SemaDecl.cpp revision dabbad04ee3173f76b324d3825ede0287a304022
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/Parse/DeclSpec.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31using namespace clang; 32 33/// getDeclName - Return a pretty name for the specified decl if possible, or 34/// an empty string if not. This is used for pretty crash reporting. 35std::string Sema::getDeclName(DeclPtrTy d) { 36 Decl *D = d.getAs<Decl>(); 37 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 38 return DN->getQualifiedNameAsString(); 39 return ""; 40} 41 42Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 43 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 44} 45 46/// \brief If the identifier refers to a type name within this scope, 47/// return the declaration of that type. 48/// 49/// This routine performs ordinary name lookup of the identifier II 50/// within the given scope, with optional C++ scope specifier SS, to 51/// determine whether the name refers to a type. If so, returns an 52/// opaque pointer (actually a QualType) corresponding to that 53/// type. Otherwise, returns NULL. 54/// 55/// If name lookup results in an ambiguity, this routine will complain 56/// and then return NULL. 57Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 58 Scope *S, const CXXScopeSpec *SS) { 59 // C++ [temp.res]p3: 60 // A qualified-id that refers to a type and in which the 61 // nested-name-specifier depends on a template-parameter (14.6.2) 62 // shall be prefixed by the keyword typename to indicate that the 63 // qualified-id denotes a type, forming an 64 // elaborated-type-specifier (7.1.5.3). 65 // 66 // We therefore do not perform any name lookup up SS is a dependent 67 // scope name. FIXME: we will need to perform a special kind of 68 // lookup if the scope specifier names a member of the current 69 // instantiation. 70 if (SS && isDependentScopeSpecifier(*SS)) 71 return 0; 72 73 NamedDecl *IIDecl = 0; 74 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 75 false, false); 76 switch (Result.getKind()) { 77 case LookupResult::NotFound: 78 case LookupResult::FoundOverloaded: 79 return 0; 80 81 case LookupResult::AmbiguousBaseSubobjectTypes: 82 case LookupResult::AmbiguousBaseSubobjects: 83 case LookupResult::AmbiguousReference: { 84 // Look to see if we have a type anywhere in the list of results. 85 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 86 Res != ResEnd; ++Res) { 87 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 88 if (!IIDecl || 89 (*Res)->getLocation().getRawEncoding() < 90 IIDecl->getLocation().getRawEncoding()) 91 IIDecl = *Res; 92 } 93 } 94 95 if (!IIDecl) { 96 // None of the entities we found is a type, so there is no way 97 // to even assume that the result is a type. In this case, don't 98 // complain about the ambiguity. The parser will either try to 99 // perform this lookup again (e.g., as an object name), which 100 // will produce the ambiguity, or will complain that it expected 101 // a type name. 102 Result.Destroy(); 103 return 0; 104 } 105 106 // We found a type within the ambiguous lookup; diagnose the 107 // ambiguity and then return that type. This might be the right 108 // answer, or it might not be, but it suppresses any attempt to 109 // perform the name lookup again. 110 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 111 break; 112 } 113 114 case LookupResult::Found: 115 IIDecl = Result.getAsDecl(); 116 break; 117 } 118 119 if (IIDecl) { 120 QualType T; 121 122 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 123 // Check whether we can use this type 124 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 125 126 T = Context.getTypeDeclType(TD); 127 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 128 // Check whether we can use this interface. 129 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 130 131 T = Context.getObjCInterfaceType(IDecl); 132 } else 133 return 0; 134 135 if (SS) 136 T = getQualifiedNameType(*SS, T); 137 138 return T.getAsOpaquePtr(); 139 } 140 141 return 0; 142} 143 144/// isTagName() - This method is called *for error recovery purposes only* 145/// to determine if the specified name is a valid tag name ("struct foo"). If 146/// so, this returns the TST for the tag corresponding to it (TST_enum, 147/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 148/// where the user forgot to specify the tag. 149DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 150 // Do a tag name lookup in this scope. 151 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 152 if (R.getKind() == LookupResult::Found) 153 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 154 switch (TD->getTagKind()) { 155 case TagDecl::TK_struct: return DeclSpec::TST_struct; 156 case TagDecl::TK_union: return DeclSpec::TST_union; 157 case TagDecl::TK_class: return DeclSpec::TST_class; 158 case TagDecl::TK_enum: return DeclSpec::TST_enum; 159 } 160 } 161 162 return DeclSpec::TST_unspecified; 163} 164 165 166 167DeclContext *Sema::getContainingDC(DeclContext *DC) { 168 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 169 // A C++ out-of-line method will return to the file declaration context. 170 if (MD->isOutOfLineDefinition()) 171 return MD->getLexicalDeclContext(); 172 173 // A C++ inline method is parsed *after* the topmost class it was declared 174 // in is fully parsed (it's "complete"). 175 // The parsing of a C++ inline method happens at the declaration context of 176 // the topmost (non-nested) class it is lexically declared in. 177 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 178 DC = MD->getParent(); 179 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 180 DC = RD; 181 182 // Return the declaration context of the topmost class the inline method is 183 // declared in. 184 return DC; 185 } 186 187 if (isa<ObjCMethodDecl>(DC)) 188 return Context.getTranslationUnitDecl(); 189 190 return DC->getLexicalParent(); 191} 192 193void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 194 assert(getContainingDC(DC) == CurContext && 195 "The next DeclContext should be lexically contained in the current one."); 196 CurContext = DC; 197 S->setEntity(DC); 198} 199 200void Sema::PopDeclContext() { 201 assert(CurContext && "DeclContext imbalance!"); 202 203 CurContext = getContainingDC(CurContext); 204} 205 206/// \brief Determine whether we allow overloading of the function 207/// PrevDecl with another declaration. 208/// 209/// This routine determines whether overloading is possible, not 210/// whether some new function is actually an overload. It will return 211/// true in C++ (where we can always provide overloads) or, as an 212/// extension, in C when the previous function is already an 213/// overloaded function declaration or has the "overloadable" 214/// attribute. 215static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 216 if (Context.getLangOptions().CPlusPlus) 217 return true; 218 219 if (isa<OverloadedFunctionDecl>(PrevDecl)) 220 return true; 221 222 return PrevDecl->getAttr<OverloadableAttr>() != 0; 223} 224 225/// Add this decl to the scope shadowed decl chains. 226void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 227 // Move up the scope chain until we find the nearest enclosing 228 // non-transparent context. The declaration will be introduced into this 229 // scope. 230 while (S->getEntity() && 231 ((DeclContext *)S->getEntity())->isTransparentContext()) 232 S = S->getParent(); 233 234 S->AddDecl(DeclPtrTy::make(D)); 235 236 // Add scoped declarations into their context, so that they can be 237 // found later. Declarations without a context won't be inserted 238 // into any context. 239 CurContext->addDecl(Context, D); 240 241 // C++ [basic.scope]p4: 242 // -- exactly one declaration shall declare a class name or 243 // enumeration name that is not a typedef name and the other 244 // declarations shall all refer to the same object or 245 // enumerator, or all refer to functions and function templates; 246 // in this case the class name or enumeration name is hidden. 247 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 248 // We are pushing the name of a tag (enum or class). 249 if (CurContext->getLookupContext() 250 == TD->getDeclContext()->getLookupContext()) { 251 // We're pushing the tag into the current context, which might 252 // require some reshuffling in the identifier resolver. 253 IdentifierResolver::iterator 254 I = IdResolver.begin(TD->getDeclName()), 255 IEnd = IdResolver.end(); 256 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 257 NamedDecl *PrevDecl = *I; 258 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 259 PrevDecl = *I, ++I) { 260 if (TD->declarationReplaces(*I)) { 261 // This is a redeclaration. Remove it from the chain and 262 // break out, so that we'll add in the shadowed 263 // declaration. 264 S->RemoveDecl(DeclPtrTy::make(*I)); 265 if (PrevDecl == *I) { 266 IdResolver.RemoveDecl(*I); 267 IdResolver.AddDecl(TD); 268 return; 269 } else { 270 IdResolver.RemoveDecl(*I); 271 break; 272 } 273 } 274 } 275 276 // There is already a declaration with the same name in the same 277 // scope, which is not a tag declaration. It must be found 278 // before we find the new declaration, so insert the new 279 // declaration at the end of the chain. 280 IdResolver.AddShadowedDecl(TD, PrevDecl); 281 282 return; 283 } 284 } 285 } else if (isa<FunctionDecl>(D) && 286 AllowOverloadingOfFunction(D, Context)) { 287 // We are pushing the name of a function, which might be an 288 // overloaded name. 289 FunctionDecl *FD = cast<FunctionDecl>(D); 290 IdentifierResolver::iterator Redecl 291 = std::find_if(IdResolver.begin(FD->getDeclName()), 292 IdResolver.end(), 293 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 294 FD)); 295 if (Redecl != IdResolver.end() && 296 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 297 // There is already a declaration of a function on our 298 // IdResolver chain. Replace it with this declaration. 299 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 300 IdResolver.RemoveDecl(*Redecl); 301 } 302 } 303 304 IdResolver.AddDecl(D); 305} 306 307void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 308 if (S->decl_empty()) return; 309 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 310 "Scope shouldn't contain decls!"); 311 312 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 313 I != E; ++I) { 314 Decl *TmpD = (*I).getAs<Decl>(); 315 assert(TmpD && "This decl didn't get pushed??"); 316 317 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 318 NamedDecl *D = cast<NamedDecl>(TmpD); 319 320 if (!D->getDeclName()) continue; 321 322 // Remove this name from our lexical scope. 323 IdResolver.RemoveDecl(D); 324 } 325} 326 327/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 328/// return 0 if one not found. 329ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 330 // The third "scope" argument is 0 since we aren't enabling lazy built-in 331 // creation from this context. 332 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 333 334 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 335} 336 337/// getNonFieldDeclScope - Retrieves the innermost scope, starting 338/// from S, where a non-field would be declared. This routine copes 339/// with the difference between C and C++ scoping rules in structs and 340/// unions. For example, the following code is well-formed in C but 341/// ill-formed in C++: 342/// @code 343/// struct S6 { 344/// enum { BAR } e; 345/// }; 346/// 347/// void test_S6() { 348/// struct S6 a; 349/// a.e = BAR; 350/// } 351/// @endcode 352/// For the declaration of BAR, this routine will return a different 353/// scope. The scope S will be the scope of the unnamed enumeration 354/// within S6. In C++, this routine will return the scope associated 355/// with S6, because the enumeration's scope is a transparent 356/// context but structures can contain non-field names. In C, this 357/// routine will return the translation unit scope, since the 358/// enumeration's scope is a transparent context and structures cannot 359/// contain non-field names. 360Scope *Sema::getNonFieldDeclScope(Scope *S) { 361 while (((S->getFlags() & Scope::DeclScope) == 0) || 362 (S->getEntity() && 363 ((DeclContext *)S->getEntity())->isTransparentContext()) || 364 (S->isClassScope() && !getLangOptions().CPlusPlus)) 365 S = S->getParent(); 366 return S; 367} 368 369void Sema::InitBuiltinVaListType() { 370 if (!Context.getBuiltinVaListType().isNull()) 371 return; 372 373 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 374 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 375 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 376 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 377} 378 379/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 380/// file scope. lazily create a decl for it. ForRedeclaration is true 381/// if we're creating this built-in in anticipation of redeclaring the 382/// built-in. 383NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 384 Scope *S, bool ForRedeclaration, 385 SourceLocation Loc) { 386 Builtin::ID BID = (Builtin::ID)bid; 387 388 if (Context.BuiltinInfo.hasVAListUse(BID)) 389 InitBuiltinVaListType(); 390 391 Builtin::Context::GetBuiltinTypeError Error; 392 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 393 switch (Error) { 394 case Builtin::Context::GE_None: 395 // Okay 396 break; 397 398 case Builtin::Context::GE_Missing_FILE: 399 if (ForRedeclaration) 400 Diag(Loc, diag::err_implicit_decl_requires_stdio) 401 << Context.BuiltinInfo.GetName(BID); 402 return 0; 403 } 404 405 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 406 Diag(Loc, diag::ext_implicit_lib_function_decl) 407 << Context.BuiltinInfo.GetName(BID) 408 << R; 409 if (Context.BuiltinInfo.getHeaderName(BID) && 410 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 411 != Diagnostic::Ignored) 412 Diag(Loc, diag::note_please_include_header) 413 << Context.BuiltinInfo.getHeaderName(BID) 414 << Context.BuiltinInfo.GetName(BID); 415 } 416 417 FunctionDecl *New = FunctionDecl::Create(Context, 418 Context.getTranslationUnitDecl(), 419 Loc, II, R, 420 FunctionDecl::Extern, false, 421 /*hasPrototype=*/true); 422 New->setImplicit(); 423 424 // Create Decl objects for each parameter, adding them to the 425 // FunctionDecl. 426 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 427 llvm::SmallVector<ParmVarDecl*, 16> Params; 428 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 429 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 430 FT->getArgType(i), VarDecl::None, 0)); 431 New->setParams(Context, &Params[0], Params.size()); 432 } 433 434 AddKnownFunctionAttributes(New); 435 436 // TUScope is the translation-unit scope to insert this function into. 437 // FIXME: This is hideous. We need to teach PushOnScopeChains to 438 // relate Scopes to DeclContexts, and probably eliminate CurContext 439 // entirely, but we're not there yet. 440 DeclContext *SavedContext = CurContext; 441 CurContext = Context.getTranslationUnitDecl(); 442 PushOnScopeChains(New, TUScope); 443 CurContext = SavedContext; 444 return New; 445} 446 447/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 448/// everything from the standard library is defined. 449NamespaceDecl *Sema::GetStdNamespace() { 450 if (!StdNamespace) { 451 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 452 DeclContext *Global = Context.getTranslationUnitDecl(); 453 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 454 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 455 } 456 return StdNamespace; 457} 458 459/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 460/// same name and scope as a previous declaration 'Old'. Figure out 461/// how to resolve this situation, merging decls or emitting 462/// diagnostics as appropriate. Returns true if there was an error, 463/// false otherwise. 464/// 465bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 466 bool objc_types = false; 467 // Allow multiple definitions for ObjC built-in typedefs. 468 // FIXME: Verify the underlying types are equivalent! 469 if (getLangOptions().ObjC1) { 470 const IdentifierInfo *TypeID = New->getIdentifier(); 471 switch (TypeID->getLength()) { 472 default: break; 473 case 2: 474 if (!TypeID->isStr("id")) 475 break; 476 Context.setObjCIdType(New); 477 objc_types = true; 478 break; 479 case 5: 480 if (!TypeID->isStr("Class")) 481 break; 482 Context.setObjCClassType(New); 483 objc_types = true; 484 return false; 485 case 3: 486 if (!TypeID->isStr("SEL")) 487 break; 488 Context.setObjCSelType(New); 489 objc_types = true; 490 return false; 491 case 8: 492 if (!TypeID->isStr("Protocol")) 493 break; 494 Context.setObjCProtoType(New->getUnderlyingType()); 495 objc_types = true; 496 return false; 497 } 498 // Fall through - the typedef name was not a builtin type. 499 } 500 // Verify the old decl was also a type. 501 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 502 if (!Old) { 503 Diag(New->getLocation(), diag::err_redefinition_different_kind) 504 << New->getDeclName(); 505 if (!objc_types) 506 Diag(OldD->getLocation(), diag::note_previous_definition); 507 return true; 508 } 509 510 // Determine the "old" type we'll use for checking and diagnostics. 511 QualType OldType; 512 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 513 OldType = OldTypedef->getUnderlyingType(); 514 else 515 OldType = Context.getTypeDeclType(Old); 516 517 // If the typedef types are not identical, reject them in all languages and 518 // with any extensions enabled. 519 520 if (OldType != New->getUnderlyingType() && 521 Context.getCanonicalType(OldType) != 522 Context.getCanonicalType(New->getUnderlyingType())) { 523 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 524 << New->getUnderlyingType() << OldType; 525 if (!objc_types) 526 Diag(Old->getLocation(), diag::note_previous_definition); 527 return true; 528 } 529 if (objc_types) return false; 530 if (getLangOptions().Microsoft) return false; 531 532 // C++ [dcl.typedef]p2: 533 // In a given non-class scope, a typedef specifier can be used to 534 // redefine the name of any type declared in that scope to refer 535 // to the type to which it already refers. 536 if (getLangOptions().CPlusPlus) { 537 if (!isa<CXXRecordDecl>(CurContext)) 538 return false; 539 Diag(New->getLocation(), diag::err_redefinition) 540 << New->getDeclName(); 541 Diag(Old->getLocation(), diag::note_previous_definition); 542 return true; 543 } 544 545 // If we have a redefinition of a typedef in C, emit a warning. This warning 546 // is normally mapped to an error, but can be controlled with 547 // -Wtypedef-redefinition. 548 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 549 << New->getDeclName(); 550 Diag(Old->getLocation(), diag::note_previous_definition); 551 return false; 552} 553 554/// DeclhasAttr - returns true if decl Declaration already has the target 555/// attribute. 556static bool DeclHasAttr(const Decl *decl, const Attr *target) { 557 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 558 if (attr->getKind() == target->getKind()) 559 return true; 560 561 return false; 562} 563 564/// MergeAttributes - append attributes from the Old decl to the New one. 565static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 566 Attr *attr = const_cast<Attr*>(Old->getAttrs()); 567 568 while (attr) { 569 Attr *tmp = attr; 570 attr = attr->getNext(); 571 572 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 573 tmp->setInherited(true); 574 New->addAttr(tmp); 575 } else { 576 tmp->setNext(0); 577 tmp->Destroy(C); 578 } 579 } 580 581 Old->invalidateAttrs(); 582} 583 584/// Used in MergeFunctionDecl to keep track of function parameters in 585/// C. 586struct GNUCompatibleParamWarning { 587 ParmVarDecl *OldParm; 588 ParmVarDecl *NewParm; 589 QualType PromotedType; 590}; 591 592/// MergeFunctionDecl - We just parsed a function 'New' from 593/// declarator D which has the same name and scope as a previous 594/// declaration 'Old'. Figure out how to resolve this situation, 595/// merging decls or emitting diagnostics as appropriate. 596/// 597/// In C++, New and Old must be declarations that are not 598/// overloaded. Use IsOverload to determine whether New and Old are 599/// overloaded, and to select the Old declaration that New should be 600/// merged with. 601/// 602/// Returns true if there was an error, false otherwise. 603bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 604 assert(!isa<OverloadedFunctionDecl>(OldD) && 605 "Cannot merge with an overloaded function declaration"); 606 607 // Verify the old decl was also a function. 608 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 609 if (!Old) { 610 Diag(New->getLocation(), diag::err_redefinition_different_kind) 611 << New->getDeclName(); 612 Diag(OldD->getLocation(), diag::note_previous_definition); 613 return true; 614 } 615 616 // Determine whether the previous declaration was a definition, 617 // implicit declaration, or a declaration. 618 diag::kind PrevDiag; 619 if (Old->isThisDeclarationADefinition()) 620 PrevDiag = diag::note_previous_definition; 621 else if (Old->isImplicit()) 622 PrevDiag = diag::note_previous_implicit_declaration; 623 else 624 PrevDiag = diag::note_previous_declaration; 625 626 QualType OldQType = Context.getCanonicalType(Old->getType()); 627 QualType NewQType = Context.getCanonicalType(New->getType()); 628 629 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 630 New->getStorageClass() == FunctionDecl::Static && 631 Old->getStorageClass() != FunctionDecl::Static) { 632 Diag(New->getLocation(), diag::err_static_non_static) 633 << New; 634 Diag(Old->getLocation(), PrevDiag); 635 return true; 636 } 637 638 if (getLangOptions().CPlusPlus) { 639 // (C++98 13.1p2): 640 // Certain function declarations cannot be overloaded: 641 // -- Function declarations that differ only in the return type 642 // cannot be overloaded. 643 QualType OldReturnType 644 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 645 QualType NewReturnType 646 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 647 if (OldReturnType != NewReturnType) { 648 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 649 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 650 return true; 651 } 652 653 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 654 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 655 if (OldMethod && NewMethod && 656 OldMethod->getLexicalDeclContext() == 657 NewMethod->getLexicalDeclContext()) { 658 // -- Member function declarations with the same name and the 659 // same parameter types cannot be overloaded if any of them 660 // is a static member function declaration. 661 if (OldMethod->isStatic() || NewMethod->isStatic()) { 662 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 663 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 664 return true; 665 } 666 667 // C++ [class.mem]p1: 668 // [...] A member shall not be declared twice in the 669 // member-specification, except that a nested class or member 670 // class template can be declared and then later defined. 671 unsigned NewDiag; 672 if (isa<CXXConstructorDecl>(OldMethod)) 673 NewDiag = diag::err_constructor_redeclared; 674 else if (isa<CXXDestructorDecl>(NewMethod)) 675 NewDiag = diag::err_destructor_redeclared; 676 else if (isa<CXXConversionDecl>(NewMethod)) 677 NewDiag = diag::err_conv_function_redeclared; 678 else 679 NewDiag = diag::err_member_redeclared; 680 681 Diag(New->getLocation(), NewDiag); 682 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 683 } 684 685 // (C++98 8.3.5p3): 686 // All declarations for a function shall agree exactly in both the 687 // return type and the parameter-type-list. 688 if (OldQType == NewQType) 689 return MergeCompatibleFunctionDecls(New, Old); 690 691 // Fall through for conflicting redeclarations and redefinitions. 692 } 693 694 // C: Function types need to be compatible, not identical. This handles 695 // duplicate function decls like "void f(int); void f(enum X);" properly. 696 if (!getLangOptions().CPlusPlus && 697 Context.typesAreCompatible(OldQType, NewQType)) { 698 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 699 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 700 const FunctionProtoType *OldProto = 0; 701 if (isa<FunctionNoProtoType>(NewFuncType) && 702 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 703 // The old declaration provided a function prototype, but the 704 // new declaration does not. Merge in the prototype. 705 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 706 OldProto->arg_type_end()); 707 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 708 &ParamTypes[0], ParamTypes.size(), 709 OldProto->isVariadic(), 710 OldProto->getTypeQuals()); 711 New->setType(NewQType); 712 New->setInheritedPrototype(); 713 714 // Synthesize a parameter for each argument type. 715 llvm::SmallVector<ParmVarDecl*, 16> Params; 716 for (FunctionProtoType::arg_type_iterator 717 ParamType = OldProto->arg_type_begin(), 718 ParamEnd = OldProto->arg_type_end(); 719 ParamType != ParamEnd; ++ParamType) { 720 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 721 SourceLocation(), 0, 722 *ParamType, VarDecl::None, 723 0); 724 Param->setImplicit(); 725 Params.push_back(Param); 726 } 727 728 New->setParams(Context, &Params[0], Params.size()); 729 } 730 731 return MergeCompatibleFunctionDecls(New, Old); 732 } 733 734 // GNU C permits a K&R definition to follow a prototype declaration 735 // if the declared types of the parameters in the K&R definition 736 // match the types in the prototype declaration, even when the 737 // promoted types of the parameters from the K&R definition differ 738 // from the types in the prototype. GCC then keeps the types from 739 // the prototype. 740 if (!getLangOptions().CPlusPlus && 741 !getLangOptions().NoExtensions && 742 Old->hasPrototype() && !New->hasPrototype() && 743 New->getType()->getAsFunctionProtoType() && 744 Old->getNumParams() == New->getNumParams()) { 745 llvm::SmallVector<QualType, 16> ArgTypes; 746 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 747 const FunctionProtoType *OldProto 748 = Old->getType()->getAsFunctionProtoType(); 749 const FunctionProtoType *NewProto 750 = New->getType()->getAsFunctionProtoType(); 751 752 // Determine whether this is the GNU C extension. 753 bool GNUCompatible = 754 Context.typesAreCompatible(OldProto->getResultType(), 755 NewProto->getResultType()) && 756 (OldProto->isVariadic() == NewProto->isVariadic()); 757 for (unsigned Idx = 0, End = Old->getNumParams(); 758 GNUCompatible && Idx != End; ++Idx) { 759 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 760 ParmVarDecl *NewParm = New->getParamDecl(Idx); 761 if (Context.typesAreCompatible(OldParm->getType(), 762 NewProto->getArgType(Idx))) { 763 ArgTypes.push_back(NewParm->getType()); 764 } else if (Context.typesAreCompatible(OldParm->getType(), 765 NewParm->getType())) { 766 GNUCompatibleParamWarning Warn 767 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 768 Warnings.push_back(Warn); 769 ArgTypes.push_back(NewParm->getType()); 770 } else 771 GNUCompatible = false; 772 } 773 774 if (GNUCompatible) { 775 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 776 Diag(Warnings[Warn].NewParm->getLocation(), 777 diag::ext_param_promoted_not_compatible_with_prototype) 778 << Warnings[Warn].PromotedType 779 << Warnings[Warn].OldParm->getType(); 780 Diag(Warnings[Warn].OldParm->getLocation(), 781 diag::note_previous_declaration); 782 } 783 784 New->setType(Context.getFunctionType(NewProto->getResultType(), 785 &ArgTypes[0], ArgTypes.size(), 786 NewProto->isVariadic(), 787 NewProto->getTypeQuals())); 788 return MergeCompatibleFunctionDecls(New, Old); 789 } 790 791 // Fall through to diagnose conflicting types. 792 } 793 794 // A function that has already been declared has been redeclared or defined 795 // with a different type- show appropriate diagnostic 796 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 797 // The user has declared a builtin function with an incompatible 798 // signature. 799 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 800 // The function the user is redeclaring is a library-defined 801 // function like 'malloc' or 'printf'. Warn about the 802 // redeclaration, then pretend that we don't know about this 803 // library built-in. 804 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 805 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 806 << Old << Old->getType(); 807 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 808 Old->setInvalidDecl(); 809 return false; 810 } 811 812 PrevDiag = diag::note_previous_builtin_declaration; 813 } 814 815 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 816 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 817 return true; 818} 819 820/// \brief Completes the merge of two function declarations that are 821/// known to be compatible. 822/// 823/// This routine handles the merging of attributes and other 824/// properties of function declarations form the old declaration to 825/// the new declaration, once we know that New is in fact a 826/// redeclaration of Old. 827/// 828/// \returns false 829bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 830 // Merge the attributes 831 MergeAttributes(New, Old, Context); 832 833 // Merge the storage class. 834 New->setStorageClass(Old->getStorageClass()); 835 836 // FIXME: need to implement inline semantics 837 838 // Merge "pure" flag. 839 if (Old->isPure()) 840 New->setPure(); 841 842 // Merge the "deleted" flag. 843 if (Old->isDeleted()) 844 New->setDeleted(); 845 846 if (getLangOptions().CPlusPlus) 847 return MergeCXXFunctionDecl(New, Old); 848 849 return false; 850} 851 852/// MergeVarDecl - We just parsed a variable 'New' which has the same name 853/// and scope as a previous declaration 'Old'. Figure out how to resolve this 854/// situation, merging decls or emitting diagnostics as appropriate. 855/// 856/// Tentative definition rules (C99 6.9.2p2) are checked by 857/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 858/// definitions here, since the initializer hasn't been attached. 859/// 860bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 861 // Verify the old decl was also a variable. 862 VarDecl *Old = dyn_cast<VarDecl>(OldD); 863 if (!Old) { 864 Diag(New->getLocation(), diag::err_redefinition_different_kind) 865 << New->getDeclName(); 866 Diag(OldD->getLocation(), diag::note_previous_definition); 867 return true; 868 } 869 870 MergeAttributes(New, Old, Context); 871 872 // Merge the types 873 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 874 if (MergedT.isNull()) { 875 Diag(New->getLocation(), diag::err_redefinition_different_type) 876 << New->getDeclName(); 877 Diag(Old->getLocation(), diag::note_previous_definition); 878 return true; 879 } 880 New->setType(MergedT); 881 882 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 883 if (New->getStorageClass() == VarDecl::Static && 884 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 885 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 886 Diag(Old->getLocation(), diag::note_previous_definition); 887 return true; 888 } 889 // C99 6.2.2p4: 890 // For an identifier declared with the storage-class specifier 891 // extern in a scope in which a prior declaration of that 892 // identifier is visible,23) if the prior declaration specifies 893 // internal or external linkage, the linkage of the identifier at 894 // the later declaration is the same as the linkage specified at 895 // the prior declaration. If no prior declaration is visible, or 896 // if the prior declaration specifies no linkage, then the 897 // identifier has external linkage. 898 if (New->hasExternalStorage() && Old->hasLinkage()) 899 /* Okay */; 900 else if (New->getStorageClass() != VarDecl::Static && 901 Old->getStorageClass() == VarDecl::Static) { 902 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 903 Diag(Old->getLocation(), diag::note_previous_definition); 904 return true; 905 } 906 907 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 908 909 // FIXME: The test for external storage here seems wrong? We still 910 // need to check for mismatches. 911 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 912 // Don't complain about out-of-line definitions of static members. 913 !(Old->getLexicalDeclContext()->isRecord() && 914 !New->getLexicalDeclContext()->isRecord())) { 915 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 916 Diag(Old->getLocation(), diag::note_previous_definition); 917 return true; 918 } 919 920 // Keep a chain of previous declarations. 921 New->setPreviousDeclaration(Old); 922 923 return false; 924} 925 926/// CheckParmsForFunctionDef - Check that the parameters of the given 927/// function are appropriate for the definition of a function. This 928/// takes care of any checks that cannot be performed on the 929/// declaration itself, e.g., that the types of each of the function 930/// parameters are complete. 931bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 932 bool HasInvalidParm = false; 933 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 934 ParmVarDecl *Param = FD->getParamDecl(p); 935 936 // C99 6.7.5.3p4: the parameters in a parameter type list in a 937 // function declarator that is part of a function definition of 938 // that function shall not have incomplete type. 939 // 940 // This is also C++ [dcl.fct]p6. 941 if (!Param->isInvalidDecl() && 942 RequireCompleteType(Param->getLocation(), Param->getType(), 943 diag::err_typecheck_decl_incomplete_type)) { 944 Param->setInvalidDecl(); 945 HasInvalidParm = true; 946 } 947 948 // C99 6.9.1p5: If the declarator includes a parameter type list, the 949 // declaration of each parameter shall include an identifier. 950 if (Param->getIdentifier() == 0 && 951 !Param->isImplicit() && 952 !getLangOptions().CPlusPlus) 953 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 954 } 955 956 return HasInvalidParm; 957} 958 959/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 960/// no declarator (e.g. "struct foo;") is parsed. 961Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 962 // FIXME: Error on auto/register at file scope 963 // FIXME: Error on inline/virtual/explicit 964 // FIXME: Error on invalid restrict 965 // FIXME: Warn on useless const/volatile 966 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 967 // FIXME: Warn on useless attributes 968 969 TagDecl *Tag = 0; 970 if (DS.getTypeSpecType() == DeclSpec::TST_class || 971 DS.getTypeSpecType() == DeclSpec::TST_struct || 972 DS.getTypeSpecType() == DeclSpec::TST_union || 973 DS.getTypeSpecType() == DeclSpec::TST_enum) 974 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 975 976 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 977 if (!Record->getDeclName() && Record->isDefinition() && 978 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 979 if (getLangOptions().CPlusPlus || 980 Record->getDeclContext()->isRecord()) 981 return BuildAnonymousStructOrUnion(S, DS, Record); 982 983 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 984 << DS.getSourceRange(); 985 } 986 987 // Microsoft allows unnamed struct/union fields. Don't complain 988 // about them. 989 // FIXME: Should we support Microsoft's extensions in this area? 990 if (Record->getDeclName() && getLangOptions().Microsoft) 991 return DeclPtrTy::make(Tag); 992 } 993 994 if (!DS.isMissingDeclaratorOk() && 995 DS.getTypeSpecType() != DeclSpec::TST_error) { 996 // Warn about typedefs of enums without names, since this is an 997 // extension in both Microsoft an GNU. 998 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 999 Tag && isa<EnumDecl>(Tag)) { 1000 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1001 << DS.getSourceRange(); 1002 return DeclPtrTy::make(Tag); 1003 } 1004 1005 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1006 << DS.getSourceRange(); 1007 return DeclPtrTy(); 1008 } 1009 1010 return DeclPtrTy::make(Tag); 1011} 1012 1013/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1014/// anonymous struct or union AnonRecord into the owning context Owner 1015/// and scope S. This routine will be invoked just after we realize 1016/// that an unnamed union or struct is actually an anonymous union or 1017/// struct, e.g., 1018/// 1019/// @code 1020/// union { 1021/// int i; 1022/// float f; 1023/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1024/// // f into the surrounding scope.x 1025/// @endcode 1026/// 1027/// This routine is recursive, injecting the names of nested anonymous 1028/// structs/unions into the owning context and scope as well. 1029bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1030 RecordDecl *AnonRecord) { 1031 bool Invalid = false; 1032 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1033 FEnd = AnonRecord->field_end(Context); 1034 F != FEnd; ++F) { 1035 if ((*F)->getDeclName()) { 1036 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1037 LookupOrdinaryName, true); 1038 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1039 // C++ [class.union]p2: 1040 // The names of the members of an anonymous union shall be 1041 // distinct from the names of any other entity in the 1042 // scope in which the anonymous union is declared. 1043 unsigned diagKind 1044 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1045 : diag::err_anonymous_struct_member_redecl; 1046 Diag((*F)->getLocation(), diagKind) 1047 << (*F)->getDeclName(); 1048 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1049 Invalid = true; 1050 } else { 1051 // C++ [class.union]p2: 1052 // For the purpose of name lookup, after the anonymous union 1053 // definition, the members of the anonymous union are 1054 // considered to have been defined in the scope in which the 1055 // anonymous union is declared. 1056 Owner->makeDeclVisibleInContext(Context, *F); 1057 S->AddDecl(DeclPtrTy::make(*F)); 1058 IdResolver.AddDecl(*F); 1059 } 1060 } else if (const RecordType *InnerRecordType 1061 = (*F)->getType()->getAsRecordType()) { 1062 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1063 if (InnerRecord->isAnonymousStructOrUnion()) 1064 Invalid = Invalid || 1065 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1066 } 1067 } 1068 1069 return Invalid; 1070} 1071 1072/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1073/// anonymous structure or union. Anonymous unions are a C++ feature 1074/// (C++ [class.union]) and a GNU C extension; anonymous structures 1075/// are a GNU C and GNU C++ extension. 1076Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1077 RecordDecl *Record) { 1078 DeclContext *Owner = Record->getDeclContext(); 1079 1080 // Diagnose whether this anonymous struct/union is an extension. 1081 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1082 Diag(Record->getLocation(), diag::ext_anonymous_union); 1083 else if (!Record->isUnion()) 1084 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1085 1086 // C and C++ require different kinds of checks for anonymous 1087 // structs/unions. 1088 bool Invalid = false; 1089 if (getLangOptions().CPlusPlus) { 1090 const char* PrevSpec = 0; 1091 // C++ [class.union]p3: 1092 // Anonymous unions declared in a named namespace or in the 1093 // global namespace shall be declared static. 1094 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1095 (isa<TranslationUnitDecl>(Owner) || 1096 (isa<NamespaceDecl>(Owner) && 1097 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1098 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1099 Invalid = true; 1100 1101 // Recover by adding 'static'. 1102 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1103 } 1104 // C++ [class.union]p3: 1105 // A storage class is not allowed in a declaration of an 1106 // anonymous union in a class scope. 1107 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1108 isa<RecordDecl>(Owner)) { 1109 Diag(DS.getStorageClassSpecLoc(), 1110 diag::err_anonymous_union_with_storage_spec); 1111 Invalid = true; 1112 1113 // Recover by removing the storage specifier. 1114 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1115 PrevSpec); 1116 } 1117 1118 // C++ [class.union]p2: 1119 // The member-specification of an anonymous union shall only 1120 // define non-static data members. [Note: nested types and 1121 // functions cannot be declared within an anonymous union. ] 1122 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1123 MemEnd = Record->decls_end(Context); 1124 Mem != MemEnd; ++Mem) { 1125 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1126 // C++ [class.union]p3: 1127 // An anonymous union shall not have private or protected 1128 // members (clause 11). 1129 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1130 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1131 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1132 Invalid = true; 1133 } 1134 } else if ((*Mem)->isImplicit()) { 1135 // Any implicit members are fine. 1136 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1137 // This is a type that showed up in an 1138 // elaborated-type-specifier inside the anonymous struct or 1139 // union, but which actually declares a type outside of the 1140 // anonymous struct or union. It's okay. 1141 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1142 if (!MemRecord->isAnonymousStructOrUnion() && 1143 MemRecord->getDeclName()) { 1144 // This is a nested type declaration. 1145 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1146 << (int)Record->isUnion(); 1147 Invalid = true; 1148 } 1149 } else { 1150 // We have something that isn't a non-static data 1151 // member. Complain about it. 1152 unsigned DK = diag::err_anonymous_record_bad_member; 1153 if (isa<TypeDecl>(*Mem)) 1154 DK = diag::err_anonymous_record_with_type; 1155 else if (isa<FunctionDecl>(*Mem)) 1156 DK = diag::err_anonymous_record_with_function; 1157 else if (isa<VarDecl>(*Mem)) 1158 DK = diag::err_anonymous_record_with_static; 1159 Diag((*Mem)->getLocation(), DK) 1160 << (int)Record->isUnion(); 1161 Invalid = true; 1162 } 1163 } 1164 } 1165 1166 if (!Record->isUnion() && !Owner->isRecord()) { 1167 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1168 << (int)getLangOptions().CPlusPlus; 1169 Invalid = true; 1170 } 1171 1172 // Create a declaration for this anonymous struct/union. 1173 NamedDecl *Anon = 0; 1174 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1175 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1176 /*IdentifierInfo=*/0, 1177 Context.getTypeDeclType(Record), 1178 /*BitWidth=*/0, /*Mutable=*/false); 1179 Anon->setAccess(AS_public); 1180 if (getLangOptions().CPlusPlus) 1181 FieldCollector->Add(cast<FieldDecl>(Anon)); 1182 } else { 1183 VarDecl::StorageClass SC; 1184 switch (DS.getStorageClassSpec()) { 1185 default: assert(0 && "Unknown storage class!"); 1186 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1187 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1188 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1189 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1190 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1191 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1192 case DeclSpec::SCS_mutable: 1193 // mutable can only appear on non-static class members, so it's always 1194 // an error here 1195 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1196 Invalid = true; 1197 SC = VarDecl::None; 1198 break; 1199 } 1200 1201 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1202 /*IdentifierInfo=*/0, 1203 Context.getTypeDeclType(Record), 1204 SC, DS.getSourceRange().getBegin()); 1205 } 1206 Anon->setImplicit(); 1207 1208 // Add the anonymous struct/union object to the current 1209 // context. We'll be referencing this object when we refer to one of 1210 // its members. 1211 Owner->addDecl(Context, Anon); 1212 1213 // Inject the members of the anonymous struct/union into the owning 1214 // context and into the identifier resolver chain for name lookup 1215 // purposes. 1216 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1217 Invalid = true; 1218 1219 // Mark this as an anonymous struct/union type. Note that we do not 1220 // do this until after we have already checked and injected the 1221 // members of this anonymous struct/union type, because otherwise 1222 // the members could be injected twice: once by DeclContext when it 1223 // builds its lookup table, and once by 1224 // InjectAnonymousStructOrUnionMembers. 1225 Record->setAnonymousStructOrUnion(true); 1226 1227 if (Invalid) 1228 Anon->setInvalidDecl(); 1229 1230 return DeclPtrTy::make(Anon); 1231} 1232 1233 1234/// GetNameForDeclarator - Determine the full declaration name for the 1235/// given Declarator. 1236DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1237 switch (D.getKind()) { 1238 case Declarator::DK_Abstract: 1239 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1240 return DeclarationName(); 1241 1242 case Declarator::DK_Normal: 1243 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1244 return DeclarationName(D.getIdentifier()); 1245 1246 case Declarator::DK_Constructor: { 1247 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1248 Ty = Context.getCanonicalType(Ty); 1249 return Context.DeclarationNames.getCXXConstructorName(Ty); 1250 } 1251 1252 case Declarator::DK_Destructor: { 1253 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1254 Ty = Context.getCanonicalType(Ty); 1255 return Context.DeclarationNames.getCXXDestructorName(Ty); 1256 } 1257 1258 case Declarator::DK_Conversion: { 1259 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1260 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1261 Ty = Context.getCanonicalType(Ty); 1262 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1263 } 1264 1265 case Declarator::DK_Operator: 1266 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1267 return Context.DeclarationNames.getCXXOperatorName( 1268 D.getOverloadedOperator()); 1269 } 1270 1271 assert(false && "Unknown name kind"); 1272 return DeclarationName(); 1273} 1274 1275/// isNearlyMatchingFunction - Determine whether the C++ functions 1276/// Declaration and Definition are "nearly" matching. This heuristic 1277/// is used to improve diagnostics in the case where an out-of-line 1278/// function definition doesn't match any declaration within 1279/// the class or namespace. 1280static bool isNearlyMatchingFunction(ASTContext &Context, 1281 FunctionDecl *Declaration, 1282 FunctionDecl *Definition) { 1283 if (Declaration->param_size() != Definition->param_size()) 1284 return false; 1285 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1286 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1287 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1288 1289 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1290 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1291 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1292 return false; 1293 } 1294 1295 return true; 1296} 1297 1298Sema::DeclPtrTy 1299Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1300 DeclarationName Name = GetNameForDeclarator(D); 1301 1302 // All of these full declarators require an identifier. If it doesn't have 1303 // one, the ParsedFreeStandingDeclSpec action should be used. 1304 if (!Name) { 1305 if (!D.getInvalidType()) // Reject this if we think it is valid. 1306 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1307 diag::err_declarator_need_ident) 1308 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1309 return DeclPtrTy(); 1310 } 1311 1312 // The scope passed in may not be a decl scope. Zip up the scope tree until 1313 // we find one that is. 1314 while ((S->getFlags() & Scope::DeclScope) == 0 || 1315 (S->getFlags() & Scope::TemplateParamScope) != 0) 1316 S = S->getParent(); 1317 1318 DeclContext *DC; 1319 NamedDecl *PrevDecl; 1320 NamedDecl *New; 1321 bool InvalidDecl = false; 1322 1323 QualType R = GetTypeForDeclarator(D, S); 1324 if (R.isNull()) { 1325 InvalidDecl = true; 1326 R = Context.IntTy; 1327 if (IsFunctionDefinition) // int(...) 1328 R = Context.getFunctionType(R, 0, 0, true, 0); 1329 1330 } 1331 1332 // See if this is a redefinition of a variable in the same scope. 1333 if (D.getCXXScopeSpec().isInvalid()) { 1334 DC = CurContext; 1335 PrevDecl = 0; 1336 InvalidDecl = true; 1337 } else if (!D.getCXXScopeSpec().isSet()) { 1338 LookupNameKind NameKind = LookupOrdinaryName; 1339 1340 // If the declaration we're planning to build will be a function 1341 // or object with linkage, then look for another declaration with 1342 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1343 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1344 /* Do nothing*/; 1345 else if (R->isFunctionType()) { 1346 if (CurContext->isFunctionOrMethod()) 1347 NameKind = LookupRedeclarationWithLinkage; 1348 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1349 NameKind = LookupRedeclarationWithLinkage; 1350 1351 DC = CurContext; 1352 PrevDecl = LookupName(S, Name, NameKind, true, 1353 D.getDeclSpec().getStorageClassSpec() != 1354 DeclSpec::SCS_static, 1355 D.getIdentifierLoc()); 1356 } else { // Something like "int foo::x;" 1357 DC = computeDeclContext(D.getCXXScopeSpec()); 1358 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1359 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1360 1361 // C++ 7.3.1.2p2: 1362 // Members (including explicit specializations of templates) of a named 1363 // namespace can also be defined outside that namespace by explicit 1364 // qualification of the name being defined, provided that the entity being 1365 // defined was already declared in the namespace and the definition appears 1366 // after the point of declaration in a namespace that encloses the 1367 // declarations namespace. 1368 // 1369 // Note that we only check the context at this point. We don't yet 1370 // have enough information to make sure that PrevDecl is actually 1371 // the declaration we want to match. For example, given: 1372 // 1373 // class X { 1374 // void f(); 1375 // void f(float); 1376 // }; 1377 // 1378 // void X::f(int) { } // ill-formed 1379 // 1380 // In this case, PrevDecl will point to the overload set 1381 // containing the two f's declared in X, but neither of them 1382 // matches. 1383 1384 // First check whether we named the global scope. 1385 if (isa<TranslationUnitDecl>(DC)) { 1386 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1387 << Name << D.getCXXScopeSpec().getRange(); 1388 } else if (!CurContext->Encloses(DC)) { 1389 // The qualifying scope doesn't enclose the original declaration. 1390 // Emit diagnostic based on current scope. 1391 SourceLocation L = D.getIdentifierLoc(); 1392 SourceRange R = D.getCXXScopeSpec().getRange(); 1393 if (isa<FunctionDecl>(CurContext)) 1394 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1395 else 1396 Diag(L, diag::err_invalid_declarator_scope) 1397 << Name << cast<NamedDecl>(DC) << R; 1398 InvalidDecl = true; 1399 } 1400 } 1401 1402 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1403 // Maybe we will complain about the shadowed template parameter. 1404 InvalidDecl = InvalidDecl 1405 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1406 // Just pretend that we didn't see the previous declaration. 1407 PrevDecl = 0; 1408 } 1409 1410 // In C++, the previous declaration we find might be a tag type 1411 // (class or enum). In this case, the new declaration will hide the 1412 // tag type. Note that this does does not apply if we're declaring a 1413 // typedef (C++ [dcl.typedef]p4). 1414 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1415 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1416 PrevDecl = 0; 1417 1418 bool Redeclaration = false; 1419 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1420 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, 1421 InvalidDecl, Redeclaration); 1422 } else if (R->isFunctionType()) { 1423 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1424 IsFunctionDefinition, InvalidDecl, 1425 Redeclaration); 1426 } else { 1427 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, 1428 InvalidDecl, Redeclaration); 1429 } 1430 1431 if (New == 0) 1432 return DeclPtrTy(); 1433 1434 // If this has an identifier and is not an invalid redeclaration, 1435 // add it to the scope stack. 1436 if (Name && !(Redeclaration && InvalidDecl)) 1437 PushOnScopeChains(New, S); 1438 // If any semantic error occurred, mark the decl as invalid. 1439 if (D.getInvalidType() || InvalidDecl) 1440 New->setInvalidDecl(); 1441 1442 return DeclPtrTy::make(New); 1443} 1444 1445/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1446/// types into constant array types in certain situations which would otherwise 1447/// be errors (for GCC compatibility). 1448static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1449 ASTContext &Context, 1450 bool &SizeIsNegative) { 1451 // This method tries to turn a variable array into a constant 1452 // array even when the size isn't an ICE. This is necessary 1453 // for compatibility with code that depends on gcc's buggy 1454 // constant expression folding, like struct {char x[(int)(char*)2];} 1455 SizeIsNegative = false; 1456 1457 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1458 QualType Pointee = PTy->getPointeeType(); 1459 QualType FixedType = 1460 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1461 if (FixedType.isNull()) return FixedType; 1462 FixedType = Context.getPointerType(FixedType); 1463 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1464 return FixedType; 1465 } 1466 1467 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1468 if (!VLATy) 1469 return QualType(); 1470 // FIXME: We should probably handle this case 1471 if (VLATy->getElementType()->isVariablyModifiedType()) 1472 return QualType(); 1473 1474 Expr::EvalResult EvalResult; 1475 if (!VLATy->getSizeExpr() || 1476 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1477 !EvalResult.Val.isInt()) 1478 return QualType(); 1479 1480 llvm::APSInt &Res = EvalResult.Val.getInt(); 1481 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1482 return Context.getConstantArrayType(VLATy->getElementType(), 1483 Res, ArrayType::Normal, 0); 1484 1485 SizeIsNegative = true; 1486 return QualType(); 1487} 1488 1489/// \brief Register the given locally-scoped external C declaration so 1490/// that it can be found later for redeclarations 1491void 1492Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1493 Scope *S) { 1494 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1495 "Decl is not a locally-scoped decl!"); 1496 // Note that we have a locally-scoped external with this name. 1497 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1498 1499 if (!PrevDecl) 1500 return; 1501 1502 // If there was a previous declaration of this variable, it may be 1503 // in our identifier chain. Update the identifier chain with the new 1504 // declaration. 1505 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1506 // The previous declaration was found on the identifer resolver 1507 // chain, so remove it from its scope. 1508 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1509 S = S->getParent(); 1510 1511 if (S) 1512 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1513 } 1514} 1515 1516/// \brief Diagnose function specifiers on a declaration of an identifier that 1517/// does not identify a function. 1518void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1519 // FIXME: We should probably indicate the identifier in question to avoid 1520 // confusion for constructs like "inline int a(), b;" 1521 if (D.getDeclSpec().isInlineSpecified()) 1522 Diag(D.getDeclSpec().getInlineSpecLoc(), 1523 diag::err_inline_non_function); 1524 1525 if (D.getDeclSpec().isVirtualSpecified()) 1526 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1527 diag::err_virtual_non_function); 1528 1529 if (D.getDeclSpec().isExplicitSpecified()) 1530 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1531 diag::err_explicit_non_function); 1532} 1533 1534NamedDecl* 1535Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1536 QualType R, Decl* PrevDecl, bool& InvalidDecl, 1537 bool &Redeclaration) { 1538 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1539 if (D.getCXXScopeSpec().isSet()) { 1540 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1541 << D.getCXXScopeSpec().getRange(); 1542 InvalidDecl = true; 1543 // Pretend we didn't see the scope specifier. 1544 DC = 0; 1545 } 1546 1547 if (getLangOptions().CPlusPlus) { 1548 // Check that there are no default arguments (C++ only). 1549 CheckExtraCXXDefaultArguments(D); 1550 } 1551 1552 DiagnoseFunctionSpecifiers(D); 1553 1554 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1555 if (!NewTD) return 0; 1556 1557 // Handle attributes prior to checking for duplicates in MergeVarDecl 1558 ProcessDeclAttributes(NewTD, D); 1559 // Merge the decl with the existing one if appropriate. If the decl is 1560 // in an outer scope, it isn't the same thing. 1561 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1562 Redeclaration = true; 1563 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1564 InvalidDecl = true; 1565 } 1566 1567 if (S->getFnParent() == 0) { 1568 QualType T = NewTD->getUnderlyingType(); 1569 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1570 // then it shall have block scope. 1571 if (T->isVariablyModifiedType()) { 1572 bool SizeIsNegative; 1573 QualType FixedTy = 1574 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1575 if (!FixedTy.isNull()) { 1576 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1577 NewTD->setUnderlyingType(FixedTy); 1578 } else { 1579 if (SizeIsNegative) 1580 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1581 else if (T->isVariableArrayType()) 1582 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1583 else 1584 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1585 InvalidDecl = true; 1586 } 1587 } 1588 } 1589 return NewTD; 1590} 1591 1592/// \brief Determines whether the given declaration is an out-of-scope 1593/// previous declaration. 1594/// 1595/// This routine should be invoked when name lookup has found a 1596/// previous declaration (PrevDecl) that is not in the scope where a 1597/// new declaration by the same name is being introduced. If the new 1598/// declaration occurs in a local scope, previous declarations with 1599/// linkage may still be considered previous declarations (C99 1600/// 6.2.2p4-5, C++ [basic.link]p6). 1601/// 1602/// \param PrevDecl the previous declaration found by name 1603/// lookup 1604/// 1605/// \param DC the context in which the new declaration is being 1606/// declared. 1607/// 1608/// \returns true if PrevDecl is an out-of-scope previous declaration 1609/// for a new delcaration with the same name. 1610static bool 1611isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1612 ASTContext &Context) { 1613 if (!PrevDecl) 1614 return 0; 1615 1616 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1617 // case we need to check each of the overloaded functions. 1618 if (!PrevDecl->hasLinkage()) 1619 return false; 1620 1621 if (Context.getLangOptions().CPlusPlus) { 1622 // C++ [basic.link]p6: 1623 // If there is a visible declaration of an entity with linkage 1624 // having the same name and type, ignoring entities declared 1625 // outside the innermost enclosing namespace scope, the block 1626 // scope declaration declares that same entity and receives the 1627 // linkage of the previous declaration. 1628 DeclContext *OuterContext = DC->getLookupContext(); 1629 if (!OuterContext->isFunctionOrMethod()) 1630 // This rule only applies to block-scope declarations. 1631 return false; 1632 else { 1633 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1634 if (PrevOuterContext->isRecord()) 1635 // We found a member function: ignore it. 1636 return false; 1637 else { 1638 // Find the innermost enclosing namespace for the new and 1639 // previous declarations. 1640 while (!OuterContext->isFileContext()) 1641 OuterContext = OuterContext->getParent(); 1642 while (!PrevOuterContext->isFileContext()) 1643 PrevOuterContext = PrevOuterContext->getParent(); 1644 1645 // The previous declaration is in a different namespace, so it 1646 // isn't the same function. 1647 if (OuterContext->getPrimaryContext() != 1648 PrevOuterContext->getPrimaryContext()) 1649 return false; 1650 } 1651 } 1652 } 1653 1654 return true; 1655} 1656 1657NamedDecl* 1658Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1659 QualType R,NamedDecl* PrevDecl, bool& InvalidDecl, 1660 bool &Redeclaration) { 1661 DeclarationName Name = GetNameForDeclarator(D); 1662 1663 // Check that there are no default arguments (C++ only). 1664 if (getLangOptions().CPlusPlus) 1665 CheckExtraCXXDefaultArguments(D); 1666 1667 VarDecl *NewVD; 1668 VarDecl::StorageClass SC; 1669 switch (D.getDeclSpec().getStorageClassSpec()) { 1670 default: assert(0 && "Unknown storage class!"); 1671 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1672 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1673 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1674 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1675 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1676 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1677 case DeclSpec::SCS_mutable: 1678 // mutable can only appear on non-static class members, so it's always 1679 // an error here 1680 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1681 InvalidDecl = true; 1682 SC = VarDecl::None; 1683 break; 1684 } 1685 1686 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1687 if (!II) { 1688 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1689 << Name.getAsString(); 1690 return 0; 1691 } 1692 1693 DiagnoseFunctionSpecifiers(D); 1694 1695 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1696 if (!DC->isRecord() && S->getFnParent() == 0) { 1697 // C99 6.9p2: The storage-class specifiers auto and register shall not 1698 // appear in the declaration specifiers in an external declaration. 1699 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1700 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1701 InvalidDecl = true; 1702 } 1703 } 1704 if (DC->isRecord() && !CurContext->isRecord()) { 1705 // This is an out-of-line definition of a static data member. 1706 if (SC == VarDecl::Static) { 1707 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1708 diag::err_static_out_of_line) 1709 << CodeModificationHint::CreateRemoval( 1710 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1711 } else if (SC == VarDecl::None) 1712 SC = VarDecl::Static; 1713 } 1714 1715 // The variable can not 1716 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1717 II, R, SC, 1718 // FIXME: Move to DeclGroup... 1719 D.getDeclSpec().getSourceRange().getBegin()); 1720 NewVD->setThreadSpecified(ThreadSpecified); 1721 1722 // Set the lexical context. If the declarator has a C++ scope specifier, the 1723 // lexical context will be different from the semantic context. 1724 NewVD->setLexicalDeclContext(CurContext); 1725 1726 // Handle attributes prior to checking for duplicates in MergeVarDecl 1727 ProcessDeclAttributes(NewVD, D); 1728 1729 // Handle GNU asm-label extension (encoded as an attribute). 1730 if (Expr *E = (Expr*) D.getAsmLabel()) { 1731 // The parser guarantees this is a string. 1732 StringLiteral *SE = cast<StringLiteral>(E); 1733 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1734 SE->getByteLength()))); 1735 } 1736 1737 // If name lookup finds a previous declaration that is not in the 1738 // same scope as the new declaration, this may still be an 1739 // acceptable redeclaration. 1740 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1741 !(NewVD->hasLinkage() && 1742 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1743 PrevDecl = 0; 1744 1745 // Merge the decl with the existing one if appropriate. 1746 if (PrevDecl) { 1747 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1748 // The user tried to define a non-static data member 1749 // out-of-line (C++ [dcl.meaning]p1). 1750 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1751 << D.getCXXScopeSpec().getRange(); 1752 PrevDecl = 0; 1753 InvalidDecl = true; 1754 } 1755 } else if (D.getCXXScopeSpec().isSet()) { 1756 // No previous declaration in the qualifying scope. 1757 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1758 << Name << D.getCXXScopeSpec().getRange(); 1759 InvalidDecl = true; 1760 } 1761 1762 if (CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration)) 1763 InvalidDecl = true; 1764 1765 // If this is a locally-scoped extern C variable, update the map of 1766 // such variables. 1767 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1768 !InvalidDecl) 1769 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1770 1771 return NewVD; 1772} 1773 1774/// \brief Perform semantic checking on a newly-created variable 1775/// declaration. 1776/// 1777/// This routine performs all of the type-checking required for a 1778/// variable declaration once it has been build. It is used both to 1779/// check variables after they have been parsed and their declarators 1780/// have been translated into a declaration, and to check 1781/// 1782/// \returns true if an error was encountered, false otherwise. 1783bool Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1784 bool &Redeclaration) { 1785 bool Invalid = false; 1786 1787 QualType T = NewVD->getType(); 1788 1789 if (T->isObjCInterfaceType()) { 1790 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1791 Invalid = true; 1792 } 1793 1794 // The variable can not have an abstract class type. 1795 if (RequireNonAbstractType(NewVD->getLocation(), T, 1796 diag::err_abstract_type_in_decl, 1797 AbstractVariableType)) 1798 Invalid = true; 1799 1800 // Emit an error if an address space was applied to decl with local storage. 1801 // This includes arrays of objects with address space qualifiers, but not 1802 // automatic variables that point to other address spaces. 1803 // ISO/IEC TR 18037 S5.1.2 1804 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1805 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1806 Invalid = true; 1807 } 1808 1809 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1810 && !NewVD->hasAttr<BlocksAttr>()) 1811 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1812 1813 bool isIllegalVLA = T->isVariableArrayType() && NewVD->hasGlobalStorage(); 1814 bool isIllegalVM = T->isVariablyModifiedType() && NewVD->hasLinkage(); 1815 if (isIllegalVLA || isIllegalVM) { 1816 bool SizeIsNegative; 1817 QualType FixedTy = 1818 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1819 if (!FixedTy.isNull()) { 1820 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1821 NewVD->setType(FixedTy); 1822 } else if (T->isVariableArrayType()) { 1823 Invalid = true; 1824 1825 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1826 // FIXME: This won't give the correct result for 1827 // int a[10][n]; 1828 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1829 1830 if (NewVD->isFileVarDecl()) 1831 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1832 << SizeRange; 1833 else if (NewVD->getStorageClass() == VarDecl::Static) 1834 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1835 << SizeRange; 1836 else 1837 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1838 << SizeRange; 1839 } else { 1840 Invalid = true; 1841 1842 if (NewVD->isFileVarDecl()) 1843 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1844 else 1845 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1846 } 1847 } 1848 1849 if (!PrevDecl && NewVD->isExternC(Context)) { 1850 // Since we did not find anything by this name and we're declaring 1851 // an extern "C" variable, look for a non-visible extern "C" 1852 // declaration with the same name. 1853 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1854 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1855 if (Pos != LocallyScopedExternalDecls.end()) 1856 PrevDecl = Pos->second; 1857 } 1858 1859 if (!Invalid && T->isVoidType() && !NewVD->hasExternalStorage()) { 1860 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1861 << T; 1862 Invalid = true; 1863 } 1864 1865 if (PrevDecl) { 1866 Redeclaration = true; 1867 if (MergeVarDecl(NewVD, PrevDecl)) 1868 Invalid = true; 1869 } 1870 1871 return NewVD->isInvalidDecl() || Invalid; 1872} 1873 1874NamedDecl* 1875Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1876 QualType R, NamedDecl* PrevDecl, 1877 bool IsFunctionDefinition, 1878 bool& InvalidDecl, bool &Redeclaration) { 1879 assert(R.getTypePtr()->isFunctionType()); 1880 1881 DeclarationName Name = GetNameForDeclarator(D); 1882 FunctionDecl::StorageClass SC = FunctionDecl::None; 1883 switch (D.getDeclSpec().getStorageClassSpec()) { 1884 default: assert(0 && "Unknown storage class!"); 1885 case DeclSpec::SCS_auto: 1886 case DeclSpec::SCS_register: 1887 case DeclSpec::SCS_mutable: 1888 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1889 diag::err_typecheck_sclass_func); 1890 InvalidDecl = true; 1891 break; 1892 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1893 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1894 case DeclSpec::SCS_static: { 1895 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1896 // C99 6.7.1p5: 1897 // The declaration of an identifier for a function that has 1898 // block scope shall have no explicit storage-class specifier 1899 // other than extern 1900 // See also (C++ [dcl.stc]p4). 1901 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1902 diag::err_static_block_func); 1903 SC = FunctionDecl::None; 1904 } else 1905 SC = FunctionDecl::Static; 1906 break; 1907 } 1908 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1909 } 1910 1911 bool isInline = D.getDeclSpec().isInlineSpecified(); 1912 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1913 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1914 1915 // Check that the return type is not an abstract class type. 1916 // For record types, this is done by the AbstractClassUsageDiagnoser once 1917 // the class has been completely parsed. 1918 if (!DC->isRecord() && 1919 RequireNonAbstractType(D.getIdentifierLoc(), 1920 R->getAsFunctionType()->getResultType(), 1921 diag::err_abstract_type_in_decl, 1922 AbstractReturnType)) 1923 InvalidDecl = true; 1924 1925 // Do not allow returning a objc interface by-value. 1926 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1927 Diag(D.getIdentifierLoc(), 1928 diag::err_object_cannot_be_passed_returned_by_value) << 0 1929 << R->getAsFunctionType()->getResultType(); 1930 InvalidDecl = true; 1931 } 1932 1933 bool isVirtualOkay = false; 1934 FunctionDecl *NewFD; 1935 if (D.getKind() == Declarator::DK_Constructor) { 1936 // This is a C++ constructor declaration. 1937 assert(DC->isRecord() && 1938 "Constructors can only be declared in a member context"); 1939 1940 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1941 1942 // Create the new declaration 1943 NewFD = CXXConstructorDecl::Create(Context, 1944 cast<CXXRecordDecl>(DC), 1945 D.getIdentifierLoc(), Name, R, 1946 isExplicit, isInline, 1947 /*isImplicitlyDeclared=*/false); 1948 1949 if (InvalidDecl) 1950 NewFD->setInvalidDecl(); 1951 } else if (D.getKind() == Declarator::DK_Destructor) { 1952 // This is a C++ destructor declaration. 1953 if (DC->isRecord()) { 1954 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1955 1956 NewFD = CXXDestructorDecl::Create(Context, 1957 cast<CXXRecordDecl>(DC), 1958 D.getIdentifierLoc(), Name, R, 1959 isInline, 1960 /*isImplicitlyDeclared=*/false); 1961 1962 if (InvalidDecl) 1963 NewFD->setInvalidDecl(); 1964 1965 isVirtualOkay = true; 1966 } else { 1967 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1968 1969 // Create a FunctionDecl to satisfy the function definition parsing 1970 // code path. 1971 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1972 Name, R, SC, isInline, 1973 /*hasPrototype=*/true, 1974 // FIXME: Move to DeclGroup... 1975 D.getDeclSpec().getSourceRange().getBegin()); 1976 InvalidDecl = true; 1977 NewFD->setInvalidDecl(); 1978 } 1979 } else if (D.getKind() == Declarator::DK_Conversion) { 1980 if (!DC->isRecord()) { 1981 Diag(D.getIdentifierLoc(), 1982 diag::err_conv_function_not_member); 1983 return 0; 1984 } else { 1985 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1986 1987 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1988 D.getIdentifierLoc(), Name, R, 1989 isInline, isExplicit); 1990 1991 if (InvalidDecl) 1992 NewFD->setInvalidDecl(); 1993 1994 isVirtualOkay = true; 1995 } 1996 } else if (DC->isRecord()) { 1997 // This is a C++ method declaration. 1998 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1999 D.getIdentifierLoc(), Name, R, 2000 (SC == FunctionDecl::Static), isInline); 2001 2002 isVirtualOkay = (SC != FunctionDecl::Static); 2003 } else { 2004 // Determine whether the function was written with a 2005 // prototype. This true when: 2006 // - we're in C++ (where every function has a prototype), 2007 // - there is a prototype in the declarator, or 2008 // - the type R of the function is some kind of typedef or other reference 2009 // to a type name (which eventually refers to a function type). 2010 bool HasPrototype = 2011 getLangOptions().CPlusPlus || 2012 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2013 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2014 2015 NewFD = FunctionDecl::Create(Context, DC, 2016 D.getIdentifierLoc(), 2017 Name, R, SC, isInline, HasPrototype, 2018 // FIXME: Move to DeclGroup... 2019 D.getDeclSpec().getSourceRange().getBegin()); 2020 } 2021 2022 // Set the lexical context. If the declarator has a C++ 2023 // scope specifier, the lexical context will be different 2024 // from the semantic context. 2025 NewFD->setLexicalDeclContext(CurContext); 2026 2027 // C++ [dcl.fct.spec]p5: 2028 // The virtual specifier shall only be used in declarations of 2029 // nonstatic class member functions that appear within a 2030 // member-specification of a class declaration; see 10.3. 2031 // 2032 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2033 // function is also virtual if it overrides an already virtual 2034 // function. This is important to do here because it's part of the 2035 // declaration. 2036 if (isVirtual && !InvalidDecl) { 2037 if (!isVirtualOkay) { 2038 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2039 diag::err_virtual_non_function); 2040 } else if (!CurContext->isRecord()) { 2041 // 'virtual' was specified outside of the class. 2042 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2043 << CodeModificationHint::CreateRemoval( 2044 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2045 } else { 2046 // Okay: Add virtual to the method. 2047 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2048 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2049 CurClass->setAggregate(false); 2050 CurClass->setPOD(false); 2051 CurClass->setPolymorphic(true); 2052 CurClass->setHasTrivialConstructor(false); 2053 } 2054 } 2055 2056 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2057 !CurContext->isRecord()) { 2058 // C++ [class.static]p1: 2059 // A data or function member of a class may be declared static 2060 // in a class definition, in which case it is a static member of 2061 // the class. 2062 2063 // Complain about the 'static' specifier if it's on an out-of-line 2064 // member function definition. 2065 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2066 diag::err_static_out_of_line) 2067 << CodeModificationHint::CreateRemoval( 2068 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2069 } 2070 2071 // Handle GNU asm-label extension (encoded as an attribute). 2072 if (Expr *E = (Expr*) D.getAsmLabel()) { 2073 // The parser guarantees this is a string. 2074 StringLiteral *SE = cast<StringLiteral>(E); 2075 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2076 SE->getByteLength()))); 2077 } 2078 2079 // Copy the parameter declarations from the declarator D to 2080 // the function declaration NewFD, if they are available. 2081 if (D.getNumTypeObjects() > 0) { 2082 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2083 2084 // Create Decl objects for each parameter, adding them to the 2085 // FunctionDecl. 2086 llvm::SmallVector<ParmVarDecl*, 16> Params; 2087 2088 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2089 // function that takes no arguments, not a function that takes a 2090 // single void argument. 2091 // We let through "const void" here because Sema::GetTypeForDeclarator 2092 // already checks for that case. 2093 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2094 FTI.ArgInfo[0].Param && 2095 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2096 // empty arg list, don't push any params. 2097 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2098 2099 // In C++, the empty parameter-type-list must be spelled "void"; a 2100 // typedef of void is not permitted. 2101 if (getLangOptions().CPlusPlus && 2102 Param->getType().getUnqualifiedType() != Context.VoidTy) { 2103 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2104 } 2105 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2106 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2107 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2108 } 2109 2110 NewFD->setParams(Context, &Params[0], Params.size()); 2111 } else if (R->getAsTypedefType()) { 2112 // When we're declaring a function with a typedef, as in the 2113 // following example, we'll need to synthesize (unnamed) 2114 // parameters for use in the declaration. 2115 // 2116 // @code 2117 // typedef void fn(int); 2118 // fn f; 2119 // @endcode 2120 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 2121 if (!FT) { 2122 // This is a typedef of a function with no prototype, so we 2123 // don't need to do anything. 2124 } else if ((FT->getNumArgs() == 0) || 2125 (FT->getNumArgs() == 1 && !FT->isVariadic() && 2126 FT->getArgType(0)->isVoidType())) { 2127 // This is a zero-argument function. We don't need to do anything. 2128 } else { 2129 // Synthesize a parameter for each argument type. 2130 llvm::SmallVector<ParmVarDecl*, 16> Params; 2131 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 2132 ArgType != FT->arg_type_end(); ++ArgType) { 2133 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2134 SourceLocation(), 0, 2135 *ArgType, VarDecl::None, 2136 0); 2137 Param->setImplicit(); 2138 Params.push_back(Param); 2139 } 2140 2141 NewFD->setParams(Context, &Params[0], Params.size()); 2142 } 2143 } 2144 2145 // If name lookup finds a previous declaration that is not in the 2146 // same scope as the new declaration, this may still be an 2147 // acceptable redeclaration. 2148 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2149 !(NewFD->hasLinkage() && 2150 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2151 PrevDecl = 0; 2152 2153 // Perform semantic checking on the function declaration. 2154 bool OverloadableAttrRequired = false; // FIXME: HACK! 2155 if (CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2156 /*FIXME:*/OverloadableAttrRequired)) 2157 InvalidDecl = true; 2158 2159 if (D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2160 // An out-of-line member function declaration must also be a 2161 // definition (C++ [dcl.meaning]p1). 2162 if (!IsFunctionDefinition) { 2163 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2164 << D.getCXXScopeSpec().getRange(); 2165 InvalidDecl = true; 2166 } else if (!Redeclaration) { 2167 // The user tried to provide an out-of-line definition for a 2168 // function that is a member of a class or namespace, but there 2169 // was no such member function declared (C++ [class.mfct]p2, 2170 // C++ [namespace.memdef]p2). For example: 2171 // 2172 // class X { 2173 // void f() const; 2174 // }; 2175 // 2176 // void X::f() { } // ill-formed 2177 // 2178 // Complain about this problem, and attempt to suggest close 2179 // matches (e.g., those that differ only in cv-qualifiers and 2180 // whether the parameter types are references). 2181 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2182 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2183 InvalidDecl = true; 2184 2185 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2186 true); 2187 assert(!Prev.isAmbiguous() && 2188 "Cannot have an ambiguity in previous-declaration lookup"); 2189 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2190 Func != FuncEnd; ++Func) { 2191 if (isa<FunctionDecl>(*Func) && 2192 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2193 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2194 } 2195 2196 PrevDecl = 0; 2197 } 2198 } 2199 2200 // Handle attributes. We need to have merged decls when handling attributes 2201 // (for example to check for conflicts, etc). 2202 // FIXME: This needs to happen before we merge declarations. Then, 2203 // let attribute merging cope with attribute conflicts. 2204 ProcessDeclAttributes(NewFD, D); 2205 AddKnownFunctionAttributes(NewFD); 2206 2207 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2208 // If a function name is overloadable in C, then every function 2209 // with that name must be marked "overloadable". 2210 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2211 << Redeclaration << NewFD; 2212 if (PrevDecl) 2213 Diag(PrevDecl->getLocation(), 2214 diag::note_attribute_overloadable_prev_overload); 2215 NewFD->addAttr(::new (Context) OverloadableAttr()); 2216 } 2217 2218 // If this is a locally-scoped extern C function, update the 2219 // map of such names. 2220 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2221 && !InvalidDecl) 2222 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2223 2224 return NewFD; 2225} 2226 2227/// \brief Perform semantic checking of a new function declaration. 2228/// 2229/// Performs semantic analysis of the new function declaration 2230/// NewFD. This routine performs all semantic checking that does not 2231/// require the actual declarator involved in the declaration, and is 2232/// used both for the declaration of functions as they are parsed 2233/// (called via ActOnDeclarator) and for the declaration of functions 2234/// that have been instantiated via C++ template instantiation (called 2235/// via InstantiateDecl). 2236/// 2237/// \returns true if there was an error, false otherwise. 2238bool Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2239 bool &Redeclaration, 2240 bool &OverloadableAttrRequired) { 2241 bool InvalidDecl = false; 2242 2243 // Semantic checking for this function declaration (in isolation). 2244 if (getLangOptions().CPlusPlus) { 2245 // C++-specific checks. 2246 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 2247 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 2248 else if (isa<CXXDestructorDecl>(NewFD)) { 2249 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2250 Record->setUserDeclaredDestructor(true); 2251 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2252 // user-defined destructor. 2253 Record->setPOD(false); 2254 2255 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2256 // declared destructor. 2257 Record->setHasTrivialDestructor(false); 2258 } else if (CXXConversionDecl *Conversion 2259 = dyn_cast<CXXConversionDecl>(NewFD)) 2260 ActOnConversionDeclarator(Conversion); 2261 2262 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2263 if (NewFD->isOverloadedOperator() && 2264 CheckOverloadedOperatorDeclaration(NewFD)) 2265 InvalidDecl = true; 2266 } 2267 2268 // Check for a previous declaration of this name. 2269 if (!PrevDecl && NewFD->isExternC(Context)) { 2270 // Since we did not find anything by this name and we're declaring 2271 // an extern "C" function, look for a non-visible extern "C" 2272 // declaration with the same name. 2273 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2274 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2275 if (Pos != LocallyScopedExternalDecls.end()) 2276 PrevDecl = Pos->second; 2277 } 2278 2279 // Merge or overload the declaration with an existing declaration of 2280 // the same name, if appropriate. 2281 if (PrevDecl) { 2282 // Determine whether NewFD is an overload of PrevDecl or 2283 // a declaration that requires merging. If it's an overload, 2284 // there's no more work to do here; we'll just add the new 2285 // function to the scope. 2286 OverloadedFunctionDecl::function_iterator MatchedDecl; 2287 2288 if (!getLangOptions().CPlusPlus && 2289 AllowOverloadingOfFunction(PrevDecl, Context)) { 2290 OverloadableAttrRequired = true; 2291 2292 // Functions marked "overloadable" must have a prototype (that 2293 // we can't get through declaration merging). 2294 if (!NewFD->getType()->getAsFunctionProtoType()) { 2295 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2296 << NewFD; 2297 InvalidDecl = true; 2298 Redeclaration = true; 2299 2300 // Turn this into a variadic function with no parameters. 2301 QualType R = Context.getFunctionType( 2302 NewFD->getType()->getAsFunctionType()->getResultType(), 2303 0, 0, true, 0); 2304 NewFD->setType(R); 2305 } 2306 } 2307 2308 if (PrevDecl && 2309 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2310 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2311 Redeclaration = true; 2312 Decl *OldDecl = PrevDecl; 2313 2314 // If PrevDecl was an overloaded function, extract the 2315 // FunctionDecl that matched. 2316 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2317 OldDecl = *MatchedDecl; 2318 2319 // NewFD and OldDecl represent declarations that need to be 2320 // merged. 2321 if (MergeFunctionDecl(NewFD, OldDecl)) 2322 InvalidDecl = true; 2323 2324 if (!InvalidDecl) 2325 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2326 } 2327 } 2328 2329 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) { 2330 // In C++, check default arguments now that we have merged decls. Unless 2331 // the lexical context is the class, because in this case this is done 2332 // during delayed parsing anyway. 2333 CheckCXXDefaultArguments(NewFD); 2334 } 2335 2336 return InvalidDecl || NewFD->isInvalidDecl(); 2337} 2338 2339bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2340 // FIXME: Need strict checking. In C89, we need to check for 2341 // any assignment, increment, decrement, function-calls, or 2342 // commas outside of a sizeof. In C99, it's the same list, 2343 // except that the aforementioned are allowed in unevaluated 2344 // expressions. Everything else falls under the 2345 // "may accept other forms of constant expressions" exception. 2346 // (We never end up here for C++, so the constant expression 2347 // rules there don't matter.) 2348 if (Init->isConstantInitializer(Context)) 2349 return false; 2350 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2351 << Init->getSourceRange(); 2352 return true; 2353} 2354 2355void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2356 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2357} 2358 2359/// AddInitializerToDecl - Adds the initializer Init to the 2360/// declaration dcl. If DirectInit is true, this is C++ direct 2361/// initialization rather than copy initialization. 2362void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2363 Decl *RealDecl = dcl.getAs<Decl>(); 2364 // If there is no declaration, there was an error parsing it. Just ignore 2365 // the initializer. 2366 if (RealDecl == 0) 2367 return; 2368 2369 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2370 // With declarators parsed the way they are, the parser cannot 2371 // distinguish between a normal initializer and a pure-specifier. 2372 // Thus this grotesque test. 2373 IntegerLiteral *IL; 2374 Expr *Init = static_cast<Expr *>(init.get()); 2375 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2376 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2377 if (Method->isVirtual()) { 2378 Method->setPure(); 2379 2380 // A class is abstract if at least one function is pure virtual. 2381 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2382 } else if (!Method->isInvalidDecl()) { 2383 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2384 << Method->getDeclName() << Init->getSourceRange(); 2385 Method->setInvalidDecl(); 2386 } 2387 } else { 2388 Diag(Method->getLocation(), diag::err_member_function_initialization) 2389 << Method->getDeclName() << Init->getSourceRange(); 2390 Method->setInvalidDecl(); 2391 } 2392 return; 2393 } 2394 2395 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2396 if (!VDecl) { 2397 if (getLangOptions().CPlusPlus && 2398 RealDecl->getLexicalDeclContext()->isRecord() && 2399 isa<NamedDecl>(RealDecl)) 2400 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2401 << cast<NamedDecl>(RealDecl)->getDeclName(); 2402 else 2403 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2404 RealDecl->setInvalidDecl(); 2405 return; 2406 } 2407 2408 if (!VDecl->getType()->isArrayType() && 2409 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2410 diag::err_typecheck_decl_incomplete_type)) { 2411 RealDecl->setInvalidDecl(); 2412 return; 2413 } 2414 2415 const VarDecl *Def = 0; 2416 if (VDecl->getDefinition(Def)) { 2417 Diag(VDecl->getLocation(), diag::err_redefinition) 2418 << VDecl->getDeclName(); 2419 Diag(Def->getLocation(), diag::note_previous_definition); 2420 VDecl->setInvalidDecl(); 2421 return; 2422 } 2423 2424 // Take ownership of the expression, now that we're sure we have somewhere 2425 // to put it. 2426 Expr *Init = static_cast<Expr *>(init.release()); 2427 assert(Init && "missing initializer"); 2428 2429 // Get the decls type and save a reference for later, since 2430 // CheckInitializerTypes may change it. 2431 QualType DclT = VDecl->getType(), SavT = DclT; 2432 if (VDecl->isBlockVarDecl()) { 2433 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2434 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2435 VDecl->setInvalidDecl(); 2436 } else if (!VDecl->isInvalidDecl()) { 2437 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2438 VDecl->getDeclName(), DirectInit)) 2439 VDecl->setInvalidDecl(); 2440 2441 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2442 // Don't check invalid declarations to avoid emitting useless diagnostics. 2443 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2444 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2445 CheckForConstantInitializer(Init, DclT); 2446 } 2447 } 2448 } else if (VDecl->isStaticDataMember() && 2449 VDecl->getLexicalDeclContext()->isRecord()) { 2450 // This is an in-class initialization for a static data member, e.g., 2451 // 2452 // struct S { 2453 // static const int value = 17; 2454 // }; 2455 2456 // Attach the initializer 2457 VDecl->setInit(Init); 2458 2459 // C++ [class.mem]p4: 2460 // A member-declarator can contain a constant-initializer only 2461 // if it declares a static member (9.4) of const integral or 2462 // const enumeration type, see 9.4.2. 2463 QualType T = VDecl->getType(); 2464 if (!T->isDependentType() && 2465 (!Context.getCanonicalType(T).isConstQualified() || 2466 !T->isIntegralType())) { 2467 Diag(VDecl->getLocation(), diag::err_member_initialization) 2468 << VDecl->getDeclName() << Init->getSourceRange(); 2469 VDecl->setInvalidDecl(); 2470 } else { 2471 // C++ [class.static.data]p4: 2472 // If a static data member is of const integral or const 2473 // enumeration type, its declaration in the class definition 2474 // can specify a constant-initializer which shall be an 2475 // integral constant expression (5.19). 2476 if (!Init->isTypeDependent() && 2477 !Init->getType()->isIntegralType()) { 2478 // We have a non-dependent, non-integral or enumeration type. 2479 Diag(Init->getSourceRange().getBegin(), 2480 diag::err_in_class_initializer_non_integral_type) 2481 << Init->getType() << Init->getSourceRange(); 2482 VDecl->setInvalidDecl(); 2483 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2484 // Check whether the expression is a constant expression. 2485 llvm::APSInt Value; 2486 SourceLocation Loc; 2487 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2488 Diag(Loc, diag::err_in_class_initializer_non_constant) 2489 << Init->getSourceRange(); 2490 VDecl->setInvalidDecl(); 2491 } else if (!VDecl->getType()->isDependentType()) 2492 ImpCastExprToType(Init, VDecl->getType()); 2493 } 2494 } 2495 } else if (VDecl->isFileVarDecl()) { 2496 if (VDecl->getStorageClass() == VarDecl::Extern) 2497 Diag(VDecl->getLocation(), diag::warn_extern_init); 2498 if (!VDecl->isInvalidDecl()) 2499 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2500 VDecl->getDeclName(), DirectInit)) 2501 VDecl->setInvalidDecl(); 2502 2503 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2504 // Don't check invalid declarations to avoid emitting useless diagnostics. 2505 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2506 // C99 6.7.8p4. All file scoped initializers need to be constant. 2507 CheckForConstantInitializer(Init, DclT); 2508 } 2509 } 2510 // If the type changed, it means we had an incomplete type that was 2511 // completed by the initializer. For example: 2512 // int ary[] = { 1, 3, 5 }; 2513 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2514 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2515 VDecl->setType(DclT); 2516 Init->setType(DclT); 2517 } 2518 2519 // Attach the initializer to the decl. 2520 VDecl->setInit(Init); 2521 return; 2522} 2523 2524void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2525 Decl *RealDecl = dcl.getAs<Decl>(); 2526 2527 // If there is no declaration, there was an error parsing it. Just ignore it. 2528 if (RealDecl == 0) 2529 return; 2530 2531 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2532 QualType Type = Var->getType(); 2533 // C++ [dcl.init.ref]p3: 2534 // The initializer can be omitted for a reference only in a 2535 // parameter declaration (8.3.5), in the declaration of a 2536 // function return type, in the declaration of a class member 2537 // within its class declaration (9.2), and where the extern 2538 // specifier is explicitly used. 2539 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2540 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2541 << Var->getDeclName() 2542 << SourceRange(Var->getLocation(), Var->getLocation()); 2543 Var->setInvalidDecl(); 2544 return; 2545 } 2546 2547 // C++ [dcl.init]p9: 2548 // 2549 // If no initializer is specified for an object, and the object 2550 // is of (possibly cv-qualified) non-POD class type (or array 2551 // thereof), the object shall be default-initialized; if the 2552 // object is of const-qualified type, the underlying class type 2553 // shall have a user-declared default constructor. 2554 if (getLangOptions().CPlusPlus) { 2555 QualType InitType = Type; 2556 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2557 InitType = Array->getElementType(); 2558 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2559 CXXRecordDecl *RD = 2560 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2561 CXXConstructorDecl *Constructor = 0; 2562 if (!RequireCompleteType(Var->getLocation(), InitType, 2563 diag::err_invalid_incomplete_type_use)) 2564 Constructor 2565 = PerformInitializationByConstructor(InitType, 0, 0, 2566 Var->getLocation(), 2567 SourceRange(Var->getLocation(), 2568 Var->getLocation()), 2569 Var->getDeclName(), 2570 IK_Default); 2571 if (!Constructor) 2572 Var->setInvalidDecl(); 2573 else if (!RD->hasTrivialConstructor()) 2574 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2575 } 2576 } 2577 2578#if 0 2579 // FIXME: Temporarily disabled because we are not properly parsing 2580 // linkage specifications on declarations, e.g., 2581 // 2582 // extern "C" const CGPoint CGPointerZero; 2583 // 2584 // C++ [dcl.init]p9: 2585 // 2586 // If no initializer is specified for an object, and the 2587 // object is of (possibly cv-qualified) non-POD class type (or 2588 // array thereof), the object shall be default-initialized; if 2589 // the object is of const-qualified type, the underlying class 2590 // type shall have a user-declared default 2591 // constructor. Otherwise, if no initializer is specified for 2592 // an object, the object and its subobjects, if any, have an 2593 // indeterminate initial value; if the object or any of its 2594 // subobjects are of const-qualified type, the program is 2595 // ill-formed. 2596 // 2597 // This isn't technically an error in C, so we don't diagnose it. 2598 // 2599 // FIXME: Actually perform the POD/user-defined default 2600 // constructor check. 2601 if (getLangOptions().CPlusPlus && 2602 Context.getCanonicalType(Type).isConstQualified() && 2603 !Var->hasExternalStorage()) 2604 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2605 << Var->getName() 2606 << SourceRange(Var->getLocation(), Var->getLocation()); 2607#endif 2608 } 2609} 2610 2611Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2612 unsigned NumDecls) { 2613 llvm::SmallVector<Decl*, 8> Decls; 2614 2615 for (unsigned i = 0; i != NumDecls; ++i) 2616 if (Decl *D = Group[i].getAs<Decl>()) 2617 Decls.push_back(D); 2618 2619 // Perform semantic analysis that depends on having fully processed both 2620 // the declarator and initializer. 2621 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2622 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2623 if (!IDecl) 2624 continue; 2625 QualType T = IDecl->getType(); 2626 2627 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2628 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2629 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2630 if (!IDecl->isInvalidDecl() && 2631 RequireCompleteType(IDecl->getLocation(), T, 2632 diag::err_typecheck_decl_incomplete_type)) 2633 IDecl->setInvalidDecl(); 2634 } 2635 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2636 // object that has file scope without an initializer, and without a 2637 // storage-class specifier or with the storage-class specifier "static", 2638 // constitutes a tentative definition. Note: A tentative definition with 2639 // external linkage is valid (C99 6.2.2p5). 2640 if (IDecl->isTentativeDefinition(Context)) { 2641 QualType CheckType = T; 2642 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2643 2644 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2645 if (ArrayT) { 2646 CheckType = ArrayT->getElementType(); 2647 DiagID = diag::err_illegal_decl_array_incomplete_type; 2648 } 2649 2650 if (IDecl->isInvalidDecl()) { 2651 // Do nothing with invalid declarations 2652 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2653 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2654 // C99 6.9.2p3: If the declaration of an identifier for an object is 2655 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2656 // declared type shall not be an incomplete type. 2657 IDecl->setInvalidDecl(); 2658 } 2659 } 2660 } 2661 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2662 &Decls[0], Decls.size())); 2663} 2664 2665 2666/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2667/// to introduce parameters into function prototype scope. 2668Sema::DeclPtrTy 2669Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2670 const DeclSpec &DS = D.getDeclSpec(); 2671 2672 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2673 VarDecl::StorageClass StorageClass = VarDecl::None; 2674 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2675 StorageClass = VarDecl::Register; 2676 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2677 Diag(DS.getStorageClassSpecLoc(), 2678 diag::err_invalid_storage_class_in_func_decl); 2679 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2680 } 2681 if (DS.isThreadSpecified()) { 2682 Diag(DS.getThreadSpecLoc(), 2683 diag::err_invalid_storage_class_in_func_decl); 2684 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2685 } 2686 DiagnoseFunctionSpecifiers(D); 2687 2688 // Check that there are no default arguments inside the type of this 2689 // parameter (C++ only). 2690 if (getLangOptions().CPlusPlus) 2691 CheckExtraCXXDefaultArguments(D); 2692 2693 // In this context, we *do not* check D.getInvalidType(). If the declarator 2694 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2695 // though it will not reflect the user specified type. 2696 QualType parmDeclType = GetTypeForDeclarator(D, S); 2697 if (parmDeclType.isNull()) { 2698 D.setInvalidType(true); 2699 parmDeclType = Context.IntTy; 2700 } 2701 2702 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2703 // Can this happen for params? We already checked that they don't conflict 2704 // among each other. Here they can only shadow globals, which is ok. 2705 IdentifierInfo *II = D.getIdentifier(); 2706 if (II) { 2707 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2708 if (PrevDecl->isTemplateParameter()) { 2709 // Maybe we will complain about the shadowed template parameter. 2710 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2711 // Just pretend that we didn't see the previous declaration. 2712 PrevDecl = 0; 2713 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2714 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2715 2716 // Recover by removing the name 2717 II = 0; 2718 D.SetIdentifier(0, D.getIdentifierLoc()); 2719 } 2720 } 2721 } 2722 2723 // Parameters can not be abstract class types. 2724 // For record types, this is done by the AbstractClassUsageDiagnoser once 2725 // the class has been completely parsed. 2726 if (!CurContext->isRecord() && 2727 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2728 diag::err_abstract_type_in_decl, 2729 AbstractParamType)) 2730 D.setInvalidType(true); 2731 2732 QualType T = adjustParameterType(parmDeclType); 2733 2734 ParmVarDecl *New; 2735 if (T == parmDeclType) // parameter type did not need adjustment 2736 New = ParmVarDecl::Create(Context, CurContext, 2737 D.getIdentifierLoc(), II, 2738 parmDeclType, StorageClass, 2739 0); 2740 else // keep track of both the adjusted and unadjusted types 2741 New = OriginalParmVarDecl::Create(Context, CurContext, 2742 D.getIdentifierLoc(), II, T, 2743 parmDeclType, StorageClass, 0); 2744 2745 if (D.getInvalidType()) 2746 New->setInvalidDecl(); 2747 2748 // Parameter declarators cannot be interface types. All ObjC objects are 2749 // passed by reference. 2750 if (T->isObjCInterfaceType()) { 2751 Diag(D.getIdentifierLoc(), 2752 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2753 New->setInvalidDecl(); 2754 } 2755 2756 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2757 if (D.getCXXScopeSpec().isSet()) { 2758 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2759 << D.getCXXScopeSpec().getRange(); 2760 New->setInvalidDecl(); 2761 } 2762 2763 // Add the parameter declaration into this scope. 2764 S->AddDecl(DeclPtrTy::make(New)); 2765 if (II) 2766 IdResolver.AddDecl(New); 2767 2768 ProcessDeclAttributes(New, D); 2769 return DeclPtrTy::make(New); 2770} 2771 2772void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2773 SourceLocation LocAfterDecls) { 2774 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2775 "Not a function declarator!"); 2776 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2777 2778 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2779 // for a K&R function. 2780 if (!FTI.hasPrototype) { 2781 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2782 --i; 2783 if (FTI.ArgInfo[i].Param == 0) { 2784 std::string Code = " int "; 2785 Code += FTI.ArgInfo[i].Ident->getName(); 2786 Code += ";\n"; 2787 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2788 << FTI.ArgInfo[i].Ident 2789 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2790 2791 // Implicitly declare the argument as type 'int' for lack of a better 2792 // type. 2793 DeclSpec DS; 2794 const char* PrevSpec; // unused 2795 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2796 PrevSpec); 2797 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2798 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2799 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2800 } 2801 } 2802 } 2803} 2804 2805Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2806 Declarator &D) { 2807 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2808 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2809 "Not a function declarator!"); 2810 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2811 2812 if (FTI.hasPrototype) { 2813 // FIXME: Diagnose arguments without names in C. 2814 } 2815 2816 Scope *ParentScope = FnBodyScope->getParent(); 2817 2818 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2819 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2820} 2821 2822Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2823 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2824 2825 // See if this is a redefinition. 2826 const FunctionDecl *Definition; 2827 if (FD->getBody(Context, Definition)) { 2828 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2829 Diag(Definition->getLocation(), diag::note_previous_definition); 2830 } 2831 2832 // Builtin functions cannot be defined. 2833 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2834 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2835 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2836 FD->setInvalidDecl(); 2837 } 2838 } 2839 2840 // The return type of a function definition must be complete 2841 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2842 QualType ResultType = FD->getResultType(); 2843 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2844 RequireCompleteType(FD->getLocation(), ResultType, 2845 diag::err_func_def_incomplete_result)) 2846 FD->setInvalidDecl(); 2847 2848 // GNU warning -Wmissing-prototypes: 2849 // Warn if a global function is defined without a previous 2850 // prototype declaration. This warning is issued even if the 2851 // definition itself provides a prototype. The aim is to detect 2852 // global functions that fail to be declared in header files. 2853 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2854 !FD->isMain()) { 2855 bool MissingPrototype = true; 2856 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2857 Prev; Prev = Prev->getPreviousDeclaration()) { 2858 // Ignore any declarations that occur in function or method 2859 // scope, because they aren't visible from the header. 2860 if (Prev->getDeclContext()->isFunctionOrMethod()) 2861 continue; 2862 2863 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2864 break; 2865 } 2866 2867 if (MissingPrototype) 2868 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2869 } 2870 2871 PushDeclContext(FnBodyScope, FD); 2872 2873 // Check the validity of our function parameters 2874 CheckParmsForFunctionDef(FD); 2875 2876 // Introduce our parameters into the function scope 2877 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2878 ParmVarDecl *Param = FD->getParamDecl(p); 2879 Param->setOwningFunction(FD); 2880 2881 // If this has an identifier, add it to the scope stack. 2882 if (Param->getIdentifier()) 2883 PushOnScopeChains(Param, FnBodyScope); 2884 } 2885 2886 // Checking attributes of current function definition 2887 // dllimport attribute. 2888 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2889 // dllimport attribute cannot be applied to definition. 2890 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2891 Diag(FD->getLocation(), 2892 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2893 << "dllimport"; 2894 FD->setInvalidDecl(); 2895 return DeclPtrTy::make(FD); 2896 } else { 2897 // If a symbol previously declared dllimport is later defined, the 2898 // attribute is ignored in subsequent references, and a warning is 2899 // emitted. 2900 Diag(FD->getLocation(), 2901 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2902 << FD->getNameAsCString() << "dllimport"; 2903 } 2904 } 2905 return DeclPtrTy::make(FD); 2906} 2907 2908 2909 2910/// TODO: statement expressions, for (int x[n]; ;), case. 2911/// TODO: check the body of an objc method. 2912 2913// TODO: Consider wording like: "branching bypasses declaration of 2914// variable-length" 2915 2916 2917/// JumpScopeChecker - This object is used by Sema to diagnose invalid jumps 2918/// into VLA and other protected scopes. For example, this rejects: 2919/// goto L; 2920/// int a[n]; 2921/// L: 2922/// 2923namespace { 2924class JumpScopeChecker { 2925 Sema &S; 2926 2927 /// GotoScope - This is a record that we use to keep track of all of the scopes 2928 /// that are introduced by VLAs and other things that scope jumps like gotos. 2929 /// This scope tree has nothing to do with the source scope tree, because you 2930 /// can have multiple VLA scopes per compound statement, and most compound 2931 /// statements don't introduce any scopes. 2932 struct GotoScope { 2933 /// ParentScope - The index in ScopeMap of the parent scope. This is 0 for 2934 /// the parent scope is the function body. 2935 unsigned ParentScope; 2936 2937 /// Diag - The diagnostic to emit if there is a jump into this scope. 2938 unsigned Diag; 2939 2940 /// Loc - Location to emit the diagnostic. 2941 SourceLocation Loc; 2942 2943 GotoScope(unsigned parentScope, unsigned diag, SourceLocation L) 2944 : ParentScope(parentScope), Diag(diag), Loc(L) {} 2945 }; 2946 2947 llvm::SmallVector<GotoScope, 48> Scopes; 2948 llvm::DenseMap<Stmt*, unsigned> LabelAndGotoScopes; 2949 llvm::SmallVector<Stmt*, 16> Jumps; 2950public: 2951 JumpScopeChecker(CompoundStmt *Body, Sema &S); 2952private: 2953 bool StatementCreatesScope(DeclStmt *S, unsigned ParentScope); 2954 void BuildScopeInformation(Stmt *S, unsigned ParentScope); 2955 void VerifyJumps(); 2956 void CheckJump(Stmt *From, Stmt *To, 2957 SourceLocation DiagLoc, unsigned JumpDiag); 2958}; 2959} // end anonymous namespace 2960 2961 2962JumpScopeChecker::JumpScopeChecker(CompoundStmt *Body, Sema &s) : S(s) { 2963 // Add a scope entry for function scope. 2964 Scopes.push_back(GotoScope(~0U, ~0U, SourceLocation())); 2965 2966 // Build information for the top level compound statement, so that we have a 2967 // defined scope record for every "goto" and label. 2968 BuildScopeInformation(Body, 0); 2969 2970 // Check that all jumps we saw are kosher. 2971 VerifyJumps(); 2972} 2973 2974/// StatementCreatesScope - Return true if the specified statement should start 2975/// a new cleanup scope that cannot be entered with a goto. When this returns 2976/// true it pushes a new scope onto the top of Scopes, indicating what scope to 2977/// use for sub-statements. 2978bool JumpScopeChecker::StatementCreatesScope(DeclStmt *DS, 2979 unsigned ParentScope) { 2980 // The decl statement creates a scope if any of the decls in it are VLAs or 2981 // have the cleanup attribute. 2982 for (DeclStmt::decl_iterator I = DS->decl_begin(), E = DS->decl_end(); 2983 I != E; ++I) { 2984 if (VarDecl *D = dyn_cast<VarDecl>(*I)) { 2985 if (D->getType()->isVariablyModifiedType()) { 2986 Scopes.push_back(GotoScope(ParentScope, 2987 diag::note_protected_by_vla, 2988 D->getLocation())); 2989 return true; // FIXME: Handle int X[n], Y[n+1]; 2990 } 2991 if (D->hasAttr<CleanupAttr>()) { 2992 Scopes.push_back(GotoScope(ParentScope, 2993 diag::note_protected_by_cleanup, 2994 D->getLocation())); 2995 return true; 2996 } 2997 } else if (TypedefDecl *D = dyn_cast<TypedefDecl>(*I)) { 2998 if (D->getUnderlyingType()->isVariablyModifiedType()) { 2999 Scopes.push_back(GotoScope(ParentScope, 3000 diag::note_protected_by_vla_typedef, 3001 D->getLocation())); 3002 return true; 3003 } 3004 } 3005 } 3006 return false; 3007} 3008 3009 3010/// BuildScopeInformation - The statements from CI to CE are known to form a 3011/// coherent VLA scope with a specified parent node. Walk through the 3012/// statements, adding any labels or gotos to LabelAndGotoScopes and recursively 3013/// walking the AST as needed. 3014void JumpScopeChecker::BuildScopeInformation(Stmt *S, unsigned ParentScope) { 3015 3016 // If we found a label, remember that it is in ParentScope scope. 3017 if (isa<LabelStmt>(S) || isa<DefaultStmt>(S) || isa<CaseStmt>(S)) { 3018 LabelAndGotoScopes[S] = ParentScope; 3019 } else if (isa<GotoStmt>(S) || isa<SwitchStmt>(S) || 3020 isa<IndirectGotoStmt>(S)) { 3021 // Remember both what scope a goto is in as well as the fact that we have 3022 // it. This makes the second scan not have to walk the AST again. 3023 LabelAndGotoScopes[S] = ParentScope; 3024 Jumps.push_back(S); 3025 } 3026 3027 for (Stmt::child_iterator CI = S->child_begin(), E = S->child_end(); CI != E; 3028 ++CI) { 3029 Stmt *SubStmt = *CI; 3030 if (SubStmt == 0) continue; 3031 3032 // FIXME: diagnose jumps past initialization: required in C++, warning in C. 3033 // { int X = 4; L: } goto L; 3034 3035 // If this is a declstmt with a VLA definition, it defines a scope from here 3036 // to the end of the containing context. 3037 if (isa<DeclStmt>(SubStmt) && 3038 // If StatementCreatesScope returns true, then it pushed a new scope 3039 // onto Scopes. 3040 StatementCreatesScope(cast<DeclStmt>(SubStmt), ParentScope)) { 3041 // FIXME: what about substatements (initializers) of the DeclStmt itself? 3042 // TODO: int x = ({ int x[n]; label: ... }); // decl stmts matter. 3043 3044 // Continue analyzing the remaining statements in this scope with a new 3045 // parent scope ID. 3046 ParentScope = Scopes.size()-1; 3047 continue; 3048 } 3049 3050 // Disallow jumps into any part of an @try statement by pushing a scope and 3051 // walking all sub-stmts in that scope. 3052 if (ObjCAtTryStmt *AT = dyn_cast<ObjCAtTryStmt>(SubStmt)) { 3053 // Recursively walk the AST for the @try part. 3054 Scopes.push_back(GotoScope(ParentScope,diag::note_protected_by_objc_try, 3055 AT->getAtTryLoc())); 3056 if (Stmt *TryPart = AT->getTryBody()) 3057 BuildScopeInformation(TryPart, Scopes.size()-1); 3058 3059 // Jump from the catch to the finally or try is not valid. 3060 for (ObjCAtCatchStmt *AC = AT->getCatchStmts(); AC; 3061 AC = AC->getNextCatchStmt()) { 3062 Scopes.push_back(GotoScope(ParentScope, 3063 diag::note_protected_by_objc_catch, 3064 AC->getAtCatchLoc())); 3065 // @catches are nested and it isn't 3066 BuildScopeInformation(AC->getCatchBody(), Scopes.size()-1); 3067 } 3068 3069 // Jump from the finally to the try or catch is not valid. 3070 if (ObjCAtFinallyStmt *AF = AT->getFinallyStmt()) { 3071 Scopes.push_back(GotoScope(ParentScope, 3072 diag::note_protected_by_objc_finally, 3073 AF->getAtFinallyLoc())); 3074 BuildScopeInformation(AF, Scopes.size()-1); 3075 } 3076 3077 continue; 3078 } 3079 // FIXME: what about jumps into C++ catch blocks, what are the rules? 3080 3081 // Recursively walk the AST. 3082 BuildScopeInformation(SubStmt, ParentScope); 3083 } 3084} 3085 3086void JumpScopeChecker::VerifyJumps() { 3087 while (!Jumps.empty()) { 3088 Stmt *Jump = Jumps.pop_back_val(); 3089 3090 if (GotoStmt *GS = dyn_cast<GotoStmt>(Jump)) { 3091 CheckJump(GS, GS->getLabel(), GS->getGotoLoc(), 3092 diag::err_goto_into_protected_scope); 3093 } else if (SwitchStmt *SS = dyn_cast<SwitchStmt>(Jump)) { 3094 for (SwitchCase *SC = SS->getSwitchCaseList(); SC; 3095 SC = SC->getNextSwitchCase()) { 3096 assert(LabelAndGotoScopes.count(SC) && "Case not visited?"); 3097 CheckJump(SS, SC, SC->getLocStart(), 3098 diag::err_switch_into_protected_scope); 3099 } 3100 continue; 3101 } else { 3102 assert(isa<IndirectGotoStmt>(Jump)); 3103 // FIXME: Emit an error on indirect gotos when not in scope 0. 3104 continue; 3105 } 3106 } 3107} 3108 3109/// CheckJump - Validate that the specified jump statement is valid: that it is 3110/// jumping within or out of its current scope, not into a deeper one. 3111void JumpScopeChecker::CheckJump(Stmt *From, Stmt *To, 3112 SourceLocation DiagLoc, unsigned JumpDiag) { 3113 assert(LabelAndGotoScopes.count(From) && "Jump didn't get added to scopes?"); 3114 unsigned FromScope = LabelAndGotoScopes[From]; 3115 3116 assert(LabelAndGotoScopes.count(To) && "Jump didn't get added to scopes?"); 3117 unsigned ToScope = LabelAndGotoScopes[To]; 3118 3119 // Common case: exactly the same scope, which is fine. 3120 if (FromScope == ToScope) return; 3121 3122 // The only valid mismatch jump case happens when the jump is more deeply 3123 // nested inside the jump target. Do a quick scan to see if the jump is valid 3124 // because valid code is more common than invalid code. 3125 unsigned TestScope = Scopes[FromScope].ParentScope; 3126 while (TestScope != ~0U) { 3127 // If we found the jump target, then we're jumping out of our current scope, 3128 // which is perfectly fine. 3129 if (TestScope == ToScope) return; 3130 3131 // Otherwise, scan up the hierarchy. 3132 TestScope = Scopes[TestScope].ParentScope; 3133 } 3134 3135 // If we get here, then we know we have invalid code. Diagnose the bad jump, 3136 // and then emit a note at each VLA being jumped out of. 3137 S.Diag(DiagLoc, JumpDiag); 3138 3139 // FIXME: This is N^2 and silly. 3140 while (1) { 3141 // Diagnose that the jump jumps over this declaration. 3142 const GotoScope &TargetScope = Scopes[ToScope]; 3143 S.Diag(TargetScope.Loc, TargetScope.Diag); 3144 3145 // Walk out one level. 3146 ToScope = Scopes[ToScope].ParentScope; 3147 assert(ToScope != ~0U && "Didn't find top-level function scope?"); 3148 3149 // Check to see if the jump is valid now. 3150 unsigned TestScope = FromScope; 3151 while (TestScope != ~0U) { 3152 // If we found the jump target, the the jump became valid. 3153 if (TestScope == ToScope) return; 3154 3155 // Otherwise, scan up the hierarchy. 3156 TestScope = Scopes[TestScope].ParentScope; 3157 } 3158 } 3159} 3160 3161 3162Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3163 Decl *dcl = D.getAs<Decl>(); 3164 CompoundStmt *Body =cast<CompoundStmt>(static_cast<Stmt*>(BodyArg.release())); 3165 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3166 FD->setBody(Body); 3167 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3168 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3169 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3170 MD->setBody(Body); 3171 } else { 3172 Body->Destroy(Context); 3173 return DeclPtrTy(); 3174 } 3175 PopDeclContext(); 3176 // Verify and clean out per-function state. 3177 3178 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3179 3180 // Check goto/label use. 3181 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3182 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3183 LabelStmt *L = I->second; 3184 3185 // Verify that we have no forward references left. If so, there was a goto 3186 // or address of a label taken, but no definition of it. Label fwd 3187 // definitions are indicated with a null substmt. 3188 if (L->getSubStmt() != 0) 3189 continue; 3190 3191 // Emit error. 3192 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3193 3194 // At this point, we have gotos that use the bogus label. Stitch it into 3195 // the function body so that they aren't leaked and that the AST is well 3196 // formed. 3197 if (Body == 0) { 3198 // The whole function wasn't parsed correctly, just delete this. 3199 L->Destroy(Context); 3200 continue; 3201 } 3202 3203 // Otherwise, the body is valid: we want to stitch the label decl into the 3204 // function somewhere so that it is properly owned and so that the goto 3205 // has a valid target. Do this by creating a new compound stmt with the 3206 // label in it. 3207 3208 // Give the label a sub-statement. 3209 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3210 3211 std::vector<Stmt*> Elements(Body->body_begin(), Body->body_end()); 3212 Elements.push_back(L); 3213 Body->setStmts(Context, &Elements[0], Elements.size()); 3214 } 3215 FunctionLabelMap.clear(); 3216 3217 if (!Body) return D; 3218 3219 // Verify that that gotos and switch cases don't jump into scopes illegally. 3220 JumpScopeChecker(Body, *this); 3221 3222 return D; 3223} 3224 3225/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3226/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3227NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3228 IdentifierInfo &II, Scope *S) { 3229 // Before we produce a declaration for an implicitly defined 3230 // function, see whether there was a locally-scoped declaration of 3231 // this name as a function or variable. If so, use that 3232 // (non-visible) declaration, and complain about it. 3233 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3234 = LocallyScopedExternalDecls.find(&II); 3235 if (Pos != LocallyScopedExternalDecls.end()) { 3236 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3237 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3238 return Pos->second; 3239 } 3240 3241 // Extension in C99. Legal in C90, but warn about it. 3242 if (getLangOptions().C99) 3243 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3244 else 3245 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3246 3247 // FIXME: handle stuff like: 3248 // void foo() { extern float X(); } 3249 // void bar() { X(); } <-- implicit decl for X in another scope. 3250 3251 // Set a Declarator for the implicit definition: int foo(); 3252 const char *Dummy; 3253 DeclSpec DS; 3254 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3255 Error = Error; // Silence warning. 3256 assert(!Error && "Error setting up implicit decl!"); 3257 Declarator D(DS, Declarator::BlockContext); 3258 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3259 0, 0, 0, Loc, D), 3260 SourceLocation()); 3261 D.SetIdentifier(&II, Loc); 3262 3263 // Insert this function into translation-unit scope. 3264 3265 DeclContext *PrevDC = CurContext; 3266 CurContext = Context.getTranslationUnitDecl(); 3267 3268 FunctionDecl *FD = 3269 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3270 FD->setImplicit(); 3271 3272 CurContext = PrevDC; 3273 3274 AddKnownFunctionAttributes(FD); 3275 3276 return FD; 3277} 3278 3279/// \brief Adds any function attributes that we know a priori based on 3280/// the declaration of this function. 3281/// 3282/// These attributes can apply both to implicitly-declared builtins 3283/// (like __builtin___printf_chk) or to library-declared functions 3284/// like NSLog or printf. 3285void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3286 if (FD->isInvalidDecl()) 3287 return; 3288 3289 // If this is a built-in function, map its builtin attributes to 3290 // actual attributes. 3291 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3292 // Handle printf-formatting attributes. 3293 unsigned FormatIdx; 3294 bool HasVAListArg; 3295 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3296 if (!FD->getAttr<FormatAttr>()) 3297 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3298 FormatIdx + 2)); 3299 } 3300 3301 // Mark const if we don't care about errno and that is the only 3302 // thing preventing the function from being const. This allows 3303 // IRgen to use LLVM intrinsics for such functions. 3304 if (!getLangOptions().MathErrno && 3305 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3306 if (!FD->getAttr<ConstAttr>()) 3307 FD->addAttr(::new (Context) ConstAttr()); 3308 } 3309 } 3310 3311 IdentifierInfo *Name = FD->getIdentifier(); 3312 if (!Name) 3313 return; 3314 if ((!getLangOptions().CPlusPlus && 3315 FD->getDeclContext()->isTranslationUnit()) || 3316 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3317 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3318 LinkageSpecDecl::lang_c)) { 3319 // Okay: this could be a libc/libm/Objective-C function we know 3320 // about. 3321 } else 3322 return; 3323 3324 unsigned KnownID; 3325 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3326 if (KnownFunctionIDs[KnownID] == Name) 3327 break; 3328 3329 switch (KnownID) { 3330 case id_NSLog: 3331 case id_NSLogv: 3332 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3333 // FIXME: We known better than our headers. 3334 const_cast<FormatAttr *>(Format)->setType("printf"); 3335 } else 3336 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3337 break; 3338 3339 case id_asprintf: 3340 case id_vasprintf: 3341 if (!FD->getAttr<FormatAttr>()) 3342 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3343 break; 3344 3345 default: 3346 // Unknown function or known function without any attributes to 3347 // add. Do nothing. 3348 break; 3349 } 3350} 3351 3352TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3353 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3354 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3355 3356 // Scope manipulation handled by caller. 3357 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3358 D.getIdentifierLoc(), 3359 D.getIdentifier(), 3360 T); 3361 3362 if (TagType *TT = dyn_cast<TagType>(T)) { 3363 TagDecl *TD = TT->getDecl(); 3364 3365 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3366 // keep track of the TypedefDecl. 3367 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3368 TD->setTypedefForAnonDecl(NewTD); 3369 } 3370 3371 if (D.getInvalidType()) 3372 NewTD->setInvalidDecl(); 3373 return NewTD; 3374} 3375 3376/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3377/// former case, Name will be non-null. In the later case, Name will be null. 3378/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3379/// reference/declaration/definition of a tag. 3380Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3381 SourceLocation KWLoc, const CXXScopeSpec &SS, 3382 IdentifierInfo *Name, SourceLocation NameLoc, 3383 AttributeList *Attr, AccessSpecifier AS) { 3384 // If this is not a definition, it must have a name. 3385 assert((Name != 0 || TK == TK_Definition) && 3386 "Nameless record must be a definition!"); 3387 3388 TagDecl::TagKind Kind; 3389 switch (TagSpec) { 3390 default: assert(0 && "Unknown tag type!"); 3391 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3392 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3393 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3394 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3395 } 3396 3397 DeclContext *SearchDC = CurContext; 3398 DeclContext *DC = CurContext; 3399 NamedDecl *PrevDecl = 0; 3400 3401 bool Invalid = false; 3402 3403 if (Name && SS.isNotEmpty()) { 3404 // We have a nested-name tag ('struct foo::bar'). 3405 3406 // Check for invalid 'foo::'. 3407 if (SS.isInvalid()) { 3408 Name = 0; 3409 goto CreateNewDecl; 3410 } 3411 3412 // FIXME: RequireCompleteDeclContext(SS)? 3413 DC = computeDeclContext(SS); 3414 SearchDC = DC; 3415 // Look-up name inside 'foo::'. 3416 PrevDecl = dyn_cast_or_null<TagDecl>( 3417 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3418 3419 // A tag 'foo::bar' must already exist. 3420 if (PrevDecl == 0) { 3421 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3422 Name = 0; 3423 goto CreateNewDecl; 3424 } 3425 } else if (Name) { 3426 // If this is a named struct, check to see if there was a previous forward 3427 // declaration or definition. 3428 // FIXME: We're looking into outer scopes here, even when we 3429 // shouldn't be. Doing so can result in ambiguities that we 3430 // shouldn't be diagnosing. 3431 LookupResult R = LookupName(S, Name, LookupTagName, 3432 /*RedeclarationOnly=*/(TK != TK_Reference)); 3433 if (R.isAmbiguous()) { 3434 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3435 // FIXME: This is not best way to recover from case like: 3436 // 3437 // struct S s; 3438 // 3439 // causes needless "incomplete type" error later. 3440 Name = 0; 3441 PrevDecl = 0; 3442 Invalid = true; 3443 } 3444 else 3445 PrevDecl = R; 3446 3447 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3448 // FIXME: This makes sure that we ignore the contexts associated 3449 // with C structs, unions, and enums when looking for a matching 3450 // tag declaration or definition. See the similar lookup tweak 3451 // in Sema::LookupName; is there a better way to deal with this? 3452 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3453 SearchDC = SearchDC->getParent(); 3454 } 3455 } 3456 3457 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3458 // Maybe we will complain about the shadowed template parameter. 3459 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3460 // Just pretend that we didn't see the previous declaration. 3461 PrevDecl = 0; 3462 } 3463 3464 if (PrevDecl) { 3465 // Check whether the previous declaration is usable. 3466 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3467 3468 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3469 // If this is a use of a previous tag, or if the tag is already declared 3470 // in the same scope (so that the definition/declaration completes or 3471 // rementions the tag), reuse the decl. 3472 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3473 // Make sure that this wasn't declared as an enum and now used as a 3474 // struct or something similar. 3475 if (PrevTagDecl->getTagKind() != Kind) { 3476 bool SafeToContinue 3477 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3478 Kind != TagDecl::TK_enum); 3479 if (SafeToContinue) 3480 Diag(KWLoc, diag::err_use_with_wrong_tag) 3481 << Name 3482 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3483 PrevTagDecl->getKindName()); 3484 else 3485 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3486 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3487 3488 if (SafeToContinue) 3489 Kind = PrevTagDecl->getTagKind(); 3490 else { 3491 // Recover by making this an anonymous redefinition. 3492 Name = 0; 3493 PrevDecl = 0; 3494 Invalid = true; 3495 } 3496 } 3497 3498 if (!Invalid) { 3499 // If this is a use, just return the declaration we found. 3500 3501 // FIXME: In the future, return a variant or some other clue 3502 // for the consumer of this Decl to know it doesn't own it. 3503 // For our current ASTs this shouldn't be a problem, but will 3504 // need to be changed with DeclGroups. 3505 if (TK == TK_Reference) 3506 return DeclPtrTy::make(PrevDecl); 3507 3508 // Diagnose attempts to redefine a tag. 3509 if (TK == TK_Definition) { 3510 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3511 Diag(NameLoc, diag::err_redefinition) << Name; 3512 Diag(Def->getLocation(), diag::note_previous_definition); 3513 // If this is a redefinition, recover by making this 3514 // struct be anonymous, which will make any later 3515 // references get the previous definition. 3516 Name = 0; 3517 PrevDecl = 0; 3518 Invalid = true; 3519 } else { 3520 // If the type is currently being defined, complain 3521 // about a nested redefinition. 3522 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3523 if (Tag->isBeingDefined()) { 3524 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3525 Diag(PrevTagDecl->getLocation(), 3526 diag::note_previous_definition); 3527 Name = 0; 3528 PrevDecl = 0; 3529 Invalid = true; 3530 } 3531 } 3532 3533 // Okay, this is definition of a previously declared or referenced 3534 // tag PrevDecl. We're going to create a new Decl for it. 3535 } 3536 } 3537 // If we get here we have (another) forward declaration or we 3538 // have a definition. Just create a new decl. 3539 } else { 3540 // If we get here, this is a definition of a new tag type in a nested 3541 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3542 // new decl/type. We set PrevDecl to NULL so that the entities 3543 // have distinct types. 3544 PrevDecl = 0; 3545 } 3546 // If we get here, we're going to create a new Decl. If PrevDecl 3547 // is non-NULL, it's a definition of the tag declared by 3548 // PrevDecl. If it's NULL, we have a new definition. 3549 } else { 3550 // PrevDecl is a namespace, template, or anything else 3551 // that lives in the IDNS_Tag identifier namespace. 3552 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3553 // The tag name clashes with a namespace name, issue an error and 3554 // recover by making this tag be anonymous. 3555 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3556 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3557 Name = 0; 3558 PrevDecl = 0; 3559 Invalid = true; 3560 } else { 3561 // The existing declaration isn't relevant to us; we're in a 3562 // new scope, so clear out the previous declaration. 3563 PrevDecl = 0; 3564 } 3565 } 3566 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3567 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3568 // C.scope.pdecl]p5: 3569 // -- for an elaborated-type-specifier of the form 3570 // 3571 // class-key identifier 3572 // 3573 // if the elaborated-type-specifier is used in the 3574 // decl-specifier-seq or parameter-declaration-clause of a 3575 // function defined in namespace scope, the identifier is 3576 // declared as a class-name in the namespace that contains 3577 // the declaration; otherwise, except as a friend 3578 // declaration, the identifier is declared in the smallest 3579 // non-class, non-function-prototype scope that contains the 3580 // declaration. 3581 // 3582 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3583 // C structs and unions. 3584 // 3585 // GNU C also supports this behavior as part of its incomplete 3586 // enum types extension, while GNU C++ does not. 3587 // 3588 // Find the context where we'll be declaring the tag. 3589 // FIXME: We would like to maintain the current DeclContext as the 3590 // lexical context, 3591 while (SearchDC->isRecord()) 3592 SearchDC = SearchDC->getParent(); 3593 3594 // Find the scope where we'll be declaring the tag. 3595 while (S->isClassScope() || 3596 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3597 ((S->getFlags() & Scope::DeclScope) == 0) || 3598 (S->getEntity() && 3599 ((DeclContext *)S->getEntity())->isTransparentContext())) 3600 S = S->getParent(); 3601 } 3602 3603CreateNewDecl: 3604 3605 // If there is an identifier, use the location of the identifier as the 3606 // location of the decl, otherwise use the location of the struct/union 3607 // keyword. 3608 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3609 3610 // Otherwise, create a new declaration. If there is a previous 3611 // declaration of the same entity, the two will be linked via 3612 // PrevDecl. 3613 TagDecl *New; 3614 3615 if (Kind == TagDecl::TK_enum) { 3616 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3617 // enum X { A, B, C } D; D should chain to X. 3618 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3619 cast_or_null<EnumDecl>(PrevDecl)); 3620 // If this is an undefined enum, warn. 3621 if (TK != TK_Definition && !Invalid) { 3622 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3623 : diag::ext_forward_ref_enum; 3624 Diag(Loc, DK); 3625 } 3626 } else { 3627 // struct/union/class 3628 3629 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3630 // struct X { int A; } D; D should chain to X. 3631 if (getLangOptions().CPlusPlus) 3632 // FIXME: Look for a way to use RecordDecl for simple structs. 3633 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3634 cast_or_null<CXXRecordDecl>(PrevDecl)); 3635 else 3636 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3637 cast_or_null<RecordDecl>(PrevDecl)); 3638 } 3639 3640 if (Kind != TagDecl::TK_enum) { 3641 // Handle #pragma pack: if the #pragma pack stack has non-default 3642 // alignment, make up a packed attribute for this decl. These 3643 // attributes are checked when the ASTContext lays out the 3644 // structure. 3645 // 3646 // It is important for implementing the correct semantics that this 3647 // happen here (in act on tag decl). The #pragma pack stack is 3648 // maintained as a result of parser callbacks which can occur at 3649 // many points during the parsing of a struct declaration (because 3650 // the #pragma tokens are effectively skipped over during the 3651 // parsing of the struct). 3652 if (unsigned Alignment = getPragmaPackAlignment()) 3653 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3654 } 3655 3656 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3657 // C++ [dcl.typedef]p3: 3658 // [...] Similarly, in a given scope, a class or enumeration 3659 // shall not be declared with the same name as a typedef-name 3660 // that is declared in that scope and refers to a type other 3661 // than the class or enumeration itself. 3662 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3663 TypedefDecl *PrevTypedef = 0; 3664 if (Lookup.getKind() == LookupResult::Found) 3665 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3666 3667 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3668 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3669 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3670 Diag(Loc, diag::err_tag_definition_of_typedef) 3671 << Context.getTypeDeclType(New) 3672 << PrevTypedef->getUnderlyingType(); 3673 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3674 Invalid = true; 3675 } 3676 } 3677 3678 if (Invalid) 3679 New->setInvalidDecl(); 3680 3681 if (Attr) 3682 ProcessDeclAttributeList(New, Attr); 3683 3684 // If we're declaring or defining a tag in function prototype scope 3685 // in C, note that this type can only be used within the function. 3686 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3687 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3688 3689 // Set the lexical context. If the tag has a C++ scope specifier, the 3690 // lexical context will be different from the semantic context. 3691 New->setLexicalDeclContext(CurContext); 3692 3693 // Set the access specifier. 3694 SetMemberAccessSpecifier(New, PrevDecl, AS); 3695 3696 if (TK == TK_Definition) 3697 New->startDefinition(); 3698 3699 // If this has an identifier, add it to the scope stack. 3700 if (Name) { 3701 S = getNonFieldDeclScope(S); 3702 PushOnScopeChains(New, S); 3703 } else { 3704 CurContext->addDecl(Context, New); 3705 } 3706 3707 return DeclPtrTy::make(New); 3708} 3709 3710void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3711 AdjustDeclIfTemplate(TagD); 3712 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3713 3714 // Enter the tag context. 3715 PushDeclContext(S, Tag); 3716 3717 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3718 FieldCollector->StartClass(); 3719 3720 if (Record->getIdentifier()) { 3721 // C++ [class]p2: 3722 // [...] The class-name is also inserted into the scope of the 3723 // class itself; this is known as the injected-class-name. For 3724 // purposes of access checking, the injected-class-name is treated 3725 // as if it were a public member name. 3726 CXXRecordDecl *InjectedClassName 3727 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3728 CurContext, Record->getLocation(), 3729 Record->getIdentifier(), Record); 3730 InjectedClassName->setImplicit(); 3731 InjectedClassName->setAccess(AS_public); 3732 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3733 InjectedClassName->setDescribedClassTemplate(Template); 3734 PushOnScopeChains(InjectedClassName, S); 3735 assert(InjectedClassName->isInjectedClassName() && 3736 "Broken injected-class-name"); 3737 } 3738 } 3739} 3740 3741void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3742 AdjustDeclIfTemplate(TagD); 3743 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3744 3745 if (isa<CXXRecordDecl>(Tag)) 3746 FieldCollector->FinishClass(); 3747 3748 // Exit this scope of this tag's definition. 3749 PopDeclContext(); 3750 3751 // Notify the consumer that we've defined a tag. 3752 Consumer.HandleTagDeclDefinition(Tag); 3753} 3754 3755bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3756 QualType FieldTy, const Expr *BitWidth) { 3757 // C99 6.7.2.1p4 - verify the field type. 3758 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3759 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3760 // Handle incomplete types with specific error. 3761 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3762 return true; 3763 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3764 << FieldName << FieldTy << BitWidth->getSourceRange(); 3765 } 3766 3767 // If the bit-width is type- or value-dependent, don't try to check 3768 // it now. 3769 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3770 return false; 3771 3772 llvm::APSInt Value; 3773 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3774 return true; 3775 3776 // Zero-width bitfield is ok for anonymous field. 3777 if (Value == 0 && FieldName) 3778 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3779 3780 if (Value.isSigned() && Value.isNegative()) 3781 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3782 << FieldName << Value.toString(10); 3783 3784 if (!FieldTy->isDependentType()) { 3785 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3786 // FIXME: We won't need the 0 size once we check that the field type is valid. 3787 if (TypeSize && Value.getZExtValue() > TypeSize) 3788 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3789 << FieldName << (unsigned)TypeSize; 3790 } 3791 3792 return false; 3793} 3794 3795/// ActOnField - Each field of a struct/union/class is passed into this in order 3796/// to create a FieldDecl object for it. 3797Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3798 SourceLocation DeclStart, 3799 Declarator &D, ExprTy *BitfieldWidth) { 3800 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3801 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3802 AS_public); 3803 return DeclPtrTy::make(Res); 3804} 3805 3806/// HandleField - Analyze a field of a C struct or a C++ data member. 3807/// 3808FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3809 SourceLocation DeclStart, 3810 Declarator &D, Expr *BitWidth, 3811 AccessSpecifier AS) { 3812 IdentifierInfo *II = D.getIdentifier(); 3813 SourceLocation Loc = DeclStart; 3814 if (II) Loc = D.getIdentifierLoc(); 3815 3816 QualType T = GetTypeForDeclarator(D, S); 3817 if (getLangOptions().CPlusPlus) 3818 CheckExtraCXXDefaultArguments(D); 3819 3820 DiagnoseFunctionSpecifiers(D); 3821 3822 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3823 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3824 PrevDecl = 0; 3825 3826 FieldDecl *NewFD 3827 = CheckFieldDecl(II, T, Record, Loc, 3828 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3829 BitWidth, AS, PrevDecl, &D); 3830 if (NewFD->isInvalidDecl() && PrevDecl) { 3831 // Don't introduce NewFD into scope; there's already something 3832 // with the same name in the same scope. 3833 } else if (II) { 3834 PushOnScopeChains(NewFD, S); 3835 } else 3836 Record->addDecl(Context, NewFD); 3837 3838 return NewFD; 3839} 3840 3841/// \brief Build a new FieldDecl and check its well-formedness. 3842/// 3843/// This routine builds a new FieldDecl given the fields name, type, 3844/// record, etc. \p PrevDecl should refer to any previous declaration 3845/// with the same name and in the same scope as the field to be 3846/// created. 3847/// 3848/// \returns a new FieldDecl. 3849/// 3850/// \todo The Declarator argument is a hack. It will be removed once 3851FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3852 RecordDecl *Record, SourceLocation Loc, 3853 bool Mutable, Expr *BitWidth, 3854 AccessSpecifier AS, NamedDecl *PrevDecl, 3855 Declarator *D) { 3856 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3857 bool InvalidDecl = false; 3858 3859 // If we receive a broken type, recover by assuming 'int' and 3860 // marking this declaration as invalid. 3861 if (T.isNull()) { 3862 InvalidDecl = true; 3863 T = Context.IntTy; 3864 } 3865 3866 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3867 // than a variably modified type. 3868 if (T->isVariablyModifiedType()) { 3869 bool SizeIsNegative; 3870 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3871 SizeIsNegative); 3872 if (!FixedTy.isNull()) { 3873 Diag(Loc, diag::warn_illegal_constant_array_size); 3874 T = FixedTy; 3875 } else { 3876 if (SizeIsNegative) 3877 Diag(Loc, diag::err_typecheck_negative_array_size); 3878 else 3879 Diag(Loc, diag::err_typecheck_field_variable_size); 3880 T = Context.IntTy; 3881 InvalidDecl = true; 3882 } 3883 } 3884 3885 // Fields can not have abstract class types 3886 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3887 AbstractFieldType)) 3888 InvalidDecl = true; 3889 3890 // If this is declared as a bit-field, check the bit-field. 3891 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3892 InvalidDecl = true; 3893 DeleteExpr(BitWidth); 3894 BitWidth = 0; 3895 } 3896 3897 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3898 Mutable); 3899 3900 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3901 Diag(Loc, diag::err_duplicate_member) << II; 3902 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3903 NewFD->setInvalidDecl(); 3904 Record->setInvalidDecl(); 3905 } 3906 3907 if (getLangOptions().CPlusPlus && !T->isPODType()) 3908 cast<CXXRecordDecl>(Record)->setPOD(false); 3909 3910 // FIXME: We need to pass in the attributes given an AST 3911 // representation, not a parser representation. 3912 if (D) 3913 ProcessDeclAttributes(NewFD, *D); 3914 3915 if (T.isObjCGCWeak()) 3916 Diag(Loc, diag::warn_attribute_weak_on_field); 3917 3918 if (InvalidDecl) 3919 NewFD->setInvalidDecl(); 3920 3921 NewFD->setAccess(AS); 3922 3923 // C++ [dcl.init.aggr]p1: 3924 // An aggregate is an array or a class (clause 9) with [...] no 3925 // private or protected non-static data members (clause 11). 3926 // A POD must be an aggregate. 3927 if (getLangOptions().CPlusPlus && 3928 (AS == AS_private || AS == AS_protected)) { 3929 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3930 CXXRecord->setAggregate(false); 3931 CXXRecord->setPOD(false); 3932 } 3933 3934 return NewFD; 3935} 3936 3937/// TranslateIvarVisibility - Translate visibility from a token ID to an 3938/// AST enum value. 3939static ObjCIvarDecl::AccessControl 3940TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3941 switch (ivarVisibility) { 3942 default: assert(0 && "Unknown visitibility kind"); 3943 case tok::objc_private: return ObjCIvarDecl::Private; 3944 case tok::objc_public: return ObjCIvarDecl::Public; 3945 case tok::objc_protected: return ObjCIvarDecl::Protected; 3946 case tok::objc_package: return ObjCIvarDecl::Package; 3947 } 3948} 3949 3950/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3951/// in order to create an IvarDecl object for it. 3952Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3953 SourceLocation DeclStart, 3954 Declarator &D, ExprTy *BitfieldWidth, 3955 tok::ObjCKeywordKind Visibility) { 3956 3957 IdentifierInfo *II = D.getIdentifier(); 3958 Expr *BitWidth = (Expr*)BitfieldWidth; 3959 SourceLocation Loc = DeclStart; 3960 if (II) Loc = D.getIdentifierLoc(); 3961 3962 // FIXME: Unnamed fields can be handled in various different ways, for 3963 // example, unnamed unions inject all members into the struct namespace! 3964 3965 QualType T = GetTypeForDeclarator(D, S); 3966 bool InvalidDecl = false; 3967 if (T.isNull()) { 3968 InvalidDecl = true; 3969 T = Context.IntTy; 3970 } 3971 3972 if (BitWidth) { 3973 // 6.7.2.1p3, 6.7.2.1p4 3974 if (VerifyBitField(Loc, II, T, BitWidth)) { 3975 InvalidDecl = true; 3976 DeleteExpr(BitWidth); 3977 BitWidth = 0; 3978 } 3979 } else { 3980 // Not a bitfield. 3981 3982 // validate II. 3983 3984 } 3985 3986 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3987 // than a variably modified type. 3988 if (T->isVariablyModifiedType()) { 3989 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3990 InvalidDecl = true; 3991 } 3992 3993 // Get the visibility (access control) for this ivar. 3994 ObjCIvarDecl::AccessControl ac = 3995 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3996 : ObjCIvarDecl::None; 3997 3998 // Construct the decl. 3999 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 4000 (Expr *)BitfieldWidth); 4001 4002 if (II) { 4003 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4004 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 4005 && !isa<TagDecl>(PrevDecl)) { 4006 Diag(Loc, diag::err_duplicate_member) << II; 4007 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4008 NewID->setInvalidDecl(); 4009 } 4010 } 4011 4012 // Process attributes attached to the ivar. 4013 ProcessDeclAttributes(NewID, D); 4014 4015 if (D.getInvalidType() || InvalidDecl) 4016 NewID->setInvalidDecl(); 4017 4018 if (II) { 4019 // FIXME: When interfaces are DeclContexts, we'll need to add 4020 // these to the interface. 4021 S->AddDecl(DeclPtrTy::make(NewID)); 4022 IdResolver.AddDecl(NewID); 4023 } 4024 4025 return DeclPtrTy::make(NewID); 4026} 4027 4028void Sema::ActOnFields(Scope* S, 4029 SourceLocation RecLoc, DeclPtrTy RecDecl, 4030 DeclPtrTy *Fields, unsigned NumFields, 4031 SourceLocation LBrac, SourceLocation RBrac, 4032 AttributeList *Attr) { 4033 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4034 assert(EnclosingDecl && "missing record or interface decl"); 4035 4036 // If the decl this is being inserted into is invalid, then it may be a 4037 // redeclaration or some other bogus case. Don't try to add fields to it. 4038 if (EnclosingDecl->isInvalidDecl()) { 4039 // FIXME: Deallocate fields? 4040 return; 4041 } 4042 4043 4044 // Verify that all the fields are okay. 4045 unsigned NumNamedMembers = 0; 4046 llvm::SmallVector<FieldDecl*, 32> RecFields; 4047 4048 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4049 for (unsigned i = 0; i != NumFields; ++i) { 4050 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4051 4052 // Get the type for the field. 4053 Type *FDTy = FD->getType().getTypePtr(); 4054 4055 if (!FD->isAnonymousStructOrUnion()) { 4056 // Remember all fields written by the user. 4057 RecFields.push_back(FD); 4058 } 4059 4060 // If the field is already invalid for some reason, don't emit more 4061 // diagnostics about it. 4062 if (FD->isInvalidDecl()) 4063 continue; 4064 4065 // C99 6.7.2.1p2: 4066 // A structure or union shall not contain a member with 4067 // incomplete or function type (hence, a structure shall not 4068 // contain an instance of itself, but may contain a pointer to 4069 // an instance of itself), except that the last member of a 4070 // structure with more than one named member may have incomplete 4071 // array type; such a structure (and any union containing, 4072 // possibly recursively, a member that is such a structure) 4073 // shall not be a member of a structure or an element of an 4074 // array. 4075 if (FDTy->isFunctionType()) { 4076 // Field declared as a function. 4077 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4078 << FD->getDeclName(); 4079 FD->setInvalidDecl(); 4080 EnclosingDecl->setInvalidDecl(); 4081 continue; 4082 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4083 Record && Record->isStruct()) { 4084 // Flexible array member. 4085 if (NumNamedMembers < 1) { 4086 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4087 << FD->getDeclName(); 4088 FD->setInvalidDecl(); 4089 EnclosingDecl->setInvalidDecl(); 4090 continue; 4091 } 4092 // Okay, we have a legal flexible array member at the end of the struct. 4093 if (Record) 4094 Record->setHasFlexibleArrayMember(true); 4095 } else if (!FDTy->isDependentType() && 4096 RequireCompleteType(FD->getLocation(), FD->getType(), 4097 diag::err_field_incomplete)) { 4098 // Incomplete type 4099 FD->setInvalidDecl(); 4100 EnclosingDecl->setInvalidDecl(); 4101 continue; 4102 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 4103 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4104 // If this is a member of a union, then entire union becomes "flexible". 4105 if (Record && Record->isUnion()) { 4106 Record->setHasFlexibleArrayMember(true); 4107 } else { 4108 // If this is a struct/class and this is not the last element, reject 4109 // it. Note that GCC supports variable sized arrays in the middle of 4110 // structures. 4111 if (i != NumFields-1) 4112 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4113 << FD->getDeclName(); 4114 else { 4115 // We support flexible arrays at the end of structs in 4116 // other structs as an extension. 4117 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4118 << FD->getDeclName(); 4119 if (Record) 4120 Record->setHasFlexibleArrayMember(true); 4121 } 4122 } 4123 } 4124 } else if (FDTy->isObjCInterfaceType()) { 4125 /// A field cannot be an Objective-c object 4126 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4127 FD->setInvalidDecl(); 4128 EnclosingDecl->setInvalidDecl(); 4129 continue; 4130 } 4131 // Keep track of the number of named members. 4132 if (FD->getIdentifier()) 4133 ++NumNamedMembers; 4134 } 4135 4136 // Okay, we successfully defined 'Record'. 4137 if (Record) { 4138 Record->completeDefinition(Context); 4139 } else { 4140 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 4141 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4142 ID->setIVarList(ClsFields, RecFields.size(), Context); 4143 ID->setLocEnd(RBrac); 4144 4145 // Must enforce the rule that ivars in the base classes may not be 4146 // duplicates. 4147 if (ID->getSuperClass()) { 4148 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4149 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4150 ObjCIvarDecl* Ivar = (*IVI); 4151 IdentifierInfo *II = Ivar->getIdentifier(); 4152 ObjCIvarDecl* prevIvar = 4153 ID->getSuperClass()->lookupInstanceVariable(Context, II); 4154 if (prevIvar) { 4155 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4156 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4157 } 4158 } 4159 } 4160 } else if (ObjCImplementationDecl *IMPDecl = 4161 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4162 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4163 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 4164 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4165 } 4166 } 4167 4168 if (Attr) 4169 ProcessDeclAttributeList(Record, Attr); 4170} 4171 4172EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4173 EnumConstantDecl *LastEnumConst, 4174 SourceLocation IdLoc, 4175 IdentifierInfo *Id, 4176 ExprArg val) { 4177 Expr *Val = (Expr *)val.get(); 4178 4179 llvm::APSInt EnumVal(32); 4180 QualType EltTy; 4181 if (Val && !Val->isTypeDependent()) { 4182 // Make sure to promote the operand type to int. 4183 UsualUnaryConversions(Val); 4184 if (Val != val.get()) { 4185 val.release(); 4186 val = Val; 4187 } 4188 4189 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4190 SourceLocation ExpLoc; 4191 if (!Val->isValueDependent() && 4192 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4193 Val = 0; 4194 } else { 4195 EltTy = Val->getType(); 4196 } 4197 } 4198 4199 if (!Val) { 4200 if (LastEnumConst) { 4201 // Assign the last value + 1. 4202 EnumVal = LastEnumConst->getInitVal(); 4203 ++EnumVal; 4204 4205 // Check for overflow on increment. 4206 if (EnumVal < LastEnumConst->getInitVal()) 4207 Diag(IdLoc, diag::warn_enum_value_overflow); 4208 4209 EltTy = LastEnumConst->getType(); 4210 } else { 4211 // First value, set to zero. 4212 EltTy = Context.IntTy; 4213 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4214 } 4215 } 4216 4217 val.release(); 4218 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4219 Val, EnumVal); 4220} 4221 4222 4223Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4224 DeclPtrTy lastEnumConst, 4225 SourceLocation IdLoc, 4226 IdentifierInfo *Id, 4227 SourceLocation EqualLoc, ExprTy *val) { 4228 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4229 EnumConstantDecl *LastEnumConst = 4230 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4231 Expr *Val = static_cast<Expr*>(val); 4232 4233 // The scope passed in may not be a decl scope. Zip up the scope tree until 4234 // we find one that is. 4235 S = getNonFieldDeclScope(S); 4236 4237 // Verify that there isn't already something declared with this name in this 4238 // scope. 4239 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4240 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4241 // Maybe we will complain about the shadowed template parameter. 4242 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4243 // Just pretend that we didn't see the previous declaration. 4244 PrevDecl = 0; 4245 } 4246 4247 if (PrevDecl) { 4248 // When in C++, we may get a TagDecl with the same name; in this case the 4249 // enum constant will 'hide' the tag. 4250 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4251 "Received TagDecl when not in C++!"); 4252 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4253 if (isa<EnumConstantDecl>(PrevDecl)) 4254 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4255 else 4256 Diag(IdLoc, diag::err_redefinition) << Id; 4257 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4258 if (Val) Val->Destroy(Context); 4259 return DeclPtrTy(); 4260 } 4261 } 4262 4263 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4264 IdLoc, Id, Owned(Val)); 4265 4266 // Register this decl in the current scope stack. 4267 if (New) 4268 PushOnScopeChains(New, S); 4269 4270 return DeclPtrTy::make(New); 4271} 4272 4273// FIXME: For consistency with ActOnFields(), we should have the parser 4274// pass in the source location for the left/right braces. 4275void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4276 DeclPtrTy *Elements, unsigned NumElements) { 4277 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4278 QualType EnumType = Context.getTypeDeclType(Enum); 4279 4280 // TODO: If the result value doesn't fit in an int, it must be a long or long 4281 // long value. ISO C does not support this, but GCC does as an extension, 4282 // emit a warning. 4283 unsigned IntWidth = Context.Target.getIntWidth(); 4284 4285 // Verify that all the values are okay, compute the size of the values, and 4286 // reverse the list. 4287 unsigned NumNegativeBits = 0; 4288 unsigned NumPositiveBits = 0; 4289 4290 // Keep track of whether all elements have type int. 4291 bool AllElementsInt = true; 4292 4293 for (unsigned i = 0; i != NumElements; ++i) { 4294 EnumConstantDecl *ECD = 4295 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4296 if (!ECD) continue; // Already issued a diagnostic. 4297 4298 // If the enum value doesn't fit in an int, emit an extension warning. 4299 const llvm::APSInt &InitVal = ECD->getInitVal(); 4300 assert(InitVal.getBitWidth() >= IntWidth && 4301 "Should have promoted value to int"); 4302 if (InitVal.getBitWidth() > IntWidth) { 4303 llvm::APSInt V(InitVal); 4304 V.trunc(IntWidth); 4305 V.extend(InitVal.getBitWidth()); 4306 if (V != InitVal) 4307 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4308 << InitVal.toString(10); 4309 } 4310 4311 // Keep track of the size of positive and negative values. 4312 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4313 NumPositiveBits = std::max(NumPositiveBits, 4314 (unsigned)InitVal.getActiveBits()); 4315 else 4316 NumNegativeBits = std::max(NumNegativeBits, 4317 (unsigned)InitVal.getMinSignedBits()); 4318 4319 // Keep track of whether every enum element has type int (very commmon). 4320 if (AllElementsInt) 4321 AllElementsInt = ECD->getType() == Context.IntTy; 4322 } 4323 4324 // Figure out the type that should be used for this enum. 4325 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4326 QualType BestType; 4327 unsigned BestWidth; 4328 4329 if (NumNegativeBits) { 4330 // If there is a negative value, figure out the smallest integer type (of 4331 // int/long/longlong) that fits. 4332 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4333 BestType = Context.IntTy; 4334 BestWidth = IntWidth; 4335 } else { 4336 BestWidth = Context.Target.getLongWidth(); 4337 4338 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4339 BestType = Context.LongTy; 4340 else { 4341 BestWidth = Context.Target.getLongLongWidth(); 4342 4343 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4344 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4345 BestType = Context.LongLongTy; 4346 } 4347 } 4348 } else { 4349 // If there is no negative value, figure out which of uint, ulong, ulonglong 4350 // fits. 4351 if (NumPositiveBits <= IntWidth) { 4352 BestType = Context.UnsignedIntTy; 4353 BestWidth = IntWidth; 4354 } else if (NumPositiveBits <= 4355 (BestWidth = Context.Target.getLongWidth())) { 4356 BestType = Context.UnsignedLongTy; 4357 } else { 4358 BestWidth = Context.Target.getLongLongWidth(); 4359 assert(NumPositiveBits <= BestWidth && 4360 "How could an initializer get larger than ULL?"); 4361 BestType = Context.UnsignedLongLongTy; 4362 } 4363 } 4364 4365 // Loop over all of the enumerator constants, changing their types to match 4366 // the type of the enum if needed. 4367 for (unsigned i = 0; i != NumElements; ++i) { 4368 EnumConstantDecl *ECD = 4369 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4370 if (!ECD) continue; // Already issued a diagnostic. 4371 4372 // Standard C says the enumerators have int type, but we allow, as an 4373 // extension, the enumerators to be larger than int size. If each 4374 // enumerator value fits in an int, type it as an int, otherwise type it the 4375 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4376 // that X has type 'int', not 'unsigned'. 4377 if (ECD->getType() == Context.IntTy) { 4378 // Make sure the init value is signed. 4379 llvm::APSInt IV = ECD->getInitVal(); 4380 IV.setIsSigned(true); 4381 ECD->setInitVal(IV); 4382 4383 if (getLangOptions().CPlusPlus) 4384 // C++ [dcl.enum]p4: Following the closing brace of an 4385 // enum-specifier, each enumerator has the type of its 4386 // enumeration. 4387 ECD->setType(EnumType); 4388 continue; // Already int type. 4389 } 4390 4391 // Determine whether the value fits into an int. 4392 llvm::APSInt InitVal = ECD->getInitVal(); 4393 bool FitsInInt; 4394 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4395 FitsInInt = InitVal.getActiveBits() < IntWidth; 4396 else 4397 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4398 4399 // If it fits into an integer type, force it. Otherwise force it to match 4400 // the enum decl type. 4401 QualType NewTy; 4402 unsigned NewWidth; 4403 bool NewSign; 4404 if (FitsInInt) { 4405 NewTy = Context.IntTy; 4406 NewWidth = IntWidth; 4407 NewSign = true; 4408 } else if (ECD->getType() == BestType) { 4409 // Already the right type! 4410 if (getLangOptions().CPlusPlus) 4411 // C++ [dcl.enum]p4: Following the closing brace of an 4412 // enum-specifier, each enumerator has the type of its 4413 // enumeration. 4414 ECD->setType(EnumType); 4415 continue; 4416 } else { 4417 NewTy = BestType; 4418 NewWidth = BestWidth; 4419 NewSign = BestType->isSignedIntegerType(); 4420 } 4421 4422 // Adjust the APSInt value. 4423 InitVal.extOrTrunc(NewWidth); 4424 InitVal.setIsSigned(NewSign); 4425 ECD->setInitVal(InitVal); 4426 4427 // Adjust the Expr initializer and type. 4428 if (ECD->getInitExpr()) 4429 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4430 /*isLvalue=*/false)); 4431 if (getLangOptions().CPlusPlus) 4432 // C++ [dcl.enum]p4: Following the closing brace of an 4433 // enum-specifier, each enumerator has the type of its 4434 // enumeration. 4435 ECD->setType(EnumType); 4436 else 4437 ECD->setType(NewTy); 4438 } 4439 4440 Enum->completeDefinition(Context, BestType); 4441} 4442 4443Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4444 ExprArg expr) { 4445 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4446 4447 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4448 Loc, AsmString)); 4449} 4450 4451