introduced into this 229 // scope. 230 while (S->getEntity() && 231 ((DeclContext *)S->getEntity())->isTransparentContext()) 232 S = S->getParent(); 233 234 S->AddDecl(DeclPtrTy::make(D)); 235 236 // Add scoped declarations into their context, so that they can be 237 // found later. Declarations without a context won't be inserted 238 // into any context. 239 CurContext->addDecl(Context, D); 240 241 // C++ [basic.scope]p4: 242 // -- exactly one declaration shall declare a class name or 243 // enumeration name that is not a typedef name and the other 244 // declarations shall all refer to the same object or 245 // enumerator, or all refer to functions and function templates; 246 // in this case the class name or enumeration name is hidden. 247 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 248 // We are pushing the name of a tag (enum or class). 249 if (CurContext->getLookupContext() 250 == TD->getDeclContext()->getLookupContext()) { 251 // We're pushing the tag into the current context, which might 252 // require some reshuffling in the identifier resolver. 253 IdentifierResolver::iterator 254 I = IdResolver.begin(TD->getDeclName()), 255 IEnd = IdResolver.end(); 256 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 257 NamedDecl *PrevDecl = *I; 258 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 259 PrevDecl = *I, ++I) { 260 if (TD->declarationReplaces(*I)) { 261 // This is a redeclaration. Remove it from the chain and 262 // break out, so that we'll add in the shadowed 263 // declaration. 264 S->RemoveDecl(DeclPtrTy::make(*I)); 265 if (PrevDecl == *I) { 266 IdResolver.RemoveDecl(*I); 267 IdResolver.AddDecl(TD); 268 return; 269 } else { 270 IdResolver.RemoveDecl(*I); 271 break; 272 } 273 } 274 } 275 276 // There is already a declaration with the same name in the same 277 // scope, which is not a tag declaration. It must be found 278 // before we find the new declaration, so insert the new 279 // declaration at the end of the chain. 280 IdResolver.AddShadowedDecl(TD, PrevDecl); 281 282 return; 283 } 284 } 285 } else if (isa<FunctionDecl>(D) && 286 AllowOverloadingOfFunction(D, Context)) { 287 // We are pushing the name of a function, which might be an 288 // overloaded name. 289 FunctionDecl *FD = cast<FunctionDecl>(D); 290 IdentifierResolver::iterator Redecl 291 = std::find_if(IdResolver.begin(FD->getDeclName()), 292 IdResolver.end(), 293 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 294 FD)); 295 if (Redecl != IdResolver.end() && 296 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 297 // There is already a declaration of a function on our 298 // IdResolver chain. Replace it with this declaration. 299 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 300 IdResolver.RemoveDecl(*Redecl); 301 } 302 } else if (isa<ObjCInterfaceDecl>(D)) { 303 // We're pushing an Objective-C interface into the current 304 // context. If there is already an alias declaration, remove it first. 305 for (IdentifierResolver::iterator 306 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 307 I != IEnd; ++I) { 308 if (isa<ObjCCompatibleAliasDecl>(*I)) { 309 S->RemoveDecl(DeclPtrTy::make(*I)); 310 IdResolver.RemoveDecl(*I); 311 break; 312 } 313 } 314 } 315 316 IdResolver.AddDecl(D); 317} 318 319void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 320 if (S->decl_empty()) return; 321 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 322 "Scope shouldn't contain decls!"); 323 324 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 325 I != E; ++I) { 326 Decl *TmpD = (*I).getAs<Decl>(); 327 assert(TmpD && "This decl didn't get pushed??"); 328 329 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 330 NamedDecl *D = cast<NamedDecl>(TmpD); 331 332 if (!D->getDeclName()) continue; 333 334 // Remove this name from our lexical scope. 335 IdResolver.RemoveDecl(D); 336 } 337} 338 339/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 340/// return 0 if one not found. 341ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 342 // The third "scope" argument is 0 since we aren't enabling lazy built-in 343 // creation from this context. 344 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 345 346 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 347} 348 349/// getNonFieldDeclScope - Retrieves the innermost scope, starting 350/// from S, where a non-field would be declared. This routine copes 351/// with the difference between C and C++ scoping rules in structs and 352/// unions. For example, the following code is well-formed in C but 353/// ill-formed in C++: 354/// @code 355/// struct S6 { 356/// enum { BAR } e; 357/// }; 358/// 359/// void test_S6() { 360/// struct S6 a; 361/// a.e = BAR; 362/// } 363/// @endcode 364/// For the declaration of BAR, this routine will return a different 365/// scope. The scope S will be the scope of the unnamed enumeration 366/// within S6. In C++, this routine will return the scope associated 367/// with S6, because the enumeration's scope is a transparent 368/// context but structures can contain non-field names. In C, this 369/// routine will return the translation unit scope, since the 370/// enumeration's scope is a transparent context and structures cannot 371/// contain non-field names. 372Scope *Sema::getNonFieldDeclScope(Scope *S) { 373 while (((S->getFlags() & Scope::DeclScope) == 0) || 374 (S->getEntity() && 375 ((DeclContext *)S->getEntity())->isTransparentContext()) || 376 (S->isClassScope() && !getLangOptions().CPlusPlus)) 377 S = S->getParent(); 378 return S; 379} 380 381void Sema::InitBuiltinVaListType() { 382 if (!Context.getBuiltinVaListType().isNull()) 383 return; 384 385 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 386 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 387 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 388 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 389} 390 391/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 392/// file scope. lazily create a decl for it. ForRedeclaration is true 393/// if we're creating this built-in in anticipation of redeclaring the 394/// built-in. 395NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 396 Scope *S, bool ForRedeclaration, 397 SourceLocation Loc) { 398 Builtin::ID BID = (Builtin::ID)bid; 399 400 if (Context.BuiltinInfo.hasVAListUse(BID)) 401 InitBuiltinVaListType(); 402 403 Builtin::Context::GetBuiltinTypeError Error; 404 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 405 switch (Error) { 406 case Builtin::Context::GE_None: 407 // Okay 408 break; 409 410 case Builtin::Context::GE_Missing_FILE: 411 if (ForRedeclaration) 412 Diag(Loc, diag::err_implicit_decl_requires_stdio) 413 << Context.BuiltinInfo.GetName(BID); 414 return 0; 415 } 416 417 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 418 Diag(Loc, diag::ext_implicit_lib_function_decl) 419 << Context.BuiltinInfo.GetName(BID) 420 << R; 421 if (Context.BuiltinInfo.getHeaderName(BID) && 422 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 423 != Diagnostic::Ignored) 424 Diag(Loc, diag::note_please_include_header) 425 << Context.BuiltinInfo.getHeaderName(BID) 426 << Context.BuiltinInfo.GetName(BID); 427 } 428 429 FunctionDecl *New = FunctionDecl::Create(Context, 430 Context.getTranslationUnitDecl(), 431 Loc, II, R, 432 FunctionDecl::Extern, false, 433 /*hasPrototype=*/true); 434 New->setImplicit(); 435 436 // Create Decl objects for each parameter, adding them to the 437 // FunctionDecl. 438 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 439 llvm::SmallVector<ParmVarDecl*, 16> Params; 440 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 441 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 442 FT->getArgType(i), VarDecl::None, 0)); 443 New->setParams(Context, &Params[0], Params.size()); 444 } 445 446 AddKnownFunctionAttributes(New); 447 448 // TUScope is the translation-unit scope to insert this function into. 449 // FIXME: This is hideous. We need to teach PushOnScopeChains to 450 // relate Scopes to DeclContexts, and probably eliminate CurContext 451 // entirely, but we're not there yet. 452 DeclContext *SavedContext = CurContext; 453 CurContext = Context.getTranslationUnitDecl(); 454 PushOnScopeChains(New, TUScope); 455 CurContext = SavedContext; 456 return New; 457} 458 459/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 460/// everything from the standard library is defined. 461NamespaceDecl *Sema::GetStdNamespace() { 462 if (!StdNamespace) { 463 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 464 DeclContext *Global = Context.getTranslationUnitDecl(); 465 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 466 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 467 } 468 return StdNamespace; 469} 470 471/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 472/// same name and scope as a previous declaration 'Old'. Figure out 473/// how to resolve this situation, merging decls or emitting 474/// diagnostics as appropriate. If there was an error, set New to be invalid. 475/// 476void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 477 // If either decl is known invalid already, set the new one to be invalid and 478 // don't bother doing any merging checks. 479 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 480 return New->setInvalidDecl(); 481 482 bool objc_types = false; 483 484 // Allow multiple definitions for ObjC built-in typedefs. 485 // FIXME: Verify the underlying types are equivalent! 486 if (getLangOptions().ObjC1) { 487 const IdentifierInfo *TypeID = New->getIdentifier(); 488 switch (TypeID->getLength()) { 489 default: break; 490 case 2: 491 if (!TypeID->isStr("id")) 492 break; 493 Context.setObjCIdType(Context.getTypeDeclType(New)); 494 objc_types = true; 495 break; 496 case 5: 497 if (!TypeID->isStr("Class")) 498 break; 499 Context.setObjCClassType(Context.getTypeDeclType(New)); 500 return; 501 case 3: 502 if (!TypeID->isStr("SEL")) 503 break; 504 Context.setObjCSelType(Context.getTypeDeclType(New)); 505 return; 506 case 8: 507 if (!TypeID->isStr("Protocol")) 508 break; 509 Context.setObjCProtoType(New->getUnderlyingType()); 510 return; 511 } 512 // Fall through - the typedef name was not a builtin type. 513 } 514 // Verify the old decl was also a type. 515 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 516 if (!Old) { 517 Diag(New->getLocation(), diag::err_redefinition_different_kind) 518 << New->getDeclName(); 519 if (OldD->getLocation().isValid()) 520 Diag(OldD->getLocation(), diag::note_previous_definition); 521 return New->setInvalidDecl(); 522 } 523 524 // Determine the "old" type we'll use for checking and diagnostics. 525 QualType OldType; 526 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 527 OldType = OldTypedef->getUnderlyingType(); 528 else 529 OldType = Context.getTypeDeclType(Old); 530 531 // If the typedef types are not identical, reject them in all languages and 532 // with any extensions enabled. 533 534 if (OldType != New->getUnderlyingType() && 535 Context.getCanonicalType(OldType) != 536 Context.getCanonicalType(New->getUnderlyingType())) { 537 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 538 << New->getUnderlyingType() << OldType; 539 if (Old->getLocation().isValid()) 540 Diag(Old->getLocation(), diag::note_previous_definition); 541 return New->setInvalidDecl(); 542 } 543 544 if (objc_types || getLangOptions().Microsoft) 545 return; 546 547 // C++ [dcl.typedef]p2: 548 // In a given non-class scope, a typedef specifier can be used to 549 // redefine the name of any type declared in that scope to refer 550 // to the type to which it already refers. 551 if (getLangOptions().CPlusPlus) { 552 if (!isa<CXXRecordDecl>(CurContext)) 553 return; 554 Diag(New->getLocation(), diag::err_redefinition) 555 << New->getDeclName(); 556 Diag(Old->getLocation(), diag::note_previous_definition); 557 return New->setInvalidDecl(); 558 } 559 560 // If we have a redefinition of a typedef in C, emit a warning. This warning 561 // is normally mapped to an error, but can be controlled with 562 // -Wtypedef-redefinition. 563 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 564 << New->getDeclName(); 565 Diag(Old->getLocation(), diag::note_previous_definition); 566 return; 567} 568 569/// DeclhasAttr - returns true if decl Declaration already has the target 570/// attribute. 571static bool DeclHasAttr(const Decl *decl, const Attr *target) { 572 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 573 if (attr->getKind() == target->getKind()) 574 return true; 575 576 return false; 577} 578 579/// MergeAttributes - append attributes from the Old decl to the New one. 580static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 581 Attr *attr = const_cast<Attr*>(Old->getAttrs()); 582 583 while (attr) { 584 Attr *tmp = attr; 585 attr = attr->getNext(); 586 587 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 588 tmp->setInherited(true); 589 New->addAttr(tmp); 590 } else { 591 tmp->setNext(0); 592 tmp->Destroy(C); 593 } 594 } 595 596 Old->invalidateAttrs(); 597} 598 599/// Used in MergeFunctionDecl to keep track of function parameters in 600/// C. 601struct GNUCompatibleParamWarning { 602 ParmVarDecl *OldParm; 603 ParmVarDecl *NewParm; 604 QualType PromotedType; 605}; 606 607/// MergeFunctionDecl - We just parsed a function 'New' from 608/// declarator D which has the same name and scope as a previous 609/// declaration 'Old'. Figure out how to resolve this situation, 610/// merging decls or emitting diagnostics as appropriate. 611/// 612/// In C++, New and Old must be declarations that are not 613/// overloaded. Use IsOverload to determine whether New and Old are 614/// overloaded, and to select the Old declaration that New should be 615/// merged with. 616/// 617/// Returns true if there was an error, false otherwise. 618bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 619 assert(!isa<OverloadedFunctionDecl>(OldD) && 620 "Cannot merge with an overloaded function declaration"); 621 622 // Verify the old decl was also a function. 623 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 624 if (!Old) { 625 Diag(New->getLocation(), diag::err_redefinition_different_kind) 626 << New->getDeclName(); 627 Diag(OldD->getLocation(), diag::note_previous_definition); 628 return true; 629 } 630 631 // Determine whether the previous declaration was a definition, 632 // implicit declaration, or a declaration. 633 diag::kind PrevDiag; 634 if (Old->isThisDeclarationADefinition()) 635 PrevDiag = diag::note_previous_definition; 636 else if (Old->isImplicit()) 637 PrevDiag = diag::note_previous_implicit_declaration; 638 else 639 PrevDiag = diag::note_previous_declaration; 640 641 QualType OldQType = Context.getCanonicalType(Old->getType()); 642 QualType NewQType = Context.getCanonicalType(New->getType()); 643 644 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 645 New->getStorageClass() == FunctionDecl::Static && 646 Old->getStorageClass() != FunctionDecl::Static) { 647 Diag(New->getLocation(), diag::err_static_non_static) 648 << New; 649 Diag(Old->getLocation(), PrevDiag); 650 return true; 651 } 652 653 if (getLangOptions().CPlusPlus) { 654 // (C++98 13.1p2): 655 // Certain function declarations cannot be overloaded: 656 // -- Function declarations that differ only in the return type 657 // cannot be overloaded. 658 QualType OldReturnType 659 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 660 QualType NewReturnType 661 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 662 if (OldReturnType != NewReturnType) { 663 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 664 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 665 return true; 666 } 667 668 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 669 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 670 if (OldMethod && NewMethod && 671 OldMethod->getLexicalDeclContext() == 672 NewMethod->getLexicalDeclContext()) { 673 // -- Member function declarations with the same name and the 674 // same parameter types cannot be overloaded if any of them 675 // is a static member function declaration. 676 if (OldMethod->isStatic() || NewMethod->isStatic()) { 677 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 678 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 679 return true; 680 } 681 682 // C++ [class.mem]p1: 683 // [...] A member shall not be declared twice in the 684 // member-specification, except that a nested class or member 685 // class template can be declared and then later defined. 686 unsigned NewDiag; 687 if (isa<CXXConstructorDecl>(OldMethod)) 688 NewDiag = diag::err_constructor_redeclared; 689 else if (isa<CXXDestructorDecl>(NewMethod)) 690 NewDiag = diag::err_destructor_redeclared; 691 else if (isa<CXXConversionDecl>(NewMethod)) 692 NewDiag = diag::err_conv_function_redeclared; 693 else 694 NewDiag = diag::err_member_redeclared; 695 696 Diag(New->getLocation(), NewDiag); 697 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 698 } 699 700 // (C++98 8.3.5p3): 701 // All declarations for a function shall agree exactly in both the 702 // return type and the parameter-type-list. 703 if (OldQType == NewQType) 704 return MergeCompatibleFunctionDecls(New, Old); 705 706 // Fall through for conflicting redeclarations and redefinitions. 707 } 708 709 // C: Function types need to be compatible, not identical. This handles 710 // duplicate function decls like "void f(int); void f(enum X);" properly. 711 if (!getLangOptions().CPlusPlus && 712 Context.typesAreCompatible(OldQType, NewQType)) { 713 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 714 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 715 const FunctionProtoType *OldProto = 0; 716 if (isa<FunctionNoProtoType>(NewFuncType) && 717 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 718 // The old declaration provided a function prototype, but the 719 // new declaration does not. Merge in the prototype. 720 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 721 OldProto->arg_type_end()); 722 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 723 &ParamTypes[0], ParamTypes.size(), 724 OldProto->isVariadic(), 725 OldProto->getTypeQuals()); 726 New->setType(NewQType); 727 New->setInheritedPrototype(); 728 729 // Synthesize a parameter for each argument type. 730 llvm::SmallVector<ParmVarDecl*, 16> Params; 731 for (FunctionProtoType::arg_type_iterator 732 ParamType = OldProto->arg_type_begin(), 733 ParamEnd = OldProto->arg_type_end(); 734 ParamType != ParamEnd; ++ParamType) { 735 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 736 SourceLocation(), 0, 737 *ParamType, VarDecl::None, 738 0); 739 Param->setImplicit(); 740 Params.push_back(Param); 741 } 742 743 New->setParams(Context, &Params[0], Params.size()); 744 } 745 746 return MergeCompatibleFunctionDecls(New, Old); 747 } 748 749 // GNU C permits a K&R definition to follow a prototype declaration 750 // if the declared types of the parameters in the K&R definition 751 // match the types in the prototype declaration, even when the 752 // promoted types of the parameters from the K&R definition differ 753 // from the types in the prototype. GCC then keeps the types from 754 // the prototype. 755 if (!getLangOptions().CPlusPlus && 756 !getLangOptions().NoExtensions && 757 Old->hasPrototype() && !New->hasPrototype() && 758 New->getType()->getAsFunctionProtoType() && 759 Old->getNumParams() == New->getNumParams()) { 760 llvm::SmallVector<QualType, 16> ArgTypes; 761 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 762 const FunctionProtoType *OldProto 763 = Old->getType()->getAsFunctionProtoType(); 764 const FunctionProtoType *NewProto 765 = New->getType()->getAsFunctionProtoType(); 766 767 // Determine whether this is the GNU C extension. 768 bool GNUCompatible = 769 Context.typesAreCompatible(OldProto->getResultType(), 770 NewProto->getResultType()) && 771 (OldProto->isVariadic() == NewProto->isVariadic()); 772 for (unsigned Idx = 0, End = Old->getNumParams(); 773 GNUCompatible && Idx != End; ++Idx) { 774 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 775 ParmVarDecl *NewParm = New->getParamDecl(Idx); 776 if (Context.typesAreCompatible(OldParm->getType(), 777 NewProto->getArgType(Idx))) { 778 ArgTypes.push_back(NewParm->getType()); 779 } else if (Context.typesAreCompatible(OldParm->getType(), 780 NewParm->getType())) { 781 GNUCompatibleParamWarning Warn 782 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 783 Warnings.push_back(Warn); 784 ArgTypes.push_back(NewParm->getType()); 785 } else 786 GNUCompatible = false; 787 } 788 789 if (GNUCompatible) { 790 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 791 Diag(Warnings[Warn].NewParm->getLocation(), 792 diag::ext_param_promoted_not_compatible_with_prototype) 793 << Warnings[Warn].PromotedType 794 << Warnings[Warn].OldParm->getType(); 795 Diag(Warnings[Warn].OldParm->getLocation(), 796 diag::note_previous_declaration); 797 } 798 799 New->setType(Context.getFunctionType(NewProto->getResultType(), 800 &ArgTypes[0], ArgTypes.size(), 801 NewProto->isVariadic(), 802 NewProto->getTypeQuals())); 803 return MergeCompatibleFunctionDecls(New, Old); 804 } 805 806 // Fall through to diagnose conflicting types. 807 } 808 809 // A function that has already been declared has been redeclared or defined 810 // with a different type- show appropriate diagnostic 811 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 812 // The user has declared a builtin function with an incompatible 813 // signature. 814 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 815 // The function the user is redeclaring is a library-defined 816 // function like 'malloc' or 'printf'. Warn about the 817 // redeclaration, then pretend that we don't know about this 818 // library built-in. 819 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 820 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 821 << Old << Old->getType(); 822 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 823 Old->setInvalidDecl(); 824 return false; 825 } 826 827 PrevDiag = diag::note_previous_builtin_declaration; 828 } 829 830 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 831 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 832 return true; 833} 834 835/// \brief Completes the merge of two function declarations that are 836/// known to be compatible. 837/// 838/// This routine handles the merging of attributes and other 839/// properties of function declarations form the old declaration to 840/// the new declaration, once we know that New is in fact a 841/// redeclaration of Old. 842/// 843/// \returns false 844bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 845 // Merge the attributes 846 MergeAttributes(New, Old, Context); 847 848 // Merge the storage class. 849 New->setStorageClass(Old->getStorageClass()); 850 851 // Merge "inline" 852 if (Old->isInline()) 853 New->setInline(true); 854 855 // If this function declaration by itself qualifies as a C99 inline 856 // definition (C99 6.7.4p6), but the previous definition did not, 857 // then the function is not a C99 inline definition. 858 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 859 New->setC99InlineDefinition(false); 860 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 861 // Mark all preceding definitions as not being C99 inline definitions. 862 for (const FunctionDecl *Prev = Old; Prev; 863 Prev = Prev->getPreviousDeclaration()) 864 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 865 } 866 867 // Merge "pure" flag. 868 if (Old->isPure()) 869 New->setPure(); 870 871 // Merge the "deleted" flag. 872 if (Old->isDeleted()) 873 New->setDeleted(); 874 875 if (getLangOptions().CPlusPlus) 876 return MergeCXXFunctionDecl(New, Old); 877 878 return false; 879} 880 881/// MergeVarDecl - We just parsed a variable 'New' which has the same name 882/// and scope as a previous declaration 'Old'. Figure out how to resolve this 883/// situation, merging decls or emitting diagnostics as appropriate. 884/// 885/// Tentative definition rules (C99 6.9.2p2) are checked by 886/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 887/// definitions here, since the initializer hasn't been attached. 888/// 889void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 890 // If either decl is invalid, make sure the new one is marked invalid and 891 // don't do any other checking. 892 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 893 return New->setInvalidDecl(); 894 895 // Verify the old decl was also a variable. 896 VarDecl *Old = dyn_cast<VarDecl>(OldD); 897 if (!Old) { 898 Diag(New->getLocation(), diag::err_redefinition_different_kind) 899 << New->getDeclName(); 900 Diag(OldD->getLocation(), diag::note_previous_definition); 901 return New->setInvalidDecl(); 902 } 903 904 MergeAttributes(New, Old, Context); 905 906 // Merge the types 907 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 908 if (MergedT.isNull()) { 909 Diag(New->getLocation(), diag::err_redefinition_different_type) 910 << New->getDeclName(); 911 Diag(Old->getLocation(), diag::note_previous_definition); 912 return New->setInvalidDecl(); 913 } 914 New->setType(MergedT); 915 916 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 917 if (New->getStorageClass() == VarDecl::Static && 918 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 919 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 920 Diag(Old->getLocation(), diag::note_previous_definition); 921 return New->setInvalidDecl(); 922 } 923 // C99 6.2.2p4: 924 // For an identifier declared with the storage-class specifier 925 // extern in a scope in which a prior declaration of that 926 // identifier is visible,23) if the prior declaration specifies 927 // internal or external linkage, the linkage of the identifier at 928 // the later declaration is the same as the linkage specified at 929 // the prior declaration. If no prior declaration is visible, or 930 // if the prior declaration specifies no linkage, then the 931 // identifier has external linkage. 932 if (New->hasExternalStorage() && Old->hasLinkage()) 933 /* Okay */; 934 else if (New->getStorageClass() != VarDecl::Static && 935 Old->getStorageClass() == VarDecl::Static) { 936 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 937 Diag(Old->getLocation(), diag::note_previous_definition); 938 return New->setInvalidDecl(); 939 } 940 941 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 942 943 // FIXME: The test for external storage here seems wrong? We still 944 // need to check for mismatches. 945 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 946 // Don't complain about out-of-line definitions of static members. 947 !(Old->getLexicalDeclContext()->isRecord() && 948 !New->getLexicalDeclContext()->isRecord())) { 949 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 950 Diag(Old->getLocation(), diag::note_previous_definition); 951 return New->setInvalidDecl(); 952 } 953 954 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 955 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 956 Diag(Old->getLocation(), diag::note_previous_definition); 957 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 958 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 959 Diag(Old->getLocation(), diag::note_previous_definition); 960 } 961 962 // Keep a chain of previous declarations. 963 New->setPreviousDeclaration(Old); 964} 965 966/// CheckParmsForFunctionDef - Check that the parameters of the given 967/// function are appropriate for the definition of a function. This 968/// takes care of any checks that cannot be performed on the 969/// declaration itself, e.g., that the types of each of the function 970/// parameters are complete. 971bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 972 bool HasInvalidParm = false; 973 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 974 ParmVarDecl *Param = FD->getParamDecl(p); 975 976 // C99 6.7.5.3p4: the parameters in a parameter type list in a 977 // function declarator that is part of a function definition of 978 // that function shall not have incomplete type. 979 // 980 // This is also C++ [dcl.fct]p6. 981 if (!Param->isInvalidDecl() && 982 RequireCompleteType(Param->getLocation(), Param->getType(), 983 diag::err_typecheck_decl_incomplete_type)) { 984 Param->setInvalidDecl(); 985 HasInvalidParm = true; 986 } 987 988 // C99 6.9.1p5: If the declarator includes a parameter type list, the 989 // declaration of each parameter shall include an identifier. 990 if (Param->getIdentifier() == 0 && 991 !Param->isImplicit() && 992 !getLangOptions().CPlusPlus) 993 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 994 } 995 996 return HasInvalidParm; 997} 998 999/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1000/// no declarator (e.g. "struct foo;") is parsed. 1001Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1002 // FIXME: Error on auto/register at file scope 1003 // FIXME: Error on inline/virtual/explicit 1004 // FIXME: Error on invalid restrict 1005 // FIXME: Warn on useless __thread 1006 // FIXME: Warn on useless const/volatile 1007 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1008 // FIXME: Warn on useless attributes 1009 1010 TagDecl *Tag = 0; 1011 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1012 DS.getTypeSpecType() == DeclSpec::TST_struct || 1013 DS.getTypeSpecType() == DeclSpec::TST_union || 1014 DS.getTypeSpecType() == DeclSpec::TST_enum) 1015 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1016 1017 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1018 if (!Record->getDeclName() && Record->isDefinition() && 1019 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1020 if (getLangOptions().CPlusPlus || 1021 Record->getDeclContext()->isRecord()) 1022 return BuildAnonymousStructOrUnion(S, DS, Record); 1023 1024 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1025 << DS.getSourceRange(); 1026 } 1027 1028 // Microsoft allows unnamed struct/union fields. Don't complain 1029 // about them. 1030 // FIXME: Should we support Microsoft's extensions in this area? 1031 if (Record->getDeclName() && getLangOptions().Microsoft) 1032 return DeclPtrTy::make(Tag); 1033 } 1034 1035 if (!DS.isMissingDeclaratorOk() && 1036 DS.getTypeSpecType() != DeclSpec::TST_error) { 1037 // Warn about typedefs of enums without names, since this is an 1038 // extension in both Microsoft an GNU. 1039 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1040 Tag && isa<EnumDecl>(Tag)) { 1041 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1042 << DS.getSourceRange(); 1043 return DeclPtrTy::make(Tag); 1044 } 1045 1046 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1047 << DS.getSourceRange(); 1048 return DeclPtrTy(); 1049 } 1050 1051 return DeclPtrTy::make(Tag); 1052} 1053 1054/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1055/// anonymous struct or union AnonRecord into the owning context Owner 1056/// and scope S. This routine will be invoked just after we realize 1057/// that an unnamed union or struct is actually an anonymous union or 1058/// struct, e.g., 1059/// 1060/// @code 1061/// union { 1062/// int i; 1063/// float f; 1064/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1065/// // f into the surrounding scope.x 1066/// @endcode 1067/// 1068/// This routine is recursive, injecting the names of nested anonymous 1069/// structs/unions into the owning context and scope as well. 1070bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1071 RecordDecl *AnonRecord) { 1072 bool Invalid = false; 1073 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1074 FEnd = AnonRecord->field_end(Context); 1075 F != FEnd; ++F) { 1076 if ((*F)->getDeclName()) { 1077 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1078 LookupOrdinaryName, true); 1079 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1080 // C++ [class.union]p2: 1081 // The names of the members of an anonymous union shall be 1082 // distinct from the names of any other entity in the 1083 // scope in which the anonymous union is declared. 1084 unsigned diagKind 1085 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1086 : diag::err_anonymous_struct_member_redecl; 1087 Diag((*F)->getLocation(), diagKind) 1088 << (*F)->getDeclName(); 1089 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1090 Invalid = true; 1091 } else { 1092 // C++ [class.union]p2: 1093 // For the purpose of name lookup, after the anonymous union 1094 // definition, the members of the anonymous union are 1095 // considered to have been defined in the scope in which the 1096 // anonymous union is declared. 1097 Owner->makeDeclVisibleInContext(Context, *F); 1098 S->AddDecl(DeclPtrTy::make(*F)); 1099 IdResolver.AddDecl(*F); 1100 } 1101 } else if (const RecordType *InnerRecordType 1102 = (*F)->getType()->getAsRecordType()) { 1103 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1104 if (InnerRecord->isAnonymousStructOrUnion()) 1105 Invalid = Invalid || 1106 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1107 } 1108 } 1109 1110 return Invalid; 1111} 1112 1113/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1114/// anonymous structure or union. Anonymous unions are a C++ feature 1115/// (C++ [class.union]) and a GNU C extension; anonymous structures 1116/// are a GNU C and GNU C++ extension. 1117Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1118 RecordDecl *Record) { 1119 DeclContext *Owner = Record->getDeclContext(); 1120 1121 // Diagnose whether this anonymous struct/union is an extension. 1122 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1123 Diag(Record->getLocation(), diag::ext_anonymous_union); 1124 else if (!Record->isUnion()) 1125 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1126 1127 // C and C++ require different kinds of checks for anonymous 1128 // structs/unions. 1129 bool Invalid = false; 1130 if (getLangOptions().CPlusPlus) { 1131 const char* PrevSpec = 0; 1132 // C++ [class.union]p3: 1133 // Anonymous unions declared in a named namespace or in the 1134 // global namespace shall be declared static. 1135 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1136 (isa<TranslationUnitDecl>(Owner) || 1137 (isa<NamespaceDecl>(Owner) && 1138 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1139 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1140 Invalid = true; 1141 1142 // Recover by adding 'static'. 1143 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1144 } 1145 // C++ [class.union]p3: 1146 // A storage class is not allowed in a declaration of an 1147 // anonymous union in a class scope. 1148 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1149 isa<RecordDecl>(Owner)) { 1150 Diag(DS.getStorageClassSpecLoc(), 1151 diag::err_anonymous_union_with_storage_spec); 1152 Invalid = true; 1153 1154 // Recover by removing the storage specifier. 1155 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1156 PrevSpec); 1157 } 1158 1159 // C++ [class.union]p2: 1160 // The member-specification of an anonymous union shall only 1161 // define non-static data members. [Note: nested types and 1162 // functions cannot be declared within an anonymous union. ] 1163 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1164 MemEnd = Record->decls_end(Context); 1165 Mem != MemEnd; ++Mem) { 1166 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1167 // C++ [class.union]p3: 1168 // An anonymous union shall not have private or protected 1169 // members (clause 11). 1170 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1171 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1172 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1173 Invalid = true; 1174 } 1175 } else if ((*Mem)->isImplicit()) { 1176 // Any implicit members are fine. 1177 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1178 // This is a type that showed up in an 1179 // elaborated-type-specifier inside the anonymous struct or 1180 // union, but which actually declares a type outside of the 1181 // anonymous struct or union. It's okay. 1182 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1183 if (!MemRecord->isAnonymousStructOrUnion() && 1184 MemRecord->getDeclName()) { 1185 // This is a nested type declaration. 1186 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1187 << (int)Record->isUnion(); 1188 Invalid = true; 1189 } 1190 } else { 1191 // We have something that isn't a non-static data 1192 // member. Complain about it. 1193 unsigned DK = diag::err_anonymous_record_bad_member; 1194 if (isa<TypeDecl>(*Mem)) 1195 DK = diag::err_anonymous_record_with_type; 1196 else if (isa<FunctionDecl>(*Mem)) 1197 DK = diag::err_anonymous_record_with_function; 1198 else if (isa<VarDecl>(*Mem)) 1199 DK = diag::err_anonymous_record_with_static; 1200 Diag((*Mem)->getLocation(), DK) 1201 << (int)Record->isUnion(); 1202 Invalid = true; 1203 } 1204 } 1205 } 1206 1207 if (!Record->isUnion() && !Owner->isRecord()) { 1208 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1209 << (int)getLangOptions().CPlusPlus; 1210 Invalid = true; 1211 } 1212 1213 // Create a declaration for this anonymous struct/union. 1214 NamedDecl *Anon = 0; 1215 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1216 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1217 /*IdentifierInfo=*/0, 1218 Context.getTypeDeclType(Record), 1219 /*BitWidth=*/0, /*Mutable=*/false); 1220 Anon->setAccess(AS_public); 1221 if (getLangOptions().CPlusPlus) 1222 FieldCollector->Add(cast<FieldDecl>(Anon)); 1223 } else { 1224 VarDecl::StorageClass SC; 1225 switch (DS.getStorageClassSpec()) { 1226 default: assert(0 && "Unknown storage class!"); 1227 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1228 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1229 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1230 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1231 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1232 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1233 case DeclSpec::SCS_mutable: 1234 // mutable can only appear on non-static class members, so it's always 1235 // an error here 1236 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1237 Invalid = true; 1238 SC = VarDecl::None; 1239 break; 1240 } 1241 1242 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1243 /*IdentifierInfo=*/0, 1244 Context.getTypeDeclType(Record), 1245 SC, DS.getSourceRange().getBegin()); 1246 } 1247 Anon->setImplicit(); 1248 1249 // Add the anonymous struct/union object to the current 1250 // context. We'll be referencing this object when we refer to one of 1251 // its members. 1252 Owner->addDecl(Context, Anon); 1253 1254 // Inject the members of the anonymous struct/union into the owning 1255 // context and into the identifier resolver chain for name lookup 1256 // purposes. 1257 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1258 Invalid = true; 1259 1260 // Mark this as an anonymous struct/union type. Note that we do not 1261 // do this until after we have already checked and injected the 1262 // members of this anonymous struct/union type, because otherwise 1263 // the members could be injected twice: once by DeclContext when it 1264 // builds its lookup table, and once by 1265 // InjectAnonymousStructOrUnionMembers. 1266 Record->setAnonymousStructOrUnion(true); 1267 1268 if (Invalid) 1269 Anon->setInvalidDecl(); 1270 1271 return DeclPtrTy::make(Anon); 1272} 1273 1274 1275/// GetNameForDeclarator - Determine the full declaration name for the 1276/// given Declarator. 1277DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1278 switch (D.getKind()) { 1279 case Declarator::DK_Abstract: 1280 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1281 return DeclarationName(); 1282 1283 case Declarator::DK_Normal: 1284 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1285 return DeclarationName(D.getIdentifier()); 1286 1287 case Declarator::DK_Constructor: { 1288 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1289 Ty = Context.getCanonicalType(Ty); 1290 return Context.DeclarationNames.getCXXConstructorName(Ty); 1291 } 1292 1293 case Declarator::DK_Destructor: { 1294 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1295 Ty = Context.getCanonicalType(Ty); 1296 return Context.DeclarationNames.getCXXDestructorName(Ty); 1297 } 1298 1299 case Declarator::DK_Conversion: { 1300 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1301 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1302 Ty = Context.getCanonicalType(Ty); 1303 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1304 } 1305 1306 case Declarator::DK_Operator: 1307 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1308 return Context.DeclarationNames.getCXXOperatorName( 1309 D.getOverloadedOperator()); 1310 } 1311 1312 assert(false && "Unknown name kind"); 1313 return DeclarationName(); 1314} 1315 1316/// isNearlyMatchingFunction - Determine whether the C++ functions 1317/// Declaration and Definition are "nearly" matching. This heuristic 1318/// is used to improve diagnostics in the case where an out-of-line 1319/// function definition doesn't match any declaration within 1320/// the class or namespace. 1321static bool isNearlyMatchingFunction(ASTContext &Context, 1322 FunctionDecl *Declaration, 1323 FunctionDecl *Definition) { 1324 if (Declaration->param_size() != Definition->param_size()) 1325 return false; 1326 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1327 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1328 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1329 1330 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1331 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1332 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1333 return false; 1334 } 1335 1336 return true; 1337} 1338 1339Sema::DeclPtrTy 1340Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1341 DeclarationName Name = GetNameForDeclarator(D); 1342 1343 // All of these full declarators require an identifier. If it doesn't have 1344 // one, the ParsedFreeStandingDeclSpec action should be used. 1345 if (!Name) { 1346 if (!D.isInvalidType()) // Reject this if we think it is valid. 1347 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1348 diag::err_declarator_need_ident) 1349 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1350 return DeclPtrTy(); 1351 } 1352 1353 // The scope passed in may not be a decl scope. Zip up the scope tree until 1354 // we find one that is. 1355 while ((S->getFlags() & Scope::DeclScope) == 0 || 1356 (S->getFlags() & Scope::TemplateParamScope) != 0) 1357 S = S->getParent(); 1358 1359 DeclContext *DC; 1360 NamedDecl *PrevDecl; 1361 NamedDecl *New; 1362 1363 QualType R = GetTypeForDeclarator(D, S); 1364 if (R.isNull()) { 1365 D.setInvalidType(); 1366 R = Context.IntTy; 1367 if (IsFunctionDefinition) // int(...) 1368 R = Context.getFunctionType(R, 0, 0, true, 0); 1369 1370 } 1371 1372 // See if this is a redefinition of a variable in the same scope. 1373 if (D.getCXXScopeSpec().isInvalid()) { 1374 DC = CurContext; 1375 PrevDecl = 0; 1376 D.setInvalidType(); 1377 } else if (!D.getCXXScopeSpec().isSet()) { 1378 LookupNameKind NameKind = LookupOrdinaryName; 1379 1380 // If the declaration we're planning to build will be a function 1381 // or object with linkage, then look for another declaration with 1382 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1383 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1384 /* Do nothing*/; 1385 else if (R->isFunctionType()) { 1386 if (CurContext->isFunctionOrMethod()) 1387 NameKind = LookupRedeclarationWithLinkage; 1388 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1389 NameKind = LookupRedeclarationWithLinkage; 1390 1391 DC = CurContext; 1392 PrevDecl = LookupName(S, Name, NameKind, true, 1393 D.getDeclSpec().getStorageClassSpec() != 1394 DeclSpec::SCS_static, 1395 D.getIdentifierLoc()); 1396 } else { // Something like "int foo::x;" 1397 DC = computeDeclContext(D.getCXXScopeSpec()); 1398 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1399 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1400 1401 // C++ 7.3.1.2p2: 1402 // Members (including explicit specializations of templates) of a named 1403 // namespace can also be defined outside that namespace by explicit 1404 // qualification of the name being defined, provided that the entity being 1405 // defined was already declared in the namespace and the definition appears 1406 // after the point of declaration in a namespace that encloses the 1407 // declarations namespace. 1408 // 1409 // Note that we only check the context at this point. We don't yet 1410 // have enough information to make sure that PrevDecl is actually 1411 // the declaration we want to match. For example, given: 1412 // 1413 // class X { 1414 // void f(); 1415 // void f(float); 1416 // }; 1417 // 1418 // void X::f(int) { } // ill-formed 1419 // 1420 // In this case, PrevDecl will point to the overload set 1421 // containing the two f's declared in X, but neither of them 1422 // matches. 1423 1424 // First check whether we named the global scope. 1425 if (isa<TranslationUnitDecl>(DC)) { 1426 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1427 << Name << D.getCXXScopeSpec().getRange(); 1428 } else if (!CurContext->Encloses(DC)) { 1429 // The qualifying scope doesn't enclose the original declaration. 1430 // Emit diagnostic based on current scope. 1431 SourceLocation L = D.getIdentifierLoc(); 1432 SourceRange R = D.getCXXScopeSpec().getRange(); 1433 if (isa<FunctionDecl>(CurContext)) 1434 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1435 else 1436 Diag(L, diag::err_invalid_declarator_scope) 1437 << Name << cast<NamedDecl>(DC) << R; 1438 D.setInvalidType(); 1439 } 1440 } 1441 1442 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1443 // Maybe we will complain about the shadowed template parameter. 1444 if (!D.isInvalidType()) 1445 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1446 D.setInvalidType(); 1447 1448 // Just pretend that we didn't see the previous declaration. 1449 PrevDecl = 0; 1450 } 1451 1452 // In C++, the previous declaration we find might be a tag type 1453 // (class or enum). In this case, the new declaration will hide the 1454 // tag type. Note that this does does not apply if we're declaring a 1455 // typedef (C++ [dcl.typedef]p4). 1456 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1457 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1458 PrevDecl = 0; 1459 1460 bool Redeclaration = false; 1461 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1462 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1463 } else if (R->isFunctionType()) { 1464 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1465 IsFunctionDefinition, Redeclaration); 1466 } else { 1467 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1468 } 1469 1470 if (New == 0) 1471 return DeclPtrTy(); 1472 1473 // If this has an identifier and is not an invalid redeclaration, 1474 // add it to the scope stack. 1475 if (Name && !(Redeclaration && New->isInvalidDecl())) 1476 PushOnScopeChains(New, S); 1477 1478 return DeclPtrTy::make(New); 1479} 1480 1481/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1482/// types into constant array types in certain situations which would otherwise 1483/// be errors (for GCC compatibility). 1484static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1485 ASTContext &Context, 1486 bool &SizeIsNegative) { 1487 // This method tries to turn a variable array into a constant 1488 // array even when the size isn't an ICE. This is necessary 1489 // for compatibility with code that depends on gcc's buggy 1490 // constant expression folding, like struct {char x[(int)(char*)2];} 1491 SizeIsNegative = false; 1492 1493 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1494 QualType Pointee = PTy->getPointeeType(); 1495 QualType FixedType = 1496 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1497 if (FixedType.isNull()) return FixedType; 1498 FixedType = Context.getPointerType(FixedType); 1499 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1500 return FixedType; 1501 } 1502 1503 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1504 if (!VLATy) 1505 return QualType(); 1506 // FIXME: We should probably handle this case 1507 if (VLATy->getElementType()->isVariablyModifiedType()) 1508 return QualType(); 1509 1510 Expr::EvalResult EvalResult; 1511 if (!VLATy->getSizeExpr() || 1512 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1513 !EvalResult.Val.isInt()) 1514 return QualType(); 1515 1516 llvm::APSInt &Res = EvalResult.Val.getInt(); 1517 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1518 return Context.getConstantArrayType(VLATy->getElementType(), 1519 Res, ArrayType::Normal, 0); 1520 1521 SizeIsNegative = true; 1522 return QualType(); 1523} 1524 1525/// \brief Register the given locally-scoped external C declaration so 1526/// that it can be found later for redeclarations 1527void 1528Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1529 Scope *S) { 1530 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1531 "Decl is not a locally-scoped decl!"); 1532 // Note that we have a locally-scoped external with this name. 1533 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1534 1535 if (!PrevDecl) 1536 return; 1537 1538 // If there was a previous declaration of this variable, it may be 1539 // in our identifier chain. Update the identifier chain with the new 1540 // declaration. 1541 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1542 // The previous declaration was found on the identifer resolver 1543 // chain, so remove it from its scope. 1544 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1545 S = S->getParent(); 1546 1547 if (S) 1548 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1549 } 1550} 1551 1552/// \brief Diagnose function specifiers on a declaration of an identifier that 1553/// does not identify a function. 1554void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1555 // FIXME: We should probably indicate the identifier in question to avoid 1556 // confusion for constructs like "inline int a(), b;" 1557 if (D.getDeclSpec().isInlineSpecified()) 1558 Diag(D.getDeclSpec().getInlineSpecLoc(), 1559 diag::err_inline_non_function); 1560 1561 if (D.getDeclSpec().isVirtualSpecified()) 1562 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1563 diag::err_virtual_non_function); 1564 1565 if (D.getDeclSpec().isExplicitSpecified()) 1566 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1567 diag::err_explicit_non_function); 1568} 1569 1570NamedDecl* 1571Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1572 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1573 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1574 if (D.getCXXScopeSpec().isSet()) { 1575 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1576 << D.getCXXScopeSpec().getRange(); 1577 D.setInvalidType(); 1578 // Pretend we didn't see the scope specifier. 1579 DC = 0; 1580 } 1581 1582 if (getLangOptions().CPlusPlus) { 1583 // Check that there are no default arguments (C++ only). 1584 CheckExtraCXXDefaultArguments(D); 1585 } 1586 1587 DiagnoseFunctionSpecifiers(D); 1588 1589 if (D.getDeclSpec().isThreadSpecified()) 1590 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1591 1592 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1593 if (!NewTD) return 0; 1594 1595 if (D.isInvalidType()) 1596 NewTD->setInvalidDecl(); 1597 1598 // Handle attributes prior to checking for duplicates in MergeVarDecl 1599 ProcessDeclAttributes(NewTD, D); 1600 // Merge the decl with the existing one if appropriate. If the decl is 1601 // in an outer scope, it isn't the same thing. 1602 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1603 Redeclaration = true; 1604 MergeTypeDefDecl(NewTD, PrevDecl); 1605 } 1606 1607 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1608 // then it shall have block scope. 1609 QualType T = NewTD->getUnderlyingType(); 1610 if (T->isVariablyModifiedType()) { 1611 CurFunctionNeedsScopeChecking = true; 1612 1613 if (S->getFnParent() == 0) { 1614 bool SizeIsNegative; 1615 QualType FixedTy = 1616 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1617 if (!FixedTy.isNull()) { 1618 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1619 NewTD->setUnderlyingType(FixedTy); 1620 } else { 1621 if (SizeIsNegative) 1622 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1623 else if (T->isVariableArrayType()) 1624 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1625 else 1626 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1627 NewTD->setInvalidDecl(); 1628 } 1629 } 1630 } 1631 return NewTD; 1632} 1633 1634/// \brief Determines whether the given declaration is an out-of-scope 1635/// previous declaration. 1636/// 1637/// This routine should be invoked when name lookup has found a 1638/// previous declaration (PrevDecl) that is not in the scope where a 1639/// new declaration by the same name is being introduced. If the new 1640/// declaration occurs in a local scope, previous declarations with 1641/// linkage may still be considered previous declarations (C99 1642/// 6.2.2p4-5, C++ [basic.link]p6). 1643/// 1644/// \param PrevDecl the previous declaration found by name 1645/// lookup 1646/// 1647/// \param DC the context in which the new declaration is being 1648/// declared. 1649/// 1650/// \returns true if PrevDecl is an out-of-scope previous declaration 1651/// for a new delcaration with the same name. 1652static bool 1653isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1654 ASTContext &Context) { 1655 if (!PrevDecl) 1656 return 0; 1657 1658 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1659 // case we need to check each of the overloaded functions. 1660 if (!PrevDecl->hasLinkage()) 1661 return false; 1662 1663 if (Context.getLangOptions().CPlusPlus) { 1664 // C++ [basic.link]p6: 1665 // If there is a visible declaration of an entity with linkage 1666 // having the same name and type, ignoring entities declared 1667 // outside the innermost enclosing namespace scope, the block 1668 // scope declaration declares that same entity and receives the 1669 // linkage of the previous declaration. 1670 DeclContext *OuterContext = DC->getLookupContext(); 1671 if (!OuterContext->isFunctionOrMethod()) 1672 // This rule only applies to block-scope declarations. 1673 return false; 1674 else { 1675 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1676 if (PrevOuterContext->isRecord()) 1677 // We found a member function: ignore it. 1678 return false; 1679 else { 1680 // Find the innermost enclosing namespace for the new and 1681 // previous declarations. 1682 while (!OuterContext->isFileContext()) 1683 OuterContext = OuterContext->getParent(); 1684 while (!PrevOuterContext->isFileContext()) 1685 PrevOuterContext = PrevOuterContext->getParent(); 1686 1687 // The previous declaration is in a different namespace, so it 1688 // isn't the same function. 1689 if (OuterContext->getPrimaryContext() != 1690 PrevOuterContext->getPrimaryContext()) 1691 return false; 1692 } 1693 } 1694 } 1695 1696 return true; 1697} 1698 1699NamedDecl* 1700Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1701 QualType R,NamedDecl* PrevDecl, 1702 bool &Redeclaration) { 1703 DeclarationName Name = GetNameForDeclarator(D); 1704 1705 // Check that there are no default arguments (C++ only). 1706 if (getLangOptions().CPlusPlus) 1707 CheckExtraCXXDefaultArguments(D); 1708 1709 VarDecl *NewVD; 1710 VarDecl::StorageClass SC; 1711 switch (D.getDeclSpec().getStorageClassSpec()) { 1712 default: assert(0 && "Unknown storage class!"); 1713 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1714 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1715 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1716 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1717 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1718 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1719 case DeclSpec::SCS_mutable: 1720 // mutable can only appear on non-static class members, so it's always 1721 // an error here 1722 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1723 D.setInvalidType(); 1724 SC = VarDecl::None; 1725 break; 1726 } 1727 1728 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1729 if (!II) { 1730 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1731 << Name.getAsString(); 1732 return 0; 1733 } 1734 1735 DiagnoseFunctionSpecifiers(D); 1736 1737 if (!DC->isRecord() && S->getFnParent() == 0) { 1738 // C99 6.9p2: The storage-class specifiers auto and register shall not 1739 // appear in the declaration specifiers in an external declaration. 1740 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1741 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1742 D.setInvalidType(); 1743 } 1744 } 1745 if (DC->isRecord() && !CurContext->isRecord()) { 1746 // This is an out-of-line definition of a static data member. 1747 if (SC == VarDecl::Static) { 1748 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1749 diag::err_static_out_of_line) 1750 << CodeModificationHint::CreateRemoval( 1751 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1752 } else if (SC == VarDecl::None) 1753 SC = VarDecl::Static; 1754 } 1755 1756 // The variable can not 1757 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1758 II, R, SC, 1759 // FIXME: Move to DeclGroup... 1760 D.getDeclSpec().getSourceRange().getBegin()); 1761 1762 if (D.isInvalidType()) 1763 NewVD->setInvalidDecl(); 1764 1765 if (D.getDeclSpec().isThreadSpecified()) { 1766 if (NewVD->hasLocalStorage()) 1767 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1768 else if (!Context.Target.isTLSSupported()) 1769 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1770 else 1771 NewVD->setThreadSpecified(true); 1772 } 1773 1774 // Set the lexical context. If the declarator has a C++ scope specifier, the 1775 // lexical context will be different from the semantic context. 1776 NewVD->setLexicalDeclContext(CurContext); 1777 1778 // Handle attributes prior to checking for duplicates in MergeVarDecl 1779 ProcessDeclAttributes(NewVD, D); 1780 1781 // Handle GNU asm-label extension (encoded as an attribute). 1782 if (Expr *E = (Expr*) D.getAsmLabel()) { 1783 // The parser guarantees this is a string. 1784 StringLiteral *SE = cast<StringLiteral>(E); 1785 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1786 SE->getByteLength()))); 1787 } 1788 1789 // If name lookup finds a previous declaration that is not in the 1790 // same scope as the new declaration, this may still be an 1791 // acceptable redeclaration. 1792 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1793 !(NewVD->hasLinkage() && 1794 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1795 PrevDecl = 0; 1796 1797 // Merge the decl with the existing one if appropriate. 1798 if (PrevDecl) { 1799 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1800 // The user tried to define a non-static data member 1801 // out-of-line (C++ [dcl.meaning]p1). 1802 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1803 << D.getCXXScopeSpec().getRange(); 1804 PrevDecl = 0; 1805 NewVD->setInvalidDecl(); 1806 } 1807 } else if (D.getCXXScopeSpec().isSet()) { 1808 // No previous declaration in the qualifying scope. 1809 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1810 << Name << D.getCXXScopeSpec().getRange(); 1811 NewVD->setInvalidDecl(); 1812 } 1813 1814 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1815 1816 // If this is a locally-scoped extern C variable, update the map of 1817 // such variables. 1818 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1819 !NewVD->isInvalidDecl()) 1820 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1821 1822 return NewVD; 1823} 1824 1825/// \brief Perform semantic checking on a newly-created variable 1826/// declaration. 1827/// 1828/// This routine performs all of the type-checking required for a 1829/// variable declaration once it has been build. It is used both to 1830/// check variables after they have been parsed and their declarators 1831/// have been translated into a declaration, and to check 1832/// 1833/// Sets NewVD->isInvalidDecl() if an error was encountered. 1834void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1835 bool &Redeclaration) { 1836 // If the decl is already known invalid, don't check it. 1837 if (NewVD->isInvalidDecl()) 1838 return; 1839 1840 QualType T = NewVD->getType(); 1841 1842 if (T->isObjCInterfaceType()) { 1843 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1844 return NewVD->setInvalidDecl(); 1845 } 1846 1847 // The variable can not have an abstract class type. 1848 if (RequireNonAbstractType(NewVD->getLocation(), T, 1849 diag::err_abstract_type_in_decl, 1850 AbstractVariableType)) 1851 return NewVD->setInvalidDecl(); 1852 1853 // Emit an error if an address space was applied to decl with local storage. 1854 // This includes arrays of objects with address space qualifiers, but not 1855 // automatic variables that point to other address spaces. 1856 // ISO/IEC TR 18037 S5.1.2 1857 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1858 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1859 return NewVD->setInvalidDecl(); 1860 } 1861 1862 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1863 && !NewVD->hasAttr<BlocksAttr>()) 1864 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1865 1866 bool isVM = T->isVariablyModifiedType(); 1867 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1868 CurFunctionNeedsScopeChecking = true; 1869 1870 if ((isVM && NewVD->hasLinkage()) || 1871 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1872 bool SizeIsNegative; 1873 QualType FixedTy = 1874 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1875 1876 if (FixedTy.isNull() && T->isVariableArrayType()) { 1877 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1878 // FIXME: This won't give the correct result for 1879 // int a[10][n]; 1880 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1881 1882 if (NewVD->isFileVarDecl()) 1883 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1884 << SizeRange; 1885 else if (NewVD->getStorageClass() == VarDecl::Static) 1886 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1887 << SizeRange; 1888 else 1889 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1890 << SizeRange; 1891 return NewVD->setInvalidDecl(); 1892 } 1893 1894 if (FixedTy.isNull()) { 1895 if (NewVD->isFileVarDecl()) 1896 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1897 else 1898 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1899 return NewVD->setInvalidDecl(); 1900 } 1901 1902 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1903 NewVD->setType(FixedTy); 1904 } 1905 1906 if (!PrevDecl && NewVD->isExternC(Context)) { 1907 // Since we did not find anything by this name and we're declaring 1908 // an extern "C" variable, look for a non-visible extern "C" 1909 // declaration with the same name. 1910 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1911 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1912 if (Pos != LocallyScopedExternalDecls.end()) 1913 PrevDecl = Pos->second; 1914 } 1915 1916 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1917 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1918 << T; 1919 return NewVD->setInvalidDecl(); 1920 } 1921 1922 if (PrevDecl) { 1923 Redeclaration = true; 1924 MergeVarDecl(NewVD, PrevDecl); 1925 } 1926} 1927 1928NamedDecl* 1929Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1930 QualType R, NamedDecl* PrevDecl, 1931 bool IsFunctionDefinition, bool &Redeclaration) { 1932 assert(R.getTypePtr()->isFunctionType()); 1933 1934 DeclarationName Name = GetNameForDeclarator(D); 1935 FunctionDecl::StorageClass SC = FunctionDecl::None; 1936 switch (D.getDeclSpec().getStorageClassSpec()) { 1937 default: assert(0 && "Unknown storage class!"); 1938 case DeclSpec::SCS_auto: 1939 case DeclSpec::SCS_register: 1940 case DeclSpec::SCS_mutable: 1941 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1942 diag::err_typecheck_sclass_func); 1943 D.setInvalidType(); 1944 break; 1945 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1946 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1947 case DeclSpec::SCS_static: { 1948 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1949 // C99 6.7.1p5: 1950 // The declaration of an identifier for a function that has 1951 // block scope shall have no explicit storage-class specifier 1952 // other than extern 1953 // See also (C++ [dcl.stc]p4). 1954 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1955 diag::err_static_block_func); 1956 SC = FunctionDecl::None; 1957 } else 1958 SC = FunctionDecl::Static; 1959 break; 1960 } 1961 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1962 } 1963 1964 if (D.getDeclSpec().isThreadSpecified()) 1965 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1966 1967 bool isInline = D.getDeclSpec().isInlineSpecified(); 1968 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1969 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1970 1971 // Check that the return type is not an abstract class type. 1972 // For record types, this is done by the AbstractClassUsageDiagnoser once 1973 // the class has been completely parsed. 1974 if (!DC->isRecord() && 1975 RequireNonAbstractType(D.getIdentifierLoc(), 1976 R->getAsFunctionType()->getResultType(), 1977 diag::err_abstract_type_in_decl, 1978 AbstractReturnType)) 1979 D.setInvalidType(); 1980 1981 // Do not allow returning a objc interface by-value. 1982 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1983 Diag(D.getIdentifierLoc(), 1984 diag::err_object_cannot_be_passed_returned_by_value) << 0 1985 << R->getAsFunctionType()->getResultType(); 1986 D.setInvalidType(); 1987 } 1988 1989 bool isVirtualOkay = false; 1990 FunctionDecl *NewFD; 1991 if (D.getKind() == Declarator::DK_Constructor) { 1992 // This is a C++ constructor declaration. 1993 assert(DC->isRecord() && 1994 "Constructors can only be declared in a member context"); 1995 1996 R = CheckConstructorDeclarator(D, R, SC); 1997 1998 // Create the new declaration 1999 NewFD = CXXConstructorDecl::Create(Context, 2000 cast<CXXRecordDecl>(DC), 2001 D.getIdentifierLoc(), Name, R, 2002 isExplicit, isInline, 2003 /*isImplicitlyDeclared=*/false); 2004 } else if (D.getKind() == Declarator::DK_Destructor) { 2005 // This is a C++ destructor declaration. 2006 if (DC->isRecord()) { 2007 R = CheckDestructorDeclarator(D, SC); 2008 2009 NewFD = CXXDestructorDecl::Create(Context, 2010 cast<CXXRecordDecl>(DC), 2011 D.getIdentifierLoc(), Name, R, 2012 isInline, 2013 /*isImplicitlyDeclared=*/false); 2014 2015 isVirtualOkay = true; 2016 } else { 2017 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2018 2019 // Create a FunctionDecl to satisfy the function definition parsing 2020 // code path. 2021 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2022 Name, R, SC, isInline, 2023 /*hasPrototype=*/true, 2024 // FIXME: Move to DeclGroup... 2025 D.getDeclSpec().getSourceRange().getBegin()); 2026 D.setInvalidType(); 2027 } 2028 } else if (D.getKind() == Declarator::DK_Conversion) { 2029 if (!DC->isRecord()) { 2030 Diag(D.getIdentifierLoc(), 2031 diag::err_conv_function_not_member); 2032 return 0; 2033 } 2034 2035 CheckConversionDeclarator(D, R, SC); 2036 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2037 D.getIdentifierLoc(), Name, R, 2038 isInline, isExplicit); 2039 2040 isVirtualOkay = true; 2041 } else if (DC->isRecord()) { 2042 // This is a C++ method declaration. 2043 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2044 D.getIdentifierLoc(), Name, R, 2045 (SC == FunctionDecl::Static), isInline); 2046 2047 isVirtualOkay = (SC != FunctionDecl::Static); 2048 } else { 2049 // Determine whether the function was written with a 2050 // prototype. This true when: 2051 // - we're in C++ (where every function has a prototype), 2052 // - there is a prototype in the declarator, or 2053 // - the type R of the function is some kind of typedef or other reference 2054 // to a type name (which eventually refers to a function type). 2055 bool HasPrototype = 2056 getLangOptions().CPlusPlus || 2057 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2058 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2059 2060 NewFD = FunctionDecl::Create(Context, DC, 2061 D.getIdentifierLoc(), 2062 Name, R, SC, isInline, HasPrototype, 2063 // FIXME: Move to DeclGroup... 2064 D.getDeclSpec().getSourceRange().getBegin()); 2065 } 2066 2067 if (D.isInvalidType()) 2068 NewFD->setInvalidDecl(); 2069 2070 // Set the lexical context. If the declarator has a C++ 2071 // scope specifier, the lexical context will be different 2072 // from the semantic context. 2073 NewFD->setLexicalDeclContext(CurContext); 2074 2075 // C++ [dcl.fct.spec]p5: 2076 // The virtual specifier shall only be used in declarations of 2077 // nonstatic class member functions that appear within a 2078 // member-specification of a class declaration; see 10.3. 2079 // 2080 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2081 // function is also virtual if it overrides an already virtual 2082 // function. This is important to do here because it's part of the 2083 // declaration. 2084 if (isVirtual && !NewFD->isInvalidDecl()) { 2085 if (!isVirtualOkay) { 2086 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2087 diag::err_virtual_non_function); 2088 } else if (!CurContext->isRecord()) { 2089 // 'virtual' was specified outside of the class. 2090 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2091 << CodeModificationHint::CreateRemoval( 2092 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2093 } else { 2094 // Okay: Add virtual to the method. 2095 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2096 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2097 CurClass->setAggregate(false); 2098 CurClass->setPOD(false); 2099 CurClass->setPolymorphic(true); 2100 CurClass->setHasTrivialConstructor(false); 2101 } 2102 } 2103 2104 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2105 !CurContext->isRecord()) { 2106 // C++ [class.static]p1: 2107 // A data or function member of a class may be declared static 2108 // in a class definition, in which case it is a static member of 2109 // the class. 2110 2111 // Complain about the 'static' specifier if it's on an out-of-line 2112 // member function definition. 2113 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2114 diag::err_static_out_of_line) 2115 << CodeModificationHint::CreateRemoval( 2116 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2117 } 2118 2119 // Handle GNU asm-label extension (encoded as an attribute). 2120 if (Expr *E = (Expr*) D.getAsmLabel()) { 2121 // The parser guarantees this is a string. 2122 StringLiteral *SE = cast<StringLiteral>(E); 2123 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2124 SE->getByteLength()))); 2125 } 2126 2127 // Copy the parameter declarations from the declarator D to the function 2128 // declaration NewFD, if they are available. First scavenge them into Params. 2129 llvm::SmallVector<ParmVarDecl*, 16> Params; 2130 if (D.getNumTypeObjects() > 0) { 2131 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2132 2133 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2134 // function that takes no arguments, not a function that takes a 2135 // single void argument. 2136 // We let through "const void" here because Sema::GetTypeForDeclarator 2137 // already checks for that case. 2138 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2139 FTI.ArgInfo[0].Param && 2140 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2141 // Empty arg list, don't push any params. 2142 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2143 2144 // In C++, the empty parameter-type-list must be spelled "void"; a 2145 // typedef of void is not permitted. 2146 if (getLangOptions().CPlusPlus && 2147 Param->getType().getUnqualifiedType() != Context.VoidTy) 2148 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2149 // FIXME: Leaks decl? 2150 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2151 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2152 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2153 } 2154 2155 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2156 // When we're declaring a function with a typedef, typeof, etc as in the 2157 // following example, we'll need to synthesize (unnamed) 2158 // parameters for use in the declaration. 2159 // 2160 // @code 2161 // typedef void fn(int); 2162 // fn f; 2163 // @endcode 2164 2165 // Synthesize a parameter for each argument type. 2166 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2167 AE = FT->arg_type_end(); AI != AE; ++AI) { 2168 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2169 SourceLocation(), 0, 2170 *AI, VarDecl::None, 0); 2171 Param->setImplicit(); 2172 Params.push_back(Param); 2173 } 2174 } 2175 2176 // If NewFD is invalid, then the Params list may not have the right number of 2177 // decls for this FunctionDecl. Because we want the AST to be as correct as 2178 // possible, "fix" these problems by removing or adding params as needed. 2179 if (NewFD->isInvalidDecl()) { 2180 unsigned NumNeededParams = NewFD->getNumParams(); 2181 while (NumNeededParams > Params.size()) { 2182 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2183 SourceLocation(), 0, 2184 Context.IntTy, VarDecl::None, 0); 2185 Param->setImplicit(); 2186 Param->setInvalidDecl(); 2187 Params.push_back(Param); 2188 } 2189 2190 while (NumNeededParams < Params.size()) { 2191 Params.pop_back(); 2192 // FIXME: Don't leak the decl. 2193 } 2194 } 2195 2196 // Finally, we know we have the right number of parameters, install them. 2197 NewFD->setParams(Context, &Params[0], Params.size()); 2198 2199 2200 // If name lookup finds a previous declaration that is not in the 2201 // same scope as the new declaration, this may still be an 2202 // acceptable redeclaration. 2203 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2204 !(NewFD->hasLinkage() && 2205 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2206 PrevDecl = 0; 2207 2208 // FIXME: We need to determine whether the GNU inline attribute will 2209 // be applied to this function declaration, since it affects 2210 // declaration merging. This hack will go away when the FIXME below 2211 // is resolved, since we should be putting *all* attributes onto the 2212 // declaration now. 2213 for (const AttributeList *Attr = D.getDeclSpec().getAttributes(); 2214 Attr; Attr = Attr->getNext()) { 2215 if (Attr->getKind() == AttributeList::AT_gnu_inline) { 2216 NewFD->addAttr(::new (Context) GNUInlineAttr()); 2217 break; 2218 } 2219 } 2220 2221 // Perform semantic checking on the function declaration. 2222 bool OverloadableAttrRequired = false; // FIXME: HACK! 2223 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2224 /*FIXME:*/OverloadableAttrRequired); 2225 2226 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2227 // An out-of-line member function declaration must also be a 2228 // definition (C++ [dcl.meaning]p1). 2229 if (!IsFunctionDefinition) { 2230 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2231 << D.getCXXScopeSpec().getRange(); 2232 NewFD->setInvalidDecl(); 2233 } else if (!Redeclaration) { 2234 // The user tried to provide an out-of-line definition for a 2235 // function that is a member of a class or namespace, but there 2236 // was no such member function declared (C++ [class.mfct]p2, 2237 // C++ [namespace.memdef]p2). For example: 2238 // 2239 // class X { 2240 // void f() const; 2241 // }; 2242 // 2243 // void X::f() { } // ill-formed 2244 // 2245 // Complain about this problem, and attempt to suggest close 2246 // matches (e.g., those that differ only in cv-qualifiers and 2247 // whether the parameter types are references). 2248 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2249 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2250 NewFD->setInvalidDecl(); 2251 2252 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2253 true); 2254 assert(!Prev.isAmbiguous() && 2255 "Cannot have an ambiguity in previous-declaration lookup"); 2256 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2257 Func != FuncEnd; ++Func) { 2258 if (isa<FunctionDecl>(*Func) && 2259 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2260 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2261 } 2262 2263 PrevDecl = 0; 2264 } 2265 } 2266 2267 // Handle attributes. We need to have merged decls when handling attributes 2268 // (for example to check for conflicts, etc). 2269 // FIXME: This needs to happen before we merge declarations. Then, 2270 // let attribute merging cope with attribute conflicts. 2271 ProcessDeclAttributes(NewFD, D); 2272 AddKnownFunctionAttributes(NewFD); 2273 2274 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2275 // If a function name is overloadable in C, then every function 2276 // with that name must be marked "overloadable". 2277 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2278 << Redeclaration << NewFD; 2279 if (PrevDecl) 2280 Diag(PrevDecl->getLocation(), 2281 diag::note_attribute_overloadable_prev_overload); 2282 NewFD->addAttr(::new (Context) OverloadableAttr()); 2283 } 2284 2285 // If this is a locally-scoped extern C function, update the 2286 // map of such names. 2287 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2288 && !NewFD->isInvalidDecl()) 2289 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2290 2291 return NewFD; 2292} 2293 2294/// \brief Perform semantic checking of a new function declaration. 2295/// 2296/// Performs semantic analysis of the new function declaration 2297/// NewFD. This routine performs all semantic checking that does not 2298/// require the actual declarator involved in the declaration, and is 2299/// used both for the declaration of functions as they are parsed 2300/// (called via ActOnDeclarator) and for the declaration of functions 2301/// that have been instantiated via C++ template instantiation (called 2302/// via InstantiateDecl). 2303/// 2304/// This sets NewFD->isInvalidDecl() to true if there was an error. 2305void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2306 bool &Redeclaration, 2307 bool &OverloadableAttrRequired) { 2308 // If NewFD is already known erroneous, don't do any of this checking. 2309 if (NewFD->isInvalidDecl()) 2310 return; 2311 2312 // Semantic checking for this function declaration (in isolation). 2313 if (getLangOptions().CPlusPlus) { 2314 // C++-specific checks. 2315 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2316 CheckConstructor(Constructor); 2317 } else if (isa<CXXDestructorDecl>(NewFD)) { 2318 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2319 Record->setUserDeclaredDestructor(true); 2320 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2321 // user-defined destructor. 2322 Record->setPOD(false); 2323 2324 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2325 // declared destructor. 2326 Record->setHasTrivialDestructor(false); 2327 } else if (CXXConversionDecl *Conversion 2328 = dyn_cast<CXXConversionDecl>(NewFD)) 2329 ActOnConversionDeclarator(Conversion); 2330 2331 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2332 if (NewFD->isOverloadedOperator() && 2333 CheckOverloadedOperatorDeclaration(NewFD)) 2334 return NewFD->setInvalidDecl(); 2335 } 2336 2337 // C99 6.7.4p6: 2338 // [... ] For a function with external linkage, the following 2339 // restrictions apply: [...] If all of the file scope declarations 2340 // for a function in a translation unit include the inline 2341 // function specifier without extern, then the definition in that 2342 // translation unit is an inline definition. An inline definition 2343 // does not provide an external definition for the function, and 2344 // does not forbid an external definition in another translation 2345 // unit. 2346 // 2347 // Here we determine whether this function, in isolation, would be a 2348 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2349 // previous declarations. 2350 if (NewFD->isInline() && 2351 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2352 bool GNUInline = NewFD->hasAttr<GNUInlineAttr>() || 2353 (PrevDecl && PrevDecl->hasAttr<GNUInlineAttr>()); 2354 if (GNUInline || (!getLangOptions().CPlusPlus && !getLangOptions().C99)) { 2355 // GNU "extern inline" is the same as "inline" in C99. 2356 if (NewFD->getStorageClass() == FunctionDecl::Extern) 2357 NewFD->setC99InlineDefinition(true); 2358 } else if (getLangOptions().C99 && 2359 NewFD->getStorageClass() == FunctionDecl::None) 2360 NewFD->setC99InlineDefinition(true); 2361 } 2362 2363 // Check for a previous declaration of this name. 2364 if (!PrevDecl && NewFD->isExternC(Context)) { 2365 // Since we did not find anything by this name and we're declaring 2366 // an extern "C" function, look for a non-visible extern "C" 2367 // declaration with the same name. 2368 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2369 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2370 if (Pos != LocallyScopedExternalDecls.end()) 2371 PrevDecl = Pos->second; 2372 } 2373 2374 // Merge or overload the declaration with an existing declaration of 2375 // the same name, if appropriate. 2376 if (PrevDecl) { 2377 // Determine whether NewFD is an overload of PrevDecl or 2378 // a declaration that requires merging. If it's an overload, 2379 // there's no more work to do here; we'll just add the new 2380 // function to the scope. 2381 OverloadedFunctionDecl::function_iterator MatchedDecl; 2382 2383 if (!getLangOptions().CPlusPlus && 2384 AllowOverloadingOfFunction(PrevDecl, Context)) { 2385 OverloadableAttrRequired = true; 2386 2387 // Functions marked "overloadable" must have a prototype (that 2388 // we can't get through declaration merging). 2389 if (!NewFD->getType()->getAsFunctionProtoType()) { 2390 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2391 << NewFD; 2392 Redeclaration = true; 2393 2394 // Turn this into a variadic function with no parameters. 2395 QualType R = Context.getFunctionType( 2396 NewFD->getType()->getAsFunctionType()->getResultType(), 2397 0, 0, true, 0); 2398 NewFD->setType(R); 2399 return NewFD->setInvalidDecl(); 2400 } 2401 } 2402 2403 if (PrevDecl && 2404 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2405 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2406 Redeclaration = true; 2407 Decl *OldDecl = PrevDecl; 2408 2409 // If PrevDecl was an overloaded function, extract the 2410 // FunctionDecl that matched. 2411 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2412 OldDecl = *MatchedDecl; 2413 2414 // NewFD and OldDecl represent declarations that need to be 2415 // merged. 2416 if (MergeFunctionDecl(NewFD, OldDecl)) 2417 return NewFD->setInvalidDecl(); 2418 2419 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2420 } 2421 } 2422 2423 // In C++, check default arguments now that we have merged decls. Unless 2424 // the lexical context is the class, because in this case this is done 2425 // during delayed parsing anyway. 2426 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2427 CheckCXXDefaultArguments(NewFD); 2428} 2429 2430bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2431 // FIXME: Need strict checking. In C89, we need to check for 2432 // any assignment, increment, decrement, function-calls, or 2433 // commas outside of a sizeof. In C99, it's the same list, 2434 // except that the aforementioned are allowed in unevaluated 2435 // expressions. Everything else falls under the 2436 // "may accept other forms of constant expressions" exception. 2437 // (We never end up here for C++, so the constant expression 2438 // rules there don't matter.) 2439 if (Init->isConstantInitializer(Context)) 2440 return false; 2441 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2442 << Init->getSourceRange(); 2443 return true; 2444} 2445 2446void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2447 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2448} 2449 2450/// AddInitializerToDecl - Adds the initializer Init to the 2451/// declaration dcl. If DirectInit is true, this is C++ direct 2452/// initialization rather than copy initialization. 2453void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2454 Decl *RealDecl = dcl.getAs<Decl>(); 2455 // If there is no declaration, there was an error parsing it. Just ignore 2456 // the initializer. 2457 if (RealDecl == 0) 2458 return; 2459 2460 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2461 // With declarators parsed the way they are, the parser cannot 2462 // distinguish between a normal initializer and a pure-specifier. 2463 // Thus this grotesque test. 2464 IntegerLiteral *IL; 2465 Expr *Init = static_cast<Expr *>(init.get()); 2466 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2467 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2468 if (Method->isVirtual()) { 2469 Method->setPure(); 2470 2471 // A class is abstract if at least one function is pure virtual. 2472 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2473 } else if (!Method->isInvalidDecl()) { 2474 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2475 << Method->getDeclName() << Init->getSourceRange(); 2476 Method->setInvalidDecl(); 2477 } 2478 } else { 2479 Diag(Method->getLocation(), diag::err_member_function_initialization) 2480 << Method->getDeclName() << Init->getSourceRange(); 2481 Method->setInvalidDecl(); 2482 } 2483 return; 2484 } 2485 2486 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2487 if (!VDecl) { 2488 if (getLangOptions().CPlusPlus && 2489 RealDecl->getLexicalDeclContext()->isRecord() && 2490 isa<NamedDecl>(RealDecl)) 2491 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2492 << cast<NamedDecl>(RealDecl)->getDeclName(); 2493 else 2494 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2495 RealDecl->setInvalidDecl(); 2496 return; 2497 } 2498 2499 if (!VDecl->getType()->isArrayType() && 2500 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2501 diag::err_typecheck_decl_incomplete_type)) { 2502 RealDecl->setInvalidDecl(); 2503 return; 2504 } 2505 2506 const VarDecl *Def = 0; 2507 if (VDecl->getDefinition(Def)) { 2508 Diag(VDecl->getLocation(), diag::err_redefinition) 2509 << VDecl->getDeclName(); 2510 Diag(Def->getLocation(), diag::note_previous_definition); 2511 VDecl->setInvalidDecl(); 2512 return; 2513 } 2514 2515 // Take ownership of the expression, now that we're sure we have somewhere 2516 // to put it. 2517 Expr *Init = static_cast<Expr *>(init.release()); 2518 assert(Init && "missing initializer"); 2519 2520 // Get the decls type and save a reference for later, since 2521 // CheckInitializerTypes may change it. 2522 QualType DclT = VDecl->getType(), SavT = DclT; 2523 if (VDecl->isBlockVarDecl()) { 2524 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2525 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2526 VDecl->setInvalidDecl(); 2527 } else if (!VDecl->isInvalidDecl()) { 2528 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2529 VDecl->getDeclName(), DirectInit)) 2530 VDecl->setInvalidDecl(); 2531 2532 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2533 // Don't check invalid declarations to avoid emitting useless diagnostics. 2534 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2535 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2536 CheckForConstantInitializer(Init, DclT); 2537 } 2538 } 2539 } else if (VDecl->isStaticDataMember() && 2540 VDecl->getLexicalDeclContext()->isRecord()) { 2541 // This is an in-class initialization for a static data member, e.g., 2542 // 2543 // struct S { 2544 // static const int value = 17; 2545 // }; 2546 2547 // Attach the initializer 2548 VDecl->setInit(Init); 2549 2550 // C++ [class.mem]p4: 2551 // A member-declarator can contain a constant-initializer only 2552 // if it declares a static member (9.4) of const integral or 2553 // const enumeration type, see 9.4.2. 2554 QualType T = VDecl->getType(); 2555 if (!T->isDependentType() && 2556 (!Context.getCanonicalType(T).isConstQualified() || 2557 !T->isIntegralType())) { 2558 Diag(VDecl->getLocation(), diag::err_member_initialization) 2559 << VDecl->getDeclName() << Init->getSourceRange(); 2560 VDecl->setInvalidDecl(); 2561 } else { 2562 // C++ [class.static.data]p4: 2563 // If a static data member is of const integral or const 2564 // enumeration type, its declaration in the class definition 2565 // can specify a constant-initializer which shall be an 2566 // integral constant expression (5.19). 2567 if (!Init->isTypeDependent() && 2568 !Init->getType()->isIntegralType()) { 2569 // We have a non-dependent, non-integral or enumeration type. 2570 Diag(Init->getSourceRange().getBegin(), 2571 diag::err_in_class_initializer_non_integral_type) 2572 << Init->getType() << Init->getSourceRange(); 2573 VDecl->setInvalidDecl(); 2574 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2575 // Check whether the expression is a constant expression. 2576 llvm::APSInt Value; 2577 SourceLocation Loc; 2578 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2579 Diag(Loc, diag::err_in_class_initializer_non_constant) 2580 << Init->getSourceRange(); 2581 VDecl->setInvalidDecl(); 2582 } else if (!VDecl->getType()->isDependentType()) 2583 ImpCastExprToType(Init, VDecl->getType()); 2584 } 2585 } 2586 } else if (VDecl->isFileVarDecl()) { 2587 if (VDecl->getStorageClass() == VarDecl::Extern) 2588 Diag(VDecl->getLocation(), diag::warn_extern_init); 2589 if (!VDecl->isInvalidDecl()) 2590 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2591 VDecl->getDeclName(), DirectInit)) 2592 VDecl->setInvalidDecl(); 2593 2594 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2595 // Don't check invalid declarations to avoid emitting useless diagnostics. 2596 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2597 // C99 6.7.8p4. All file scoped initializers need to be constant. 2598 CheckForConstantInitializer(Init, DclT); 2599 } 2600 } 2601 // If the type changed, it means we had an incomplete type that was 2602 // completed by the initializer. For example: 2603 // int ary[] = { 1, 3, 5 }; 2604 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2605 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2606 VDecl->setType(DclT); 2607 Init->setType(DclT); 2608 } 2609 2610 // Attach the initializer to the decl. 2611 VDecl->setInit(Init); 2612 2613 // If the previous declaration of VDecl was a tentative definition, 2614 // remove it from the set of tentative definitions. 2615 if (VDecl->getPreviousDeclaration() && 2616 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2617 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2618 = TentativeDefinitions.find(VDecl->getDeclName()); 2619 assert(Pos != TentativeDefinitions.end() && 2620 "Unrecorded tentative definition?"); 2621 TentativeDefinitions.erase(Pos); 2622 } 2623 2624 return; 2625} 2626 2627void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2628 Decl *RealDecl = dcl.getAs<Decl>(); 2629 2630 // If there is no declaration, there was an error parsing it. Just ignore it. 2631 if (RealDecl == 0) 2632 return; 2633 2634 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2635 QualType Type = Var->getType(); 2636 2637 // Record tentative definitions. 2638 if (Var->isTentativeDefinition(Context)) 2639 TentativeDefinitions[Var->getDeclName()] = Var; 2640 2641 // C++ [dcl.init.ref]p3: 2642 // The initializer can be omitted for a reference only in a 2643 // parameter declaration (8.3.5), in the declaration of a 2644 // function return type, in the declaration of a class member 2645 // within its class declaration (9.2), and where the extern 2646 // specifier is explicitly used. 2647 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2648 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2649 << Var->getDeclName() 2650 << SourceRange(Var->getLocation(), Var->getLocation()); 2651 Var->setInvalidDecl(); 2652 return; 2653 } 2654 2655 // C++ [dcl.init]p9: 2656 // 2657 // If no initializer is specified for an object, and the object 2658 // is of (possibly cv-qualified) non-POD class type (or array 2659 // thereof), the object shall be default-initialized; if the 2660 // object is of const-qualified type, the underlying class type 2661 // shall have a user-declared default constructor. 2662 if (getLangOptions().CPlusPlus) { 2663 QualType InitType = Type; 2664 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2665 InitType = Array->getElementType(); 2666 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2667 CXXRecordDecl *RD = 2668 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2669 CXXConstructorDecl *Constructor = 0; 2670 if (!RequireCompleteType(Var->getLocation(), InitType, 2671 diag::err_invalid_incomplete_type_use)) 2672 Constructor 2673 = PerformInitializationByConstructor(InitType, 0, 0, 2674 Var->getLocation(), 2675 SourceRange(Var->getLocation(), 2676 Var->getLocation()), 2677 Var->getDeclName(), 2678 IK_Default); 2679 if (!Constructor) 2680 Var->setInvalidDecl(); 2681 else if (!RD->hasTrivialConstructor()) 2682 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2683 } 2684 } 2685 2686#if 0 2687 // FIXME: Temporarily disabled because we are not properly parsing 2688 // linkage specifications on declarations, e.g., 2689 // 2690 // extern "C" const CGPoint CGPointerZero; 2691 // 2692 // C++ [dcl.init]p9: 2693 // 2694 // If no initializer is specified for an object, and the 2695 // object is of (possibly cv-qualified) non-POD class type (or 2696 // array thereof), the object shall be default-initialized; if 2697 // the object is of const-qualified type, the underlying class 2698 // type shall have a user-declared default 2699 // constructor. Otherwise, if no initializer is specified for 2700 // an object, the object and its subobjects, if any, have an 2701 // indeterminate initial value; if the object or any of its 2702 // subobjects are of const-qualified type, the program is 2703 // ill-formed. 2704 // 2705 // This isn't technically an error in C, so we don't diagnose it. 2706 // 2707 // FIXME: Actually perform the POD/user-defined default 2708 // constructor check. 2709 if (getLangOptions().CPlusPlus && 2710 Context.getCanonicalType(Type).isConstQualified() && 2711 !Var->hasExternalStorage()) 2712 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2713 << Var->getName() 2714 << SourceRange(Var->getLocation(), Var->getLocation()); 2715#endif 2716 } 2717} 2718 2719Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2720 unsigned NumDecls) { 2721 llvm::SmallVector<Decl*, 8> Decls; 2722 2723 for (unsigned i = 0; i != NumDecls; ++i) 2724 if (Decl *D = Group[i].getAs<Decl>()) 2725 Decls.push_back(D); 2726 2727 // Perform semantic analysis that depends on having fully processed both 2728 // the declarator and initializer. 2729 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2730 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2731 if (!IDecl) 2732 continue; 2733 QualType T = IDecl->getType(); 2734 2735 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2736 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2737 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2738 if (!IDecl->isInvalidDecl() && 2739 RequireCompleteType(IDecl->getLocation(), T, 2740 diag::err_typecheck_decl_incomplete_type)) 2741 IDecl->setInvalidDecl(); 2742 } 2743 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2744 // object that has file scope without an initializer, and without a 2745 // storage-class specifier or with the storage-class specifier "static", 2746 // constitutes a tentative definition. Note: A tentative definition with 2747 // external linkage is valid (C99 6.2.2p5). 2748 if (IDecl->isTentativeDefinition(Context)) { 2749 QualType CheckType = T; 2750 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2751 2752 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2753 if (ArrayT) { 2754 CheckType = ArrayT->getElementType(); 2755 DiagID = diag::err_illegal_decl_array_incomplete_type; 2756 } 2757 2758 if (IDecl->isInvalidDecl()) { 2759 // Do nothing with invalid declarations 2760 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2761 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2762 // C99 6.9.2p3: If the declaration of an identifier for an object is 2763 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2764 // declared type shall not be an incomplete type. 2765 IDecl->setInvalidDecl(); 2766 } 2767 } 2768 } 2769 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2770 &Decls[0], Decls.size())); 2771} 2772 2773 2774/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2775/// to introduce parameters into function prototype scope. 2776Sema::DeclPtrTy 2777Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2778 const DeclSpec &DS = D.getDeclSpec(); 2779 2780 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2781 VarDecl::StorageClass StorageClass = VarDecl::None; 2782 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2783 StorageClass = VarDecl::Register; 2784 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2785 Diag(DS.getStorageClassSpecLoc(), 2786 diag::err_invalid_storage_class_in_func_decl); 2787 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2788 } 2789 2790 if (D.getDeclSpec().isThreadSpecified()) 2791 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2792 2793 DiagnoseFunctionSpecifiers(D); 2794 2795 // Check that there are no default arguments inside the type of this 2796 // parameter (C++ only). 2797 if (getLangOptions().CPlusPlus) 2798 CheckExtraCXXDefaultArguments(D); 2799 2800 QualType parmDeclType = GetTypeForDeclarator(D, S); 2801 if (parmDeclType.isNull()) { 2802 D.setInvalidType(true); 2803 parmDeclType = Context.IntTy; 2804 } 2805 2806 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2807 // Can this happen for params? We already checked that they don't conflict 2808 // among each other. Here they can only shadow globals, which is ok. 2809 IdentifierInfo *II = D.getIdentifier(); 2810 if (II) { 2811 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2812 if (PrevDecl->isTemplateParameter()) { 2813 // Maybe we will complain about the shadowed template parameter. 2814 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2815 // Just pretend that we didn't see the previous declaration. 2816 PrevDecl = 0; 2817 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2818 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2819 2820 // Recover by removing the name 2821 II = 0; 2822 D.SetIdentifier(0, D.getIdentifierLoc()); 2823 } 2824 } 2825 } 2826 2827 // Parameters can not be abstract class types. 2828 // For record types, this is done by the AbstractClassUsageDiagnoser once 2829 // the class has been completely parsed. 2830 if (!CurContext->isRecord() && 2831 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2832 diag::err_abstract_type_in_decl, 2833 AbstractParamType)) 2834 D.setInvalidType(true); 2835 2836 QualType T = adjustParameterType(parmDeclType); 2837 2838 ParmVarDecl *New; 2839 if (T == parmDeclType) // parameter type did not need adjustment 2840 New = ParmVarDecl::Create(Context, CurContext, 2841 D.getIdentifierLoc(), II, 2842 parmDeclType, StorageClass, 2843 0); 2844 else // keep track of both the adjusted and unadjusted types 2845 New = OriginalParmVarDecl::Create(Context, CurContext, 2846 D.getIdentifierLoc(), II, T, 2847 parmDeclType, StorageClass, 0); 2848 2849 if (D.isInvalidType()) 2850 New->setInvalidDecl(); 2851 2852 // Parameter declarators cannot be interface types. All ObjC objects are 2853 // passed by reference. 2854 if (T->isObjCInterfaceType()) { 2855 Diag(D.getIdentifierLoc(), 2856 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2857 New->setInvalidDecl(); 2858 } 2859 2860 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2861 if (D.getCXXScopeSpec().isSet()) { 2862 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2863 << D.getCXXScopeSpec().getRange(); 2864 New->setInvalidDecl(); 2865 } 2866 2867 // Add the parameter declaration into this scope. 2868 S->AddDecl(DeclPtrTy::make(New)); 2869 if (II) 2870 IdResolver.AddDecl(New); 2871 2872 ProcessDeclAttributes(New, D); 2873 return DeclPtrTy::make(New); 2874} 2875 2876void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2877 SourceLocation LocAfterDecls) { 2878 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2879 "Not a function declarator!"); 2880 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2881 2882 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2883 // for a K&R function. 2884 if (!FTI.hasPrototype) { 2885 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2886 --i; 2887 if (FTI.ArgInfo[i].Param == 0) { 2888 std::string Code = " int "; 2889 Code += FTI.ArgInfo[i].Ident->getName(); 2890 Code += ";\n"; 2891 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2892 << FTI.ArgInfo[i].Ident 2893 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2894 2895 // Implicitly declare the argument as type 'int' for lack of a better 2896 // type. 2897 DeclSpec DS; 2898 const char* PrevSpec; // unused 2899 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2900 PrevSpec); 2901 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2902 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2903 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2904 } 2905 } 2906 } 2907} 2908 2909Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2910 Declarator &D) { 2911 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2912 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2913 "Not a function declarator!"); 2914 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2915 2916 if (FTI.hasPrototype) { 2917 // FIXME: Diagnose arguments without names in C. 2918 } 2919 2920 Scope *ParentScope = FnBodyScope->getParent(); 2921 2922 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2923 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2924} 2925 2926Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2927 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2928 2929 CurFunctionNeedsScopeChecking = false; 2930 2931 // See if this is a redefinition. 2932 const FunctionDecl *Definition; 2933 if (FD->getBody(Context, Definition)) { 2934 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2935 Diag(Definition->getLocation(), diag::note_previous_definition); 2936 } 2937 2938 // Builtin functions cannot be defined. 2939 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2940 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2941 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2942 FD->setInvalidDecl(); 2943 } 2944 } 2945 2946 // The return type of a function definition must be complete 2947 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2948 QualType ResultType = FD->getResultType(); 2949 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2950 RequireCompleteType(FD->getLocation(), ResultType, 2951 diag::err_func_def_incomplete_result)) 2952 FD->setInvalidDecl(); 2953 2954 // GNU warning -Wmissing-prototypes: 2955 // Warn if a global function is defined without a previous 2956 // prototype declaration. This warning is issued even if the 2957 // definition itself provides a prototype. The aim is to detect 2958 // global functions that fail to be declared in header files. 2959 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2960 !FD->isMain()) { 2961 bool MissingPrototype = true; 2962 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2963 Prev; Prev = Prev->getPreviousDeclaration()) { 2964 // Ignore any declarations that occur in function or method 2965 // scope, because they aren't visible from the header. 2966 if (Prev->getDeclContext()->isFunctionOrMethod()) 2967 continue; 2968 2969 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2970 break; 2971 } 2972 2973 if (MissingPrototype) 2974 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2975 } 2976 2977 PushDeclContext(FnBodyScope, FD); 2978 2979 // Check the validity of our function parameters 2980 CheckParmsForFunctionDef(FD); 2981 2982 // Introduce our parameters into the function scope 2983 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2984 ParmVarDecl *Param = FD->getParamDecl(p); 2985 Param->setOwningFunction(FD); 2986 2987 // If this has an identifier, add it to the scope stack. 2988 if (Param->getIdentifier()) 2989 PushOnScopeChains(Param, FnBodyScope); 2990 } 2991 2992 // Checking attributes of current function definition 2993 // dllimport attribute. 2994 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2995 // dllimport attribute cannot be applied to definition. 2996 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2997 Diag(FD->getLocation(), 2998 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2999 << "dllimport"; 3000 FD->setInvalidDecl(); 3001 return DeclPtrTy::make(FD); 3002 } else { 3003 // If a symbol previously declared dllimport is later defined, the 3004 // attribute is ignored in subsequent references, and a warning is 3005 // emitted. 3006 Diag(FD->getLocation(), 3007 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3008 << FD->getNameAsCString() << "dllimport"; 3009 } 3010 } 3011 return DeclPtrTy::make(FD); 3012} 3013 3014 3015Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3016 Decl *dcl = D.getAs<Decl>(); 3017 CompoundStmt *Body =cast<CompoundStmt>(static_cast<Stmt*>(BodyArg.release())); 3018 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3019 FD->setBody(Body); 3020 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3021 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3022 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3023 MD->setBody(Body); 3024 } else { 3025 Body->Destroy(Context); 3026 return DeclPtrTy(); 3027 } 3028 PopDeclContext(); 3029 // Verify and clean out per-function state. 3030 3031 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3032 3033 // Check goto/label use. 3034 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3035 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3036 LabelStmt *L = I->second; 3037 3038 // Verify that we have no forward references left. If so, there was a goto 3039 // or address of a label taken, but no definition of it. Label fwd 3040 // definitions are indicated with a null substmt. 3041 if (L->getSubStmt() != 0) 3042 continue; 3043 3044 // Emit error. 3045 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3046 3047 // At this point, we have gotos that use the bogus label. Stitch it into 3048 // the function body so that they aren't leaked and that the AST is well 3049 // formed. 3050 if (Body == 0) { 3051 // The whole function wasn't parsed correctly, just delete this. 3052 L->Destroy(Context); 3053 continue; 3054 } 3055 3056 // Otherwise, the body is valid: we want to stitch the label decl into the 3057 // function somewhere so that it is properly owned and so that the goto 3058 // has a valid target. Do this by creating a new compound stmt with the 3059 // label in it. 3060 3061 // Give the label a sub-statement. 3062 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3063 3064 std::vector<Stmt*> Elements(Body->body_begin(), Body->body_end()); 3065 Elements.push_back(L); 3066 Body->setStmts(Context, &Elements[0], Elements.size()); 3067 } 3068 FunctionLabelMap.clear(); 3069 3070 if (!Body) return D; 3071 3072 // Verify that that gotos and switch cases don't jump into scopes illegally. 3073 if (CurFunctionNeedsScopeChecking) 3074 DiagnoseInvalidJumps(Body); 3075 3076 return D; 3077} 3078 3079/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3080/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3081NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3082 IdentifierInfo &II, Scope *S) { 3083 // Before we produce a declaration for an implicitly defined 3084 // function, see whether there was a locally-scoped declaration of 3085 // this name as a function or variable. If so, use that 3086 // (non-visible) declaration, and complain about it. 3087 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3088 = LocallyScopedExternalDecls.find(&II); 3089 if (Pos != LocallyScopedExternalDecls.end()) { 3090 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3091 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3092 return Pos->second; 3093 } 3094 3095 // Extension in C99. Legal in C90, but warn about it. 3096 if (getLangOptions().C99) 3097 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3098 else 3099 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3100 3101 // FIXME: handle stuff like: 3102 // void foo() { extern float X(); } 3103 // void bar() { X(); } <-- implicit decl for X in another scope. 3104 3105 // Set a Declarator for the implicit definition: int foo(); 3106 const char *Dummy; 3107 DeclSpec DS; 3108 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3109 Error = Error; // Silence warning. 3110 assert(!Error && "Error setting up implicit decl!"); 3111 Declarator D(DS, Declarator::BlockContext); 3112 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3113 0, 0, 0, Loc, D), 3114 SourceLocation()); 3115 D.SetIdentifier(&II, Loc); 3116 3117 // Insert this function into translation-unit scope. 3118 3119 DeclContext *PrevDC = CurContext; 3120 CurContext = Context.getTranslationUnitDecl(); 3121 3122 FunctionDecl *FD = 3123 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3124 FD->setImplicit(); 3125 3126 CurContext = PrevDC; 3127 3128 AddKnownFunctionAttributes(FD); 3129 3130 return FD; 3131} 3132 3133/// \brief Adds any function attributes that we know a priori based on 3134/// the declaration of this function. 3135/// 3136/// These attributes can apply both to implicitly-declared builtins 3137/// (like __builtin___printf_chk) or to library-declared functions 3138/// like NSLog or printf. 3139void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3140 if (FD->isInvalidDecl()) 3141 return; 3142 3143 // If this is a built-in function, map its builtin attributes to 3144 // actual attributes. 3145 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3146 // Handle printf-formatting attributes. 3147 unsigned FormatIdx; 3148 bool HasVAListArg; 3149 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3150 if (!FD->getAttr<FormatAttr>()) 3151 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3152 FormatIdx + 2)); 3153 } 3154 3155 // Mark const if we don't care about errno and that is the only 3156 // thing preventing the function from being const. This allows 3157 // IRgen to use LLVM intrinsics for such functions. 3158 if (!getLangOptions().MathErrno && 3159 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3160 if (!FD->getAttr<ConstAttr>()) 3161 FD->addAttr(::new (Context) ConstAttr()); 3162 } 3163 } 3164 3165 IdentifierInfo *Name = FD->getIdentifier(); 3166 if (!Name) 3167 return; 3168 if ((!getLangOptions().CPlusPlus && 3169 FD->getDeclContext()->isTranslationUnit()) || 3170 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3171 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3172 LinkageSpecDecl::lang_c)) { 3173 // Okay: this could be a libc/libm/Objective-C function we know 3174 // about. 3175 } else 3176 return; 3177 3178 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3179 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3180 // FIXME: We known better than our headers. 3181 const_cast<FormatAttr *>(Format)->setType("printf"); 3182 } else 3183 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3184 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3185 if (!FD->getAttr<FormatAttr>()) 3186 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3187 } 3188} 3189 3190TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3191 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3192 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3193 3194 // Scope manipulation handled by caller. 3195 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3196 D.getIdentifierLoc(), 3197 D.getIdentifier(), 3198 T); 3199 3200 if (TagType *TT = dyn_cast<TagType>(T)) { 3201 TagDecl *TD = TT->getDecl(); 3202 3203 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3204 // keep track of the TypedefDecl. 3205 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3206 TD->setTypedefForAnonDecl(NewTD); 3207 } 3208 3209 if (D.isInvalidType()) 3210 NewTD->setInvalidDecl(); 3211 return NewTD; 3212} 3213 3214/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3215/// former case, Name will be non-null. In the later case, Name will be null. 3216/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3217/// reference/declaration/definition of a tag. 3218Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3219 SourceLocation KWLoc, const CXXScopeSpec &SS, 3220 IdentifierInfo *Name, SourceLocation NameLoc, 3221 AttributeList *Attr, AccessSpecifier AS) { 3222 // If this is not a definition, it must have a name. 3223 assert((Name != 0 || TK == TK_Definition) && 3224 "Nameless record must be a definition!"); 3225 3226 TagDecl::TagKind Kind; 3227 switch (TagSpec) { 3228 default: assert(0 && "Unknown tag type!"); 3229 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3230 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3231 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3232 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3233 } 3234 3235 DeclContext *SearchDC = CurContext; 3236 DeclContext *DC = CurContext; 3237 NamedDecl *PrevDecl = 0; 3238 3239 bool Invalid = false; 3240 3241 if (Name && SS.isNotEmpty()) { 3242 // We have a nested-name tag ('struct foo::bar'). 3243 3244 // Check for invalid 'foo::'. 3245 if (SS.isInvalid()) { 3246 Name = 0; 3247 goto CreateNewDecl; 3248 } 3249 3250 // FIXME: RequireCompleteDeclContext(SS)? 3251 DC = computeDeclContext(SS); 3252 SearchDC = DC; 3253 // Look-up name inside 'foo::'. 3254 PrevDecl = dyn_cast_or_null<TagDecl>( 3255 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3256 3257 // A tag 'foo::bar' must already exist. 3258 if (PrevDecl == 0) { 3259 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3260 Name = 0; 3261 goto CreateNewDecl; 3262 } 3263 } else if (Name) { 3264 // If this is a named struct, check to see if there was a previous forward 3265 // declaration or definition. 3266 // FIXME: We're looking into outer scopes here, even when we 3267 // shouldn't be. Doing so can result in ambiguities that we 3268 // shouldn't be diagnosing. 3269 LookupResult R = LookupName(S, Name, LookupTagName, 3270 /*RedeclarationOnly=*/(TK != TK_Reference)); 3271 if (R.isAmbiguous()) { 3272 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3273 // FIXME: This is not best way to recover from case like: 3274 // 3275 // struct S s; 3276 // 3277 // causes needless "incomplete type" error later. 3278 Name = 0; 3279 PrevDecl = 0; 3280 Invalid = true; 3281 } 3282 else 3283 PrevDecl = R; 3284 3285 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3286 // FIXME: This makes sure that we ignore the contexts associated 3287 // with C structs, unions, and enums when looking for a matching 3288 // tag declaration or definition. See the similar lookup tweak 3289 // in Sema::LookupName; is there a better way to deal with this? 3290 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3291 SearchDC = SearchDC->getParent(); 3292 } 3293 } 3294 3295 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3296 // Maybe we will complain about the shadowed template parameter. 3297 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3298 // Just pretend that we didn't see the previous declaration. 3299 PrevDecl = 0; 3300 } 3301 3302 if (PrevDecl) { 3303 // Check whether the previous declaration is usable. 3304 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3305 3306 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3307 // If this is a use of a previous tag, or if the tag is already declared 3308 // in the same scope (so that the definition/declaration completes or 3309 // rementions the tag), reuse the decl. 3310 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3311 // Make sure that this wasn't declared as an enum and now used as a 3312 // struct or something similar. 3313 if (PrevTagDecl->getTagKind() != Kind) { 3314 bool SafeToContinue 3315 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3316 Kind != TagDecl::TK_enum); 3317 if (SafeToContinue) 3318 Diag(KWLoc, diag::err_use_with_wrong_tag) 3319 << Name 3320 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3321 PrevTagDecl->getKindName()); 3322 else 3323 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3324 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3325 3326 if (SafeToContinue) 3327 Kind = PrevTagDecl->getTagKind(); 3328 else { 3329 // Recover by making this an anonymous redefinition. 3330 Name = 0; 3331 PrevDecl = 0; 3332 Invalid = true; 3333 } 3334 } 3335 3336 if (!Invalid) { 3337 // If this is a use, just return the declaration we found. 3338 3339 // FIXME: In the future, return a variant or some other clue 3340 // for the consumer of this Decl to know it doesn't own it. 3341 // For our current ASTs this shouldn't be a problem, but will 3342 // need to be changed with DeclGroups. 3343 if (TK == TK_Reference) 3344 return DeclPtrTy::make(PrevDecl); 3345 3346 // Diagnose attempts to redefine a tag. 3347 if (TK == TK_Definition) { 3348 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3349 Diag(NameLoc, diag::err_redefinition) << Name; 3350 Diag(Def->getLocation(), diag::note_previous_definition); 3351 // If this is a redefinition, recover by making this 3352 // struct be anonymous, which will make any later 3353 // references get the previous definition. 3354 Name = 0; 3355 PrevDecl = 0; 3356 Invalid = true; 3357 } else { 3358 // If the type is currently being defined, complain 3359 // about a nested redefinition. 3360 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3361 if (Tag->isBeingDefined()) { 3362 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3363 Diag(PrevTagDecl->getLocation(), 3364 diag::note_previous_definition); 3365 Name = 0; 3366 PrevDecl = 0; 3367 Invalid = true; 3368 } 3369 } 3370 3371 // Okay, this is definition of a previously declared or referenced 3372 // tag PrevDecl. We're going to create a new Decl for it. 3373 } 3374 } 3375 // If we get here we have (another) forward declaration or we 3376 // have a definition. Just create a new decl. 3377 } else { 3378 // If we get here, this is a definition of a new tag type in a nested 3379 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3380 // new decl/type. We set PrevDecl to NULL so that the entities 3381 // have distinct types. 3382 PrevDecl = 0; 3383 } 3384 // If we get here, we're going to create a new Decl. If PrevDecl 3385 // is non-NULL, it's a definition of the tag declared by 3386 // PrevDecl. If it's NULL, we have a new definition. 3387 } else { 3388 // PrevDecl is a namespace, template, or anything else 3389 // that lives in the IDNS_Tag identifier namespace. 3390 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3391 // The tag name clashes with a namespace name, issue an error and 3392 // recover by making this tag be anonymous. 3393 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3394 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3395 Name = 0; 3396 PrevDecl = 0; 3397 Invalid = true; 3398 } else { 3399 // The existing declaration isn't relevant to us; we're in a 3400 // new scope, so clear out the previous declaration. 3401 PrevDecl = 0; 3402 } 3403 } 3404 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3405 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3406 // C.scope.pdecl]p5: 3407 // -- for an elaborated-type-specifier of the form 3408 // 3409 // class-key identifier 3410 // 3411 // if the elaborated-type-specifier is used in the 3412 // decl-specifier-seq or parameter-declaration-clause of a 3413 // function defined in namespace scope, the identifier is 3414 // declared as a class-name in the namespace that contains 3415 // the declaration; otherwise, except as a friend 3416 // declaration, the identifier is declared in the smallest 3417 // non-class, non-function-prototype scope that contains the 3418 // declaration. 3419 // 3420 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3421 // C structs and unions. 3422 // 3423 // GNU C also supports this behavior as part of its incomplete 3424 // enum types extension, while GNU C++ does not. 3425 // 3426 // Find the context where we'll be declaring the tag. 3427 // FIXME: We would like to maintain the current DeclContext as the 3428 // lexical context, 3429 while (SearchDC->isRecord()) 3430 SearchDC = SearchDC->getParent(); 3431 3432 // Find the scope where we'll be declaring the tag. 3433 while (S->isClassScope() || 3434 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3435 ((S->getFlags() & Scope::DeclScope) == 0) || 3436 (S->getEntity() && 3437 ((DeclContext *)S->getEntity())->isTransparentContext())) 3438 S = S->getParent(); 3439 } 3440 3441CreateNewDecl: 3442 3443 // If there is an identifier, use the location of the identifier as the 3444 // location of the decl, otherwise use the location of the struct/union 3445 // keyword. 3446 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3447 3448 // Otherwise, create a new declaration. If there is a previous 3449 // declaration of the same entity, the two will be linked via 3450 // PrevDecl. 3451 TagDecl *New; 3452 3453 if (Kind == TagDecl::TK_enum) { 3454 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3455 // enum X { A, B, C } D; D should chain to X. 3456 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3457 cast_or_null<EnumDecl>(PrevDecl)); 3458 // If this is an undefined enum, warn. 3459 if (TK != TK_Definition && !Invalid) { 3460 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3461 : diag::ext_forward_ref_enum; 3462 Diag(Loc, DK); 3463 } 3464 } else { 3465 // struct/union/class 3466 3467 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3468 // struct X { int A; } D; D should chain to X. 3469 if (getLangOptions().CPlusPlus) 3470 // FIXME: Look for a way to use RecordDecl for simple structs. 3471 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3472 cast_or_null<CXXRecordDecl>(PrevDecl)); 3473 else 3474 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3475 cast_or_null<RecordDecl>(PrevDecl)); 3476 } 3477 3478 if (Kind != TagDecl::TK_enum) { 3479 // Handle #pragma pack: if the #pragma pack stack has non-default 3480 // alignment, make up a packed attribute for this decl. These 3481 // attributes are checked when the ASTContext lays out the 3482 // structure. 3483 // 3484 // It is important for implementing the correct semantics that this 3485 // happen here (in act on tag decl). The #pragma pack stack is 3486 // maintained as a result of parser callbacks which can occur at 3487 // many points during the parsing of a struct declaration (because 3488 // the #pragma tokens are effectively skipped over during the 3489 // parsing of the struct). 3490 if (unsigned Alignment = getPragmaPackAlignment()) 3491 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3492 } 3493 3494 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3495 // C++ [dcl.typedef]p3: 3496 // [...] Similarly, in a given scope, a class or enumeration 3497 // shall not be declared with the same name as a typedef-name 3498 // that is declared in that scope and refers to a type other 3499 // than the class or enumeration itself. 3500 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3501 TypedefDecl *PrevTypedef = 0; 3502 if (Lookup.getKind() == LookupResult::Found) 3503 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3504 3505 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3506 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3507 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3508 Diag(Loc, diag::err_tag_definition_of_typedef) 3509 << Context.getTypeDeclType(New) 3510 << PrevTypedef->getUnderlyingType(); 3511 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3512 Invalid = true; 3513 } 3514 } 3515 3516 if (Invalid) 3517 New->setInvalidDecl(); 3518 3519 if (Attr) 3520 ProcessDeclAttributeList(New, Attr); 3521 3522 // If we're declaring or defining a tag in function prototype scope 3523 // in C, note that this type can only be used within the function. 3524 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3525 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3526 3527 // Set the lexical context. If the tag has a C++ scope specifier, the 3528 // lexical context will be different from the semantic context. 3529 New->setLexicalDeclContext(CurContext); 3530 3531 // Set the access specifier. 3532 SetMemberAccessSpecifier(New, PrevDecl, AS); 3533 3534 if (TK == TK_Definition) 3535 New->startDefinition(); 3536 3537 // If this has an identifier, add it to the scope stack. 3538 if (Name) { 3539 S = getNonFieldDeclScope(S); 3540 PushOnScopeChains(New, S); 3541 } else { 3542 CurContext->addDecl(Context, New); 3543 } 3544 3545 return DeclPtrTy::make(New); 3546} 3547 3548void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3549 AdjustDeclIfTemplate(TagD); 3550 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3551 3552 // Enter the tag context. 3553 PushDeclContext(S, Tag); 3554 3555 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3556 FieldCollector->StartClass(); 3557 3558 if (Record->getIdentifier()) { 3559 // C++ [class]p2: 3560 // [...] The class-name is also inserted into the scope of the 3561 // class itself; this is known as the injected-class-name. For 3562 // purposes of access checking, the injected-class-name is treated 3563 // as if it were a public member name. 3564 CXXRecordDecl *InjectedClassName 3565 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3566 CurContext, Record->getLocation(), 3567 Record->getIdentifier(), Record); 3568 InjectedClassName->setImplicit(); 3569 InjectedClassName->setAccess(AS_public); 3570 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3571 InjectedClassName->setDescribedClassTemplate(Template); 3572 PushOnScopeChains(InjectedClassName, S); 3573 assert(InjectedClassName->isInjectedClassName() && 3574 "Broken injected-class-name"); 3575 } 3576 } 3577} 3578 3579void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3580 AdjustDeclIfTemplate(TagD); 3581 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3582 3583 if (isa<CXXRecordDecl>(Tag)) 3584 FieldCollector->FinishClass(); 3585 3586 // Exit this scope of this tag's definition. 3587 PopDeclContext(); 3588 3589 // Notify the consumer that we've defined a tag. 3590 Consumer.HandleTagDeclDefinition(Tag); 3591} 3592 3593// Note that FieldName may be null for anonymous bitfields. 3594bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3595 QualType FieldTy, const Expr *BitWidth) { 3596 3597 // C99 6.7.2.1p4 - verify the field type. 3598 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3599 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3600 // Handle incomplete types with specific error. 3601 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3602 return true; 3603 if (FieldName) 3604 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3605 << FieldName << FieldTy << BitWidth->getSourceRange(); 3606 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3607 << FieldTy << BitWidth->getSourceRange(); 3608 } 3609 3610 // If the bit-width is type- or value-dependent, don't try to check 3611 // it now. 3612 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3613 return false; 3614 3615 llvm::APSInt Value; 3616 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3617 return true; 3618 3619 // Zero-width bitfield is ok for anonymous field. 3620 if (Value == 0 && FieldName) 3621 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3622 3623 if (Value.isSigned() && Value.isNegative()) { 3624 if (FieldName) 3625 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3626 << FieldName << Value.toString(10); 3627 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3628 << Value.toString(10); 3629 } 3630 3631 if (!FieldTy->isDependentType()) { 3632 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3633 if (Value.getZExtValue() > TypeSize) { 3634 if (FieldName) 3635 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3636 << FieldName << (unsigned)TypeSize; 3637 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3638 << (unsigned)TypeSize; 3639 } 3640 } 3641 3642 return false; 3643} 3644 3645/// ActOnField - Each field of a struct/union/class is passed into this in order 3646/// to create a FieldDecl object for it. 3647Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3648 SourceLocation DeclStart, 3649 Declarator &D, ExprTy *BitfieldWidth) { 3650 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3651 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3652 AS_public); 3653 return DeclPtrTy::make(Res); 3654} 3655 3656/// HandleField - Analyze a field of a C struct or a C++ data member. 3657/// 3658FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3659 SourceLocation DeclStart, 3660 Declarator &D, Expr *BitWidth, 3661 AccessSpecifier AS) { 3662 IdentifierInfo *II = D.getIdentifier(); 3663 SourceLocation Loc = DeclStart; 3664 if (II) Loc = D.getIdentifierLoc(); 3665 3666 QualType T = GetTypeForDeclarator(D, S); 3667 if (getLangOptions().CPlusPlus) 3668 CheckExtraCXXDefaultArguments(D); 3669 3670 DiagnoseFunctionSpecifiers(D); 3671 3672 if (D.getDeclSpec().isThreadSpecified()) 3673 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3674 3675 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3676 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3677 PrevDecl = 0; 3678 3679 FieldDecl *NewFD 3680 = CheckFieldDecl(II, T, Record, Loc, 3681 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3682 BitWidth, AS, PrevDecl, &D); 3683 if (NewFD->isInvalidDecl() && PrevDecl) { 3684 // Don't introduce NewFD into scope; there's already something 3685 // with the same name in the same scope. 3686 } else if (II) { 3687 PushOnScopeChains(NewFD, S); 3688 } else 3689 Record->addDecl(Context, NewFD); 3690 3691 return NewFD; 3692} 3693 3694/// \brief Build a new FieldDecl and check its well-formedness. 3695/// 3696/// This routine builds a new FieldDecl given the fields name, type, 3697/// record, etc. \p PrevDecl should refer to any previous declaration 3698/// with the same name and in the same scope as the field to be 3699/// created. 3700/// 3701/// \returns a new FieldDecl. 3702/// 3703/// \todo The Declarator argument is a hack. It will be removed once 3704FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3705 RecordDecl *Record, SourceLocation Loc, 3706 bool Mutable, Expr *BitWidth, 3707 AccessSpecifier AS, NamedDecl *PrevDecl, 3708 Declarator *D) { 3709 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3710 bool InvalidDecl = false; 3711 if (D) InvalidDecl = D->isInvalidType(); 3712 3713 // If we receive a broken type, recover by assuming 'int' and 3714 // marking this declaration as invalid. 3715 if (T.isNull()) { 3716 InvalidDecl = true; 3717 T = Context.IntTy; 3718 } 3719 3720 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3721 // than a variably modified type. 3722 if (T->isVariablyModifiedType()) { 3723 bool SizeIsNegative; 3724 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3725 SizeIsNegative); 3726 if (!FixedTy.isNull()) { 3727 Diag(Loc, diag::warn_illegal_constant_array_size); 3728 T = FixedTy; 3729 } else { 3730 if (SizeIsNegative) 3731 Diag(Loc, diag::err_typecheck_negative_array_size); 3732 else 3733 Diag(Loc, diag::err_typecheck_field_variable_size); 3734 T = Context.IntTy; 3735 InvalidDecl = true; 3736 } 3737 } 3738 3739 // Fields can not have abstract class types 3740 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3741 AbstractFieldType)) 3742 InvalidDecl = true; 3743 3744 // If this is declared as a bit-field, check the bit-field. 3745 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3746 InvalidDecl = true; 3747 DeleteExpr(BitWidth); 3748 BitWidth = 0; 3749 } 3750 3751 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3752 Mutable); 3753 if (InvalidDecl) 3754 NewFD->setInvalidDecl(); 3755 3756 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3757 Diag(Loc, diag::err_duplicate_member) << II; 3758 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3759 NewFD->setInvalidDecl(); 3760 Record->setInvalidDecl(); 3761 } 3762 3763 if (getLangOptions().CPlusPlus && !T->isPODType()) 3764 cast<CXXRecordDecl>(Record)->setPOD(false); 3765 3766 // FIXME: We need to pass in the attributes given an AST 3767 // representation, not a parser representation. 3768 if (D) 3769 ProcessDeclAttributes(NewFD, *D); 3770 3771 if (T.isObjCGCWeak()) 3772 Diag(Loc, diag::warn_attribute_weak_on_field); 3773 3774 NewFD->setAccess(AS); 3775 3776 // C++ [dcl.init.aggr]p1: 3777 // An aggregate is an array or a class (clause 9) with [...] no 3778 // private or protected non-static data members (clause 11). 3779 // A POD must be an aggregate. 3780 if (getLangOptions().CPlusPlus && 3781 (AS == AS_private || AS == AS_protected)) { 3782 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3783 CXXRecord->setAggregate(false); 3784 CXXRecord->setPOD(false); 3785 } 3786 3787 return NewFD; 3788} 3789 3790/// TranslateIvarVisibility - Translate visibility from a token ID to an 3791/// AST enum value. 3792static ObjCIvarDecl::AccessControl 3793TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3794 switch (ivarVisibility) { 3795 default: assert(0 && "Unknown visitibility kind"); 3796 case tok::objc_private: return ObjCIvarDecl::Private; 3797 case tok::objc_public: return ObjCIvarDecl::Public; 3798 case tok::objc_protected: return ObjCIvarDecl::Protected; 3799 case tok::objc_package: return ObjCIvarDecl::Package; 3800 } 3801} 3802 3803/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3804/// in order to create an IvarDecl object for it. 3805Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3806 SourceLocation DeclStart, 3807 Declarator &D, ExprTy *BitfieldWidth, 3808 tok::ObjCKeywordKind Visibility) { 3809 3810 IdentifierInfo *II = D.getIdentifier(); 3811 Expr *BitWidth = (Expr*)BitfieldWidth; 3812 SourceLocation Loc = DeclStart; 3813 if (II) Loc = D.getIdentifierLoc(); 3814 3815 // FIXME: Unnamed fields can be handled in various different ways, for 3816 // example, unnamed unions inject all members into the struct namespace! 3817 3818 QualType T = GetTypeForDeclarator(D, S); 3819 if (T.isNull()) { 3820 D.setInvalidType(); 3821 T = Context.IntTy; 3822 } 3823 3824 if (BitWidth) { 3825 // 6.7.2.1p3, 6.7.2.1p4 3826 if (VerifyBitField(Loc, II, T, BitWidth)) { 3827 D.setInvalidType(); 3828 DeleteExpr(BitWidth); 3829 BitWidth = 0; 3830 } 3831 } else { 3832 // Not a bitfield. 3833 3834 // validate II. 3835 3836 } 3837 3838 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3839 // than a variably modified type. 3840 if (T->isVariablyModifiedType()) { 3841 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3842 D.setInvalidType(); 3843 } 3844 3845 // Get the visibility (access control) for this ivar. 3846 ObjCIvarDecl::AccessControl ac = 3847 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3848 : ObjCIvarDecl::None; 3849 3850 // Construct the decl. 3851 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3852 (Expr *)BitfieldWidth); 3853 3854 if (II) { 3855 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3856 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3857 && !isa<TagDecl>(PrevDecl)) { 3858 Diag(Loc, diag::err_duplicate_member) << II; 3859 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3860 NewID->setInvalidDecl(); 3861 } 3862 } 3863 3864 // Process attributes attached to the ivar. 3865 ProcessDeclAttributes(NewID, D); 3866 3867 if (D.isInvalidType()) 3868 NewID->setInvalidDecl(); 3869 3870 if (II) { 3871 // FIXME: When interfaces are DeclContexts, we'll need to add 3872 // these to the interface. 3873 S->AddDecl(DeclPtrTy::make(NewID)); 3874 IdResolver.AddDecl(NewID); 3875 } 3876 3877 return DeclPtrTy::make(NewID); 3878} 3879 3880void Sema::ActOnFields(Scope* S, 3881 SourceLocation RecLoc, DeclPtrTy RecDecl, 3882 DeclPtrTy *Fields, unsigned NumFields, 3883 SourceLocation LBrac, SourceLocation RBrac, 3884 AttributeList *Attr) { 3885 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3886 assert(EnclosingDecl && "missing record or interface decl"); 3887 3888 // If the decl this is being inserted into is invalid, then it may be a 3889 // redeclaration or some other bogus case. Don't try to add fields to it. 3890 if (EnclosingDecl->isInvalidDecl()) { 3891 // FIXME: Deallocate fields? 3892 return; 3893 } 3894 3895 3896 // Verify that all the fields are okay. 3897 unsigned NumNamedMembers = 0; 3898 llvm::SmallVector<FieldDecl*, 32> RecFields; 3899 3900 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3901 for (unsigned i = 0; i != NumFields; ++i) { 3902 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3903 3904 // Get the type for the field. 3905 Type *FDTy = FD->getType().getTypePtr(); 3906 3907 if (!FD->isAnonymousStructOrUnion()) { 3908 // Remember all fields written by the user. 3909 RecFields.push_back(FD); 3910 } 3911 3912 // If the field is already invalid for some reason, don't emit more 3913 // diagnostics about it. 3914 if (FD->isInvalidDecl()) 3915 continue; 3916 3917 // C99 6.7.2.1p2: 3918 // A structure or union shall not contain a member with 3919 // incomplete or function type (hence, a structure shall not 3920 // contain an instance of itself, but may contain a pointer to 3921 // an instance of itself), except that the last member of a 3922 // structure with more than one named member may have incomplete 3923 // array type; such a structure (and any union containing, 3924 // possibly recursively, a member that is such a structure) 3925 // shall not be a member of a structure or an element of an 3926 // array. 3927 if (FDTy->isFunctionType()) { 3928 // Field declared as a function. 3929 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3930 << FD->getDeclName(); 3931 FD->setInvalidDecl(); 3932 EnclosingDecl->setInvalidDecl(); 3933 continue; 3934 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3935 Record && Record->isStruct()) { 3936 // Flexible array member. 3937 if (NumNamedMembers < 1) { 3938 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3939 << FD->getDeclName(); 3940 FD->setInvalidDecl(); 3941 EnclosingDecl->setInvalidDecl(); 3942 continue; 3943 } 3944 // Okay, we have a legal flexible array member at the end of the struct. 3945 if (Record) 3946 Record->setHasFlexibleArrayMember(true); 3947 } else if (!FDTy->isDependentType() && 3948 RequireCompleteType(FD->getLocation(), FD->getType(), 3949 diag::err_field_incomplete)) { 3950 // Incomplete type 3951 FD->setInvalidDecl(); 3952 EnclosingDecl->setInvalidDecl(); 3953 continue; 3954 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3955 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3956 // If this is a member of a union, then entire union becomes "flexible". 3957 if (Record && Record->isUnion()) { 3958 Record->setHasFlexibleArrayMember(true); 3959 } else { 3960 // If this is a struct/class and this is not the last element, reject 3961 // it. Note that GCC supports variable sized arrays in the middle of 3962 // structures. 3963 if (i != NumFields-1) 3964 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3965 << FD->getDeclName(); 3966 else { 3967 // We support flexible arrays at the end of structs in 3968 // other structs as an extension. 3969 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3970 << FD->getDeclName(); 3971 if (Record) 3972 Record->setHasFlexibleArrayMember(true); 3973 } 3974 } 3975 } 3976 } else if (FDTy->isObjCInterfaceType()) { 3977 /// A field cannot be an Objective-c object 3978 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3979 FD->setInvalidDecl(); 3980 EnclosingDecl->setInvalidDecl(); 3981 continue; 3982 } 3983 // Keep track of the number of named members. 3984 if (FD->getIdentifier()) 3985 ++NumNamedMembers; 3986 } 3987 3988 // Okay, we successfully defined 'Record'. 3989 if (Record) { 3990 Record->completeDefinition(Context); 3991 } else { 3992 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3993 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3994 ID->setIVarList(ClsFields, RecFields.size(), Context); 3995 ID->setLocEnd(RBrac); 3996 3997 // Must enforce the rule that ivars in the base classes may not be 3998 // duplicates. 3999 if (ID->getSuperClass()) { 4000 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4001 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4002 ObjCIvarDecl* Ivar = (*IVI); 4003 IdentifierInfo *II = Ivar->getIdentifier(); 4004 ObjCIvarDecl* prevIvar = 4005 ID->getSuperClass()->lookupInstanceVariable(Context, II); 4006 if (prevIvar) { 4007 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4008 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4009 } 4010 } 4011 } 4012 } else if (ObjCImplementationDecl *IMPDecl = 4013 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4014 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4015 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) { 4016 // FIXME: Set the DeclContext correctly when we build the 4017 // declarations. 4018 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4019 IMPDecl->addDecl(Context, ClsFields[I]); 4020 } 4021 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4022 } 4023 } 4024 4025 if (Attr) 4026 ProcessDeclAttributeList(Record, Attr); 4027} 4028 4029EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4030 EnumConstantDecl *LastEnumConst, 4031 SourceLocation IdLoc, 4032 IdentifierInfo *Id, 4033 ExprArg val) { 4034 Expr *Val = (Expr *)val.get(); 4035 4036 llvm::APSInt EnumVal(32); 4037 QualType EltTy; 4038 if (Val && !Val->isTypeDependent()) { 4039 // Make sure to promote the operand type to int. 4040 UsualUnaryConversions(Val); 4041 if (Val != val.get()) { 4042 val.release(); 4043 val = Val; 4044 } 4045 4046 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4047 SourceLocation ExpLoc; 4048 if (!Val->isValueDependent() && 4049 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4050 Val = 0; 4051 } else { 4052 EltTy = Val->getType(); 4053 } 4054 } 4055 4056 if (!Val) { 4057 if (LastEnumConst) { 4058 // Assign the last value + 1. 4059 EnumVal = LastEnumConst->getInitVal(); 4060 ++EnumVal; 4061 4062 // Check for overflow on increment. 4063 if (EnumVal < LastEnumConst->getInitVal()) 4064 Diag(IdLoc, diag::warn_enum_value_overflow); 4065 4066 EltTy = LastEnumConst->getType(); 4067 } else { 4068 // First value, set to zero. 4069 EltTy = Context.IntTy; 4070 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4071 } 4072 } 4073 4074 val.release(); 4075 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4076 Val, EnumVal); 4077} 4078 4079 4080Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4081 DeclPtrTy lastEnumConst, 4082 SourceLocation IdLoc, 4083 IdentifierInfo *Id, 4084 SourceLocation EqualLoc, ExprTy *val) { 4085 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4086 EnumConstantDecl *LastEnumConst = 4087 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4088 Expr *Val = static_cast<Expr*>(val); 4089 4090 // The scope passed in may not be a decl scope. Zip up the scope tree until 4091 // we find one that is. 4092 S = getNonFieldDeclScope(S); 4093 4094 // Verify that there isn't already something declared with this name in this 4095 // scope. 4096 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4097 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4098 // Maybe we will complain about the shadowed template parameter. 4099 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4100 // Just pretend that we didn't see the previous declaration. 4101 PrevDecl = 0; 4102 } 4103 4104 if (PrevDecl) { 4105 // When in C++, we may get a TagDecl with the same name; in this case the 4106 // enum constant will 'hide' the tag. 4107 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4108 "Received TagDecl when not in C++!"); 4109 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4110 if (isa<EnumConstantDecl>(PrevDecl)) 4111 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4112 else 4113 Diag(IdLoc, diag::err_redefinition) << Id; 4114 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4115 if (Val) Val->Destroy(Context); 4116 return DeclPtrTy(); 4117 } 4118 } 4119 4120 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4121 IdLoc, Id, Owned(Val)); 4122 4123 // Register this decl in the current scope stack. 4124 if (New) 4125 PushOnScopeChains(New, S); 4126 4127 return DeclPtrTy::make(New); 4128} 4129 4130// FIXME: For consistency with ActOnFields(), we should have the parser 4131// pass in the source location for the left/right braces. 4132void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4133 DeclPtrTy *Elements, unsigned NumElements) { 4134 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4135 QualType EnumType = Context.getTypeDeclType(Enum); 4136 4137 // TODO: If the result value doesn't fit in an int, it must be a long or long 4138 // long value. ISO C does not support this, but GCC does as an extension, 4139 // emit a warning. 4140 unsigned IntWidth = Context.Target.getIntWidth(); 4141 4142 // Verify that all the values are okay, compute the size of the values, and 4143 // reverse the list. 4144 unsigned NumNegativeBits = 0; 4145 unsigned NumPositiveBits = 0; 4146 4147 // Keep track of whether all elements have type int. 4148 bool AllElementsInt = true; 4149 4150 for (unsigned i = 0; i != NumElements; ++i) { 4151 EnumConstantDecl *ECD = 4152 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4153 if (!ECD) continue; // Already issued a diagnostic. 4154 4155 // If the enum value doesn't fit in an int, emit an extension warning. 4156 const llvm::APSInt &InitVal = ECD->getInitVal(); 4157 assert(InitVal.getBitWidth() >= IntWidth && 4158 "Should have promoted value to int"); 4159 if (InitVal.getBitWidth() > IntWidth) { 4160 llvm::APSInt V(InitVal); 4161 V.trunc(IntWidth); 4162 V.extend(InitVal.getBitWidth()); 4163 if (V != InitVal) 4164 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4165 << InitVal.toString(10); 4166 } 4167 4168 // Keep track of the size of positive and negative values. 4169 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4170 NumPositiveBits = std::max(NumPositiveBits, 4171 (unsigned)InitVal.getActiveBits()); 4172 else 4173 NumNegativeBits = std::max(NumNegativeBits, 4174 (unsigned)InitVal.getMinSignedBits()); 4175 4176 // Keep track of whether every enum element has type int (very commmon). 4177 if (AllElementsInt) 4178 AllElementsInt = ECD->getType() == Context.IntTy; 4179 } 4180 4181 // Figure out the type that should be used for this enum. 4182 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4183 QualType BestType; 4184 unsigned BestWidth; 4185 4186 if (NumNegativeBits) { 4187 // If there is a negative value, figure out the smallest integer type (of 4188 // int/long/longlong) that fits. 4189 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4190 BestType = Context.IntTy; 4191 BestWidth = IntWidth; 4192 } else { 4193 BestWidth = Context.Target.getLongWidth(); 4194 4195 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4196 BestType = Context.LongTy; 4197 else { 4198 BestWidth = Context.Target.getLongLongWidth(); 4199 4200 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4201 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4202 BestType = Context.LongLongTy; 4203 } 4204 } 4205 } else { 4206 // If there is no negative value, figure out which of uint, ulong, ulonglong 4207 // fits. 4208 if (NumPositiveBits <= IntWidth) { 4209 BestType = Context.UnsignedIntTy; 4210 BestWidth = IntWidth; 4211 } else if (NumPositiveBits <= 4212 (BestWidth = Context.Target.getLongWidth())) { 4213 BestType = Context.UnsignedLongTy; 4214 } else { 4215 BestWidth = Context.Target.getLongLongWidth(); 4216 assert(NumPositiveBits <= BestWidth && 4217 "How could an initializer get larger than ULL?"); 4218 BestType = Context.UnsignedLongLongTy; 4219 } 4220 } 4221 4222 // Loop over all of the enumerator constants, changing their types to match 4223 // the type of the enum if needed. 4224 for (unsigned i = 0; i != NumElements; ++i) { 4225 EnumConstantDecl *ECD = 4226 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4227 if (!ECD) continue; // Already issued a diagnostic. 4228 4229 // Standard C says the enumerators have int type, but we allow, as an 4230 // extension, the enumerators to be larger than int size. If each 4231 // enumerator value fits in an int, type it as an int, otherwise type it the 4232 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4233 // that X has type 'int', not 'unsigned'. 4234 if (ECD->getType() == Context.IntTy) { 4235 // Make sure the init value is signed. 4236 llvm::APSInt IV = ECD->getInitVal(); 4237 IV.setIsSigned(true); 4238 ECD->setInitVal(IV); 4239 4240 if (getLangOptions().CPlusPlus) 4241 // C++ [dcl.enum]p4: Following the closing brace of an 4242 // enum-specifier, each enumerator has the type of its 4243 // enumeration. 4244 ECD->setType(EnumType); 4245 continue; // Already int type. 4246 } 4247 4248 // Determine whether the value fits into an int. 4249 llvm::APSInt InitVal = ECD->getInitVal(); 4250 bool FitsInInt; 4251 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4252 FitsInInt = InitVal.getActiveBits() < IntWidth; 4253 else 4254 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4255 4256 // If it fits into an integer type, force it. Otherwise force it to match 4257 // the enum decl type. 4258 QualType NewTy; 4259 unsigned NewWidth; 4260 bool NewSign; 4261 if (FitsInInt) { 4262 NewTy = Context.IntTy; 4263 NewWidth = IntWidth; 4264 NewSign = true; 4265 } else if (ECD->getType() == BestType) { 4266 // Already the right type! 4267 if (getLangOptions().CPlusPlus) 4268 // C++ [dcl.enum]p4: Following the closing brace of an 4269 // enum-specifier, each enumerator has the type of its 4270 // enumeration. 4271 ECD->setType(EnumType); 4272 continue; 4273 } else { 4274 NewTy = BestType; 4275 NewWidth = BestWidth; 4276 NewSign = BestType->isSignedIntegerType(); 4277 } 4278 4279 // Adjust the APSInt value. 4280 InitVal.extOrTrunc(NewWidth); 4281 InitVal.setIsSigned(NewSign); 4282 ECD->setInitVal(InitVal); 4283 4284 // Adjust the Expr initializer and type. 4285 if (ECD->getInitExpr()) 4286 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4287 /*isLvalue=*/false)); 4288 if (getLangOptions().CPlusPlus) 4289 // C++ [dcl.enum]p4: Following the closing brace of an 4290 // enum-specifier, each enumerator has the type of its 4291 // enumeration. 4292 ECD->setType(EnumType); 4293 else 4294 ECD->setType(NewTy); 4295 } 4296 4297 Enum->completeDefinition(Context, BestType); 4298} 4299 4300Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4301 ExprArg expr) { 4302 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4303 4304 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4305 Loc, AsmString)); 4306} 4307 4308