SemaDecl.cpp revision bc9ef257b887506228e86a7f4c933aecc8f554a9
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/AST/StmtCXX.h" 22#include "clang/Parse/DeclSpec.h" 23#include "clang/Basic/TargetInfo.h" 24#include "clang/Basic/SourceManager.h" 25// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 26#include "clang/Lex/Preprocessor.h" 27#include "clang/Lex/HeaderSearch.h" 28#include "llvm/ADT/SmallSet.h" 29#include "llvm/ADT/STLExtras.h" 30#include <algorithm> 31#include <functional> 32using namespace clang; 33 34/// getDeclName - Return a pretty name for the specified decl if possible, or 35/// an empty string if not. This is used for pretty crash reporting. 36std::string Sema::getDeclName(DeclPtrTy d) { 37 Decl *D = d.getAs<Decl>(); 38 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 39 return DN->getQualifiedNameAsString(); 40 return ""; 41} 42 43Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 44 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 45} 46 47/// \brief If the identifier refers to a type name within this scope, 48/// return the declaration of that type. 49/// 50/// This routine performs ordinary name lookup of the identifier II 51/// within the given scope, with optional C++ scope specifier SS, to 52/// determine whether the name refers to a type. If so, returns an 53/// opaque pointer (actually a QualType) corresponding to that 54/// type. Otherwise, returns NULL. 55/// 56/// If name lookup results in an ambiguity, this routine will complain 57/// and then return NULL. 58Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 59 Scope *S, const CXXScopeSpec *SS) { 60 // C++ [temp.res]p3: 61 // A qualified-id that refers to a type and in which the 62 // nested-name-specifier depends on a template-parameter (14.6.2) 63 // shall be prefixed by the keyword typename to indicate that the 64 // qualified-id denotes a type, forming an 65 // elaborated-type-specifier (7.1.5.3). 66 // 67 // We therefore do not perform any name lookup up SS is a dependent 68 // scope name. FIXME: we will need to perform a special kind of 69 // lookup if the scope specifier names a member of the current 70 // instantiation. 71 if (SS && isDependentScopeSpecifier(*SS)) 72 return 0; 73 74 NamedDecl *IIDecl = 0; 75 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 76 false, false); 77 switch (Result.getKind()) { 78 case LookupResult::NotFound: 79 case LookupResult::FoundOverloaded: 80 return 0; 81 82 case LookupResult::AmbiguousBaseSubobjectTypes: 83 case LookupResult::AmbiguousBaseSubobjects: 84 case LookupResult::AmbiguousReference: { 85 // Look to see if we have a type anywhere in the list of results. 86 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 87 Res != ResEnd; ++Res) { 88 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 89 if (!IIDecl || 90 (*Res)->getLocation().getRawEncoding() < 91 IIDecl->getLocation().getRawEncoding()) 92 IIDecl = *Res; 93 } 94 } 95 96 if (!IIDecl) { 97 // None of the entities we found is a type, so there is no way 98 // to even assume that the result is a type. In this case, don't 99 // complain about the ambiguity. The parser will either try to 100 // perform this lookup again (e.g., as an object name), which 101 // will produce the ambiguity, or will complain that it expected 102 // a type name. 103 Result.Destroy(); 104 return 0; 105 } 106 107 // We found a type within the ambiguous lookup; diagnose the 108 // ambiguity and then return that type. This might be the right 109 // answer, or it might not be, but it suppresses any attempt to 110 // perform the name lookup again. 111 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 112 break; 113 } 114 115 case LookupResult::Found: 116 IIDecl = Result.getAsDecl(); 117 break; 118 } 119 120 if (IIDecl) { 121 QualType T; 122 123 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 124 // Check whether we can use this type 125 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 126 127 T = Context.getTypeDeclType(TD); 128 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 129 // Check whether we can use this interface. 130 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 131 132 T = Context.getObjCInterfaceType(IDecl); 133 } else 134 return 0; 135 136 if (SS) 137 T = getQualifiedNameType(*SS, T); 138 139 return T.getAsOpaquePtr(); 140 } 141 142 return 0; 143} 144 145/// isTagName() - This method is called *for error recovery purposes only* 146/// to determine if the specified name is a valid tag name ("struct foo"). If 147/// so, this returns the TST for the tag corresponding to it (TST_enum, 148/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 149/// where the user forgot to specify the tag. 150DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 151 // Do a tag name lookup in this scope. 152 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 153 if (R.getKind() == LookupResult::Found) 154 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 155 switch (TD->getTagKind()) { 156 case TagDecl::TK_struct: return DeclSpec::TST_struct; 157 case TagDecl::TK_union: return DeclSpec::TST_union; 158 case TagDecl::TK_class: return DeclSpec::TST_class; 159 case TagDecl::TK_enum: return DeclSpec::TST_enum; 160 } 161 } 162 163 return DeclSpec::TST_unspecified; 164} 165 166 167 168DeclContext *Sema::getContainingDC(DeclContext *DC) { 169 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 170 // A C++ out-of-line method will return to the file declaration context. 171 if (MD->isOutOfLineDefinition()) 172 return MD->getLexicalDeclContext(); 173 174 // A C++ inline method is parsed *after* the topmost class it was declared 175 // in is fully parsed (it's "complete"). 176 // The parsing of a C++ inline method happens at the declaration context of 177 // the topmost (non-nested) class it is lexically declared in. 178 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 179 DC = MD->getParent(); 180 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 181 DC = RD; 182 183 // Return the declaration context of the topmost class the inline method is 184 // declared in. 185 return DC; 186 } 187 188 if (isa<ObjCMethodDecl>(DC)) 189 return Context.getTranslationUnitDecl(); 190 191 return DC->getLexicalParent(); 192} 193 194void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 195 assert(getContainingDC(DC) == CurContext && 196 "The next DeclContext should be lexically contained in the current one."); 197 CurContext = DC; 198 S->setEntity(DC); 199} 200 201void Sema::PopDeclContext() { 202 assert(CurContext && "DeclContext imbalance!"); 203 204 CurContext = getContainingDC(CurContext); 205} 206 207/// \brief Determine whether we allow overloading of the function 208/// PrevDecl with another declaration. 209/// 210/// This routine determines whether overloading is possible, not 211/// whether some new function is actually an overload. It will return 212/// true in C++ (where we can always provide overloads) or, as an 213/// extension, in C when the previous function is already an 214/// overloaded function declaration or has the "overloadable" 215/// attribute. 216static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 217 if (Context.getLangOptions().CPlusPlus) 218 return true; 219 220 if (isa<OverloadedFunctionDecl>(PrevDecl)) 221 return true; 222 223 return PrevDecl->getAttr<OverloadableAttr>() != 0; 224} 225 226/// Add this decl to the scope shadowed decl chains. 227void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 228 // Move up the scope chain until we find the nearest enclosing 229 // non-transparent context. The declaration will be introduced into this 230 // scope. 231 while (S->getEntity() && 232 ((DeclContext *)S->getEntity())->isTransparentContext()) 233 S = S->getParent(); 234 235 S->AddDecl(DeclPtrTy::make(D)); 236 237 // Add scoped declarations into their context, so that they can be 238 // found later. Declarations without a context won't be inserted 239 // into any context. 240 CurContext->addDecl(Context, D); 241 242 // C++ [basic.scope]p4: 243 // -- exactly one declaration shall declare a class name or 244 // enumeration name that is not a typedef name and the other 245 // declarations shall all refer to the same object or 246 // enumerator, or all refer to functions and function templates; 247 // in this case the class name or enumeration name is hidden. 248 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 249 // We are pushing the name of a tag (enum or class). 250 if (CurContext->getLookupContext() 251 == TD->getDeclContext()->getLookupContext()) { 252 // We're pushing the tag into the current context, which might 253 // require some reshuffling in the identifier resolver. 254 IdentifierResolver::iterator 255 I = IdResolver.begin(TD->getDeclName()), 256 IEnd = IdResolver.end(); 257 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 258 NamedDecl *PrevDecl = *I; 259 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 260 PrevDecl = *I, ++I) { 261 if (TD->declarationReplaces(*I)) { 262 // This is a redeclaration. Remove it from the chain and 263 // break out, so that we'll add in the shadowed 264 // declaration. 265 S->RemoveDecl(DeclPtrTy::make(*I)); 266 if (PrevDecl == *I) { 267 IdResolver.RemoveDecl(*I); 268 IdResolver.AddDecl(TD); 269 return; 270 } else { 271 IdResolver.RemoveDecl(*I); 272 break; 273 } 274 } 275 } 276 277 // There is already a declaration with the same name in the same 278 // scope, which is not a tag declaration. It must be found 279 // before we find the new declaration, so insert the new 280 // declaration at the end of the chain. 281 IdResolver.AddShadowedDecl(TD, PrevDecl); 282 283 return; 284 } 285 } 286 } else if (isa<FunctionDecl>(D) && 287 AllowOverloadingOfFunction(D, Context)) { 288 // We are pushing the name of a function, which might be an 289 // overloaded name. 290 FunctionDecl *FD = cast<FunctionDecl>(D); 291 IdentifierResolver::iterator Redecl 292 = std::find_if(IdResolver.begin(FD->getDeclName()), 293 IdResolver.end(), 294 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 295 FD)); 296 if (Redecl != IdResolver.end() && 297 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 298 // There is already a declaration of a function on our 299 // IdResolver chain. Replace it with this declaration. 300 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 301 IdResolver.RemoveDecl(*Redecl); 302 } 303 } else if (isa<ObjCInterfaceDecl>(D)) { 304 // We're pushing an Objective-C interface into the current 305 // context. If there is already an alias declaration, remove it first. 306 for (IdentifierResolver::iterator 307 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 308 I != IEnd; ++I) { 309 if (isa<ObjCCompatibleAliasDecl>(*I)) { 310 S->RemoveDecl(DeclPtrTy::make(*I)); 311 IdResolver.RemoveDecl(*I); 312 break; 313 } 314 } 315 } 316 317 IdResolver.AddDecl(D); 318} 319 320void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 321 if (S->decl_empty()) return; 322 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 323 "Scope shouldn't contain decls!"); 324 325 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 326 I != E; ++I) { 327 Decl *TmpD = (*I).getAs<Decl>(); 328 assert(TmpD && "This decl didn't get pushed??"); 329 330 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 331 NamedDecl *D = cast<NamedDecl>(TmpD); 332 333 if (!D->getDeclName()) continue; 334 335 // Remove this name from our lexical scope. 336 IdResolver.RemoveDecl(D); 337 } 338} 339 340/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 341/// return 0 if one not found. 342ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 343 // The third "scope" argument is 0 since we aren't enabling lazy built-in 344 // creation from this context. 345 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 346 347 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 348} 349 350/// getNonFieldDeclScope - Retrieves the innermost scope, starting 351/// from S, where a non-field would be declared. This routine copes 352/// with the difference between C and C++ scoping rules in structs and 353/// unions. For example, the following code is well-formed in C but 354/// ill-formed in C++: 355/// @code 356/// struct S6 { 357/// enum { BAR } e; 358/// }; 359/// 360/// void test_S6() { 361/// struct S6 a; 362/// a.e = BAR; 363/// } 364/// @endcode 365/// For the declaration of BAR, this routine will return a different 366/// scope. The scope S will be the scope of the unnamed enumeration 367/// within S6. In C++, this routine will return the scope associated 368/// with S6, because the enumeration's scope is a transparent 369/// context but structures can contain non-field names. In C, this 370/// routine will return the translation unit scope, since the 371/// enumeration's scope is a transparent context and structures cannot 372/// contain non-field names. 373Scope *Sema::getNonFieldDeclScope(Scope *S) { 374 while (((S->getFlags() & Scope::DeclScope) == 0) || 375 (S->getEntity() && 376 ((DeclContext *)S->getEntity())->isTransparentContext()) || 377 (S->isClassScope() && !getLangOptions().CPlusPlus)) 378 S = S->getParent(); 379 return S; 380} 381 382void Sema::InitBuiltinVaListType() { 383 if (!Context.getBuiltinVaListType().isNull()) 384 return; 385 386 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 387 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 388 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 389 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 390} 391 392/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 393/// file scope. lazily create a decl for it. ForRedeclaration is true 394/// if we're creating this built-in in anticipation of redeclaring the 395/// built-in. 396NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 397 Scope *S, bool ForRedeclaration, 398 SourceLocation Loc) { 399 Builtin::ID BID = (Builtin::ID)bid; 400 401 if (Context.BuiltinInfo.hasVAListUse(BID)) 402 InitBuiltinVaListType(); 403 404 Builtin::Context::GetBuiltinTypeError Error; 405 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 406 switch (Error) { 407 case Builtin::Context::GE_None: 408 // Okay 409 break; 410 411 case Builtin::Context::GE_Missing_FILE: 412 if (ForRedeclaration) 413 Diag(Loc, diag::err_implicit_decl_requires_stdio) 414 << Context.BuiltinInfo.GetName(BID); 415 return 0; 416 } 417 418 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 419 Diag(Loc, diag::ext_implicit_lib_function_decl) 420 << Context.BuiltinInfo.GetName(BID) 421 << R; 422 if (Context.BuiltinInfo.getHeaderName(BID) && 423 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 424 != Diagnostic::Ignored) 425 Diag(Loc, diag::note_please_include_header) 426 << Context.BuiltinInfo.getHeaderName(BID) 427 << Context.BuiltinInfo.GetName(BID); 428 } 429 430 FunctionDecl *New = FunctionDecl::Create(Context, 431 Context.getTranslationUnitDecl(), 432 Loc, II, R, 433 FunctionDecl::Extern, false, 434 /*hasPrototype=*/true); 435 New->setImplicit(); 436 437 // Create Decl objects for each parameter, adding them to the 438 // FunctionDecl. 439 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 440 llvm::SmallVector<ParmVarDecl*, 16> Params; 441 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 442 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 443 FT->getArgType(i), VarDecl::None, 0)); 444 New->setParams(Context, &Params[0], Params.size()); 445 } 446 447 AddKnownFunctionAttributes(New); 448 449 // TUScope is the translation-unit scope to insert this function into. 450 // FIXME: This is hideous. We need to teach PushOnScopeChains to 451 // relate Scopes to DeclContexts, and probably eliminate CurContext 452 // entirely, but we're not there yet. 453 DeclContext *SavedContext = CurContext; 454 CurContext = Context.getTranslationUnitDecl(); 455 PushOnScopeChains(New, TUScope); 456 CurContext = SavedContext; 457 return New; 458} 459 460/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 461/// everything from the standard library is defined. 462NamespaceDecl *Sema::GetStdNamespace() { 463 if (!StdNamespace) { 464 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 465 DeclContext *Global = Context.getTranslationUnitDecl(); 466 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 467 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 468 } 469 return StdNamespace; 470} 471 472/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 473/// same name and scope as a previous declaration 'Old'. Figure out 474/// how to resolve this situation, merging decls or emitting 475/// diagnostics as appropriate. If there was an error, set New to be invalid. 476/// 477void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 478 // If either decl is known invalid already, set the new one to be invalid and 479 // don't bother doing any merging checks. 480 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 481 return New->setInvalidDecl(); 482 483 bool objc_types = false; 484 485 // Allow multiple definitions for ObjC built-in typedefs. 486 // FIXME: Verify the underlying types are equivalent! 487 if (getLangOptions().ObjC1) { 488 const IdentifierInfo *TypeID = New->getIdentifier(); 489 switch (TypeID->getLength()) { 490 default: break; 491 case 2: 492 if (!TypeID->isStr("id")) 493 break; 494 Context.setObjCIdType(Context.getTypeDeclType(New)); 495 objc_types = true; 496 break; 497 case 5: 498 if (!TypeID->isStr("Class")) 499 break; 500 Context.setObjCClassType(Context.getTypeDeclType(New)); 501 return; 502 case 3: 503 if (!TypeID->isStr("SEL")) 504 break; 505 Context.setObjCSelType(Context.getTypeDeclType(New)); 506 return; 507 case 8: 508 if (!TypeID->isStr("Protocol")) 509 break; 510 Context.setObjCProtoType(New->getUnderlyingType()); 511 return; 512 } 513 // Fall through - the typedef name was not a builtin type. 514 } 515 // Verify the old decl was also a type. 516 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 517 if (!Old) { 518 Diag(New->getLocation(), diag::err_redefinition_different_kind) 519 << New->getDeclName(); 520 if (OldD->getLocation().isValid()) 521 Diag(OldD->getLocation(), diag::note_previous_definition); 522 return New->setInvalidDecl(); 523 } 524 525 // Determine the "old" type we'll use for checking and diagnostics. 526 QualType OldType; 527 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 528 OldType = OldTypedef->getUnderlyingType(); 529 else 530 OldType = Context.getTypeDeclType(Old); 531 532 // If the typedef types are not identical, reject them in all languages and 533 // with any extensions enabled. 534 535 if (OldType != New->getUnderlyingType() && 536 Context.getCanonicalType(OldType) != 537 Context.getCanonicalType(New->getUnderlyingType())) { 538 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 539 << New->getUnderlyingType() << OldType; 540 if (Old->getLocation().isValid()) 541 Diag(Old->getLocation(), diag::note_previous_definition); 542 return New->setInvalidDecl(); 543 } 544 545 if (objc_types || getLangOptions().Microsoft) 546 return; 547 548 // C++ [dcl.typedef]p2: 549 // In a given non-class scope, a typedef specifier can be used to 550 // redefine the name of any type declared in that scope to refer 551 // to the type to which it already refers. 552 if (getLangOptions().CPlusPlus) { 553 if (!isa<CXXRecordDecl>(CurContext)) 554 return; 555 Diag(New->getLocation(), diag::err_redefinition) 556 << New->getDeclName(); 557 Diag(Old->getLocation(), diag::note_previous_definition); 558 return New->setInvalidDecl(); 559 } 560 561 // If we have a redefinition of a typedef in C, emit a warning. This warning 562 // is normally mapped to an error, but can be controlled with 563 // -Wtypedef-redefinition. 564 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 565 << New->getDeclName(); 566 Diag(Old->getLocation(), diag::note_previous_definition); 567 return; 568} 569 570/// DeclhasAttr - returns true if decl Declaration already has the target 571/// attribute. 572static bool DeclHasAttr(const Decl *decl, const Attr *target) { 573 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 574 if (attr->getKind() == target->getKind()) 575 return true; 576 577 return false; 578} 579 580/// MergeAttributes - append attributes from the Old decl to the New one. 581static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 582 Attr *attr = const_cast<Attr*>(Old->getAttrs()); 583 584 while (attr) { 585 Attr *tmp = attr; 586 attr = attr->getNext(); 587 588 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 589 tmp->setInherited(true); 590 New->addAttr(tmp); 591 } else { 592 tmp->setNext(0); 593 tmp->Destroy(C); 594 } 595 } 596 597 Old->invalidateAttrs(); 598} 599 600/// Used in MergeFunctionDecl to keep track of function parameters in 601/// C. 602struct GNUCompatibleParamWarning { 603 ParmVarDecl *OldParm; 604 ParmVarDecl *NewParm; 605 QualType PromotedType; 606}; 607 608/// MergeFunctionDecl - We just parsed a function 'New' from 609/// declarator D which has the same name and scope as a previous 610/// declaration 'Old'. Figure out how to resolve this situation, 611/// merging decls or emitting diagnostics as appropriate. 612/// 613/// In C++, New and Old must be declarations that are not 614/// overloaded. Use IsOverload to determine whether New and Old are 615/// overloaded, and to select the Old declaration that New should be 616/// merged with. 617/// 618/// Returns true if there was an error, false otherwise. 619bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 620 assert(!isa<OverloadedFunctionDecl>(OldD) && 621 "Cannot merge with an overloaded function declaration"); 622 623 // Verify the old decl was also a function. 624 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 625 if (!Old) { 626 Diag(New->getLocation(), diag::err_redefinition_different_kind) 627 << New->getDeclName(); 628 Diag(OldD->getLocation(), diag::note_previous_definition); 629 return true; 630 } 631 632 // Determine whether the previous declaration was a definition, 633 // implicit declaration, or a declaration. 634 diag::kind PrevDiag; 635 if (Old->isThisDeclarationADefinition()) 636 PrevDiag = diag::note_previous_definition; 637 else if (Old->isImplicit()) 638 PrevDiag = diag::note_previous_implicit_declaration; 639 else 640 PrevDiag = diag::note_previous_declaration; 641 642 QualType OldQType = Context.getCanonicalType(Old->getType()); 643 QualType NewQType = Context.getCanonicalType(New->getType()); 644 645 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 646 New->getStorageClass() == FunctionDecl::Static && 647 Old->getStorageClass() != FunctionDecl::Static) { 648 Diag(New->getLocation(), diag::err_static_non_static) 649 << New; 650 Diag(Old->getLocation(), PrevDiag); 651 return true; 652 } 653 654 if (getLangOptions().CPlusPlus) { 655 // (C++98 13.1p2): 656 // Certain function declarations cannot be overloaded: 657 // -- Function declarations that differ only in the return type 658 // cannot be overloaded. 659 QualType OldReturnType 660 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 661 QualType NewReturnType 662 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 663 if (OldReturnType != NewReturnType) { 664 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 665 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 666 return true; 667 } 668 669 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 670 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 671 if (OldMethod && NewMethod && 672 OldMethod->getLexicalDeclContext() == 673 NewMethod->getLexicalDeclContext()) { 674 // -- Member function declarations with the same name and the 675 // same parameter types cannot be overloaded if any of them 676 // is a static member function declaration. 677 if (OldMethod->isStatic() || NewMethod->isStatic()) { 678 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 679 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 680 return true; 681 } 682 683 // C++ [class.mem]p1: 684 // [...] A member shall not be declared twice in the 685 // member-specification, except that a nested class or member 686 // class template can be declared and then later defined. 687 unsigned NewDiag; 688 if (isa<CXXConstructorDecl>(OldMethod)) 689 NewDiag = diag::err_constructor_redeclared; 690 else if (isa<CXXDestructorDecl>(NewMethod)) 691 NewDiag = diag::err_destructor_redeclared; 692 else if (isa<CXXConversionDecl>(NewMethod)) 693 NewDiag = diag::err_conv_function_redeclared; 694 else 695 NewDiag = diag::err_member_redeclared; 696 697 Diag(New->getLocation(), NewDiag); 698 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 699 } 700 701 // (C++98 8.3.5p3): 702 // All declarations for a function shall agree exactly in both the 703 // return type and the parameter-type-list. 704 if (OldQType == NewQType) 705 return MergeCompatibleFunctionDecls(New, Old); 706 707 // Fall through for conflicting redeclarations and redefinitions. 708 } 709 710 // C: Function types need to be compatible, not identical. This handles 711 // duplicate function decls like "void f(int); void f(enum X);" properly. 712 if (!getLangOptions().CPlusPlus && 713 Context.typesAreCompatible(OldQType, NewQType)) { 714 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 715 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 716 const FunctionProtoType *OldProto = 0; 717 if (isa<FunctionNoProtoType>(NewFuncType) && 718 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 719 // The old declaration provided a function prototype, but the 720 // new declaration does not. Merge in the prototype. 721 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 722 OldProto->arg_type_end()); 723 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 724 &ParamTypes[0], ParamTypes.size(), 725 OldProto->isVariadic(), 726 OldProto->getTypeQuals()); 727 New->setType(NewQType); 728 New->setInheritedPrototype(); 729 730 // Synthesize a parameter for each argument type. 731 llvm::SmallVector<ParmVarDecl*, 16> Params; 732 for (FunctionProtoType::arg_type_iterator 733 ParamType = OldProto->arg_type_begin(), 734 ParamEnd = OldProto->arg_type_end(); 735 ParamType != ParamEnd; ++ParamType) { 736 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 737 SourceLocation(), 0, 738 *ParamType, VarDecl::None, 739 0); 740 Param->setImplicit(); 741 Params.push_back(Param); 742 } 743 744 New->setParams(Context, &Params[0], Params.size()); 745 } 746 747 return MergeCompatibleFunctionDecls(New, Old); 748 } 749 750 // GNU C permits a K&R definition to follow a prototype declaration 751 // if the declared types of the parameters in the K&R definition 752 // match the types in the prototype declaration, even when the 753 // promoted types of the parameters from the K&R definition differ 754 // from the types in the prototype. GCC then keeps the types from 755 // the prototype. 756 if (!getLangOptions().CPlusPlus && 757 !getLangOptions().NoExtensions && 758 Old->hasPrototype() && !New->hasPrototype() && 759 New->getType()->getAsFunctionProtoType() && 760 Old->getNumParams() == New->getNumParams()) { 761 llvm::SmallVector<QualType, 16> ArgTypes; 762 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 763 const FunctionProtoType *OldProto 764 = Old->getType()->getAsFunctionProtoType(); 765 const FunctionProtoType *NewProto 766 = New->getType()->getAsFunctionProtoType(); 767 768 // Determine whether this is the GNU C extension. 769 bool GNUCompatible = 770 Context.typesAreCompatible(OldProto->getResultType(), 771 NewProto->getResultType()) && 772 (OldProto->isVariadic() == NewProto->isVariadic()); 773 for (unsigned Idx = 0, End = Old->getNumParams(); 774 GNUCompatible && Idx != End; ++Idx) { 775 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 776 ParmVarDecl *NewParm = New->getParamDecl(Idx); 777 if (Context.typesAreCompatible(OldParm->getType(), 778 NewProto->getArgType(Idx))) { 779 ArgTypes.push_back(NewParm->getType()); 780 } else if (Context.typesAreCompatible(OldParm->getType(), 781 NewParm->getType())) { 782 GNUCompatibleParamWarning Warn 783 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 784 Warnings.push_back(Warn); 785 ArgTypes.push_back(NewParm->getType()); 786 } else 787 GNUCompatible = false; 788 } 789 790 if (GNUCompatible) { 791 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 792 Diag(Warnings[Warn].NewParm->getLocation(), 793 diag::ext_param_promoted_not_compatible_with_prototype) 794 << Warnings[Warn].PromotedType 795 << Warnings[Warn].OldParm->getType(); 796 Diag(Warnings[Warn].OldParm->getLocation(), 797 diag::note_previous_declaration); 798 } 799 800 New->setType(Context.getFunctionType(NewProto->getResultType(), 801 &ArgTypes[0], ArgTypes.size(), 802 NewProto->isVariadic(), 803 NewProto->getTypeQuals())); 804 return MergeCompatibleFunctionDecls(New, Old); 805 } 806 807 // Fall through to diagnose conflicting types. 808 } 809 810 // A function that has already been declared has been redeclared or defined 811 // with a different type- show appropriate diagnostic 812 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 813 // The user has declared a builtin function with an incompatible 814 // signature. 815 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 816 // The function the user is redeclaring is a library-defined 817 // function like 'malloc' or 'printf'. Warn about the 818 // redeclaration, then pretend that we don't know about this 819 // library built-in. 820 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 821 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 822 << Old << Old->getType(); 823 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 824 Old->setInvalidDecl(); 825 return false; 826 } 827 828 PrevDiag = diag::note_previous_builtin_declaration; 829 } 830 831 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 832 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 833 return true; 834} 835 836/// \brief Completes the merge of two function declarations that are 837/// known to be compatible. 838/// 839/// This routine handles the merging of attributes and other 840/// properties of function declarations form the old declaration to 841/// the new declaration, once we know that New is in fact a 842/// redeclaration of Old. 843/// 844/// \returns false 845bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 846 // Merge the attributes 847 MergeAttributes(New, Old, Context); 848 849 // Merge the storage class. 850 New->setStorageClass(Old->getStorageClass()); 851 852 // Merge "inline" 853 if (Old->isInline()) 854 New->setInline(true); 855 856 // If this function declaration by itself qualifies as a C99 inline 857 // definition (C99 6.7.4p6), but the previous definition did not, 858 // then the function is not a C99 inline definition. 859 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 860 New->setC99InlineDefinition(false); 861 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 862 // Mark all preceding definitions as not being C99 inline definitions. 863 for (const FunctionDecl *Prev = Old; Prev; 864 Prev = Prev->getPreviousDeclaration()) 865 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 866 } 867 868 // Merge "pure" flag. 869 if (Old->isPure()) 870 New->setPure(); 871 872 // Merge the "deleted" flag. 873 if (Old->isDeleted()) 874 New->setDeleted(); 875 876 if (getLangOptions().CPlusPlus) 877 return MergeCXXFunctionDecl(New, Old); 878 879 return false; 880} 881 882/// MergeVarDecl - We just parsed a variable 'New' which has the same name 883/// and scope as a previous declaration 'Old'. Figure out how to resolve this 884/// situation, merging decls or emitting diagnostics as appropriate. 885/// 886/// Tentative definition rules (C99 6.9.2p2) are checked by 887/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 888/// definitions here, since the initializer hasn't been attached. 889/// 890void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 891 // If either decl is invalid, make sure the new one is marked invalid and 892 // don't do any other checking. 893 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 894 return New->setInvalidDecl(); 895 896 // Verify the old decl was also a variable. 897 VarDecl *Old = dyn_cast<VarDecl>(OldD); 898 if (!Old) { 899 Diag(New->getLocation(), diag::err_redefinition_different_kind) 900 << New->getDeclName(); 901 Diag(OldD->getLocation(), diag::note_previous_definition); 902 return New->setInvalidDecl(); 903 } 904 905 MergeAttributes(New, Old, Context); 906 907 // Merge the types 908 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 909 if (MergedT.isNull()) { 910 Diag(New->getLocation(), diag::err_redefinition_different_type) 911 << New->getDeclName(); 912 Diag(Old->getLocation(), diag::note_previous_definition); 913 return New->setInvalidDecl(); 914 } 915 New->setType(MergedT); 916 917 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 918 if (New->getStorageClass() == VarDecl::Static && 919 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 920 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 921 Diag(Old->getLocation(), diag::note_previous_definition); 922 return New->setInvalidDecl(); 923 } 924 // C99 6.2.2p4: 925 // For an identifier declared with the storage-class specifier 926 // extern in a scope in which a prior declaration of that 927 // identifier is visible,23) if the prior declaration specifies 928 // internal or external linkage, the linkage of the identifier at 929 // the later declaration is the same as the linkage specified at 930 // the prior declaration. If no prior declaration is visible, or 931 // if the prior declaration specifies no linkage, then the 932 // identifier has external linkage. 933 if (New->hasExternalStorage() && Old->hasLinkage()) 934 /* Okay */; 935 else if (New->getStorageClass() != VarDecl::Static && 936 Old->getStorageClass() == VarDecl::Static) { 937 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 938 Diag(Old->getLocation(), diag::note_previous_definition); 939 return New->setInvalidDecl(); 940 } 941 942 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 943 944 // FIXME: The test for external storage here seems wrong? We still 945 // need to check for mismatches. 946 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 947 // Don't complain about out-of-line definitions of static members. 948 !(Old->getLexicalDeclContext()->isRecord() && 949 !New->getLexicalDeclContext()->isRecord())) { 950 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 951 Diag(Old->getLocation(), diag::note_previous_definition); 952 return New->setInvalidDecl(); 953 } 954 955 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 956 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 957 Diag(Old->getLocation(), diag::note_previous_definition); 958 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 959 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 960 Diag(Old->getLocation(), diag::note_previous_definition); 961 } 962 963 // Keep a chain of previous declarations. 964 New->setPreviousDeclaration(Old); 965} 966 967/// CheckParmsForFunctionDef - Check that the parameters of the given 968/// function are appropriate for the definition of a function. This 969/// takes care of any checks that cannot be performed on the 970/// declaration itself, e.g., that the types of each of the function 971/// parameters are complete. 972bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 973 bool HasInvalidParm = false; 974 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 975 ParmVarDecl *Param = FD->getParamDecl(p); 976 977 // C99 6.7.5.3p4: the parameters in a parameter type list in a 978 // function declarator that is part of a function definition of 979 // that function shall not have incomplete type. 980 // 981 // This is also C++ [dcl.fct]p6. 982 if (!Param->isInvalidDecl() && 983 RequireCompleteType(Param->getLocation(), Param->getType(), 984 diag::err_typecheck_decl_incomplete_type)) { 985 Param->setInvalidDecl(); 986 HasInvalidParm = true; 987 } 988 989 // C99 6.9.1p5: If the declarator includes a parameter type list, the 990 // declaration of each parameter shall include an identifier. 991 if (Param->getIdentifier() == 0 && 992 !Param->isImplicit() && 993 !getLangOptions().CPlusPlus) 994 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 995 } 996 997 return HasInvalidParm; 998} 999 1000/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1001/// no declarator (e.g. "struct foo;") is parsed. 1002Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1003 // FIXME: Error on auto/register at file scope 1004 // FIXME: Error on inline/virtual/explicit 1005 // FIXME: Error on invalid restrict 1006 // FIXME: Warn on useless __thread 1007 // FIXME: Warn on useless const/volatile 1008 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1009 // FIXME: Warn on useless attributes 1010 1011 TagDecl *Tag = 0; 1012 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1013 DS.getTypeSpecType() == DeclSpec::TST_struct || 1014 DS.getTypeSpecType() == DeclSpec::TST_union || 1015 DS.getTypeSpecType() == DeclSpec::TST_enum) 1016 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1017 1018 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1019 if (!Record->getDeclName() && Record->isDefinition() && 1020 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1021 if (getLangOptions().CPlusPlus || 1022 Record->getDeclContext()->isRecord()) 1023 return BuildAnonymousStructOrUnion(S, DS, Record); 1024 1025 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1026 << DS.getSourceRange(); 1027 } 1028 1029 // Microsoft allows unnamed struct/union fields. Don't complain 1030 // about them. 1031 // FIXME: Should we support Microsoft's extensions in this area? 1032 if (Record->getDeclName() && getLangOptions().Microsoft) 1033 return DeclPtrTy::make(Tag); 1034 } 1035 1036 if (!DS.isMissingDeclaratorOk() && 1037 DS.getTypeSpecType() != DeclSpec::TST_error) { 1038 // Warn about typedefs of enums without names, since this is an 1039 // extension in both Microsoft an GNU. 1040 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1041 Tag && isa<EnumDecl>(Tag)) { 1042 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1043 << DS.getSourceRange(); 1044 return DeclPtrTy::make(Tag); 1045 } 1046 1047 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1048 << DS.getSourceRange(); 1049 return DeclPtrTy(); 1050 } 1051 1052 return DeclPtrTy::make(Tag); 1053} 1054 1055/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1056/// anonymous struct or union AnonRecord into the owning context Owner 1057/// and scope S. This routine will be invoked just after we realize 1058/// that an unnamed union or struct is actually an anonymous union or 1059/// struct, e.g., 1060/// 1061/// @code 1062/// union { 1063/// int i; 1064/// float f; 1065/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1066/// // f into the surrounding scope.x 1067/// @endcode 1068/// 1069/// This routine is recursive, injecting the names of nested anonymous 1070/// structs/unions into the owning context and scope as well. 1071bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1072 RecordDecl *AnonRecord) { 1073 bool Invalid = false; 1074 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1075 FEnd = AnonRecord->field_end(Context); 1076 F != FEnd; ++F) { 1077 if ((*F)->getDeclName()) { 1078 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1079 LookupOrdinaryName, true); 1080 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1081 // C++ [class.union]p2: 1082 // The names of the members of an anonymous union shall be 1083 // distinct from the names of any other entity in the 1084 // scope in which the anonymous union is declared. 1085 unsigned diagKind 1086 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1087 : diag::err_anonymous_struct_member_redecl; 1088 Diag((*F)->getLocation(), diagKind) 1089 << (*F)->getDeclName(); 1090 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1091 Invalid = true; 1092 } else { 1093 // C++ [class.union]p2: 1094 // For the purpose of name lookup, after the anonymous union 1095 // definition, the members of the anonymous union are 1096 // considered to have been defined in the scope in which the 1097 // anonymous union is declared. 1098 Owner->makeDeclVisibleInContext(Context, *F); 1099 S->AddDecl(DeclPtrTy::make(*F)); 1100 IdResolver.AddDecl(*F); 1101 } 1102 } else if (const RecordType *InnerRecordType 1103 = (*F)->getType()->getAsRecordType()) { 1104 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1105 if (InnerRecord->isAnonymousStructOrUnion()) 1106 Invalid = Invalid || 1107 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1108 } 1109 } 1110 1111 return Invalid; 1112} 1113 1114/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1115/// anonymous structure or union. Anonymous unions are a C++ feature 1116/// (C++ [class.union]) and a GNU C extension; anonymous structures 1117/// are a GNU C and GNU C++ extension. 1118Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1119 RecordDecl *Record) { 1120 DeclContext *Owner = Record->getDeclContext(); 1121 1122 // Diagnose whether this anonymous struct/union is an extension. 1123 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1124 Diag(Record->getLocation(), diag::ext_anonymous_union); 1125 else if (!Record->isUnion()) 1126 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1127 1128 // C and C++ require different kinds of checks for anonymous 1129 // structs/unions. 1130 bool Invalid = false; 1131 if (getLangOptions().CPlusPlus) { 1132 const char* PrevSpec = 0; 1133 // C++ [class.union]p3: 1134 // Anonymous unions declared in a named namespace or in the 1135 // global namespace shall be declared static. 1136 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1137 (isa<TranslationUnitDecl>(Owner) || 1138 (isa<NamespaceDecl>(Owner) && 1139 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1140 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1141 Invalid = true; 1142 1143 // Recover by adding 'static'. 1144 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1145 } 1146 // C++ [class.union]p3: 1147 // A storage class is not allowed in a declaration of an 1148 // anonymous union in a class scope. 1149 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1150 isa<RecordDecl>(Owner)) { 1151 Diag(DS.getStorageClassSpecLoc(), 1152 diag::err_anonymous_union_with_storage_spec); 1153 Invalid = true; 1154 1155 // Recover by removing the storage specifier. 1156 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1157 PrevSpec); 1158 } 1159 1160 // C++ [class.union]p2: 1161 // The member-specification of an anonymous union shall only 1162 // define non-static data members. [Note: nested types and 1163 // functions cannot be declared within an anonymous union. ] 1164 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1165 MemEnd = Record->decls_end(Context); 1166 Mem != MemEnd; ++Mem) { 1167 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1168 // C++ [class.union]p3: 1169 // An anonymous union shall not have private or protected 1170 // members (clause 11). 1171 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1172 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1173 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1174 Invalid = true; 1175 } 1176 } else if ((*Mem)->isImplicit()) { 1177 // Any implicit members are fine. 1178 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1179 // This is a type that showed up in an 1180 // elaborated-type-specifier inside the anonymous struct or 1181 // union, but which actually declares a type outside of the 1182 // anonymous struct or union. It's okay. 1183 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1184 if (!MemRecord->isAnonymousStructOrUnion() && 1185 MemRecord->getDeclName()) { 1186 // This is a nested type declaration. 1187 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1188 << (int)Record->isUnion(); 1189 Invalid = true; 1190 } 1191 } else { 1192 // We have something that isn't a non-static data 1193 // member. Complain about it. 1194 unsigned DK = diag::err_anonymous_record_bad_member; 1195 if (isa<TypeDecl>(*Mem)) 1196 DK = diag::err_anonymous_record_with_type; 1197 else if (isa<FunctionDecl>(*Mem)) 1198 DK = diag::err_anonymous_record_with_function; 1199 else if (isa<VarDecl>(*Mem)) 1200 DK = diag::err_anonymous_record_with_static; 1201 Diag((*Mem)->getLocation(), DK) 1202 << (int)Record->isUnion(); 1203 Invalid = true; 1204 } 1205 } 1206 } 1207 1208 if (!Record->isUnion() && !Owner->isRecord()) { 1209 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1210 << (int)getLangOptions().CPlusPlus; 1211 Invalid = true; 1212 } 1213 1214 // Create a declaration for this anonymous struct/union. 1215 NamedDecl *Anon = 0; 1216 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1217 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1218 /*IdentifierInfo=*/0, 1219 Context.getTypeDeclType(Record), 1220 /*BitWidth=*/0, /*Mutable=*/false); 1221 Anon->setAccess(AS_public); 1222 if (getLangOptions().CPlusPlus) 1223 FieldCollector->Add(cast<FieldDecl>(Anon)); 1224 } else { 1225 VarDecl::StorageClass SC; 1226 switch (DS.getStorageClassSpec()) { 1227 default: assert(0 && "Unknown storage class!"); 1228 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1229 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1230 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1231 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1232 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1233 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1234 case DeclSpec::SCS_mutable: 1235 // mutable can only appear on non-static class members, so it's always 1236 // an error here 1237 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1238 Invalid = true; 1239 SC = VarDecl::None; 1240 break; 1241 } 1242 1243 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1244 /*IdentifierInfo=*/0, 1245 Context.getTypeDeclType(Record), 1246 SC, DS.getSourceRange().getBegin()); 1247 } 1248 Anon->setImplicit(); 1249 1250 // Add the anonymous struct/union object to the current 1251 // context. We'll be referencing this object when we refer to one of 1252 // its members. 1253 Owner->addDecl(Context, Anon); 1254 1255 // Inject the members of the anonymous struct/union into the owning 1256 // context and into the identifier resolver chain for name lookup 1257 // purposes. 1258 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1259 Invalid = true; 1260 1261 // Mark this as an anonymous struct/union type. Note that we do not 1262 // do this until after we have already checked and injected the 1263 // members of this anonymous struct/union type, because otherwise 1264 // the members could be injected twice: once by DeclContext when it 1265 // builds its lookup table, and once by 1266 // InjectAnonymousStructOrUnionMembers. 1267 Record->setAnonymousStructOrUnion(true); 1268 1269 if (Invalid) 1270 Anon->setInvalidDecl(); 1271 1272 return DeclPtrTy::make(Anon); 1273} 1274 1275 1276/// GetNameForDeclarator - Determine the full declaration name for the 1277/// given Declarator. 1278DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1279 switch (D.getKind()) { 1280 case Declarator::DK_Abstract: 1281 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1282 return DeclarationName(); 1283 1284 case Declarator::DK_Normal: 1285 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1286 return DeclarationName(D.getIdentifier()); 1287 1288 case Declarator::DK_Constructor: { 1289 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1290 Ty = Context.getCanonicalType(Ty); 1291 return Context.DeclarationNames.getCXXConstructorName(Ty); 1292 } 1293 1294 case Declarator::DK_Destructor: { 1295 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1296 Ty = Context.getCanonicalType(Ty); 1297 return Context.DeclarationNames.getCXXDestructorName(Ty); 1298 } 1299 1300 case Declarator::DK_Conversion: { 1301 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1302 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1303 Ty = Context.getCanonicalType(Ty); 1304 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1305 } 1306 1307 case Declarator::DK_Operator: 1308 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1309 return Context.DeclarationNames.getCXXOperatorName( 1310 D.getOverloadedOperator()); 1311 } 1312 1313 assert(false && "Unknown name kind"); 1314 return DeclarationName(); 1315} 1316 1317/// isNearlyMatchingFunction - Determine whether the C++ functions 1318/// Declaration and Definition are "nearly" matching. This heuristic 1319/// is used to improve diagnostics in the case where an out-of-line 1320/// function definition doesn't match any declaration within 1321/// the class or namespace. 1322static bool isNearlyMatchingFunction(ASTContext &Context, 1323 FunctionDecl *Declaration, 1324 FunctionDecl *Definition) { 1325 if (Declaration->param_size() != Definition->param_size()) 1326 return false; 1327 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1328 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1329 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1330 1331 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1332 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1333 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1334 return false; 1335 } 1336 1337 return true; 1338} 1339 1340Sema::DeclPtrTy 1341Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1342 DeclarationName Name = GetNameForDeclarator(D); 1343 1344 // All of these full declarators require an identifier. If it doesn't have 1345 // one, the ParsedFreeStandingDeclSpec action should be used. 1346 if (!Name) { 1347 if (!D.isInvalidType()) // Reject this if we think it is valid. 1348 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1349 diag::err_declarator_need_ident) 1350 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1351 return DeclPtrTy(); 1352 } 1353 1354 // The scope passed in may not be a decl scope. Zip up the scope tree until 1355 // we find one that is. 1356 while ((S->getFlags() & Scope::DeclScope) == 0 || 1357 (S->getFlags() & Scope::TemplateParamScope) != 0) 1358 S = S->getParent(); 1359 1360 DeclContext *DC; 1361 NamedDecl *PrevDecl; 1362 NamedDecl *New; 1363 1364 QualType R = GetTypeForDeclarator(D, S); 1365 1366 // See if this is a redefinition of a variable in the same scope. 1367 if (D.getCXXScopeSpec().isInvalid()) { 1368 DC = CurContext; 1369 PrevDecl = 0; 1370 D.setInvalidType(); 1371 } else if (!D.getCXXScopeSpec().isSet()) { 1372 LookupNameKind NameKind = LookupOrdinaryName; 1373 1374 // If the declaration we're planning to build will be a function 1375 // or object with linkage, then look for another declaration with 1376 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1377 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1378 /* Do nothing*/; 1379 else if (R->isFunctionType()) { 1380 if (CurContext->isFunctionOrMethod()) 1381 NameKind = LookupRedeclarationWithLinkage; 1382 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1383 NameKind = LookupRedeclarationWithLinkage; 1384 1385 DC = CurContext; 1386 PrevDecl = LookupName(S, Name, NameKind, true, 1387 D.getDeclSpec().getStorageClassSpec() != 1388 DeclSpec::SCS_static, 1389 D.getIdentifierLoc()); 1390 } else { // Something like "int foo::x;" 1391 DC = computeDeclContext(D.getCXXScopeSpec()); 1392 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1393 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1394 1395 // C++ 7.3.1.2p2: 1396 // Members (including explicit specializations of templates) of a named 1397 // namespace can also be defined outside that namespace by explicit 1398 // qualification of the name being defined, provided that the entity being 1399 // defined was already declared in the namespace and the definition appears 1400 // after the point of declaration in a namespace that encloses the 1401 // declarations namespace. 1402 // 1403 // Note that we only check the context at this point. We don't yet 1404 // have enough information to make sure that PrevDecl is actually 1405 // the declaration we want to match. For example, given: 1406 // 1407 // class X { 1408 // void f(); 1409 // void f(float); 1410 // }; 1411 // 1412 // void X::f(int) { } // ill-formed 1413 // 1414 // In this case, PrevDecl will point to the overload set 1415 // containing the two f's declared in X, but neither of them 1416 // matches. 1417 1418 // First check whether we named the global scope. 1419 if (isa<TranslationUnitDecl>(DC)) { 1420 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1421 << Name << D.getCXXScopeSpec().getRange(); 1422 } else if (!CurContext->Encloses(DC)) { 1423 // The qualifying scope doesn't enclose the original declaration. 1424 // Emit diagnostic based on current scope. 1425 SourceLocation L = D.getIdentifierLoc(); 1426 SourceRange R = D.getCXXScopeSpec().getRange(); 1427 if (isa<FunctionDecl>(CurContext)) 1428 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1429 else 1430 Diag(L, diag::err_invalid_declarator_scope) 1431 << Name << cast<NamedDecl>(DC) << R; 1432 D.setInvalidType(); 1433 } 1434 } 1435 1436 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1437 // Maybe we will complain about the shadowed template parameter. 1438 if (!D.isInvalidType()) 1439 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1440 D.setInvalidType(); 1441 1442 // Just pretend that we didn't see the previous declaration. 1443 PrevDecl = 0; 1444 } 1445 1446 // In C++, the previous declaration we find might be a tag type 1447 // (class or enum). In this case, the new declaration will hide the 1448 // tag type. Note that this does does not apply if we're declaring a 1449 // typedef (C++ [dcl.typedef]p4). 1450 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1451 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1452 PrevDecl = 0; 1453 1454 bool Redeclaration = false; 1455 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1456 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1457 } else if (R->isFunctionType()) { 1458 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1459 IsFunctionDefinition, Redeclaration); 1460 } else { 1461 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1462 } 1463 1464 if (New == 0) 1465 return DeclPtrTy(); 1466 1467 // If this has an identifier and is not an invalid redeclaration, 1468 // add it to the scope stack. 1469 if (Name && !(Redeclaration && New->isInvalidDecl())) 1470 PushOnScopeChains(New, S); 1471 1472 return DeclPtrTy::make(New); 1473} 1474 1475/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1476/// types into constant array types in certain situations which would otherwise 1477/// be errors (for GCC compatibility). 1478static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1479 ASTContext &Context, 1480 bool &SizeIsNegative) { 1481 // This method tries to turn a variable array into a constant 1482 // array even when the size isn't an ICE. This is necessary 1483 // for compatibility with code that depends on gcc's buggy 1484 // constant expression folding, like struct {char x[(int)(char*)2];} 1485 SizeIsNegative = false; 1486 1487 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1488 QualType Pointee = PTy->getPointeeType(); 1489 QualType FixedType = 1490 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1491 if (FixedType.isNull()) return FixedType; 1492 FixedType = Context.getPointerType(FixedType); 1493 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1494 return FixedType; 1495 } 1496 1497 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1498 if (!VLATy) 1499 return QualType(); 1500 // FIXME: We should probably handle this case 1501 if (VLATy->getElementType()->isVariablyModifiedType()) 1502 return QualType(); 1503 1504 Expr::EvalResult EvalResult; 1505 if (!VLATy->getSizeExpr() || 1506 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1507 !EvalResult.Val.isInt()) 1508 return QualType(); 1509 1510 llvm::APSInt &Res = EvalResult.Val.getInt(); 1511 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1512 return Context.getConstantArrayType(VLATy->getElementType(), 1513 Res, ArrayType::Normal, 0); 1514 1515 SizeIsNegative = true; 1516 return QualType(); 1517} 1518 1519/// \brief Register the given locally-scoped external C declaration so 1520/// that it can be found later for redeclarations 1521void 1522Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1523 Scope *S) { 1524 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1525 "Decl is not a locally-scoped decl!"); 1526 // Note that we have a locally-scoped external with this name. 1527 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1528 1529 if (!PrevDecl) 1530 return; 1531 1532 // If there was a previous declaration of this variable, it may be 1533 // in our identifier chain. Update the identifier chain with the new 1534 // declaration. 1535 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1536 // The previous declaration was found on the identifer resolver 1537 // chain, so remove it from its scope. 1538 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1539 S = S->getParent(); 1540 1541 if (S) 1542 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1543 } 1544} 1545 1546/// \brief Diagnose function specifiers on a declaration of an identifier that 1547/// does not identify a function. 1548void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1549 // FIXME: We should probably indicate the identifier in question to avoid 1550 // confusion for constructs like "inline int a(), b;" 1551 if (D.getDeclSpec().isInlineSpecified()) 1552 Diag(D.getDeclSpec().getInlineSpecLoc(), 1553 diag::err_inline_non_function); 1554 1555 if (D.getDeclSpec().isVirtualSpecified()) 1556 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1557 diag::err_virtual_non_function); 1558 1559 if (D.getDeclSpec().isExplicitSpecified()) 1560 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1561 diag::err_explicit_non_function); 1562} 1563 1564NamedDecl* 1565Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1566 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1567 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1568 if (D.getCXXScopeSpec().isSet()) { 1569 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1570 << D.getCXXScopeSpec().getRange(); 1571 D.setInvalidType(); 1572 // Pretend we didn't see the scope specifier. 1573 DC = 0; 1574 } 1575 1576 if (getLangOptions().CPlusPlus) { 1577 // Check that there are no default arguments (C++ only). 1578 CheckExtraCXXDefaultArguments(D); 1579 } 1580 1581 DiagnoseFunctionSpecifiers(D); 1582 1583 if (D.getDeclSpec().isThreadSpecified()) 1584 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1585 1586 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1587 if (!NewTD) return 0; 1588 1589 if (D.isInvalidType()) 1590 NewTD->setInvalidDecl(); 1591 1592 // Handle attributes prior to checking for duplicates in MergeVarDecl 1593 ProcessDeclAttributes(NewTD, D); 1594 // Merge the decl with the existing one if appropriate. If the decl is 1595 // in an outer scope, it isn't the same thing. 1596 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1597 Redeclaration = true; 1598 MergeTypeDefDecl(NewTD, PrevDecl); 1599 } 1600 1601 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1602 // then it shall have block scope. 1603 QualType T = NewTD->getUnderlyingType(); 1604 if (T->isVariablyModifiedType()) { 1605 CurFunctionNeedsScopeChecking = true; 1606 1607 if (S->getFnParent() == 0) { 1608 bool SizeIsNegative; 1609 QualType FixedTy = 1610 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1611 if (!FixedTy.isNull()) { 1612 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1613 NewTD->setUnderlyingType(FixedTy); 1614 } else { 1615 if (SizeIsNegative) 1616 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1617 else if (T->isVariableArrayType()) 1618 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1619 else 1620 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1621 NewTD->setInvalidDecl(); 1622 } 1623 } 1624 } 1625 return NewTD; 1626} 1627 1628/// \brief Determines whether the given declaration is an out-of-scope 1629/// previous declaration. 1630/// 1631/// This routine should be invoked when name lookup has found a 1632/// previous declaration (PrevDecl) that is not in the scope where a 1633/// new declaration by the same name is being introduced. If the new 1634/// declaration occurs in a local scope, previous declarations with 1635/// linkage may still be considered previous declarations (C99 1636/// 6.2.2p4-5, C++ [basic.link]p6). 1637/// 1638/// \param PrevDecl the previous declaration found by name 1639/// lookup 1640/// 1641/// \param DC the context in which the new declaration is being 1642/// declared. 1643/// 1644/// \returns true if PrevDecl is an out-of-scope previous declaration 1645/// for a new delcaration with the same name. 1646static bool 1647isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1648 ASTContext &Context) { 1649 if (!PrevDecl) 1650 return 0; 1651 1652 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1653 // case we need to check each of the overloaded functions. 1654 if (!PrevDecl->hasLinkage()) 1655 return false; 1656 1657 if (Context.getLangOptions().CPlusPlus) { 1658 // C++ [basic.link]p6: 1659 // If there is a visible declaration of an entity with linkage 1660 // having the same name and type, ignoring entities declared 1661 // outside the innermost enclosing namespace scope, the block 1662 // scope declaration declares that same entity and receives the 1663 // linkage of the previous declaration. 1664 DeclContext *OuterContext = DC->getLookupContext(); 1665 if (!OuterContext->isFunctionOrMethod()) 1666 // This rule only applies to block-scope declarations. 1667 return false; 1668 else { 1669 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1670 if (PrevOuterContext->isRecord()) 1671 // We found a member function: ignore it. 1672 return false; 1673 else { 1674 // Find the innermost enclosing namespace for the new and 1675 // previous declarations. 1676 while (!OuterContext->isFileContext()) 1677 OuterContext = OuterContext->getParent(); 1678 while (!PrevOuterContext->isFileContext()) 1679 PrevOuterContext = PrevOuterContext->getParent(); 1680 1681 // The previous declaration is in a different namespace, so it 1682 // isn't the same function. 1683 if (OuterContext->getPrimaryContext() != 1684 PrevOuterContext->getPrimaryContext()) 1685 return false; 1686 } 1687 } 1688 } 1689 1690 return true; 1691} 1692 1693NamedDecl* 1694Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1695 QualType R,NamedDecl* PrevDecl, 1696 bool &Redeclaration) { 1697 DeclarationName Name = GetNameForDeclarator(D); 1698 1699 // Check that there are no default arguments (C++ only). 1700 if (getLangOptions().CPlusPlus) 1701 CheckExtraCXXDefaultArguments(D); 1702 1703 VarDecl *NewVD; 1704 VarDecl::StorageClass SC; 1705 switch (D.getDeclSpec().getStorageClassSpec()) { 1706 default: assert(0 && "Unknown storage class!"); 1707 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1708 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1709 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1710 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1711 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1712 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1713 case DeclSpec::SCS_mutable: 1714 // mutable can only appear on non-static class members, so it's always 1715 // an error here 1716 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1717 D.setInvalidType(); 1718 SC = VarDecl::None; 1719 break; 1720 } 1721 1722 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1723 if (!II) { 1724 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1725 << Name.getAsString(); 1726 return 0; 1727 } 1728 1729 DiagnoseFunctionSpecifiers(D); 1730 1731 if (!DC->isRecord() && S->getFnParent() == 0) { 1732 // C99 6.9p2: The storage-class specifiers auto and register shall not 1733 // appear in the declaration specifiers in an external declaration. 1734 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1735 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1736 D.setInvalidType(); 1737 } 1738 } 1739 if (DC->isRecord() && !CurContext->isRecord()) { 1740 // This is an out-of-line definition of a static data member. 1741 if (SC == VarDecl::Static) { 1742 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1743 diag::err_static_out_of_line) 1744 << CodeModificationHint::CreateRemoval( 1745 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1746 } else if (SC == VarDecl::None) 1747 SC = VarDecl::Static; 1748 } 1749 1750 // The variable can not 1751 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1752 II, R, SC, 1753 // FIXME: Move to DeclGroup... 1754 D.getDeclSpec().getSourceRange().getBegin()); 1755 1756 if (D.isInvalidType()) 1757 NewVD->setInvalidDecl(); 1758 1759 if (D.getDeclSpec().isThreadSpecified()) { 1760 if (NewVD->hasLocalStorage()) 1761 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1762 else if (!Context.Target.isTLSSupported()) 1763 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1764 else 1765 NewVD->setThreadSpecified(true); 1766 } 1767 1768 // Set the lexical context. If the declarator has a C++ scope specifier, the 1769 // lexical context will be different from the semantic context. 1770 NewVD->setLexicalDeclContext(CurContext); 1771 1772 // Handle attributes prior to checking for duplicates in MergeVarDecl 1773 ProcessDeclAttributes(NewVD, D); 1774 1775 // Handle GNU asm-label extension (encoded as an attribute). 1776 if (Expr *E = (Expr*) D.getAsmLabel()) { 1777 // The parser guarantees this is a string. 1778 StringLiteral *SE = cast<StringLiteral>(E); 1779 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1780 SE->getByteLength()))); 1781 } 1782 1783 // If name lookup finds a previous declaration that is not in the 1784 // same scope as the new declaration, this may still be an 1785 // acceptable redeclaration. 1786 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1787 !(NewVD->hasLinkage() && 1788 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1789 PrevDecl = 0; 1790 1791 // Merge the decl with the existing one if appropriate. 1792 if (PrevDecl) { 1793 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1794 // The user tried to define a non-static data member 1795 // out-of-line (C++ [dcl.meaning]p1). 1796 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1797 << D.getCXXScopeSpec().getRange(); 1798 PrevDecl = 0; 1799 NewVD->setInvalidDecl(); 1800 } 1801 } else if (D.getCXXScopeSpec().isSet()) { 1802 // No previous declaration in the qualifying scope. 1803 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1804 << Name << D.getCXXScopeSpec().getRange(); 1805 NewVD->setInvalidDecl(); 1806 } 1807 1808 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1809 1810 // If this is a locally-scoped extern C variable, update the map of 1811 // such variables. 1812 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1813 !NewVD->isInvalidDecl()) 1814 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1815 1816 return NewVD; 1817} 1818 1819/// \brief Perform semantic checking on a newly-created variable 1820/// declaration. 1821/// 1822/// This routine performs all of the type-checking required for a 1823/// variable declaration once it has been build. It is used both to 1824/// check variables after they have been parsed and their declarators 1825/// have been translated into a declaration, and to check 1826/// 1827/// Sets NewVD->isInvalidDecl() if an error was encountered. 1828void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1829 bool &Redeclaration) { 1830 // If the decl is already known invalid, don't check it. 1831 if (NewVD->isInvalidDecl()) 1832 return; 1833 1834 QualType T = NewVD->getType(); 1835 1836 if (T->isObjCInterfaceType()) { 1837 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1838 return NewVD->setInvalidDecl(); 1839 } 1840 1841 // The variable can not have an abstract class type. 1842 if (RequireNonAbstractType(NewVD->getLocation(), T, 1843 diag::err_abstract_type_in_decl, 1844 AbstractVariableType)) 1845 return NewVD->setInvalidDecl(); 1846 1847 // Emit an error if an address space was applied to decl with local storage. 1848 // This includes arrays of objects with address space qualifiers, but not 1849 // automatic variables that point to other address spaces. 1850 // ISO/IEC TR 18037 S5.1.2 1851 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1852 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1853 return NewVD->setInvalidDecl(); 1854 } 1855 1856 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1857 && !NewVD->hasAttr<BlocksAttr>()) 1858 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1859 1860 bool isVM = T->isVariablyModifiedType(); 1861 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1862 CurFunctionNeedsScopeChecking = true; 1863 1864 if ((isVM && NewVD->hasLinkage()) || 1865 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1866 bool SizeIsNegative; 1867 QualType FixedTy = 1868 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1869 1870 if (FixedTy.isNull() && T->isVariableArrayType()) { 1871 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1872 // FIXME: This won't give the correct result for 1873 // int a[10][n]; 1874 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1875 1876 if (NewVD->isFileVarDecl()) 1877 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1878 << SizeRange; 1879 else if (NewVD->getStorageClass() == VarDecl::Static) 1880 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1881 << SizeRange; 1882 else 1883 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1884 << SizeRange; 1885 return NewVD->setInvalidDecl(); 1886 } 1887 1888 if (FixedTy.isNull()) { 1889 if (NewVD->isFileVarDecl()) 1890 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1891 else 1892 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1893 return NewVD->setInvalidDecl(); 1894 } 1895 1896 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1897 NewVD->setType(FixedTy); 1898 } 1899 1900 if (!PrevDecl && NewVD->isExternC(Context)) { 1901 // Since we did not find anything by this name and we're declaring 1902 // an extern "C" variable, look for a non-visible extern "C" 1903 // declaration with the same name. 1904 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1905 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1906 if (Pos != LocallyScopedExternalDecls.end()) 1907 PrevDecl = Pos->second; 1908 } 1909 1910 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1911 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1912 << T; 1913 return NewVD->setInvalidDecl(); 1914 } 1915 1916 if (PrevDecl) { 1917 Redeclaration = true; 1918 MergeVarDecl(NewVD, PrevDecl); 1919 } 1920} 1921 1922NamedDecl* 1923Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1924 QualType R, NamedDecl* PrevDecl, 1925 bool IsFunctionDefinition, bool &Redeclaration) { 1926 assert(R.getTypePtr()->isFunctionType()); 1927 1928 DeclarationName Name = GetNameForDeclarator(D); 1929 FunctionDecl::StorageClass SC = FunctionDecl::None; 1930 switch (D.getDeclSpec().getStorageClassSpec()) { 1931 default: assert(0 && "Unknown storage class!"); 1932 case DeclSpec::SCS_auto: 1933 case DeclSpec::SCS_register: 1934 case DeclSpec::SCS_mutable: 1935 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1936 diag::err_typecheck_sclass_func); 1937 D.setInvalidType(); 1938 break; 1939 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1940 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1941 case DeclSpec::SCS_static: { 1942 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1943 // C99 6.7.1p5: 1944 // The declaration of an identifier for a function that has 1945 // block scope shall have no explicit storage-class specifier 1946 // other than extern 1947 // See also (C++ [dcl.stc]p4). 1948 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1949 diag::err_static_block_func); 1950 SC = FunctionDecl::None; 1951 } else 1952 SC = FunctionDecl::Static; 1953 break; 1954 } 1955 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1956 } 1957 1958 if (D.getDeclSpec().isThreadSpecified()) 1959 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1960 1961 bool isInline = D.getDeclSpec().isInlineSpecified(); 1962 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1963 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1964 1965 // Check that the return type is not an abstract class type. 1966 // For record types, this is done by the AbstractClassUsageDiagnoser once 1967 // the class has been completely parsed. 1968 if (!DC->isRecord() && 1969 RequireNonAbstractType(D.getIdentifierLoc(), 1970 R->getAsFunctionType()->getResultType(), 1971 diag::err_abstract_type_in_decl, 1972 AbstractReturnType)) 1973 D.setInvalidType(); 1974 1975 // Do not allow returning a objc interface by-value. 1976 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1977 Diag(D.getIdentifierLoc(), 1978 diag::err_object_cannot_be_passed_returned_by_value) << 0 1979 << R->getAsFunctionType()->getResultType(); 1980 D.setInvalidType(); 1981 } 1982 1983 bool isVirtualOkay = false; 1984 FunctionDecl *NewFD; 1985 if (D.getKind() == Declarator::DK_Constructor) { 1986 // This is a C++ constructor declaration. 1987 assert(DC->isRecord() && 1988 "Constructors can only be declared in a member context"); 1989 1990 R = CheckConstructorDeclarator(D, R, SC); 1991 1992 // Create the new declaration 1993 NewFD = CXXConstructorDecl::Create(Context, 1994 cast<CXXRecordDecl>(DC), 1995 D.getIdentifierLoc(), Name, R, 1996 isExplicit, isInline, 1997 /*isImplicitlyDeclared=*/false); 1998 } else if (D.getKind() == Declarator::DK_Destructor) { 1999 // This is a C++ destructor declaration. 2000 if (DC->isRecord()) { 2001 R = CheckDestructorDeclarator(D, SC); 2002 2003 NewFD = CXXDestructorDecl::Create(Context, 2004 cast<CXXRecordDecl>(DC), 2005 D.getIdentifierLoc(), Name, R, 2006 isInline, 2007 /*isImplicitlyDeclared=*/false); 2008 2009 isVirtualOkay = true; 2010 } else { 2011 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2012 2013 // Create a FunctionDecl to satisfy the function definition parsing 2014 // code path. 2015 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2016 Name, R, SC, isInline, 2017 /*hasPrototype=*/true, 2018 // FIXME: Move to DeclGroup... 2019 D.getDeclSpec().getSourceRange().getBegin()); 2020 D.setInvalidType(); 2021 } 2022 } else if (D.getKind() == Declarator::DK_Conversion) { 2023 if (!DC->isRecord()) { 2024 Diag(D.getIdentifierLoc(), 2025 diag::err_conv_function_not_member); 2026 return 0; 2027 } 2028 2029 CheckConversionDeclarator(D, R, SC); 2030 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2031 D.getIdentifierLoc(), Name, R, 2032 isInline, isExplicit); 2033 2034 isVirtualOkay = true; 2035 } else if (DC->isRecord()) { 2036 // This is a C++ method declaration. 2037 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2038 D.getIdentifierLoc(), Name, R, 2039 (SC == FunctionDecl::Static), isInline); 2040 2041 isVirtualOkay = (SC != FunctionDecl::Static); 2042 } else { 2043 // Determine whether the function was written with a 2044 // prototype. This true when: 2045 // - we're in C++ (where every function has a prototype), 2046 // - there is a prototype in the declarator, or 2047 // - the type R of the function is some kind of typedef or other reference 2048 // to a type name (which eventually refers to a function type). 2049 bool HasPrototype = 2050 getLangOptions().CPlusPlus || 2051 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2052 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2053 2054 NewFD = FunctionDecl::Create(Context, DC, 2055 D.getIdentifierLoc(), 2056 Name, R, SC, isInline, HasPrototype, 2057 // FIXME: Move to DeclGroup... 2058 D.getDeclSpec().getSourceRange().getBegin()); 2059 } 2060 2061 if (D.isInvalidType()) 2062 NewFD->setInvalidDecl(); 2063 2064 // Set the lexical context. If the declarator has a C++ 2065 // scope specifier, the lexical context will be different 2066 // from the semantic context. 2067 NewFD->setLexicalDeclContext(CurContext); 2068 2069 // C++ [dcl.fct.spec]p5: 2070 // The virtual specifier shall only be used in declarations of 2071 // nonstatic class member functions that appear within a 2072 // member-specification of a class declaration; see 10.3. 2073 // 2074 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2075 // function is also virtual if it overrides an already virtual 2076 // function. This is important to do here because it's part of the 2077 // declaration. 2078 if (isVirtual && !NewFD->isInvalidDecl()) { 2079 if (!isVirtualOkay) { 2080 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2081 diag::err_virtual_non_function); 2082 } else if (!CurContext->isRecord()) { 2083 // 'virtual' was specified outside of the class. 2084 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2085 << CodeModificationHint::CreateRemoval( 2086 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2087 } else { 2088 // Okay: Add virtual to the method. 2089 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2090 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2091 CurClass->setAggregate(false); 2092 CurClass->setPOD(false); 2093 CurClass->setPolymorphic(true); 2094 CurClass->setHasTrivialConstructor(false); 2095 } 2096 } 2097 2098 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2099 !CurContext->isRecord()) { 2100 // C++ [class.static]p1: 2101 // A data or function member of a class may be declared static 2102 // in a class definition, in which case it is a static member of 2103 // the class. 2104 2105 // Complain about the 'static' specifier if it's on an out-of-line 2106 // member function definition. 2107 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2108 diag::err_static_out_of_line) 2109 << CodeModificationHint::CreateRemoval( 2110 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2111 } 2112 2113 // Handle GNU asm-label extension (encoded as an attribute). 2114 if (Expr *E = (Expr*) D.getAsmLabel()) { 2115 // The parser guarantees this is a string. 2116 StringLiteral *SE = cast<StringLiteral>(E); 2117 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2118 SE->getByteLength()))); 2119 } 2120 2121 // Copy the parameter declarations from the declarator D to the function 2122 // declaration NewFD, if they are available. First scavenge them into Params. 2123 llvm::SmallVector<ParmVarDecl*, 16> Params; 2124 if (D.getNumTypeObjects() > 0) { 2125 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2126 2127 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2128 // function that takes no arguments, not a function that takes a 2129 // single void argument. 2130 // We let through "const void" here because Sema::GetTypeForDeclarator 2131 // already checks for that case. 2132 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2133 FTI.ArgInfo[0].Param && 2134 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2135 // Empty arg list, don't push any params. 2136 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2137 2138 // In C++, the empty parameter-type-list must be spelled "void"; a 2139 // typedef of void is not permitted. 2140 if (getLangOptions().CPlusPlus && 2141 Param->getType().getUnqualifiedType() != Context.VoidTy) 2142 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2143 // FIXME: Leaks decl? 2144 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2145 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2146 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2147 } 2148 2149 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2150 // When we're declaring a function with a typedef, typeof, etc as in the 2151 // following example, we'll need to synthesize (unnamed) 2152 // parameters for use in the declaration. 2153 // 2154 // @code 2155 // typedef void fn(int); 2156 // fn f; 2157 // @endcode 2158 2159 // Synthesize a parameter for each argument type. 2160 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2161 AE = FT->arg_type_end(); AI != AE; ++AI) { 2162 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2163 SourceLocation(), 0, 2164 *AI, VarDecl::None, 0); 2165 Param->setImplicit(); 2166 Params.push_back(Param); 2167 } 2168 } else { 2169 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2170 "Should not need args for typedef of non-prototype fn"); 2171 } 2172 // Finally, we know we have the right number of parameters, install them. 2173 NewFD->setParams(Context, &Params[0], Params.size()); 2174 2175 2176 2177 // If name lookup finds a previous declaration that is not in the 2178 // same scope as the new declaration, this may still be an 2179 // acceptable redeclaration. 2180 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2181 !(NewFD->hasLinkage() && 2182 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2183 PrevDecl = 0; 2184 2185 // FIXME: We need to determine whether the GNU inline attribute will 2186 // be applied to this function declaration, since it affects 2187 // declaration merging. This hack will go away when the FIXME below 2188 // is resolved, since we should be putting *all* attributes onto the 2189 // declaration now. 2190 for (const AttributeList *Attr = D.getDeclSpec().getAttributes(); 2191 Attr; Attr = Attr->getNext()) { 2192 if (Attr->getKind() == AttributeList::AT_gnu_inline) { 2193 NewFD->addAttr(::new (Context) GNUInlineAttr()); 2194 break; 2195 } 2196 } 2197 2198 // Perform semantic checking on the function declaration. 2199 bool OverloadableAttrRequired = false; // FIXME: HACK! 2200 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2201 /*FIXME:*/OverloadableAttrRequired); 2202 2203 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2204 // An out-of-line member function declaration must also be a 2205 // definition (C++ [dcl.meaning]p1). 2206 if (!IsFunctionDefinition) { 2207 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2208 << D.getCXXScopeSpec().getRange(); 2209 NewFD->setInvalidDecl(); 2210 } else if (!Redeclaration) { 2211 // The user tried to provide an out-of-line definition for a 2212 // function that is a member of a class or namespace, but there 2213 // was no such member function declared (C++ [class.mfct]p2, 2214 // C++ [namespace.memdef]p2). For example: 2215 // 2216 // class X { 2217 // void f() const; 2218 // }; 2219 // 2220 // void X::f() { } // ill-formed 2221 // 2222 // Complain about this problem, and attempt to suggest close 2223 // matches (e.g., those that differ only in cv-qualifiers and 2224 // whether the parameter types are references). 2225 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2226 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2227 NewFD->setInvalidDecl(); 2228 2229 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2230 true); 2231 assert(!Prev.isAmbiguous() && 2232 "Cannot have an ambiguity in previous-declaration lookup"); 2233 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2234 Func != FuncEnd; ++Func) { 2235 if (isa<FunctionDecl>(*Func) && 2236 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2237 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2238 } 2239 2240 PrevDecl = 0; 2241 } 2242 } 2243 2244 // Handle attributes. We need to have merged decls when handling attributes 2245 // (for example to check for conflicts, etc). 2246 // FIXME: This needs to happen before we merge declarations. Then, 2247 // let attribute merging cope with attribute conflicts. 2248 ProcessDeclAttributes(NewFD, D); 2249 AddKnownFunctionAttributes(NewFD); 2250 2251 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2252 // If a function name is overloadable in C, then every function 2253 // with that name must be marked "overloadable". 2254 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2255 << Redeclaration << NewFD; 2256 if (PrevDecl) 2257 Diag(PrevDecl->getLocation(), 2258 diag::note_attribute_overloadable_prev_overload); 2259 NewFD->addAttr(::new (Context) OverloadableAttr()); 2260 } 2261 2262 // If this is a locally-scoped extern C function, update the 2263 // map of such names. 2264 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2265 && !NewFD->isInvalidDecl()) 2266 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2267 2268 return NewFD; 2269} 2270 2271/// \brief Perform semantic checking of a new function declaration. 2272/// 2273/// Performs semantic analysis of the new function declaration 2274/// NewFD. This routine performs all semantic checking that does not 2275/// require the actual declarator involved in the declaration, and is 2276/// used both for the declaration of functions as they are parsed 2277/// (called via ActOnDeclarator) and for the declaration of functions 2278/// that have been instantiated via C++ template instantiation (called 2279/// via InstantiateDecl). 2280/// 2281/// This sets NewFD->isInvalidDecl() to true if there was an error. 2282void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2283 bool &Redeclaration, 2284 bool &OverloadableAttrRequired) { 2285 // If NewFD is already known erroneous, don't do any of this checking. 2286 if (NewFD->isInvalidDecl()) 2287 return; 2288 2289 // Semantic checking for this function declaration (in isolation). 2290 if (getLangOptions().CPlusPlus) { 2291 // C++-specific checks. 2292 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2293 CheckConstructor(Constructor); 2294 } else if (isa<CXXDestructorDecl>(NewFD)) { 2295 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2296 Record->setUserDeclaredDestructor(true); 2297 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2298 // user-defined destructor. 2299 Record->setPOD(false); 2300 2301 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2302 // declared destructor. 2303 Record->setHasTrivialDestructor(false); 2304 } else if (CXXConversionDecl *Conversion 2305 = dyn_cast<CXXConversionDecl>(NewFD)) 2306 ActOnConversionDeclarator(Conversion); 2307 2308 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2309 if (NewFD->isOverloadedOperator() && 2310 CheckOverloadedOperatorDeclaration(NewFD)) 2311 return NewFD->setInvalidDecl(); 2312 } 2313 2314 // C99 6.7.4p6: 2315 // [... ] For a function with external linkage, the following 2316 // restrictions apply: [...] If all of the file scope declarations 2317 // for a function in a translation unit include the inline 2318 // function specifier without extern, then the definition in that 2319 // translation unit is an inline definition. An inline definition 2320 // does not provide an external definition for the function, and 2321 // does not forbid an external definition in another translation 2322 // unit. 2323 // 2324 // Here we determine whether this function, in isolation, would be a 2325 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2326 // previous declarations. 2327 if (NewFD->isInline() && 2328 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2329 bool GNUInline = NewFD->hasAttr<GNUInlineAttr>() || 2330 (PrevDecl && PrevDecl->hasAttr<GNUInlineAttr>()); 2331 if (GNUInline || (!getLangOptions().CPlusPlus && !getLangOptions().C99)) { 2332 // GNU "extern inline" is the same as "inline" in C99. 2333 if (NewFD->getStorageClass() == FunctionDecl::Extern) 2334 NewFD->setC99InlineDefinition(true); 2335 } else if (getLangOptions().C99 && 2336 NewFD->getStorageClass() == FunctionDecl::None) 2337 NewFD->setC99InlineDefinition(true); 2338 } 2339 2340 // Check for a previous declaration of this name. 2341 if (!PrevDecl && NewFD->isExternC(Context)) { 2342 // Since we did not find anything by this name and we're declaring 2343 // an extern "C" function, look for a non-visible extern "C" 2344 // declaration with the same name. 2345 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2346 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2347 if (Pos != LocallyScopedExternalDecls.end()) 2348 PrevDecl = Pos->second; 2349 } 2350 2351 // Merge or overload the declaration with an existing declaration of 2352 // the same name, if appropriate. 2353 if (PrevDecl) { 2354 // Determine whether NewFD is an overload of PrevDecl or 2355 // a declaration that requires merging. If it's an overload, 2356 // there's no more work to do here; we'll just add the new 2357 // function to the scope. 2358 OverloadedFunctionDecl::function_iterator MatchedDecl; 2359 2360 if (!getLangOptions().CPlusPlus && 2361 AllowOverloadingOfFunction(PrevDecl, Context)) { 2362 OverloadableAttrRequired = true; 2363 2364 // Functions marked "overloadable" must have a prototype (that 2365 // we can't get through declaration merging). 2366 if (!NewFD->getType()->getAsFunctionProtoType()) { 2367 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2368 << NewFD; 2369 Redeclaration = true; 2370 2371 // Turn this into a variadic function with no parameters. 2372 QualType R = Context.getFunctionType( 2373 NewFD->getType()->getAsFunctionType()->getResultType(), 2374 0, 0, true, 0); 2375 NewFD->setType(R); 2376 return NewFD->setInvalidDecl(); 2377 } 2378 } 2379 2380 if (PrevDecl && 2381 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2382 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2383 Redeclaration = true; 2384 Decl *OldDecl = PrevDecl; 2385 2386 // If PrevDecl was an overloaded function, extract the 2387 // FunctionDecl that matched. 2388 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2389 OldDecl = *MatchedDecl; 2390 2391 // NewFD and OldDecl represent declarations that need to be 2392 // merged. 2393 if (MergeFunctionDecl(NewFD, OldDecl)) 2394 return NewFD->setInvalidDecl(); 2395 2396 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2397 } 2398 } 2399 2400 // In C++, check default arguments now that we have merged decls. Unless 2401 // the lexical context is the class, because in this case this is done 2402 // during delayed parsing anyway. 2403 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2404 CheckCXXDefaultArguments(NewFD); 2405} 2406 2407bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2408 // FIXME: Need strict checking. In C89, we need to check for 2409 // any assignment, increment, decrement, function-calls, or 2410 // commas outside of a sizeof. In C99, it's the same list, 2411 // except that the aforementioned are allowed in unevaluated 2412 // expressions. Everything else falls under the 2413 // "may accept other forms of constant expressions" exception. 2414 // (We never end up here for C++, so the constant expression 2415 // rules there don't matter.) 2416 if (Init->isConstantInitializer(Context)) 2417 return false; 2418 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2419 << Init->getSourceRange(); 2420 return true; 2421} 2422 2423void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2424 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2425} 2426 2427/// AddInitializerToDecl - Adds the initializer Init to the 2428/// declaration dcl. If DirectInit is true, this is C++ direct 2429/// initialization rather than copy initialization. 2430void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2431 Decl *RealDecl = dcl.getAs<Decl>(); 2432 // If there is no declaration, there was an error parsing it. Just ignore 2433 // the initializer. 2434 if (RealDecl == 0) 2435 return; 2436 2437 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2438 // With declarators parsed the way they are, the parser cannot 2439 // distinguish between a normal initializer and a pure-specifier. 2440 // Thus this grotesque test. 2441 IntegerLiteral *IL; 2442 Expr *Init = static_cast<Expr *>(init.get()); 2443 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2444 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2445 if (Method->isVirtual()) { 2446 Method->setPure(); 2447 2448 // A class is abstract if at least one function is pure virtual. 2449 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2450 } else if (!Method->isInvalidDecl()) { 2451 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2452 << Method->getDeclName() << Init->getSourceRange(); 2453 Method->setInvalidDecl(); 2454 } 2455 } else { 2456 Diag(Method->getLocation(), diag::err_member_function_initialization) 2457 << Method->getDeclName() << Init->getSourceRange(); 2458 Method->setInvalidDecl(); 2459 } 2460 return; 2461 } 2462 2463 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2464 if (!VDecl) { 2465 if (getLangOptions().CPlusPlus && 2466 RealDecl->getLexicalDeclContext()->isRecord() && 2467 isa<NamedDecl>(RealDecl)) 2468 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2469 << cast<NamedDecl>(RealDecl)->getDeclName(); 2470 else 2471 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2472 RealDecl->setInvalidDecl(); 2473 return; 2474 } 2475 2476 if (!VDecl->getType()->isArrayType() && 2477 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2478 diag::err_typecheck_decl_incomplete_type)) { 2479 RealDecl->setInvalidDecl(); 2480 return; 2481 } 2482 2483 const VarDecl *Def = 0; 2484 if (VDecl->getDefinition(Def)) { 2485 Diag(VDecl->getLocation(), diag::err_redefinition) 2486 << VDecl->getDeclName(); 2487 Diag(Def->getLocation(), diag::note_previous_definition); 2488 VDecl->setInvalidDecl(); 2489 return; 2490 } 2491 2492 // Take ownership of the expression, now that we're sure we have somewhere 2493 // to put it. 2494 Expr *Init = static_cast<Expr *>(init.release()); 2495 assert(Init && "missing initializer"); 2496 2497 // Get the decls type and save a reference for later, since 2498 // CheckInitializerTypes may change it. 2499 QualType DclT = VDecl->getType(), SavT = DclT; 2500 if (VDecl->isBlockVarDecl()) { 2501 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2502 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2503 VDecl->setInvalidDecl(); 2504 } else if (!VDecl->isInvalidDecl()) { 2505 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2506 VDecl->getDeclName(), DirectInit)) 2507 VDecl->setInvalidDecl(); 2508 2509 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2510 // Don't check invalid declarations to avoid emitting useless diagnostics. 2511 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2512 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2513 CheckForConstantInitializer(Init, DclT); 2514 } 2515 } 2516 } else if (VDecl->isStaticDataMember() && 2517 VDecl->getLexicalDeclContext()->isRecord()) { 2518 // This is an in-class initialization for a static data member, e.g., 2519 // 2520 // struct S { 2521 // static const int value = 17; 2522 // }; 2523 2524 // Attach the initializer 2525 VDecl->setInit(Init); 2526 2527 // C++ [class.mem]p4: 2528 // A member-declarator can contain a constant-initializer only 2529 // if it declares a static member (9.4) of const integral or 2530 // const enumeration type, see 9.4.2. 2531 QualType T = VDecl->getType(); 2532 if (!T->isDependentType() && 2533 (!Context.getCanonicalType(T).isConstQualified() || 2534 !T->isIntegralType())) { 2535 Diag(VDecl->getLocation(), diag::err_member_initialization) 2536 << VDecl->getDeclName() << Init->getSourceRange(); 2537 VDecl->setInvalidDecl(); 2538 } else { 2539 // C++ [class.static.data]p4: 2540 // If a static data member is of const integral or const 2541 // enumeration type, its declaration in the class definition 2542 // can specify a constant-initializer which shall be an 2543 // integral constant expression (5.19). 2544 if (!Init->isTypeDependent() && 2545 !Init->getType()->isIntegralType()) { 2546 // We have a non-dependent, non-integral or enumeration type. 2547 Diag(Init->getSourceRange().getBegin(), 2548 diag::err_in_class_initializer_non_integral_type) 2549 << Init->getType() << Init->getSourceRange(); 2550 VDecl->setInvalidDecl(); 2551 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2552 // Check whether the expression is a constant expression. 2553 llvm::APSInt Value; 2554 SourceLocation Loc; 2555 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2556 Diag(Loc, diag::err_in_class_initializer_non_constant) 2557 << Init->getSourceRange(); 2558 VDecl->setInvalidDecl(); 2559 } else if (!VDecl->getType()->isDependentType()) 2560 ImpCastExprToType(Init, VDecl->getType()); 2561 } 2562 } 2563 } else if (VDecl->isFileVarDecl()) { 2564 if (VDecl->getStorageClass() == VarDecl::Extern) 2565 Diag(VDecl->getLocation(), diag::warn_extern_init); 2566 if (!VDecl->isInvalidDecl()) 2567 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2568 VDecl->getDeclName(), DirectInit)) 2569 VDecl->setInvalidDecl(); 2570 2571 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2572 // Don't check invalid declarations to avoid emitting useless diagnostics. 2573 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2574 // C99 6.7.8p4. All file scoped initializers need to be constant. 2575 CheckForConstantInitializer(Init, DclT); 2576 } 2577 } 2578 // If the type changed, it means we had an incomplete type that was 2579 // completed by the initializer. For example: 2580 // int ary[] = { 1, 3, 5 }; 2581 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2582 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2583 VDecl->setType(DclT); 2584 Init->setType(DclT); 2585 } 2586 2587 // Attach the initializer to the decl. 2588 VDecl->setInit(Init); 2589 2590 // If the previous declaration of VDecl was a tentative definition, 2591 // remove it from the set of tentative definitions. 2592 if (VDecl->getPreviousDeclaration() && 2593 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2594 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2595 = TentativeDefinitions.find(VDecl->getDeclName()); 2596 assert(Pos != TentativeDefinitions.end() && 2597 "Unrecorded tentative definition?"); 2598 TentativeDefinitions.erase(Pos); 2599 } 2600 2601 return; 2602} 2603 2604void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2605 Decl *RealDecl = dcl.getAs<Decl>(); 2606 2607 // If there is no declaration, there was an error parsing it. Just ignore it. 2608 if (RealDecl == 0) 2609 return; 2610 2611 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2612 QualType Type = Var->getType(); 2613 2614 // Record tentative definitions. 2615 if (Var->isTentativeDefinition(Context)) 2616 TentativeDefinitions[Var->getDeclName()] = Var; 2617 2618 // C++ [dcl.init.ref]p3: 2619 // The initializer can be omitted for a reference only in a 2620 // parameter declaration (8.3.5), in the declaration of a 2621 // function return type, in the declaration of a class member 2622 // within its class declaration (9.2), and where the extern 2623 // specifier is explicitly used. 2624 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2625 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2626 << Var->getDeclName() 2627 << SourceRange(Var->getLocation(), Var->getLocation()); 2628 Var->setInvalidDecl(); 2629 return; 2630 } 2631 2632 // C++ [dcl.init]p9: 2633 // 2634 // If no initializer is specified for an object, and the object 2635 // is of (possibly cv-qualified) non-POD class type (or array 2636 // thereof), the object shall be default-initialized; if the 2637 // object is of const-qualified type, the underlying class type 2638 // shall have a user-declared default constructor. 2639 if (getLangOptions().CPlusPlus) { 2640 QualType InitType = Type; 2641 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2642 InitType = Array->getElementType(); 2643 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2644 CXXRecordDecl *RD = 2645 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2646 CXXConstructorDecl *Constructor = 0; 2647 if (!RequireCompleteType(Var->getLocation(), InitType, 2648 diag::err_invalid_incomplete_type_use)) 2649 Constructor 2650 = PerformInitializationByConstructor(InitType, 0, 0, 2651 Var->getLocation(), 2652 SourceRange(Var->getLocation(), 2653 Var->getLocation()), 2654 Var->getDeclName(), 2655 IK_Default); 2656 if (!Constructor) 2657 Var->setInvalidDecl(); 2658 else if (!RD->hasTrivialConstructor()) 2659 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2660 } 2661 } 2662 2663#if 0 2664 // FIXME: Temporarily disabled because we are not properly parsing 2665 // linkage specifications on declarations, e.g., 2666 // 2667 // extern "C" const CGPoint CGPointerZero; 2668 // 2669 // C++ [dcl.init]p9: 2670 // 2671 // If no initializer is specified for an object, and the 2672 // object is of (possibly cv-qualified) non-POD class type (or 2673 // array thereof), the object shall be default-initialized; if 2674 // the object is of const-qualified type, the underlying class 2675 // type shall have a user-declared default 2676 // constructor. Otherwise, if no initializer is specified for 2677 // an object, the object and its subobjects, if any, have an 2678 // indeterminate initial value; if the object or any of its 2679 // subobjects are of const-qualified type, the program is 2680 // ill-formed. 2681 // 2682 // This isn't technically an error in C, so we don't diagnose it. 2683 // 2684 // FIXME: Actually perform the POD/user-defined default 2685 // constructor check. 2686 if (getLangOptions().CPlusPlus && 2687 Context.getCanonicalType(Type).isConstQualified() && 2688 !Var->hasExternalStorage()) 2689 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2690 << Var->getName() 2691 << SourceRange(Var->getLocation(), Var->getLocation()); 2692#endif 2693 } 2694} 2695 2696Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2697 unsigned NumDecls) { 2698 llvm::SmallVector<Decl*, 8> Decls; 2699 2700 for (unsigned i = 0; i != NumDecls; ++i) 2701 if (Decl *D = Group[i].getAs<Decl>()) 2702 Decls.push_back(D); 2703 2704 // Perform semantic analysis that depends on having fully processed both 2705 // the declarator and initializer. 2706 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2707 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2708 if (!IDecl) 2709 continue; 2710 QualType T = IDecl->getType(); 2711 2712 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2713 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2714 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2715 if (!IDecl->isInvalidDecl() && 2716 RequireCompleteType(IDecl->getLocation(), T, 2717 diag::err_typecheck_decl_incomplete_type)) 2718 IDecl->setInvalidDecl(); 2719 } 2720 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2721 // object that has file scope without an initializer, and without a 2722 // storage-class specifier or with the storage-class specifier "static", 2723 // constitutes a tentative definition. Note: A tentative definition with 2724 // external linkage is valid (C99 6.2.2p5). 2725 if (IDecl->isTentativeDefinition(Context)) { 2726 QualType CheckType = T; 2727 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2728 2729 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2730 if (ArrayT) { 2731 CheckType = ArrayT->getElementType(); 2732 DiagID = diag::err_illegal_decl_array_incomplete_type; 2733 } 2734 2735 if (IDecl->isInvalidDecl()) { 2736 // Do nothing with invalid declarations 2737 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2738 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2739 // C99 6.9.2p3: If the declaration of an identifier for an object is 2740 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2741 // declared type shall not be an incomplete type. 2742 IDecl->setInvalidDecl(); 2743 } 2744 } 2745 } 2746 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2747 &Decls[0], Decls.size())); 2748} 2749 2750 2751/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2752/// to introduce parameters into function prototype scope. 2753Sema::DeclPtrTy 2754Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2755 const DeclSpec &DS = D.getDeclSpec(); 2756 2757 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2758 VarDecl::StorageClass StorageClass = VarDecl::None; 2759 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2760 StorageClass = VarDecl::Register; 2761 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2762 Diag(DS.getStorageClassSpecLoc(), 2763 diag::err_invalid_storage_class_in_func_decl); 2764 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2765 } 2766 2767 if (D.getDeclSpec().isThreadSpecified()) 2768 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2769 2770 DiagnoseFunctionSpecifiers(D); 2771 2772 // Check that there are no default arguments inside the type of this 2773 // parameter (C++ only). 2774 if (getLangOptions().CPlusPlus) 2775 CheckExtraCXXDefaultArguments(D); 2776 2777 QualType parmDeclType = GetTypeForDeclarator(D, S); 2778 2779 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2780 // Can this happen for params? We already checked that they don't conflict 2781 // among each other. Here they can only shadow globals, which is ok. 2782 IdentifierInfo *II = D.getIdentifier(); 2783 if (II) { 2784 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2785 if (PrevDecl->isTemplateParameter()) { 2786 // Maybe we will complain about the shadowed template parameter. 2787 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2788 // Just pretend that we didn't see the previous declaration. 2789 PrevDecl = 0; 2790 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2791 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2792 2793 // Recover by removing the name 2794 II = 0; 2795 D.SetIdentifier(0, D.getIdentifierLoc()); 2796 } 2797 } 2798 } 2799 2800 // Parameters can not be abstract class types. 2801 // For record types, this is done by the AbstractClassUsageDiagnoser once 2802 // the class has been completely parsed. 2803 if (!CurContext->isRecord() && 2804 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2805 diag::err_abstract_type_in_decl, 2806 AbstractParamType)) 2807 D.setInvalidType(true); 2808 2809 QualType T = adjustParameterType(parmDeclType); 2810 2811 ParmVarDecl *New; 2812 if (T == parmDeclType) // parameter type did not need adjustment 2813 New = ParmVarDecl::Create(Context, CurContext, 2814 D.getIdentifierLoc(), II, 2815 parmDeclType, StorageClass, 2816 0); 2817 else // keep track of both the adjusted and unadjusted types 2818 New = OriginalParmVarDecl::Create(Context, CurContext, 2819 D.getIdentifierLoc(), II, T, 2820 parmDeclType, StorageClass, 0); 2821 2822 if (D.isInvalidType()) 2823 New->setInvalidDecl(); 2824 2825 // Parameter declarators cannot be interface types. All ObjC objects are 2826 // passed by reference. 2827 if (T->isObjCInterfaceType()) { 2828 Diag(D.getIdentifierLoc(), 2829 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2830 New->setInvalidDecl(); 2831 } 2832 2833 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2834 if (D.getCXXScopeSpec().isSet()) { 2835 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2836 << D.getCXXScopeSpec().getRange(); 2837 New->setInvalidDecl(); 2838 } 2839 2840 // Add the parameter declaration into this scope. 2841 S->AddDecl(DeclPtrTy::make(New)); 2842 if (II) 2843 IdResolver.AddDecl(New); 2844 2845 ProcessDeclAttributes(New, D); 2846 return DeclPtrTy::make(New); 2847} 2848 2849void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2850 SourceLocation LocAfterDecls) { 2851 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2852 "Not a function declarator!"); 2853 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2854 2855 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2856 // for a K&R function. 2857 if (!FTI.hasPrototype) { 2858 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2859 --i; 2860 if (FTI.ArgInfo[i].Param == 0) { 2861 std::string Code = " int "; 2862 Code += FTI.ArgInfo[i].Ident->getName(); 2863 Code += ";\n"; 2864 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2865 << FTI.ArgInfo[i].Ident 2866 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2867 2868 // Implicitly declare the argument as type 'int' for lack of a better 2869 // type. 2870 DeclSpec DS; 2871 const char* PrevSpec; // unused 2872 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2873 PrevSpec); 2874 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2875 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2876 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2877 } 2878 } 2879 } 2880} 2881 2882Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2883 Declarator &D) { 2884 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2885 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2886 "Not a function declarator!"); 2887 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2888 2889 if (FTI.hasPrototype) { 2890 // FIXME: Diagnose arguments without names in C. 2891 } 2892 2893 Scope *ParentScope = FnBodyScope->getParent(); 2894 2895 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2896 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2897} 2898 2899Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2900 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2901 2902 CurFunctionNeedsScopeChecking = false; 2903 2904 // See if this is a redefinition. 2905 const FunctionDecl *Definition; 2906 if (FD->getBody(Context, Definition)) { 2907 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2908 Diag(Definition->getLocation(), diag::note_previous_definition); 2909 } 2910 2911 // Builtin functions cannot be defined. 2912 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2913 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2914 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2915 FD->setInvalidDecl(); 2916 } 2917 } 2918 2919 // The return type of a function definition must be complete 2920 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2921 QualType ResultType = FD->getResultType(); 2922 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2923 RequireCompleteType(FD->getLocation(), ResultType, 2924 diag::err_func_def_incomplete_result)) 2925 FD->setInvalidDecl(); 2926 2927 // GNU warning -Wmissing-prototypes: 2928 // Warn if a global function is defined without a previous 2929 // prototype declaration. This warning is issued even if the 2930 // definition itself provides a prototype. The aim is to detect 2931 // global functions that fail to be declared in header files. 2932 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2933 !FD->isMain()) { 2934 bool MissingPrototype = true; 2935 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2936 Prev; Prev = Prev->getPreviousDeclaration()) { 2937 // Ignore any declarations that occur in function or method 2938 // scope, because they aren't visible from the header. 2939 if (Prev->getDeclContext()->isFunctionOrMethod()) 2940 continue; 2941 2942 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2943 break; 2944 } 2945 2946 if (MissingPrototype) 2947 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2948 } 2949 2950 PushDeclContext(FnBodyScope, FD); 2951 2952 // Check the validity of our function parameters 2953 CheckParmsForFunctionDef(FD); 2954 2955 // Introduce our parameters into the function scope 2956 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2957 ParmVarDecl *Param = FD->getParamDecl(p); 2958 Param->setOwningFunction(FD); 2959 2960 // If this has an identifier, add it to the scope stack. 2961 if (Param->getIdentifier()) 2962 PushOnScopeChains(Param, FnBodyScope); 2963 } 2964 2965 // Checking attributes of current function definition 2966 // dllimport attribute. 2967 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2968 // dllimport attribute cannot be applied to definition. 2969 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2970 Diag(FD->getLocation(), 2971 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2972 << "dllimport"; 2973 FD->setInvalidDecl(); 2974 return DeclPtrTy::make(FD); 2975 } else { 2976 // If a symbol previously declared dllimport is later defined, the 2977 // attribute is ignored in subsequent references, and a warning is 2978 // emitted. 2979 Diag(FD->getLocation(), 2980 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2981 << FD->getNameAsCString() << "dllimport"; 2982 } 2983 } 2984 return DeclPtrTy::make(FD); 2985} 2986 2987 2988Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 2989 Decl *dcl = D.getAs<Decl>(); 2990 Stmt *Body = BodyArg.takeAs<Stmt>(); 2991 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2992 FD->setBody(Body); 2993 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2994 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2995 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2996 MD->setBody(Body); 2997 } else { 2998 Body->Destroy(Context); 2999 return DeclPtrTy(); 3000 } 3001 PopDeclContext(); 3002 // Verify and clean out per-function state. 3003 3004 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3005 3006 // Check goto/label use. 3007 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3008 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3009 LabelStmt *L = I->second; 3010 3011 // Verify that we have no forward references left. If so, there was a goto 3012 // or address of a label taken, but no definition of it. Label fwd 3013 // definitions are indicated with a null substmt. 3014 if (L->getSubStmt() != 0) 3015 continue; 3016 3017 // Emit error. 3018 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3019 3020 // At this point, we have gotos that use the bogus label. Stitch it into 3021 // the function body so that they aren't leaked and that the AST is well 3022 // formed. 3023 if (Body == 0) { 3024 // The whole function wasn't parsed correctly, just delete this. 3025 L->Destroy(Context); 3026 continue; 3027 } 3028 3029 // Otherwise, the body is valid: we want to stitch the label decl into the 3030 // function somewhere so that it is properly owned and so that the goto 3031 // has a valid target. Do this by creating a new compound stmt with the 3032 // label in it. 3033 3034 // Give the label a sub-statement. 3035 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3036 3037 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3038 cast<CXXTryStmt>(Body)->getTryBlock() : 3039 cast<CompoundStmt>(Body); 3040 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3041 Elements.push_back(L); 3042 Compound->setStmts(Context, &Elements[0], Elements.size()); 3043 } 3044 FunctionLabelMap.clear(); 3045 3046 if (!Body) return D; 3047 3048 // Verify that that gotos and switch cases don't jump into scopes illegally. 3049 if (CurFunctionNeedsScopeChecking) 3050 DiagnoseInvalidJumps(Body); 3051 3052 return D; 3053} 3054 3055/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3056/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3057NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3058 IdentifierInfo &II, Scope *S) { 3059 // Before we produce a declaration for an implicitly defined 3060 // function, see whether there was a locally-scoped declaration of 3061 // this name as a function or variable. If so, use that 3062 // (non-visible) declaration, and complain about it. 3063 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3064 = LocallyScopedExternalDecls.find(&II); 3065 if (Pos != LocallyScopedExternalDecls.end()) { 3066 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3067 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3068 return Pos->second; 3069 } 3070 3071 // Extension in C99. Legal in C90, but warn about it. 3072 if (getLangOptions().C99) 3073 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3074 else 3075 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3076 3077 // FIXME: handle stuff like: 3078 // void foo() { extern float X(); } 3079 // void bar() { X(); } <-- implicit decl for X in another scope. 3080 3081 // Set a Declarator for the implicit definition: int foo(); 3082 const char *Dummy; 3083 DeclSpec DS; 3084 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3085 Error = Error; // Silence warning. 3086 assert(!Error && "Error setting up implicit decl!"); 3087 Declarator D(DS, Declarator::BlockContext); 3088 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3089 0, 0, 0, Loc, D), 3090 SourceLocation()); 3091 D.SetIdentifier(&II, Loc); 3092 3093 // Insert this function into translation-unit scope. 3094 3095 DeclContext *PrevDC = CurContext; 3096 CurContext = Context.getTranslationUnitDecl(); 3097 3098 FunctionDecl *FD = 3099 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3100 FD->setImplicit(); 3101 3102 CurContext = PrevDC; 3103 3104 AddKnownFunctionAttributes(FD); 3105 3106 return FD; 3107} 3108 3109/// \brief Adds any function attributes that we know a priori based on 3110/// the declaration of this function. 3111/// 3112/// These attributes can apply both to implicitly-declared builtins 3113/// (like __builtin___printf_chk) or to library-declared functions 3114/// like NSLog or printf. 3115void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3116 if (FD->isInvalidDecl()) 3117 return; 3118 3119 // If this is a built-in function, map its builtin attributes to 3120 // actual attributes. 3121 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3122 // Handle printf-formatting attributes. 3123 unsigned FormatIdx; 3124 bool HasVAListArg; 3125 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3126 if (!FD->getAttr<FormatAttr>()) 3127 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3128 FormatIdx + 2)); 3129 } 3130 3131 // Mark const if we don't care about errno and that is the only 3132 // thing preventing the function from being const. This allows 3133 // IRgen to use LLVM intrinsics for such functions. 3134 if (!getLangOptions().MathErrno && 3135 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3136 if (!FD->getAttr<ConstAttr>()) 3137 FD->addAttr(::new (Context) ConstAttr()); 3138 } 3139 } 3140 3141 IdentifierInfo *Name = FD->getIdentifier(); 3142 if (!Name) 3143 return; 3144 if ((!getLangOptions().CPlusPlus && 3145 FD->getDeclContext()->isTranslationUnit()) || 3146 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3147 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3148 LinkageSpecDecl::lang_c)) { 3149 // Okay: this could be a libc/libm/Objective-C function we know 3150 // about. 3151 } else 3152 return; 3153 3154 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3155 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3156 // FIXME: We known better than our headers. 3157 const_cast<FormatAttr *>(Format)->setType("printf"); 3158 } else 3159 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3160 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3161 if (!FD->getAttr<FormatAttr>()) 3162 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3163 } 3164} 3165 3166TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3167 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3168 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3169 3170 // Scope manipulation handled by caller. 3171 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3172 D.getIdentifierLoc(), 3173 D.getIdentifier(), 3174 T); 3175 3176 if (TagType *TT = dyn_cast<TagType>(T)) { 3177 TagDecl *TD = TT->getDecl(); 3178 3179 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3180 // keep track of the TypedefDecl. 3181 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3182 TD->setTypedefForAnonDecl(NewTD); 3183 } 3184 3185 if (D.isInvalidType()) 3186 NewTD->setInvalidDecl(); 3187 return NewTD; 3188} 3189 3190/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3191/// former case, Name will be non-null. In the later case, Name will be null. 3192/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3193/// reference/declaration/definition of a tag. 3194Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3195 SourceLocation KWLoc, const CXXScopeSpec &SS, 3196 IdentifierInfo *Name, SourceLocation NameLoc, 3197 AttributeList *Attr, AccessSpecifier AS) { 3198 // If this is not a definition, it must have a name. 3199 assert((Name != 0 || TK == TK_Definition) && 3200 "Nameless record must be a definition!"); 3201 3202 TagDecl::TagKind Kind; 3203 switch (TagSpec) { 3204 default: assert(0 && "Unknown tag type!"); 3205 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3206 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3207 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3208 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3209 } 3210 3211 DeclContext *SearchDC = CurContext; 3212 DeclContext *DC = CurContext; 3213 NamedDecl *PrevDecl = 0; 3214 3215 bool Invalid = false; 3216 3217 if (Name && SS.isNotEmpty()) { 3218 // We have a nested-name tag ('struct foo::bar'). 3219 3220 // Check for invalid 'foo::'. 3221 if (SS.isInvalid()) { 3222 Name = 0; 3223 goto CreateNewDecl; 3224 } 3225 3226 // FIXME: RequireCompleteDeclContext(SS)? 3227 DC = computeDeclContext(SS); 3228 SearchDC = DC; 3229 // Look-up name inside 'foo::'. 3230 PrevDecl = dyn_cast_or_null<TagDecl>( 3231 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3232 3233 // A tag 'foo::bar' must already exist. 3234 if (PrevDecl == 0) { 3235 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3236 Name = 0; 3237 goto CreateNewDecl; 3238 } 3239 } else if (Name) { 3240 // If this is a named struct, check to see if there was a previous forward 3241 // declaration or definition. 3242 // FIXME: We're looking into outer scopes here, even when we 3243 // shouldn't be. Doing so can result in ambiguities that we 3244 // shouldn't be diagnosing. 3245 LookupResult R = LookupName(S, Name, LookupTagName, 3246 /*RedeclarationOnly=*/(TK != TK_Reference)); 3247 if (R.isAmbiguous()) { 3248 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3249 // FIXME: This is not best way to recover from case like: 3250 // 3251 // struct S s; 3252 // 3253 // causes needless "incomplete type" error later. 3254 Name = 0; 3255 PrevDecl = 0; 3256 Invalid = true; 3257 } 3258 else 3259 PrevDecl = R; 3260 3261 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3262 // FIXME: This makes sure that we ignore the contexts associated 3263 // with C structs, unions, and enums when looking for a matching 3264 // tag declaration or definition. See the similar lookup tweak 3265 // in Sema::LookupName; is there a better way to deal with this? 3266 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3267 SearchDC = SearchDC->getParent(); 3268 } 3269 } 3270 3271 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3272 // Maybe we will complain about the shadowed template parameter. 3273 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3274 // Just pretend that we didn't see the previous declaration. 3275 PrevDecl = 0; 3276 } 3277 3278 if (PrevDecl) { 3279 // Check whether the previous declaration is usable. 3280 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3281 3282 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3283 // If this is a use of a previous tag, or if the tag is already declared 3284 // in the same scope (so that the definition/declaration completes or 3285 // rementions the tag), reuse the decl. 3286 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3287 // Make sure that this wasn't declared as an enum and now used as a 3288 // struct or something similar. 3289 if (PrevTagDecl->getTagKind() != Kind) { 3290 bool SafeToContinue 3291 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3292 Kind != TagDecl::TK_enum); 3293 if (SafeToContinue) 3294 Diag(KWLoc, diag::err_use_with_wrong_tag) 3295 << Name 3296 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3297 PrevTagDecl->getKindName()); 3298 else 3299 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3300 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3301 3302 if (SafeToContinue) 3303 Kind = PrevTagDecl->getTagKind(); 3304 else { 3305 // Recover by making this an anonymous redefinition. 3306 Name = 0; 3307 PrevDecl = 0; 3308 Invalid = true; 3309 } 3310 } 3311 3312 if (!Invalid) { 3313 // If this is a use, just return the declaration we found. 3314 3315 // FIXME: In the future, return a variant or some other clue 3316 // for the consumer of this Decl to know it doesn't own it. 3317 // For our current ASTs this shouldn't be a problem, but will 3318 // need to be changed with DeclGroups. 3319 if (TK == TK_Reference) 3320 return DeclPtrTy::make(PrevDecl); 3321 3322 // Diagnose attempts to redefine a tag. 3323 if (TK == TK_Definition) { 3324 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3325 Diag(NameLoc, diag::err_redefinition) << Name; 3326 Diag(Def->getLocation(), diag::note_previous_definition); 3327 // If this is a redefinition, recover by making this 3328 // struct be anonymous, which will make any later 3329 // references get the previous definition. 3330 Name = 0; 3331 PrevDecl = 0; 3332 Invalid = true; 3333 } else { 3334 // If the type is currently being defined, complain 3335 // about a nested redefinition. 3336 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3337 if (Tag->isBeingDefined()) { 3338 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3339 Diag(PrevTagDecl->getLocation(), 3340 diag::note_previous_definition); 3341 Name = 0; 3342 PrevDecl = 0; 3343 Invalid = true; 3344 } 3345 } 3346 3347 // Okay, this is definition of a previously declared or referenced 3348 // tag PrevDecl. We're going to create a new Decl for it. 3349 } 3350 } 3351 // If we get here we have (another) forward declaration or we 3352 // have a definition. Just create a new decl. 3353 } else { 3354 // If we get here, this is a definition of a new tag type in a nested 3355 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3356 // new decl/type. We set PrevDecl to NULL so that the entities 3357 // have distinct types. 3358 PrevDecl = 0; 3359 } 3360 // If we get here, we're going to create a new Decl. If PrevDecl 3361 // is non-NULL, it's a definition of the tag declared by 3362 // PrevDecl. If it's NULL, we have a new definition. 3363 } else { 3364 // PrevDecl is a namespace, template, or anything else 3365 // that lives in the IDNS_Tag identifier namespace. 3366 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3367 // The tag name clashes with a namespace name, issue an error and 3368 // recover by making this tag be anonymous. 3369 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3370 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3371 Name = 0; 3372 PrevDecl = 0; 3373 Invalid = true; 3374 } else { 3375 // The existing declaration isn't relevant to us; we're in a 3376 // new scope, so clear out the previous declaration. 3377 PrevDecl = 0; 3378 } 3379 } 3380 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3381 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3382 // C.scope.pdecl]p5: 3383 // -- for an elaborated-type-specifier of the form 3384 // 3385 // class-key identifier 3386 // 3387 // if the elaborated-type-specifier is used in the 3388 // decl-specifier-seq or parameter-declaration-clause of a 3389 // function defined in namespace scope, the identifier is 3390 // declared as a class-name in the namespace that contains 3391 // the declaration; otherwise, except as a friend 3392 // declaration, the identifier is declared in the smallest 3393 // non-class, non-function-prototype scope that contains the 3394 // declaration. 3395 // 3396 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3397 // C structs and unions. 3398 // 3399 // GNU C also supports this behavior as part of its incomplete 3400 // enum types extension, while GNU C++ does not. 3401 // 3402 // Find the context where we'll be declaring the tag. 3403 // FIXME: We would like to maintain the current DeclContext as the 3404 // lexical context, 3405 while (SearchDC->isRecord()) 3406 SearchDC = SearchDC->getParent(); 3407 3408 // Find the scope where we'll be declaring the tag. 3409 while (S->isClassScope() || 3410 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3411 ((S->getFlags() & Scope::DeclScope) == 0) || 3412 (S->getEntity() && 3413 ((DeclContext *)S->getEntity())->isTransparentContext())) 3414 S = S->getParent(); 3415 } 3416 3417CreateNewDecl: 3418 3419 // If there is an identifier, use the location of the identifier as the 3420 // location of the decl, otherwise use the location of the struct/union 3421 // keyword. 3422 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3423 3424 // Otherwise, create a new declaration. If there is a previous 3425 // declaration of the same entity, the two will be linked via 3426 // PrevDecl. 3427 TagDecl *New; 3428 3429 if (Kind == TagDecl::TK_enum) { 3430 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3431 // enum X { A, B, C } D; D should chain to X. 3432 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3433 cast_or_null<EnumDecl>(PrevDecl)); 3434 // If this is an undefined enum, warn. 3435 if (TK != TK_Definition && !Invalid) { 3436 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3437 : diag::ext_forward_ref_enum; 3438 Diag(Loc, DK); 3439 } 3440 } else { 3441 // struct/union/class 3442 3443 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3444 // struct X { int A; } D; D should chain to X. 3445 if (getLangOptions().CPlusPlus) 3446 // FIXME: Look for a way to use RecordDecl for simple structs. 3447 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3448 cast_or_null<CXXRecordDecl>(PrevDecl)); 3449 else 3450 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3451 cast_or_null<RecordDecl>(PrevDecl)); 3452 } 3453 3454 if (Kind != TagDecl::TK_enum) { 3455 // Handle #pragma pack: if the #pragma pack stack has non-default 3456 // alignment, make up a packed attribute for this decl. These 3457 // attributes are checked when the ASTContext lays out the 3458 // structure. 3459 // 3460 // It is important for implementing the correct semantics that this 3461 // happen here (in act on tag decl). The #pragma pack stack is 3462 // maintained as a result of parser callbacks which can occur at 3463 // many points during the parsing of a struct declaration (because 3464 // the #pragma tokens are effectively skipped over during the 3465 // parsing of the struct). 3466 if (unsigned Alignment = getPragmaPackAlignment()) 3467 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3468 } 3469 3470 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3471 // C++ [dcl.typedef]p3: 3472 // [...] Similarly, in a given scope, a class or enumeration 3473 // shall not be declared with the same name as a typedef-name 3474 // that is declared in that scope and refers to a type other 3475 // than the class or enumeration itself. 3476 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3477 TypedefDecl *PrevTypedef = 0; 3478 if (Lookup.getKind() == LookupResult::Found) 3479 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3480 3481 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3482 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3483 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3484 Diag(Loc, diag::err_tag_definition_of_typedef) 3485 << Context.getTypeDeclType(New) 3486 << PrevTypedef->getUnderlyingType(); 3487 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3488 Invalid = true; 3489 } 3490 } 3491 3492 if (Invalid) 3493 New->setInvalidDecl(); 3494 3495 if (Attr) 3496 ProcessDeclAttributeList(New, Attr); 3497 3498 // If we're declaring or defining a tag in function prototype scope 3499 // in C, note that this type can only be used within the function. 3500 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3501 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3502 3503 // Set the lexical context. If the tag has a C++ scope specifier, the 3504 // lexical context will be different from the semantic context. 3505 New->setLexicalDeclContext(CurContext); 3506 3507 // Set the access specifier. 3508 SetMemberAccessSpecifier(New, PrevDecl, AS); 3509 3510 if (TK == TK_Definition) 3511 New->startDefinition(); 3512 3513 // If this has an identifier, add it to the scope stack. 3514 if (Name) { 3515 S = getNonFieldDeclScope(S); 3516 PushOnScopeChains(New, S); 3517 } else { 3518 CurContext->addDecl(Context, New); 3519 } 3520 3521 return DeclPtrTy::make(New); 3522} 3523 3524void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3525 AdjustDeclIfTemplate(TagD); 3526 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3527 3528 // Enter the tag context. 3529 PushDeclContext(S, Tag); 3530 3531 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3532 FieldCollector->StartClass(); 3533 3534 if (Record->getIdentifier()) { 3535 // C++ [class]p2: 3536 // [...] The class-name is also inserted into the scope of the 3537 // class itself; this is known as the injected-class-name. For 3538 // purposes of access checking, the injected-class-name is treated 3539 // as if it were a public member name. 3540 CXXRecordDecl *InjectedClassName 3541 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3542 CurContext, Record->getLocation(), 3543 Record->getIdentifier(), Record); 3544 InjectedClassName->setImplicit(); 3545 InjectedClassName->setAccess(AS_public); 3546 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3547 InjectedClassName->setDescribedClassTemplate(Template); 3548 PushOnScopeChains(InjectedClassName, S); 3549 assert(InjectedClassName->isInjectedClassName() && 3550 "Broken injected-class-name"); 3551 } 3552 } 3553} 3554 3555void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3556 AdjustDeclIfTemplate(TagD); 3557 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3558 3559 if (isa<CXXRecordDecl>(Tag)) 3560 FieldCollector->FinishClass(); 3561 3562 // Exit this scope of this tag's definition. 3563 PopDeclContext(); 3564 3565 // Notify the consumer that we've defined a tag. 3566 Consumer.HandleTagDeclDefinition(Tag); 3567} 3568 3569// Note that FieldName may be null for anonymous bitfields. 3570bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3571 QualType FieldTy, const Expr *BitWidth) { 3572 3573 // C99 6.7.2.1p4 - verify the field type. 3574 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3575 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3576 // Handle incomplete types with specific error. 3577 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3578 return true; 3579 if (FieldName) 3580 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3581 << FieldName << FieldTy << BitWidth->getSourceRange(); 3582 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3583 << FieldTy << BitWidth->getSourceRange(); 3584 } 3585 3586 // If the bit-width is type- or value-dependent, don't try to check 3587 // it now. 3588 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3589 return false; 3590 3591 llvm::APSInt Value; 3592 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3593 return true; 3594 3595 // Zero-width bitfield is ok for anonymous field. 3596 if (Value == 0 && FieldName) 3597 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3598 3599 if (Value.isSigned() && Value.isNegative()) { 3600 if (FieldName) 3601 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3602 << FieldName << Value.toString(10); 3603 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3604 << Value.toString(10); 3605 } 3606 3607 if (!FieldTy->isDependentType()) { 3608 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3609 if (Value.getZExtValue() > TypeSize) { 3610 if (FieldName) 3611 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3612 << FieldName << (unsigned)TypeSize; 3613 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3614 << (unsigned)TypeSize; 3615 } 3616 } 3617 3618 return false; 3619} 3620 3621/// ActOnField - Each field of a struct/union/class is passed into this in order 3622/// to create a FieldDecl object for it. 3623Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3624 SourceLocation DeclStart, 3625 Declarator &D, ExprTy *BitfieldWidth) { 3626 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3627 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3628 AS_public); 3629 return DeclPtrTy::make(Res); 3630} 3631 3632/// HandleField - Analyze a field of a C struct or a C++ data member. 3633/// 3634FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3635 SourceLocation DeclStart, 3636 Declarator &D, Expr *BitWidth, 3637 AccessSpecifier AS) { 3638 IdentifierInfo *II = D.getIdentifier(); 3639 SourceLocation Loc = DeclStart; 3640 if (II) Loc = D.getIdentifierLoc(); 3641 3642 QualType T = GetTypeForDeclarator(D, S); 3643 if (getLangOptions().CPlusPlus) 3644 CheckExtraCXXDefaultArguments(D); 3645 3646 DiagnoseFunctionSpecifiers(D); 3647 3648 if (D.getDeclSpec().isThreadSpecified()) 3649 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3650 3651 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3652 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3653 PrevDecl = 0; 3654 3655 FieldDecl *NewFD 3656 = CheckFieldDecl(II, T, Record, Loc, 3657 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3658 BitWidth, AS, PrevDecl, &D); 3659 if (NewFD->isInvalidDecl() && PrevDecl) { 3660 // Don't introduce NewFD into scope; there's already something 3661 // with the same name in the same scope. 3662 } else if (II) { 3663 PushOnScopeChains(NewFD, S); 3664 } else 3665 Record->addDecl(Context, NewFD); 3666 3667 return NewFD; 3668} 3669 3670/// \brief Build a new FieldDecl and check its well-formedness. 3671/// 3672/// This routine builds a new FieldDecl given the fields name, type, 3673/// record, etc. \p PrevDecl should refer to any previous declaration 3674/// with the same name and in the same scope as the field to be 3675/// created. 3676/// 3677/// \returns a new FieldDecl. 3678/// 3679/// \todo The Declarator argument is a hack. It will be removed once 3680FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3681 RecordDecl *Record, SourceLocation Loc, 3682 bool Mutable, Expr *BitWidth, 3683 AccessSpecifier AS, NamedDecl *PrevDecl, 3684 Declarator *D) { 3685 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3686 bool InvalidDecl = false; 3687 if (D) InvalidDecl = D->isInvalidType(); 3688 3689 // If we receive a broken type, recover by assuming 'int' and 3690 // marking this declaration as invalid. 3691 if (T.isNull()) { 3692 InvalidDecl = true; 3693 T = Context.IntTy; 3694 } 3695 3696 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3697 // than a variably modified type. 3698 if (T->isVariablyModifiedType()) { 3699 bool SizeIsNegative; 3700 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3701 SizeIsNegative); 3702 if (!FixedTy.isNull()) { 3703 Diag(Loc, diag::warn_illegal_constant_array_size); 3704 T = FixedTy; 3705 } else { 3706 if (SizeIsNegative) 3707 Diag(Loc, diag::err_typecheck_negative_array_size); 3708 else 3709 Diag(Loc, diag::err_typecheck_field_variable_size); 3710 T = Context.IntTy; 3711 InvalidDecl = true; 3712 } 3713 } 3714 3715 // Fields can not have abstract class types 3716 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3717 AbstractFieldType)) 3718 InvalidDecl = true; 3719 3720 // If this is declared as a bit-field, check the bit-field. 3721 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3722 InvalidDecl = true; 3723 DeleteExpr(BitWidth); 3724 BitWidth = 0; 3725 } 3726 3727 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3728 Mutable); 3729 if (InvalidDecl) 3730 NewFD->setInvalidDecl(); 3731 3732 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3733 Diag(Loc, diag::err_duplicate_member) << II; 3734 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3735 NewFD->setInvalidDecl(); 3736 Record->setInvalidDecl(); 3737 } 3738 3739 if (getLangOptions().CPlusPlus && !T->isPODType()) 3740 cast<CXXRecordDecl>(Record)->setPOD(false); 3741 3742 // FIXME: We need to pass in the attributes given an AST 3743 // representation, not a parser representation. 3744 if (D) 3745 ProcessDeclAttributes(NewFD, *D); 3746 3747 if (T.isObjCGCWeak()) 3748 Diag(Loc, diag::warn_attribute_weak_on_field); 3749 3750 NewFD->setAccess(AS); 3751 3752 // C++ [dcl.init.aggr]p1: 3753 // An aggregate is an array or a class (clause 9) with [...] no 3754 // private or protected non-static data members (clause 11). 3755 // A POD must be an aggregate. 3756 if (getLangOptions().CPlusPlus && 3757 (AS == AS_private || AS == AS_protected)) { 3758 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3759 CXXRecord->setAggregate(false); 3760 CXXRecord->setPOD(false); 3761 } 3762 3763 return NewFD; 3764} 3765 3766/// TranslateIvarVisibility - Translate visibility from a token ID to an 3767/// AST enum value. 3768static ObjCIvarDecl::AccessControl 3769TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3770 switch (ivarVisibility) { 3771 default: assert(0 && "Unknown visitibility kind"); 3772 case tok::objc_private: return ObjCIvarDecl::Private; 3773 case tok::objc_public: return ObjCIvarDecl::Public; 3774 case tok::objc_protected: return ObjCIvarDecl::Protected; 3775 case tok::objc_package: return ObjCIvarDecl::Package; 3776 } 3777} 3778 3779/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3780/// in order to create an IvarDecl object for it. 3781Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3782 SourceLocation DeclStart, 3783 Declarator &D, ExprTy *BitfieldWidth, 3784 tok::ObjCKeywordKind Visibility) { 3785 3786 IdentifierInfo *II = D.getIdentifier(); 3787 Expr *BitWidth = (Expr*)BitfieldWidth; 3788 SourceLocation Loc = DeclStart; 3789 if (II) Loc = D.getIdentifierLoc(); 3790 3791 // FIXME: Unnamed fields can be handled in various different ways, for 3792 // example, unnamed unions inject all members into the struct namespace! 3793 3794 QualType T = GetTypeForDeclarator(D, S); 3795 3796 if (BitWidth) { 3797 // 6.7.2.1p3, 6.7.2.1p4 3798 if (VerifyBitField(Loc, II, T, BitWidth)) { 3799 D.setInvalidType(); 3800 DeleteExpr(BitWidth); 3801 BitWidth = 0; 3802 } 3803 } else { 3804 // Not a bitfield. 3805 3806 // validate II. 3807 3808 } 3809 3810 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3811 // than a variably modified type. 3812 if (T->isVariablyModifiedType()) { 3813 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3814 D.setInvalidType(); 3815 } 3816 3817 // Get the visibility (access control) for this ivar. 3818 ObjCIvarDecl::AccessControl ac = 3819 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3820 : ObjCIvarDecl::None; 3821 3822 // Construct the decl. 3823 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3824 (Expr *)BitfieldWidth); 3825 3826 if (II) { 3827 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3828 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3829 && !isa<TagDecl>(PrevDecl)) { 3830 Diag(Loc, diag::err_duplicate_member) << II; 3831 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3832 NewID->setInvalidDecl(); 3833 } 3834 } 3835 3836 // Process attributes attached to the ivar. 3837 ProcessDeclAttributes(NewID, D); 3838 3839 if (D.isInvalidType()) 3840 NewID->setInvalidDecl(); 3841 3842 if (II) { 3843 // FIXME: When interfaces are DeclContexts, we'll need to add 3844 // these to the interface. 3845 S->AddDecl(DeclPtrTy::make(NewID)); 3846 IdResolver.AddDecl(NewID); 3847 } 3848 3849 return DeclPtrTy::make(NewID); 3850} 3851 3852void Sema::ActOnFields(Scope* S, 3853 SourceLocation RecLoc, DeclPtrTy RecDecl, 3854 DeclPtrTy *Fields, unsigned NumFields, 3855 SourceLocation LBrac, SourceLocation RBrac, 3856 AttributeList *Attr) { 3857 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3858 assert(EnclosingDecl && "missing record or interface decl"); 3859 3860 // If the decl this is being inserted into is invalid, then it may be a 3861 // redeclaration or some other bogus case. Don't try to add fields to it. 3862 if (EnclosingDecl->isInvalidDecl()) { 3863 // FIXME: Deallocate fields? 3864 return; 3865 } 3866 3867 3868 // Verify that all the fields are okay. 3869 unsigned NumNamedMembers = 0; 3870 llvm::SmallVector<FieldDecl*, 32> RecFields; 3871 3872 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3873 for (unsigned i = 0; i != NumFields; ++i) { 3874 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3875 3876 // Get the type for the field. 3877 Type *FDTy = FD->getType().getTypePtr(); 3878 3879 if (!FD->isAnonymousStructOrUnion()) { 3880 // Remember all fields written by the user. 3881 RecFields.push_back(FD); 3882 } 3883 3884 // If the field is already invalid for some reason, don't emit more 3885 // diagnostics about it. 3886 if (FD->isInvalidDecl()) 3887 continue; 3888 3889 // C99 6.7.2.1p2: 3890 // A structure or union shall not contain a member with 3891 // incomplete or function type (hence, a structure shall not 3892 // contain an instance of itself, but may contain a pointer to 3893 // an instance of itself), except that the last member of a 3894 // structure with more than one named member may have incomplete 3895 // array type; such a structure (and any union containing, 3896 // possibly recursively, a member that is such a structure) 3897 // shall not be a member of a structure or an element of an 3898 // array. 3899 if (FDTy->isFunctionType()) { 3900 // Field declared as a function. 3901 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3902 << FD->getDeclName(); 3903 FD->setInvalidDecl(); 3904 EnclosingDecl->setInvalidDecl(); 3905 continue; 3906 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3907 Record && Record->isStruct()) { 3908 // Flexible array member. 3909 if (NumNamedMembers < 1) { 3910 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3911 << FD->getDeclName(); 3912 FD->setInvalidDecl(); 3913 EnclosingDecl->setInvalidDecl(); 3914 continue; 3915 } 3916 // Okay, we have a legal flexible array member at the end of the struct. 3917 if (Record) 3918 Record->setHasFlexibleArrayMember(true); 3919 } else if (!FDTy->isDependentType() && 3920 RequireCompleteType(FD->getLocation(), FD->getType(), 3921 diag::err_field_incomplete)) { 3922 // Incomplete type 3923 FD->setInvalidDecl(); 3924 EnclosingDecl->setInvalidDecl(); 3925 continue; 3926 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3927 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3928 // If this is a member of a union, then entire union becomes "flexible". 3929 if (Record && Record->isUnion()) { 3930 Record->setHasFlexibleArrayMember(true); 3931 } else { 3932 // If this is a struct/class and this is not the last element, reject 3933 // it. Note that GCC supports variable sized arrays in the middle of 3934 // structures. 3935 if (i != NumFields-1) 3936 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3937 << FD->getDeclName() << FD->getType(); 3938 else { 3939 // We support flexible arrays at the end of structs in 3940 // other structs as an extension. 3941 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3942 << FD->getDeclName(); 3943 if (Record) 3944 Record->setHasFlexibleArrayMember(true); 3945 } 3946 } 3947 } 3948 } else if (FDTy->isObjCInterfaceType()) { 3949 /// A field cannot be an Objective-c object 3950 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3951 FD->setInvalidDecl(); 3952 EnclosingDecl->setInvalidDecl(); 3953 continue; 3954 } 3955 // Keep track of the number of named members. 3956 if (FD->getIdentifier()) 3957 ++NumNamedMembers; 3958 } 3959 3960 // Okay, we successfully defined 'Record'. 3961 if (Record) { 3962 Record->completeDefinition(Context); 3963 } else { 3964 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3965 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3966 ID->setIVarList(ClsFields, RecFields.size(), Context); 3967 ID->setLocEnd(RBrac); 3968 3969 // Must enforce the rule that ivars in the base classes may not be 3970 // duplicates. 3971 if (ID->getSuperClass()) { 3972 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3973 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3974 ObjCIvarDecl* Ivar = (*IVI); 3975 IdentifierInfo *II = Ivar->getIdentifier(); 3976 ObjCIvarDecl* prevIvar = 3977 ID->getSuperClass()->lookupInstanceVariable(Context, II); 3978 if (prevIvar) { 3979 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3980 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3981 } 3982 } 3983 } 3984 } else if (ObjCImplementationDecl *IMPDecl = 3985 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3986 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3987 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) { 3988 // FIXME: Set the DeclContext correctly when we build the 3989 // declarations. 3990 ClsFields[I]->setLexicalDeclContext(IMPDecl); 3991 IMPDecl->addDecl(Context, ClsFields[I]); 3992 } 3993 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3994 } 3995 } 3996 3997 if (Attr) 3998 ProcessDeclAttributeList(Record, Attr); 3999} 4000 4001EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4002 EnumConstantDecl *LastEnumConst, 4003 SourceLocation IdLoc, 4004 IdentifierInfo *Id, 4005 ExprArg val) { 4006 Expr *Val = (Expr *)val.get(); 4007 4008 llvm::APSInt EnumVal(32); 4009 QualType EltTy; 4010 if (Val && !Val->isTypeDependent()) { 4011 // Make sure to promote the operand type to int. 4012 UsualUnaryConversions(Val); 4013 if (Val != val.get()) { 4014 val.release(); 4015 val = Val; 4016 } 4017 4018 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4019 SourceLocation ExpLoc; 4020 if (!Val->isValueDependent() && 4021 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4022 Val = 0; 4023 } else { 4024 EltTy = Val->getType(); 4025 } 4026 } 4027 4028 if (!Val) { 4029 if (LastEnumConst) { 4030 // Assign the last value + 1. 4031 EnumVal = LastEnumConst->getInitVal(); 4032 ++EnumVal; 4033 4034 // Check for overflow on increment. 4035 if (EnumVal < LastEnumConst->getInitVal()) 4036 Diag(IdLoc, diag::warn_enum_value_overflow); 4037 4038 EltTy = LastEnumConst->getType(); 4039 } else { 4040 // First value, set to zero. 4041 EltTy = Context.IntTy; 4042 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4043 } 4044 } 4045 4046 val.release(); 4047 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4048 Val, EnumVal); 4049} 4050 4051 4052Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4053 DeclPtrTy lastEnumConst, 4054 SourceLocation IdLoc, 4055 IdentifierInfo *Id, 4056 SourceLocation EqualLoc, ExprTy *val) { 4057 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4058 EnumConstantDecl *LastEnumConst = 4059 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4060 Expr *Val = static_cast<Expr*>(val); 4061 4062 // The scope passed in may not be a decl scope. Zip up the scope tree until 4063 // we find one that is. 4064 S = getNonFieldDeclScope(S); 4065 4066 // Verify that there isn't already something declared with this name in this 4067 // scope. 4068 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4069 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4070 // Maybe we will complain about the shadowed template parameter. 4071 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4072 // Just pretend that we didn't see the previous declaration. 4073 PrevDecl = 0; 4074 } 4075 4076 if (PrevDecl) { 4077 // When in C++, we may get a TagDecl with the same name; in this case the 4078 // enum constant will 'hide' the tag. 4079 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4080 "Received TagDecl when not in C++!"); 4081 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4082 if (isa<EnumConstantDecl>(PrevDecl)) 4083 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4084 else 4085 Diag(IdLoc, diag::err_redefinition) << Id; 4086 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4087 if (Val) Val->Destroy(Context); 4088 return DeclPtrTy(); 4089 } 4090 } 4091 4092 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4093 IdLoc, Id, Owned(Val)); 4094 4095 // Register this decl in the current scope stack. 4096 if (New) 4097 PushOnScopeChains(New, S); 4098 4099 return DeclPtrTy::make(New); 4100} 4101 4102// FIXME: For consistency with ActOnFields(), we should have the parser 4103// pass in the source location for the left/right braces. 4104void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4105 DeclPtrTy *Elements, unsigned NumElements) { 4106 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4107 QualType EnumType = Context.getTypeDeclType(Enum); 4108 4109 // TODO: If the result value doesn't fit in an int, it must be a long or long 4110 // long value. ISO C does not support this, but GCC does as an extension, 4111 // emit a warning. 4112 unsigned IntWidth = Context.Target.getIntWidth(); 4113 4114 // Verify that all the values are okay, compute the size of the values, and 4115 // reverse the list. 4116 unsigned NumNegativeBits = 0; 4117 unsigned NumPositiveBits = 0; 4118 4119 // Keep track of whether all elements have type int. 4120 bool AllElementsInt = true; 4121 4122 for (unsigned i = 0; i != NumElements; ++i) { 4123 EnumConstantDecl *ECD = 4124 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4125 if (!ECD) continue; // Already issued a diagnostic. 4126 4127 // If the enum value doesn't fit in an int, emit an extension warning. 4128 const llvm::APSInt &InitVal = ECD->getInitVal(); 4129 assert(InitVal.getBitWidth() >= IntWidth && 4130 "Should have promoted value to int"); 4131 if (InitVal.getBitWidth() > IntWidth) { 4132 llvm::APSInt V(InitVal); 4133 V.trunc(IntWidth); 4134 V.extend(InitVal.getBitWidth()); 4135 if (V != InitVal) 4136 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4137 << InitVal.toString(10); 4138 } 4139 4140 // Keep track of the size of positive and negative values. 4141 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4142 NumPositiveBits = std::max(NumPositiveBits, 4143 (unsigned)InitVal.getActiveBits()); 4144 else 4145 NumNegativeBits = std::max(NumNegativeBits, 4146 (unsigned)InitVal.getMinSignedBits()); 4147 4148 // Keep track of whether every enum element has type int (very commmon). 4149 if (AllElementsInt) 4150 AllElementsInt = ECD->getType() == Context.IntTy; 4151 } 4152 4153 // Figure out the type that should be used for this enum. 4154 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4155 QualType BestType; 4156 unsigned BestWidth; 4157 4158 if (NumNegativeBits) { 4159 // If there is a negative value, figure out the smallest integer type (of 4160 // int/long/longlong) that fits. 4161 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4162 BestType = Context.IntTy; 4163 BestWidth = IntWidth; 4164 } else { 4165 BestWidth = Context.Target.getLongWidth(); 4166 4167 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4168 BestType = Context.LongTy; 4169 else { 4170 BestWidth = Context.Target.getLongLongWidth(); 4171 4172 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4173 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4174 BestType = Context.LongLongTy; 4175 } 4176 } 4177 } else { 4178 // If there is no negative value, figure out which of uint, ulong, ulonglong 4179 // fits. 4180 if (NumPositiveBits <= IntWidth) { 4181 BestType = Context.UnsignedIntTy; 4182 BestWidth = IntWidth; 4183 } else if (NumPositiveBits <= 4184 (BestWidth = Context.Target.getLongWidth())) { 4185 BestType = Context.UnsignedLongTy; 4186 } else { 4187 BestWidth = Context.Target.getLongLongWidth(); 4188 assert(NumPositiveBits <= BestWidth && 4189 "How could an initializer get larger than ULL?"); 4190 BestType = Context.UnsignedLongLongTy; 4191 } 4192 } 4193 4194 // Loop over all of the enumerator constants, changing their types to match 4195 // the type of the enum if needed. 4196 for (unsigned i = 0; i != NumElements; ++i) { 4197 EnumConstantDecl *ECD = 4198 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4199 if (!ECD) continue; // Already issued a diagnostic. 4200 4201 // Standard C says the enumerators have int type, but we allow, as an 4202 // extension, the enumerators to be larger than int size. If each 4203 // enumerator value fits in an int, type it as an int, otherwise type it the 4204 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4205 // that X has type 'int', not 'unsigned'. 4206 if (ECD->getType() == Context.IntTy) { 4207 // Make sure the init value is signed. 4208 llvm::APSInt IV = ECD->getInitVal(); 4209 IV.setIsSigned(true); 4210 ECD->setInitVal(IV); 4211 4212 if (getLangOptions().CPlusPlus) 4213 // C++ [dcl.enum]p4: Following the closing brace of an 4214 // enum-specifier, each enumerator has the type of its 4215 // enumeration. 4216 ECD->setType(EnumType); 4217 continue; // Already int type. 4218 } 4219 4220 // Determine whether the value fits into an int. 4221 llvm::APSInt InitVal = ECD->getInitVal(); 4222 bool FitsInInt; 4223 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4224 FitsInInt = InitVal.getActiveBits() < IntWidth; 4225 else 4226 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4227 4228 // If it fits into an integer type, force it. Otherwise force it to match 4229 // the enum decl type. 4230 QualType NewTy; 4231 unsigned NewWidth; 4232 bool NewSign; 4233 if (FitsInInt) { 4234 NewTy = Context.IntTy; 4235 NewWidth = IntWidth; 4236 NewSign = true; 4237 } else if (ECD->getType() == BestType) { 4238 // Already the right type! 4239 if (getLangOptions().CPlusPlus) 4240 // C++ [dcl.enum]p4: Following the closing brace of an 4241 // enum-specifier, each enumerator has the type of its 4242 // enumeration. 4243 ECD->setType(EnumType); 4244 continue; 4245 } else { 4246 NewTy = BestType; 4247 NewWidth = BestWidth; 4248 NewSign = BestType->isSignedIntegerType(); 4249 } 4250 4251 // Adjust the APSInt value. 4252 InitVal.extOrTrunc(NewWidth); 4253 InitVal.setIsSigned(NewSign); 4254 ECD->setInitVal(InitVal); 4255 4256 // Adjust the Expr initializer and type. 4257 if (ECD->getInitExpr()) 4258 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4259 /*isLvalue=*/false)); 4260 if (getLangOptions().CPlusPlus) 4261 // C++ [dcl.enum]p4: Following the closing brace of an 4262 // enum-specifier, each enumerator has the type of its 4263 // enumeration. 4264 ECD->setType(EnumType); 4265 else 4266 ECD->setType(NewTy); 4267 } 4268 4269 Enum->completeDefinition(Context, BestType); 4270} 4271 4272Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4273 ExprArg expr) { 4274 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4275 4276 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4277 Loc, AsmString)); 4278} 4279 4280