SemaDecl.cpp revision 38c5ebd7b1b65304c7b5c7b9bf3f9162df22e77d
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 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1568 // then it shall have block scope. 1569 QualType T = NewTD->getUnderlyingType(); 1570 if (T->isVariablyModifiedType()) { 1571 CurFunctionNeedsScopeChecking = true; 1572 1573 if (S->getFnParent() == 0) { 1574 bool SizeIsNegative; 1575 QualType FixedTy = 1576 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1577 if (!FixedTy.isNull()) { 1578 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1579 NewTD->setUnderlyingType(FixedTy); 1580 } else { 1581 if (SizeIsNegative) 1582 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1583 else if (T->isVariableArrayType()) 1584 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1585 else 1586 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1587 InvalidDecl = true; 1588 } 1589 } 1590 } 1591 return NewTD; 1592} 1593 1594/// \brief Determines whether the given declaration is an out-of-scope 1595/// previous declaration. 1596/// 1597/// This routine should be invoked when name lookup has found a 1598/// previous declaration (PrevDecl) that is not in the scope where a 1599/// new declaration by the same name is being introduced. If the new 1600/// declaration occurs in a local scope, previous declarations with 1601/// linkage may still be considered previous declarations (C99 1602/// 6.2.2p4-5, C++ [basic.link]p6). 1603/// 1604/// \param PrevDecl the previous declaration found by name 1605/// lookup 1606/// 1607/// \param DC the context in which the new declaration is being 1608/// declared. 1609/// 1610/// \returns true if PrevDecl is an out-of-scope previous declaration 1611/// for a new delcaration with the same name. 1612static bool 1613isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1614 ASTContext &Context) { 1615 if (!PrevDecl) 1616 return 0; 1617 1618 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1619 // case we need to check each of the overloaded functions. 1620 if (!PrevDecl->hasLinkage()) 1621 return false; 1622 1623 if (Context.getLangOptions().CPlusPlus) { 1624 // C++ [basic.link]p6: 1625 // If there is a visible declaration of an entity with linkage 1626 // having the same name and type, ignoring entities declared 1627 // outside the innermost enclosing namespace scope, the block 1628 // scope declaration declares that same entity and receives the 1629 // linkage of the previous declaration. 1630 DeclContext *OuterContext = DC->getLookupContext(); 1631 if (!OuterContext->isFunctionOrMethod()) 1632 // This rule only applies to block-scope declarations. 1633 return false; 1634 else { 1635 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1636 if (PrevOuterContext->isRecord()) 1637 // We found a member function: ignore it. 1638 return false; 1639 else { 1640 // Find the innermost enclosing namespace for the new and 1641 // previous declarations. 1642 while (!OuterContext->isFileContext()) 1643 OuterContext = OuterContext->getParent(); 1644 while (!PrevOuterContext->isFileContext()) 1645 PrevOuterContext = PrevOuterContext->getParent(); 1646 1647 // The previous declaration is in a different namespace, so it 1648 // isn't the same function. 1649 if (OuterContext->getPrimaryContext() != 1650 PrevOuterContext->getPrimaryContext()) 1651 return false; 1652 } 1653 } 1654 } 1655 1656 return true; 1657} 1658 1659NamedDecl* 1660Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1661 QualType R,NamedDecl* PrevDecl, bool& InvalidDecl, 1662 bool &Redeclaration) { 1663 DeclarationName Name = GetNameForDeclarator(D); 1664 1665 // Check that there are no default arguments (C++ only). 1666 if (getLangOptions().CPlusPlus) 1667 CheckExtraCXXDefaultArguments(D); 1668 1669 VarDecl *NewVD; 1670 VarDecl::StorageClass SC; 1671 switch (D.getDeclSpec().getStorageClassSpec()) { 1672 default: assert(0 && "Unknown storage class!"); 1673 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1674 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1675 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1676 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1677 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1678 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1679 case DeclSpec::SCS_mutable: 1680 // mutable can only appear on non-static class members, so it's always 1681 // an error here 1682 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1683 InvalidDecl = true; 1684 SC = VarDecl::None; 1685 break; 1686 } 1687 1688 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1689 if (!II) { 1690 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1691 << Name.getAsString(); 1692 return 0; 1693 } 1694 1695 DiagnoseFunctionSpecifiers(D); 1696 1697 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1698 if (!DC->isRecord() && S->getFnParent() == 0) { 1699 // C99 6.9p2: The storage-class specifiers auto and register shall not 1700 // appear in the declaration specifiers in an external declaration. 1701 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1702 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1703 InvalidDecl = true; 1704 } 1705 } 1706 if (DC->isRecord() && !CurContext->isRecord()) { 1707 // This is an out-of-line definition of a static data member. 1708 if (SC == VarDecl::Static) { 1709 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1710 diag::err_static_out_of_line) 1711 << CodeModificationHint::CreateRemoval( 1712 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1713 } else if (SC == VarDecl::None) 1714 SC = VarDecl::Static; 1715 } 1716 1717 // The variable can not 1718 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1719 II, R, SC, 1720 // FIXME: Move to DeclGroup... 1721 D.getDeclSpec().getSourceRange().getBegin()); 1722 NewVD->setThreadSpecified(ThreadSpecified); 1723 1724 // Set the lexical context. If the declarator has a C++ scope specifier, the 1725 // lexical context will be different from the semantic context. 1726 NewVD->setLexicalDeclContext(CurContext); 1727 1728 // Handle attributes prior to checking for duplicates in MergeVarDecl 1729 ProcessDeclAttributes(NewVD, D); 1730 1731 // Handle GNU asm-label extension (encoded as an attribute). 1732 if (Expr *E = (Expr*) D.getAsmLabel()) { 1733 // The parser guarantees this is a string. 1734 StringLiteral *SE = cast<StringLiteral>(E); 1735 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1736 SE->getByteLength()))); 1737 } 1738 1739 // If name lookup finds a previous declaration that is not in the 1740 // same scope as the new declaration, this may still be an 1741 // acceptable redeclaration. 1742 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1743 !(NewVD->hasLinkage() && 1744 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1745 PrevDecl = 0; 1746 1747 // Merge the decl with the existing one if appropriate. 1748 if (PrevDecl) { 1749 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1750 // The user tried to define a non-static data member 1751 // out-of-line (C++ [dcl.meaning]p1). 1752 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1753 << D.getCXXScopeSpec().getRange(); 1754 PrevDecl = 0; 1755 InvalidDecl = true; 1756 } 1757 } else if (D.getCXXScopeSpec().isSet()) { 1758 // No previous declaration in the qualifying scope. 1759 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1760 << Name << D.getCXXScopeSpec().getRange(); 1761 InvalidDecl = true; 1762 } 1763 1764 if (CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration)) 1765 InvalidDecl = true; 1766 1767 // If this is a locally-scoped extern C variable, update the map of 1768 // such variables. 1769 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1770 !InvalidDecl) 1771 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1772 1773 return NewVD; 1774} 1775 1776/// \brief Perform semantic checking on a newly-created variable 1777/// declaration. 1778/// 1779/// This routine performs all of the type-checking required for a 1780/// variable declaration once it has been build. It is used both to 1781/// check variables after they have been parsed and their declarators 1782/// have been translated into a declaration, and to check 1783/// 1784/// \returns true if an error was encountered, false otherwise. 1785bool Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1786 bool &Redeclaration) { 1787 bool Invalid = false; 1788 1789 QualType T = NewVD->getType(); 1790 1791 if (T->isObjCInterfaceType()) { 1792 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1793 Invalid = true; 1794 } 1795 1796 // The variable can not have an abstract class type. 1797 if (RequireNonAbstractType(NewVD->getLocation(), T, 1798 diag::err_abstract_type_in_decl, 1799 AbstractVariableType)) 1800 Invalid = true; 1801 1802 // Emit an error if an address space was applied to decl with local storage. 1803 // This includes arrays of objects with address space qualifiers, but not 1804 // automatic variables that point to other address spaces. 1805 // ISO/IEC TR 18037 S5.1.2 1806 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1807 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1808 Invalid = true; 1809 } 1810 1811 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1812 && !NewVD->hasAttr<BlocksAttr>()) 1813 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1814 1815 bool isVM = T->isVariablyModifiedType(); 1816 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1817 CurFunctionNeedsScopeChecking = true; 1818 1819 if ((isVM && NewVD->hasLinkage()) || 1820 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1821 bool SizeIsNegative; 1822 QualType FixedTy = 1823 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1824 if (!FixedTy.isNull()) { 1825 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1826 NewVD->setType(FixedTy); 1827 } else if (T->isVariableArrayType()) { 1828 Invalid = true; 1829 1830 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1831 // FIXME: This won't give the correct result for 1832 // int a[10][n]; 1833 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1834 1835 if (NewVD->isFileVarDecl()) 1836 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1837 << SizeRange; 1838 else if (NewVD->getStorageClass() == VarDecl::Static) 1839 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1840 << SizeRange; 1841 else 1842 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1843 << SizeRange; 1844 } else { 1845 Invalid = true; 1846 1847 if (NewVD->isFileVarDecl()) 1848 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1849 else 1850 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1851 } 1852 } 1853 1854 if (!PrevDecl && NewVD->isExternC(Context)) { 1855 // Since we did not find anything by this name and we're declaring 1856 // an extern "C" variable, look for a non-visible extern "C" 1857 // declaration with the same name. 1858 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1859 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1860 if (Pos != LocallyScopedExternalDecls.end()) 1861 PrevDecl = Pos->second; 1862 } 1863 1864 if (!Invalid && T->isVoidType() && !NewVD->hasExternalStorage()) { 1865 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1866 << T; 1867 Invalid = true; 1868 } 1869 1870 if (PrevDecl) { 1871 Redeclaration = true; 1872 if (MergeVarDecl(NewVD, PrevDecl)) 1873 Invalid = true; 1874 } 1875 1876 return NewVD->isInvalidDecl() || Invalid; 1877} 1878 1879NamedDecl* 1880Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1881 QualType R, NamedDecl* PrevDecl, 1882 bool IsFunctionDefinition, 1883 bool& InvalidDecl, bool &Redeclaration) { 1884 assert(R.getTypePtr()->isFunctionType()); 1885 1886 DeclarationName Name = GetNameForDeclarator(D); 1887 FunctionDecl::StorageClass SC = FunctionDecl::None; 1888 switch (D.getDeclSpec().getStorageClassSpec()) { 1889 default: assert(0 && "Unknown storage class!"); 1890 case DeclSpec::SCS_auto: 1891 case DeclSpec::SCS_register: 1892 case DeclSpec::SCS_mutable: 1893 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1894 diag::err_typecheck_sclass_func); 1895 InvalidDecl = true; 1896 break; 1897 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1898 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1899 case DeclSpec::SCS_static: { 1900 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1901 // C99 6.7.1p5: 1902 // The declaration of an identifier for a function that has 1903 // block scope shall have no explicit storage-class specifier 1904 // other than extern 1905 // See also (C++ [dcl.stc]p4). 1906 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1907 diag::err_static_block_func); 1908 SC = FunctionDecl::None; 1909 } else 1910 SC = FunctionDecl::Static; 1911 break; 1912 } 1913 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1914 } 1915 1916 bool isInline = D.getDeclSpec().isInlineSpecified(); 1917 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1918 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1919 1920 // Check that the return type is not an abstract class type. 1921 // For record types, this is done by the AbstractClassUsageDiagnoser once 1922 // the class has been completely parsed. 1923 if (!DC->isRecord() && 1924 RequireNonAbstractType(D.getIdentifierLoc(), 1925 R->getAsFunctionType()->getResultType(), 1926 diag::err_abstract_type_in_decl, 1927 AbstractReturnType)) 1928 InvalidDecl = true; 1929 1930 // Do not allow returning a objc interface by-value. 1931 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1932 Diag(D.getIdentifierLoc(), 1933 diag::err_object_cannot_be_passed_returned_by_value) << 0 1934 << R->getAsFunctionType()->getResultType(); 1935 InvalidDecl = true; 1936 } 1937 1938 bool isVirtualOkay = false; 1939 FunctionDecl *NewFD; 1940 if (D.getKind() == Declarator::DK_Constructor) { 1941 // This is a C++ constructor declaration. 1942 assert(DC->isRecord() && 1943 "Constructors can only be declared in a member context"); 1944 1945 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1946 1947 // Create the new declaration 1948 NewFD = CXXConstructorDecl::Create(Context, 1949 cast<CXXRecordDecl>(DC), 1950 D.getIdentifierLoc(), Name, R, 1951 isExplicit, isInline, 1952 /*isImplicitlyDeclared=*/false); 1953 1954 if (InvalidDecl) 1955 NewFD->setInvalidDecl(); 1956 } else if (D.getKind() == Declarator::DK_Destructor) { 1957 // This is a C++ destructor declaration. 1958 if (DC->isRecord()) { 1959 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1960 1961 NewFD = CXXDestructorDecl::Create(Context, 1962 cast<CXXRecordDecl>(DC), 1963 D.getIdentifierLoc(), Name, R, 1964 isInline, 1965 /*isImplicitlyDeclared=*/false); 1966 1967 if (InvalidDecl) 1968 NewFD->setInvalidDecl(); 1969 1970 isVirtualOkay = true; 1971 } else { 1972 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1973 1974 // Create a FunctionDecl to satisfy the function definition parsing 1975 // code path. 1976 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1977 Name, R, SC, isInline, 1978 /*hasPrototype=*/true, 1979 // FIXME: Move to DeclGroup... 1980 D.getDeclSpec().getSourceRange().getBegin()); 1981 InvalidDecl = true; 1982 NewFD->setInvalidDecl(); 1983 } 1984 } else if (D.getKind() == Declarator::DK_Conversion) { 1985 if (!DC->isRecord()) { 1986 Diag(D.getIdentifierLoc(), 1987 diag::err_conv_function_not_member); 1988 return 0; 1989 } else { 1990 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1991 1992 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1993 D.getIdentifierLoc(), Name, R, 1994 isInline, isExplicit); 1995 1996 if (InvalidDecl) 1997 NewFD->setInvalidDecl(); 1998 1999 isVirtualOkay = true; 2000 } 2001 } else if (DC->isRecord()) { 2002 // This is a C++ method declaration. 2003 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2004 D.getIdentifierLoc(), Name, R, 2005 (SC == FunctionDecl::Static), isInline); 2006 2007 isVirtualOkay = (SC != FunctionDecl::Static); 2008 } else { 2009 // Determine whether the function was written with a 2010 // prototype. This true when: 2011 // - we're in C++ (where every function has a prototype), 2012 // - there is a prototype in the declarator, or 2013 // - the type R of the function is some kind of typedef or other reference 2014 // to a type name (which eventually refers to a function type). 2015 bool HasPrototype = 2016 getLangOptions().CPlusPlus || 2017 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2018 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2019 2020 NewFD = FunctionDecl::Create(Context, DC, 2021 D.getIdentifierLoc(), 2022 Name, R, SC, isInline, HasPrototype, 2023 // FIXME: Move to DeclGroup... 2024 D.getDeclSpec().getSourceRange().getBegin()); 2025 } 2026 2027 // Set the lexical context. If the declarator has a C++ 2028 // scope specifier, the lexical context will be different 2029 // from the semantic context. 2030 NewFD->setLexicalDeclContext(CurContext); 2031 2032 // C++ [dcl.fct.spec]p5: 2033 // The virtual specifier shall only be used in declarations of 2034 // nonstatic class member functions that appear within a 2035 // member-specification of a class declaration; see 10.3. 2036 // 2037 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2038 // function is also virtual if it overrides an already virtual 2039 // function. This is important to do here because it's part of the 2040 // declaration. 2041 if (isVirtual && !InvalidDecl) { 2042 if (!isVirtualOkay) { 2043 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2044 diag::err_virtual_non_function); 2045 } else if (!CurContext->isRecord()) { 2046 // 'virtual' was specified outside of the class. 2047 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2048 << CodeModificationHint::CreateRemoval( 2049 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2050 } else { 2051 // Okay: Add virtual to the method. 2052 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2053 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2054 CurClass->setAggregate(false); 2055 CurClass->setPOD(false); 2056 CurClass->setPolymorphic(true); 2057 CurClass->setHasTrivialConstructor(false); 2058 } 2059 } 2060 2061 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2062 !CurContext->isRecord()) { 2063 // C++ [class.static]p1: 2064 // A data or function member of a class may be declared static 2065 // in a class definition, in which case it is a static member of 2066 // the class. 2067 2068 // Complain about the 'static' specifier if it's on an out-of-line 2069 // member function definition. 2070 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2071 diag::err_static_out_of_line) 2072 << CodeModificationHint::CreateRemoval( 2073 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2074 } 2075 2076 // Handle GNU asm-label extension (encoded as an attribute). 2077 if (Expr *E = (Expr*) D.getAsmLabel()) { 2078 // The parser guarantees this is a string. 2079 StringLiteral *SE = cast<StringLiteral>(E); 2080 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2081 SE->getByteLength()))); 2082 } 2083 2084 // Copy the parameter declarations from the declarator D to 2085 // the function declaration NewFD, if they are available. 2086 if (D.getNumTypeObjects() > 0) { 2087 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2088 2089 // Create Decl objects for each parameter, adding them to the 2090 // FunctionDecl. 2091 llvm::SmallVector<ParmVarDecl*, 16> Params; 2092 2093 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2094 // function that takes no arguments, not a function that takes a 2095 // single void argument. 2096 // We let through "const void" here because Sema::GetTypeForDeclarator 2097 // already checks for that case. 2098 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2099 FTI.ArgInfo[0].Param && 2100 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2101 // empty arg list, don't push any params. 2102 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2103 2104 // In C++, the empty parameter-type-list must be spelled "void"; a 2105 // typedef of void is not permitted. 2106 if (getLangOptions().CPlusPlus && 2107 Param->getType().getUnqualifiedType() != Context.VoidTy) { 2108 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2109 } 2110 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2111 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2112 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2113 } 2114 2115 NewFD->setParams(Context, &Params[0], Params.size()); 2116 } else if (R->getAsTypedefType()) { 2117 // When we're declaring a function with a typedef, as in the 2118 // following example, we'll need to synthesize (unnamed) 2119 // parameters for use in the declaration. 2120 // 2121 // @code 2122 // typedef void fn(int); 2123 // fn f; 2124 // @endcode 2125 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 2126 if (!FT) { 2127 // This is a typedef of a function with no prototype, so we 2128 // don't need to do anything. 2129 } else if ((FT->getNumArgs() == 0) || 2130 (FT->getNumArgs() == 1 && !FT->isVariadic() && 2131 FT->getArgType(0)->isVoidType())) { 2132 // This is a zero-argument function. We don't need to do anything. 2133 } else { 2134 // Synthesize a parameter for each argument type. 2135 llvm::SmallVector<ParmVarDecl*, 16> Params; 2136 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 2137 ArgType != FT->arg_type_end(); ++ArgType) { 2138 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2139 SourceLocation(), 0, 2140 *ArgType, VarDecl::None, 2141 0); 2142 Param->setImplicit(); 2143 Params.push_back(Param); 2144 } 2145 2146 NewFD->setParams(Context, &Params[0], Params.size()); 2147 } 2148 } 2149 2150 // If name lookup finds a previous declaration that is not in the 2151 // same scope as the new declaration, this may still be an 2152 // acceptable redeclaration. 2153 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2154 !(NewFD->hasLinkage() && 2155 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2156 PrevDecl = 0; 2157 2158 // Perform semantic checking on the function declaration. 2159 bool OverloadableAttrRequired = false; // FIXME: HACK! 2160 if (CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2161 /*FIXME:*/OverloadableAttrRequired)) 2162 InvalidDecl = true; 2163 2164 if (D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2165 // An out-of-line member function declaration must also be a 2166 // definition (C++ [dcl.meaning]p1). 2167 if (!IsFunctionDefinition) { 2168 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2169 << D.getCXXScopeSpec().getRange(); 2170 InvalidDecl = true; 2171 } else if (!Redeclaration) { 2172 // The user tried to provide an out-of-line definition for a 2173 // function that is a member of a class or namespace, but there 2174 // was no such member function declared (C++ [class.mfct]p2, 2175 // C++ [namespace.memdef]p2). For example: 2176 // 2177 // class X { 2178 // void f() const; 2179 // }; 2180 // 2181 // void X::f() { } // ill-formed 2182 // 2183 // Complain about this problem, and attempt to suggest close 2184 // matches (e.g., those that differ only in cv-qualifiers and 2185 // whether the parameter types are references). 2186 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2187 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2188 InvalidDecl = true; 2189 2190 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2191 true); 2192 assert(!Prev.isAmbiguous() && 2193 "Cannot have an ambiguity in previous-declaration lookup"); 2194 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2195 Func != FuncEnd; ++Func) { 2196 if (isa<FunctionDecl>(*Func) && 2197 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2198 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2199 } 2200 2201 PrevDecl = 0; 2202 } 2203 } 2204 2205 // Handle attributes. We need to have merged decls when handling attributes 2206 // (for example to check for conflicts, etc). 2207 // FIXME: This needs to happen before we merge declarations. Then, 2208 // let attribute merging cope with attribute conflicts. 2209 ProcessDeclAttributes(NewFD, D); 2210 AddKnownFunctionAttributes(NewFD); 2211 2212 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2213 // If a function name is overloadable in C, then every function 2214 // with that name must be marked "overloadable". 2215 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2216 << Redeclaration << NewFD; 2217 if (PrevDecl) 2218 Diag(PrevDecl->getLocation(), 2219 diag::note_attribute_overloadable_prev_overload); 2220 NewFD->addAttr(::new (Context) OverloadableAttr()); 2221 } 2222 2223 // If this is a locally-scoped extern C function, update the 2224 // map of such names. 2225 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2226 && !InvalidDecl) 2227 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2228 2229 return NewFD; 2230} 2231 2232/// \brief Perform semantic checking of a new function declaration. 2233/// 2234/// Performs semantic analysis of the new function declaration 2235/// NewFD. This routine performs all semantic checking that does not 2236/// require the actual declarator involved in the declaration, and is 2237/// used both for the declaration of functions as they are parsed 2238/// (called via ActOnDeclarator) and for the declaration of functions 2239/// that have been instantiated via C++ template instantiation (called 2240/// via InstantiateDecl). 2241/// 2242/// \returns true if there was an error, false otherwise. 2243bool Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2244 bool &Redeclaration, 2245 bool &OverloadableAttrRequired) { 2246 bool InvalidDecl = false; 2247 2248 // Semantic checking for this function declaration (in isolation). 2249 if (getLangOptions().CPlusPlus) { 2250 // C++-specific checks. 2251 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 2252 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 2253 else if (isa<CXXDestructorDecl>(NewFD)) { 2254 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2255 Record->setUserDeclaredDestructor(true); 2256 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2257 // user-defined destructor. 2258 Record->setPOD(false); 2259 2260 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2261 // declared destructor. 2262 Record->setHasTrivialDestructor(false); 2263 } else if (CXXConversionDecl *Conversion 2264 = dyn_cast<CXXConversionDecl>(NewFD)) 2265 ActOnConversionDeclarator(Conversion); 2266 2267 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2268 if (NewFD->isOverloadedOperator() && 2269 CheckOverloadedOperatorDeclaration(NewFD)) 2270 InvalidDecl = true; 2271 } 2272 2273 // Check for a previous declaration of this name. 2274 if (!PrevDecl && NewFD->isExternC(Context)) { 2275 // Since we did not find anything by this name and we're declaring 2276 // an extern "C" function, look for a non-visible extern "C" 2277 // declaration with the same name. 2278 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2279 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2280 if (Pos != LocallyScopedExternalDecls.end()) 2281 PrevDecl = Pos->second; 2282 } 2283 2284 // Merge or overload the declaration with an existing declaration of 2285 // the same name, if appropriate. 2286 if (PrevDecl) { 2287 // Determine whether NewFD is an overload of PrevDecl or 2288 // a declaration that requires merging. If it's an overload, 2289 // there's no more work to do here; we'll just add the new 2290 // function to the scope. 2291 OverloadedFunctionDecl::function_iterator MatchedDecl; 2292 2293 if (!getLangOptions().CPlusPlus && 2294 AllowOverloadingOfFunction(PrevDecl, Context)) { 2295 OverloadableAttrRequired = true; 2296 2297 // Functions marked "overloadable" must have a prototype (that 2298 // we can't get through declaration merging). 2299 if (!NewFD->getType()->getAsFunctionProtoType()) { 2300 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2301 << NewFD; 2302 InvalidDecl = true; 2303 Redeclaration = true; 2304 2305 // Turn this into a variadic function with no parameters. 2306 QualType R = Context.getFunctionType( 2307 NewFD->getType()->getAsFunctionType()->getResultType(), 2308 0, 0, true, 0); 2309 NewFD->setType(R); 2310 } 2311 } 2312 2313 if (PrevDecl && 2314 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2315 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2316 Redeclaration = true; 2317 Decl *OldDecl = PrevDecl; 2318 2319 // If PrevDecl was an overloaded function, extract the 2320 // FunctionDecl that matched. 2321 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2322 OldDecl = *MatchedDecl; 2323 2324 // NewFD and OldDecl represent declarations that need to be 2325 // merged. 2326 if (MergeFunctionDecl(NewFD, OldDecl)) 2327 InvalidDecl = true; 2328 2329 if (!InvalidDecl) 2330 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2331 } 2332 } 2333 2334 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) { 2335 // In C++, check default arguments now that we have merged decls. Unless 2336 // the lexical context is the class, because in this case this is done 2337 // during delayed parsing anyway. 2338 CheckCXXDefaultArguments(NewFD); 2339 } 2340 2341 return InvalidDecl || NewFD->isInvalidDecl(); 2342} 2343 2344bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2345 // FIXME: Need strict checking. In C89, we need to check for 2346 // any assignment, increment, decrement, function-calls, or 2347 // commas outside of a sizeof. In C99, it's the same list, 2348 // except that the aforementioned are allowed in unevaluated 2349 // expressions. Everything else falls under the 2350 // "may accept other forms of constant expressions" exception. 2351 // (We never end up here for C++, so the constant expression 2352 // rules there don't matter.) 2353 if (Init->isConstantInitializer(Context)) 2354 return false; 2355 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2356 << Init->getSourceRange(); 2357 return true; 2358} 2359 2360void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2361 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2362} 2363 2364/// AddInitializerToDecl - Adds the initializer Init to the 2365/// declaration dcl. If DirectInit is true, this is C++ direct 2366/// initialization rather than copy initialization. 2367void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2368 Decl *RealDecl = dcl.getAs<Decl>(); 2369 // If there is no declaration, there was an error parsing it. Just ignore 2370 // the initializer. 2371 if (RealDecl == 0) 2372 return; 2373 2374 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2375 // With declarators parsed the way they are, the parser cannot 2376 // distinguish between a normal initializer and a pure-specifier. 2377 // Thus this grotesque test. 2378 IntegerLiteral *IL; 2379 Expr *Init = static_cast<Expr *>(init.get()); 2380 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2381 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2382 if (Method->isVirtual()) { 2383 Method->setPure(); 2384 2385 // A class is abstract if at least one function is pure virtual. 2386 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2387 } else if (!Method->isInvalidDecl()) { 2388 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2389 << Method->getDeclName() << Init->getSourceRange(); 2390 Method->setInvalidDecl(); 2391 } 2392 } else { 2393 Diag(Method->getLocation(), diag::err_member_function_initialization) 2394 << Method->getDeclName() << Init->getSourceRange(); 2395 Method->setInvalidDecl(); 2396 } 2397 return; 2398 } 2399 2400 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2401 if (!VDecl) { 2402 if (getLangOptions().CPlusPlus && 2403 RealDecl->getLexicalDeclContext()->isRecord() && 2404 isa<NamedDecl>(RealDecl)) 2405 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2406 << cast<NamedDecl>(RealDecl)->getDeclName(); 2407 else 2408 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2409 RealDecl->setInvalidDecl(); 2410 return; 2411 } 2412 2413 if (!VDecl->getType()->isArrayType() && 2414 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2415 diag::err_typecheck_decl_incomplete_type)) { 2416 RealDecl->setInvalidDecl(); 2417 return; 2418 } 2419 2420 const VarDecl *Def = 0; 2421 if (VDecl->getDefinition(Def)) { 2422 Diag(VDecl->getLocation(), diag::err_redefinition) 2423 << VDecl->getDeclName(); 2424 Diag(Def->getLocation(), diag::note_previous_definition); 2425 VDecl->setInvalidDecl(); 2426 return; 2427 } 2428 2429 // Take ownership of the expression, now that we're sure we have somewhere 2430 // to put it. 2431 Expr *Init = static_cast<Expr *>(init.release()); 2432 assert(Init && "missing initializer"); 2433 2434 // Get the decls type and save a reference for later, since 2435 // CheckInitializerTypes may change it. 2436 QualType DclT = VDecl->getType(), SavT = DclT; 2437 if (VDecl->isBlockVarDecl()) { 2438 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2439 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2440 VDecl->setInvalidDecl(); 2441 } else if (!VDecl->isInvalidDecl()) { 2442 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2443 VDecl->getDeclName(), DirectInit)) 2444 VDecl->setInvalidDecl(); 2445 2446 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2447 // Don't check invalid declarations to avoid emitting useless diagnostics. 2448 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2449 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2450 CheckForConstantInitializer(Init, DclT); 2451 } 2452 } 2453 } else if (VDecl->isStaticDataMember() && 2454 VDecl->getLexicalDeclContext()->isRecord()) { 2455 // This is an in-class initialization for a static data member, e.g., 2456 // 2457 // struct S { 2458 // static const int value = 17; 2459 // }; 2460 2461 // Attach the initializer 2462 VDecl->setInit(Init); 2463 2464 // C++ [class.mem]p4: 2465 // A member-declarator can contain a constant-initializer only 2466 // if it declares a static member (9.4) of const integral or 2467 // const enumeration type, see 9.4.2. 2468 QualType T = VDecl->getType(); 2469 if (!T->isDependentType() && 2470 (!Context.getCanonicalType(T).isConstQualified() || 2471 !T->isIntegralType())) { 2472 Diag(VDecl->getLocation(), diag::err_member_initialization) 2473 << VDecl->getDeclName() << Init->getSourceRange(); 2474 VDecl->setInvalidDecl(); 2475 } else { 2476 // C++ [class.static.data]p4: 2477 // If a static data member is of const integral or const 2478 // enumeration type, its declaration in the class definition 2479 // can specify a constant-initializer which shall be an 2480 // integral constant expression (5.19). 2481 if (!Init->isTypeDependent() && 2482 !Init->getType()->isIntegralType()) { 2483 // We have a non-dependent, non-integral or enumeration type. 2484 Diag(Init->getSourceRange().getBegin(), 2485 diag::err_in_class_initializer_non_integral_type) 2486 << Init->getType() << Init->getSourceRange(); 2487 VDecl->setInvalidDecl(); 2488 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2489 // Check whether the expression is a constant expression. 2490 llvm::APSInt Value; 2491 SourceLocation Loc; 2492 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2493 Diag(Loc, diag::err_in_class_initializer_non_constant) 2494 << Init->getSourceRange(); 2495 VDecl->setInvalidDecl(); 2496 } else if (!VDecl->getType()->isDependentType()) 2497 ImpCastExprToType(Init, VDecl->getType()); 2498 } 2499 } 2500 } else if (VDecl->isFileVarDecl()) { 2501 if (VDecl->getStorageClass() == VarDecl::Extern) 2502 Diag(VDecl->getLocation(), diag::warn_extern_init); 2503 if (!VDecl->isInvalidDecl()) 2504 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2505 VDecl->getDeclName(), DirectInit)) 2506 VDecl->setInvalidDecl(); 2507 2508 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2509 // Don't check invalid declarations to avoid emitting useless diagnostics. 2510 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2511 // C99 6.7.8p4. All file scoped initializers need to be constant. 2512 CheckForConstantInitializer(Init, DclT); 2513 } 2514 } 2515 // If the type changed, it means we had an incomplete type that was 2516 // completed by the initializer. For example: 2517 // int ary[] = { 1, 3, 5 }; 2518 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2519 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2520 VDecl->setType(DclT); 2521 Init->setType(DclT); 2522 } 2523 2524 // Attach the initializer to the decl. 2525 VDecl->setInit(Init); 2526 return; 2527} 2528 2529void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2530 Decl *RealDecl = dcl.getAs<Decl>(); 2531 2532 // If there is no declaration, there was an error parsing it. Just ignore it. 2533 if (RealDecl == 0) 2534 return; 2535 2536 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2537 QualType Type = Var->getType(); 2538 // C++ [dcl.init.ref]p3: 2539 // The initializer can be omitted for a reference only in a 2540 // parameter declaration (8.3.5), in the declaration of a 2541 // function return type, in the declaration of a class member 2542 // within its class declaration (9.2), and where the extern 2543 // specifier is explicitly used. 2544 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2545 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2546 << Var->getDeclName() 2547 << SourceRange(Var->getLocation(), Var->getLocation()); 2548 Var->setInvalidDecl(); 2549 return; 2550 } 2551 2552 // C++ [dcl.init]p9: 2553 // 2554 // If no initializer is specified for an object, and the object 2555 // is of (possibly cv-qualified) non-POD class type (or array 2556 // thereof), the object shall be default-initialized; if the 2557 // object is of const-qualified type, the underlying class type 2558 // shall have a user-declared default constructor. 2559 if (getLangOptions().CPlusPlus) { 2560 QualType InitType = Type; 2561 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2562 InitType = Array->getElementType(); 2563 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2564 CXXRecordDecl *RD = 2565 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2566 CXXConstructorDecl *Constructor = 0; 2567 if (!RequireCompleteType(Var->getLocation(), InitType, 2568 diag::err_invalid_incomplete_type_use)) 2569 Constructor 2570 = PerformInitializationByConstructor(InitType, 0, 0, 2571 Var->getLocation(), 2572 SourceRange(Var->getLocation(), 2573 Var->getLocation()), 2574 Var->getDeclName(), 2575 IK_Default); 2576 if (!Constructor) 2577 Var->setInvalidDecl(); 2578 else if (!RD->hasTrivialConstructor()) 2579 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2580 } 2581 } 2582 2583#if 0 2584 // FIXME: Temporarily disabled because we are not properly parsing 2585 // linkage specifications on declarations, e.g., 2586 // 2587 // extern "C" const CGPoint CGPointerZero; 2588 // 2589 // C++ [dcl.init]p9: 2590 // 2591 // If no initializer is specified for an object, and the 2592 // object is of (possibly cv-qualified) non-POD class type (or 2593 // array thereof), the object shall be default-initialized; if 2594 // the object is of const-qualified type, the underlying class 2595 // type shall have a user-declared default 2596 // constructor. Otherwise, if no initializer is specified for 2597 // an object, the object and its subobjects, if any, have an 2598 // indeterminate initial value; if the object or any of its 2599 // subobjects are of const-qualified type, the program is 2600 // ill-formed. 2601 // 2602 // This isn't technically an error in C, so we don't diagnose it. 2603 // 2604 // FIXME: Actually perform the POD/user-defined default 2605 // constructor check. 2606 if (getLangOptions().CPlusPlus && 2607 Context.getCanonicalType(Type).isConstQualified() && 2608 !Var->hasExternalStorage()) 2609 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2610 << Var->getName() 2611 << SourceRange(Var->getLocation(), Var->getLocation()); 2612#endif 2613 } 2614} 2615 2616Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2617 unsigned NumDecls) { 2618 llvm::SmallVector<Decl*, 8> Decls; 2619 2620 for (unsigned i = 0; i != NumDecls; ++i) 2621 if (Decl *D = Group[i].getAs<Decl>()) 2622 Decls.push_back(D); 2623 2624 // Perform semantic analysis that depends on having fully processed both 2625 // the declarator and initializer. 2626 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2627 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2628 if (!IDecl) 2629 continue; 2630 QualType T = IDecl->getType(); 2631 2632 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2633 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2634 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2635 if (!IDecl->isInvalidDecl() && 2636 RequireCompleteType(IDecl->getLocation(), T, 2637 diag::err_typecheck_decl_incomplete_type)) 2638 IDecl->setInvalidDecl(); 2639 } 2640 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2641 // object that has file scope without an initializer, and without a 2642 // storage-class specifier or with the storage-class specifier "static", 2643 // constitutes a tentative definition. Note: A tentative definition with 2644 // external linkage is valid (C99 6.2.2p5). 2645 if (IDecl->isTentativeDefinition(Context)) { 2646 QualType CheckType = T; 2647 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2648 2649 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2650 if (ArrayT) { 2651 CheckType = ArrayT->getElementType(); 2652 DiagID = diag::err_illegal_decl_array_incomplete_type; 2653 } 2654 2655 if (IDecl->isInvalidDecl()) { 2656 // Do nothing with invalid declarations 2657 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2658 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2659 // C99 6.9.2p3: If the declaration of an identifier for an object is 2660 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2661 // declared type shall not be an incomplete type. 2662 IDecl->setInvalidDecl(); 2663 } 2664 } 2665 } 2666 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2667 &Decls[0], Decls.size())); 2668} 2669 2670 2671/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2672/// to introduce parameters into function prototype scope. 2673Sema::DeclPtrTy 2674Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2675 const DeclSpec &DS = D.getDeclSpec(); 2676 2677 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2678 VarDecl::StorageClass StorageClass = VarDecl::None; 2679 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2680 StorageClass = VarDecl::Register; 2681 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2682 Diag(DS.getStorageClassSpecLoc(), 2683 diag::err_invalid_storage_class_in_func_decl); 2684 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2685 } 2686 if (DS.isThreadSpecified()) { 2687 Diag(DS.getThreadSpecLoc(), 2688 diag::err_invalid_storage_class_in_func_decl); 2689 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2690 } 2691 DiagnoseFunctionSpecifiers(D); 2692 2693 // Check that there are no default arguments inside the type of this 2694 // parameter (C++ only). 2695 if (getLangOptions().CPlusPlus) 2696 CheckExtraCXXDefaultArguments(D); 2697 2698 // In this context, we *do not* check D.getInvalidType(). If the declarator 2699 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2700 // though it will not reflect the user specified type. 2701 QualType parmDeclType = GetTypeForDeclarator(D, S); 2702 if (parmDeclType.isNull()) { 2703 D.setInvalidType(true); 2704 parmDeclType = Context.IntTy; 2705 } 2706 2707 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2708 // Can this happen for params? We already checked that they don't conflict 2709 // among each other. Here they can only shadow globals, which is ok. 2710 IdentifierInfo *II = D.getIdentifier(); 2711 if (II) { 2712 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2713 if (PrevDecl->isTemplateParameter()) { 2714 // Maybe we will complain about the shadowed template parameter. 2715 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2716 // Just pretend that we didn't see the previous declaration. 2717 PrevDecl = 0; 2718 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2719 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2720 2721 // Recover by removing the name 2722 II = 0; 2723 D.SetIdentifier(0, D.getIdentifierLoc()); 2724 } 2725 } 2726 } 2727 2728 // Parameters can not be abstract class types. 2729 // For record types, this is done by the AbstractClassUsageDiagnoser once 2730 // the class has been completely parsed. 2731 if (!CurContext->isRecord() && 2732 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2733 diag::err_abstract_type_in_decl, 2734 AbstractParamType)) 2735 D.setInvalidType(true); 2736 2737 QualType T = adjustParameterType(parmDeclType); 2738 2739 ParmVarDecl *New; 2740 if (T == parmDeclType) // parameter type did not need adjustment 2741 New = ParmVarDecl::Create(Context, CurContext, 2742 D.getIdentifierLoc(), II, 2743 parmDeclType, StorageClass, 2744 0); 2745 else // keep track of both the adjusted and unadjusted types 2746 New = OriginalParmVarDecl::Create(Context, CurContext, 2747 D.getIdentifierLoc(), II, T, 2748 parmDeclType, StorageClass, 0); 2749 2750 if (D.getInvalidType()) 2751 New->setInvalidDecl(); 2752 2753 // Parameter declarators cannot be interface types. All ObjC objects are 2754 // passed by reference. 2755 if (T->isObjCInterfaceType()) { 2756 Diag(D.getIdentifierLoc(), 2757 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2758 New->setInvalidDecl(); 2759 } 2760 2761 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2762 if (D.getCXXScopeSpec().isSet()) { 2763 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2764 << D.getCXXScopeSpec().getRange(); 2765 New->setInvalidDecl(); 2766 } 2767 2768 // Add the parameter declaration into this scope. 2769 S->AddDecl(DeclPtrTy::make(New)); 2770 if (II) 2771 IdResolver.AddDecl(New); 2772 2773 ProcessDeclAttributes(New, D); 2774 return DeclPtrTy::make(New); 2775} 2776 2777void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2778 SourceLocation LocAfterDecls) { 2779 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2780 "Not a function declarator!"); 2781 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2782 2783 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2784 // for a K&R function. 2785 if (!FTI.hasPrototype) { 2786 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2787 --i; 2788 if (FTI.ArgInfo[i].Param == 0) { 2789 std::string Code = " int "; 2790 Code += FTI.ArgInfo[i].Ident->getName(); 2791 Code += ";\n"; 2792 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2793 << FTI.ArgInfo[i].Ident 2794 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2795 2796 // Implicitly declare the argument as type 'int' for lack of a better 2797 // type. 2798 DeclSpec DS; 2799 const char* PrevSpec; // unused 2800 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2801 PrevSpec); 2802 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2803 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2804 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2805 } 2806 } 2807 } 2808} 2809 2810Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2811 Declarator &D) { 2812 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2813 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2814 "Not a function declarator!"); 2815 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2816 2817 if (FTI.hasPrototype) { 2818 // FIXME: Diagnose arguments without names in C. 2819 } 2820 2821 Scope *ParentScope = FnBodyScope->getParent(); 2822 2823 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2824 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2825} 2826 2827Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2828 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2829 2830 CurFunctionNeedsScopeChecking = false; 2831 2832 // See if this is a redefinition. 2833 const FunctionDecl *Definition; 2834 if (FD->getBody(Context, Definition)) { 2835 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2836 Diag(Definition->getLocation(), diag::note_previous_definition); 2837 } 2838 2839 // Builtin functions cannot be defined. 2840 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2841 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2842 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2843 FD->setInvalidDecl(); 2844 } 2845 } 2846 2847 // The return type of a function definition must be complete 2848 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2849 QualType ResultType = FD->getResultType(); 2850 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2851 RequireCompleteType(FD->getLocation(), ResultType, 2852 diag::err_func_def_incomplete_result)) 2853 FD->setInvalidDecl(); 2854 2855 // GNU warning -Wmissing-prototypes: 2856 // Warn if a global function is defined without a previous 2857 // prototype declaration. This warning is issued even if the 2858 // definition itself provides a prototype. The aim is to detect 2859 // global functions that fail to be declared in header files. 2860 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2861 !FD->isMain()) { 2862 bool MissingPrototype = true; 2863 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2864 Prev; Prev = Prev->getPreviousDeclaration()) { 2865 // Ignore any declarations that occur in function or method 2866 // scope, because they aren't visible from the header. 2867 if (Prev->getDeclContext()->isFunctionOrMethod()) 2868 continue; 2869 2870 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2871 break; 2872 } 2873 2874 if (MissingPrototype) 2875 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2876 } 2877 2878 PushDeclContext(FnBodyScope, FD); 2879 2880 // Check the validity of our function parameters 2881 CheckParmsForFunctionDef(FD); 2882 2883 // Introduce our parameters into the function scope 2884 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2885 ParmVarDecl *Param = FD->getParamDecl(p); 2886 Param->setOwningFunction(FD); 2887 2888 // If this has an identifier, add it to the scope stack. 2889 if (Param->getIdentifier()) 2890 PushOnScopeChains(Param, FnBodyScope); 2891 } 2892 2893 // Checking attributes of current function definition 2894 // dllimport attribute. 2895 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2896 // dllimport attribute cannot be applied to definition. 2897 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2898 Diag(FD->getLocation(), 2899 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2900 << "dllimport"; 2901 FD->setInvalidDecl(); 2902 return DeclPtrTy::make(FD); 2903 } else { 2904 // If a symbol previously declared dllimport is later defined, the 2905 // attribute is ignored in subsequent references, and a warning is 2906 // emitted. 2907 Diag(FD->getLocation(), 2908 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2909 << FD->getNameAsCString() << "dllimport"; 2910 } 2911 } 2912 return DeclPtrTy::make(FD); 2913} 2914 2915 2916Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 2917 Decl *dcl = D.getAs<Decl>(); 2918 CompoundStmt *Body =cast<CompoundStmt>(static_cast<Stmt*>(BodyArg.release())); 2919 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2920 FD->setBody(Body); 2921 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2922 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2923 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2924 MD->setBody(Body); 2925 } else { 2926 Body->Destroy(Context); 2927 return DeclPtrTy(); 2928 } 2929 PopDeclContext(); 2930 // Verify and clean out per-function state. 2931 2932 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 2933 2934 // Check goto/label use. 2935 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2936 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 2937 LabelStmt *L = I->second; 2938 2939 // Verify that we have no forward references left. If so, there was a goto 2940 // or address of a label taken, but no definition of it. Label fwd 2941 // definitions are indicated with a null substmt. 2942 if (L->getSubStmt() != 0) 2943 continue; 2944 2945 // Emit error. 2946 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2947 2948 // At this point, we have gotos that use the bogus label. Stitch it into 2949 // the function body so that they aren't leaked and that the AST is well 2950 // formed. 2951 if (Body == 0) { 2952 // The whole function wasn't parsed correctly, just delete this. 2953 L->Destroy(Context); 2954 continue; 2955 } 2956 2957 // Otherwise, the body is valid: we want to stitch the label decl into the 2958 // function somewhere so that it is properly owned and so that the goto 2959 // has a valid target. Do this by creating a new compound stmt with the 2960 // label in it. 2961 2962 // Give the label a sub-statement. 2963 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2964 2965 std::vector<Stmt*> Elements(Body->body_begin(), Body->body_end()); 2966 Elements.push_back(L); 2967 Body->setStmts(Context, &Elements[0], Elements.size()); 2968 } 2969 FunctionLabelMap.clear(); 2970 2971 if (!Body) return D; 2972 2973 // Verify that that gotos and switch cases don't jump into scopes illegally. 2974 if (CurFunctionNeedsScopeChecking) 2975 DiagnoseInvalidJumps(Body); 2976 2977 return D; 2978} 2979 2980/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2981/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2982NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2983 IdentifierInfo &II, Scope *S) { 2984 // Before we produce a declaration for an implicitly defined 2985 // function, see whether there was a locally-scoped declaration of 2986 // this name as a function or variable. If so, use that 2987 // (non-visible) declaration, and complain about it. 2988 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2989 = LocallyScopedExternalDecls.find(&II); 2990 if (Pos != LocallyScopedExternalDecls.end()) { 2991 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 2992 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 2993 return Pos->second; 2994 } 2995 2996 // Extension in C99. Legal in C90, but warn about it. 2997 if (getLangOptions().C99) 2998 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2999 else 3000 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3001 3002 // FIXME: handle stuff like: 3003 // void foo() { extern float X(); } 3004 // void bar() { X(); } <-- implicit decl for X in another scope. 3005 3006 // Set a Declarator for the implicit definition: int foo(); 3007 const char *Dummy; 3008 DeclSpec DS; 3009 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3010 Error = Error; // Silence warning. 3011 assert(!Error && "Error setting up implicit decl!"); 3012 Declarator D(DS, Declarator::BlockContext); 3013 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3014 0, 0, 0, Loc, D), 3015 SourceLocation()); 3016 D.SetIdentifier(&II, Loc); 3017 3018 // Insert this function into translation-unit scope. 3019 3020 DeclContext *PrevDC = CurContext; 3021 CurContext = Context.getTranslationUnitDecl(); 3022 3023 FunctionDecl *FD = 3024 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3025 FD->setImplicit(); 3026 3027 CurContext = PrevDC; 3028 3029 AddKnownFunctionAttributes(FD); 3030 3031 return FD; 3032} 3033 3034/// \brief Adds any function attributes that we know a priori based on 3035/// the declaration of this function. 3036/// 3037/// These attributes can apply both to implicitly-declared builtins 3038/// (like __builtin___printf_chk) or to library-declared functions 3039/// like NSLog or printf. 3040void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3041 if (FD->isInvalidDecl()) 3042 return; 3043 3044 // If this is a built-in function, map its builtin attributes to 3045 // actual attributes. 3046 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3047 // Handle printf-formatting attributes. 3048 unsigned FormatIdx; 3049 bool HasVAListArg; 3050 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3051 if (!FD->getAttr<FormatAttr>()) 3052 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3053 FormatIdx + 2)); 3054 } 3055 3056 // Mark const if we don't care about errno and that is the only 3057 // thing preventing the function from being const. This allows 3058 // IRgen to use LLVM intrinsics for such functions. 3059 if (!getLangOptions().MathErrno && 3060 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3061 if (!FD->getAttr<ConstAttr>()) 3062 FD->addAttr(::new (Context) ConstAttr()); 3063 } 3064 } 3065 3066 IdentifierInfo *Name = FD->getIdentifier(); 3067 if (!Name) 3068 return; 3069 if ((!getLangOptions().CPlusPlus && 3070 FD->getDeclContext()->isTranslationUnit()) || 3071 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3072 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3073 LinkageSpecDecl::lang_c)) { 3074 // Okay: this could be a libc/libm/Objective-C function we know 3075 // about. 3076 } else 3077 return; 3078 3079 unsigned KnownID; 3080 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3081 if (KnownFunctionIDs[KnownID] == Name) 3082 break; 3083 3084 switch (KnownID) { 3085 case id_NSLog: 3086 case id_NSLogv: 3087 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3088 // FIXME: We known better than our headers. 3089 const_cast<FormatAttr *>(Format)->setType("printf"); 3090 } else 3091 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3092 break; 3093 3094 case id_asprintf: 3095 case id_vasprintf: 3096 if (!FD->getAttr<FormatAttr>()) 3097 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3098 break; 3099 3100 default: 3101 // Unknown function or known function without any attributes to 3102 // add. Do nothing. 3103 break; 3104 } 3105} 3106 3107TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3108 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3109 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3110 3111 // Scope manipulation handled by caller. 3112 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3113 D.getIdentifierLoc(), 3114 D.getIdentifier(), 3115 T); 3116 3117 if (TagType *TT = dyn_cast<TagType>(T)) { 3118 TagDecl *TD = TT->getDecl(); 3119 3120 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3121 // keep track of the TypedefDecl. 3122 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3123 TD->setTypedefForAnonDecl(NewTD); 3124 } 3125 3126 if (D.getInvalidType()) 3127 NewTD->setInvalidDecl(); 3128 return NewTD; 3129} 3130 3131/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3132/// former case, Name will be non-null. In the later case, Name will be null. 3133/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3134/// reference/declaration/definition of a tag. 3135Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3136 SourceLocation KWLoc, const CXXScopeSpec &SS, 3137 IdentifierInfo *Name, SourceLocation NameLoc, 3138 AttributeList *Attr, AccessSpecifier AS) { 3139 // If this is not a definition, it must have a name. 3140 assert((Name != 0 || TK == TK_Definition) && 3141 "Nameless record must be a definition!"); 3142 3143 TagDecl::TagKind Kind; 3144 switch (TagSpec) { 3145 default: assert(0 && "Unknown tag type!"); 3146 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3147 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3148 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3149 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3150 } 3151 3152 DeclContext *SearchDC = CurContext; 3153 DeclContext *DC = CurContext; 3154 NamedDecl *PrevDecl = 0; 3155 3156 bool Invalid = false; 3157 3158 if (Name && SS.isNotEmpty()) { 3159 // We have a nested-name tag ('struct foo::bar'). 3160 3161 // Check for invalid 'foo::'. 3162 if (SS.isInvalid()) { 3163 Name = 0; 3164 goto CreateNewDecl; 3165 } 3166 3167 // FIXME: RequireCompleteDeclContext(SS)? 3168 DC = computeDeclContext(SS); 3169 SearchDC = DC; 3170 // Look-up name inside 'foo::'. 3171 PrevDecl = dyn_cast_or_null<TagDecl>( 3172 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3173 3174 // A tag 'foo::bar' must already exist. 3175 if (PrevDecl == 0) { 3176 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3177 Name = 0; 3178 goto CreateNewDecl; 3179 } 3180 } else if (Name) { 3181 // If this is a named struct, check to see if there was a previous forward 3182 // declaration or definition. 3183 // FIXME: We're looking into outer scopes here, even when we 3184 // shouldn't be. Doing so can result in ambiguities that we 3185 // shouldn't be diagnosing. 3186 LookupResult R = LookupName(S, Name, LookupTagName, 3187 /*RedeclarationOnly=*/(TK != TK_Reference)); 3188 if (R.isAmbiguous()) { 3189 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3190 // FIXME: This is not best way to recover from case like: 3191 // 3192 // struct S s; 3193 // 3194 // causes needless "incomplete type" error later. 3195 Name = 0; 3196 PrevDecl = 0; 3197 Invalid = true; 3198 } 3199 else 3200 PrevDecl = R; 3201 3202 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3203 // FIXME: This makes sure that we ignore the contexts associated 3204 // with C structs, unions, and enums when looking for a matching 3205 // tag declaration or definition. See the similar lookup tweak 3206 // in Sema::LookupName; is there a better way to deal with this? 3207 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3208 SearchDC = SearchDC->getParent(); 3209 } 3210 } 3211 3212 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3213 // Maybe we will complain about the shadowed template parameter. 3214 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3215 // Just pretend that we didn't see the previous declaration. 3216 PrevDecl = 0; 3217 } 3218 3219 if (PrevDecl) { 3220 // Check whether the previous declaration is usable. 3221 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3222 3223 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3224 // If this is a use of a previous tag, or if the tag is already declared 3225 // in the same scope (so that the definition/declaration completes or 3226 // rementions the tag), reuse the decl. 3227 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3228 // Make sure that this wasn't declared as an enum and now used as a 3229 // struct or something similar. 3230 if (PrevTagDecl->getTagKind() != Kind) { 3231 bool SafeToContinue 3232 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3233 Kind != TagDecl::TK_enum); 3234 if (SafeToContinue) 3235 Diag(KWLoc, diag::err_use_with_wrong_tag) 3236 << Name 3237 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3238 PrevTagDecl->getKindName()); 3239 else 3240 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3241 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3242 3243 if (SafeToContinue) 3244 Kind = PrevTagDecl->getTagKind(); 3245 else { 3246 // Recover by making this an anonymous redefinition. 3247 Name = 0; 3248 PrevDecl = 0; 3249 Invalid = true; 3250 } 3251 } 3252 3253 if (!Invalid) { 3254 // If this is a use, just return the declaration we found. 3255 3256 // FIXME: In the future, return a variant or some other clue 3257 // for the consumer of this Decl to know it doesn't own it. 3258 // For our current ASTs this shouldn't be a problem, but will 3259 // need to be changed with DeclGroups. 3260 if (TK == TK_Reference) 3261 return DeclPtrTy::make(PrevDecl); 3262 3263 // Diagnose attempts to redefine a tag. 3264 if (TK == TK_Definition) { 3265 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3266 Diag(NameLoc, diag::err_redefinition) << Name; 3267 Diag(Def->getLocation(), diag::note_previous_definition); 3268 // If this is a redefinition, recover by making this 3269 // struct be anonymous, which will make any later 3270 // references get the previous definition. 3271 Name = 0; 3272 PrevDecl = 0; 3273 Invalid = true; 3274 } else { 3275 // If the type is currently being defined, complain 3276 // about a nested redefinition. 3277 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3278 if (Tag->isBeingDefined()) { 3279 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3280 Diag(PrevTagDecl->getLocation(), 3281 diag::note_previous_definition); 3282 Name = 0; 3283 PrevDecl = 0; 3284 Invalid = true; 3285 } 3286 } 3287 3288 // Okay, this is definition of a previously declared or referenced 3289 // tag PrevDecl. We're going to create a new Decl for it. 3290 } 3291 } 3292 // If we get here we have (another) forward declaration or we 3293 // have a definition. Just create a new decl. 3294 } else { 3295 // If we get here, this is a definition of a new tag type in a nested 3296 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3297 // new decl/type. We set PrevDecl to NULL so that the entities 3298 // have distinct types. 3299 PrevDecl = 0; 3300 } 3301 // If we get here, we're going to create a new Decl. If PrevDecl 3302 // is non-NULL, it's a definition of the tag declared by 3303 // PrevDecl. If it's NULL, we have a new definition. 3304 } else { 3305 // PrevDecl is a namespace, template, or anything else 3306 // that lives in the IDNS_Tag identifier namespace. 3307 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3308 // The tag name clashes with a namespace name, issue an error and 3309 // recover by making this tag be anonymous. 3310 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3311 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3312 Name = 0; 3313 PrevDecl = 0; 3314 Invalid = true; 3315 } else { 3316 // The existing declaration isn't relevant to us; we're in a 3317 // new scope, so clear out the previous declaration. 3318 PrevDecl = 0; 3319 } 3320 } 3321 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3322 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3323 // C.scope.pdecl]p5: 3324 // -- for an elaborated-type-specifier of the form 3325 // 3326 // class-key identifier 3327 // 3328 // if the elaborated-type-specifier is used in the 3329 // decl-specifier-seq or parameter-declaration-clause of a 3330 // function defined in namespace scope, the identifier is 3331 // declared as a class-name in the namespace that contains 3332 // the declaration; otherwise, except as a friend 3333 // declaration, the identifier is declared in the smallest 3334 // non-class, non-function-prototype scope that contains the 3335 // declaration. 3336 // 3337 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3338 // C structs and unions. 3339 // 3340 // GNU C also supports this behavior as part of its incomplete 3341 // enum types extension, while GNU C++ does not. 3342 // 3343 // Find the context where we'll be declaring the tag. 3344 // FIXME: We would like to maintain the current DeclContext as the 3345 // lexical context, 3346 while (SearchDC->isRecord()) 3347 SearchDC = SearchDC->getParent(); 3348 3349 // Find the scope where we'll be declaring the tag. 3350 while (S->isClassScope() || 3351 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3352 ((S->getFlags() & Scope::DeclScope) == 0) || 3353 (S->getEntity() && 3354 ((DeclContext *)S->getEntity())->isTransparentContext())) 3355 S = S->getParent(); 3356 } 3357 3358CreateNewDecl: 3359 3360 // If there is an identifier, use the location of the identifier as the 3361 // location of the decl, otherwise use the location of the struct/union 3362 // keyword. 3363 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3364 3365 // Otherwise, create a new declaration. If there is a previous 3366 // declaration of the same entity, the two will be linked via 3367 // PrevDecl. 3368 TagDecl *New; 3369 3370 if (Kind == TagDecl::TK_enum) { 3371 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3372 // enum X { A, B, C } D; D should chain to X. 3373 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3374 cast_or_null<EnumDecl>(PrevDecl)); 3375 // If this is an undefined enum, warn. 3376 if (TK != TK_Definition && !Invalid) { 3377 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3378 : diag::ext_forward_ref_enum; 3379 Diag(Loc, DK); 3380 } 3381 } else { 3382 // struct/union/class 3383 3384 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3385 // struct X { int A; } D; D should chain to X. 3386 if (getLangOptions().CPlusPlus) 3387 // FIXME: Look for a way to use RecordDecl for simple structs. 3388 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3389 cast_or_null<CXXRecordDecl>(PrevDecl)); 3390 else 3391 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3392 cast_or_null<RecordDecl>(PrevDecl)); 3393 } 3394 3395 if (Kind != TagDecl::TK_enum) { 3396 // Handle #pragma pack: if the #pragma pack stack has non-default 3397 // alignment, make up a packed attribute for this decl. These 3398 // attributes are checked when the ASTContext lays out the 3399 // structure. 3400 // 3401 // It is important for implementing the correct semantics that this 3402 // happen here (in act on tag decl). The #pragma pack stack is 3403 // maintained as a result of parser callbacks which can occur at 3404 // many points during the parsing of a struct declaration (because 3405 // the #pragma tokens are effectively skipped over during the 3406 // parsing of the struct). 3407 if (unsigned Alignment = getPragmaPackAlignment()) 3408 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3409 } 3410 3411 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3412 // C++ [dcl.typedef]p3: 3413 // [...] Similarly, in a given scope, a class or enumeration 3414 // shall not be declared with the same name as a typedef-name 3415 // that is declared in that scope and refers to a type other 3416 // than the class or enumeration itself. 3417 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3418 TypedefDecl *PrevTypedef = 0; 3419 if (Lookup.getKind() == LookupResult::Found) 3420 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3421 3422 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3423 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3424 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3425 Diag(Loc, diag::err_tag_definition_of_typedef) 3426 << Context.getTypeDeclType(New) 3427 << PrevTypedef->getUnderlyingType(); 3428 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3429 Invalid = true; 3430 } 3431 } 3432 3433 if (Invalid) 3434 New->setInvalidDecl(); 3435 3436 if (Attr) 3437 ProcessDeclAttributeList(New, Attr); 3438 3439 // If we're declaring or defining a tag in function prototype scope 3440 // in C, note that this type can only be used within the function. 3441 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3442 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3443 3444 // Set the lexical context. If the tag has a C++ scope specifier, the 3445 // lexical context will be different from the semantic context. 3446 New->setLexicalDeclContext(CurContext); 3447 3448 // Set the access specifier. 3449 SetMemberAccessSpecifier(New, PrevDecl, AS); 3450 3451 if (TK == TK_Definition) 3452 New->startDefinition(); 3453 3454 // If this has an identifier, add it to the scope stack. 3455 if (Name) { 3456 S = getNonFieldDeclScope(S); 3457 PushOnScopeChains(New, S); 3458 } else { 3459 CurContext->addDecl(Context, New); 3460 } 3461 3462 return DeclPtrTy::make(New); 3463} 3464 3465void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3466 AdjustDeclIfTemplate(TagD); 3467 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3468 3469 // Enter the tag context. 3470 PushDeclContext(S, Tag); 3471 3472 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3473 FieldCollector->StartClass(); 3474 3475 if (Record->getIdentifier()) { 3476 // C++ [class]p2: 3477 // [...] The class-name is also inserted into the scope of the 3478 // class itself; this is known as the injected-class-name. For 3479 // purposes of access checking, the injected-class-name is treated 3480 // as if it were a public member name. 3481 CXXRecordDecl *InjectedClassName 3482 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3483 CurContext, Record->getLocation(), 3484 Record->getIdentifier(), Record); 3485 InjectedClassName->setImplicit(); 3486 InjectedClassName->setAccess(AS_public); 3487 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3488 InjectedClassName->setDescribedClassTemplate(Template); 3489 PushOnScopeChains(InjectedClassName, S); 3490 assert(InjectedClassName->isInjectedClassName() && 3491 "Broken injected-class-name"); 3492 } 3493 } 3494} 3495 3496void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3497 AdjustDeclIfTemplate(TagD); 3498 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3499 3500 if (isa<CXXRecordDecl>(Tag)) 3501 FieldCollector->FinishClass(); 3502 3503 // Exit this scope of this tag's definition. 3504 PopDeclContext(); 3505 3506 // Notify the consumer that we've defined a tag. 3507 Consumer.HandleTagDeclDefinition(Tag); 3508} 3509 3510bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3511 QualType FieldTy, const Expr *BitWidth) { 3512 // C99 6.7.2.1p4 - verify the field type. 3513 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3514 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3515 // Handle incomplete types with specific error. 3516 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3517 return true; 3518 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3519 << FieldName << FieldTy << BitWidth->getSourceRange(); 3520 } 3521 3522 // If the bit-width is type- or value-dependent, don't try to check 3523 // it now. 3524 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3525 return false; 3526 3527 llvm::APSInt Value; 3528 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3529 return true; 3530 3531 // Zero-width bitfield is ok for anonymous field. 3532 if (Value == 0 && FieldName) 3533 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3534 3535 if (Value.isSigned() && Value.isNegative()) 3536 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3537 << FieldName << Value.toString(10); 3538 3539 if (!FieldTy->isDependentType()) { 3540 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3541 // FIXME: We won't need the 0 size once we check that the field type is valid. 3542 if (TypeSize && Value.getZExtValue() > TypeSize) 3543 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3544 << FieldName << (unsigned)TypeSize; 3545 } 3546 3547 return false; 3548} 3549 3550/// ActOnField - Each field of a struct/union/class is passed into this in order 3551/// to create a FieldDecl object for it. 3552Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3553 SourceLocation DeclStart, 3554 Declarator &D, ExprTy *BitfieldWidth) { 3555 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3556 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3557 AS_public); 3558 return DeclPtrTy::make(Res); 3559} 3560 3561/// HandleField - Analyze a field of a C struct or a C++ data member. 3562/// 3563FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3564 SourceLocation DeclStart, 3565 Declarator &D, Expr *BitWidth, 3566 AccessSpecifier AS) { 3567 IdentifierInfo *II = D.getIdentifier(); 3568 SourceLocation Loc = DeclStart; 3569 if (II) Loc = D.getIdentifierLoc(); 3570 3571 QualType T = GetTypeForDeclarator(D, S); 3572 if (getLangOptions().CPlusPlus) 3573 CheckExtraCXXDefaultArguments(D); 3574 3575 DiagnoseFunctionSpecifiers(D); 3576 3577 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3578 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3579 PrevDecl = 0; 3580 3581 FieldDecl *NewFD 3582 = CheckFieldDecl(II, T, Record, Loc, 3583 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3584 BitWidth, AS, PrevDecl, &D); 3585 if (NewFD->isInvalidDecl() && PrevDecl) { 3586 // Don't introduce NewFD into scope; there's already something 3587 // with the same name in the same scope. 3588 } else if (II) { 3589 PushOnScopeChains(NewFD, S); 3590 } else 3591 Record->addDecl(Context, NewFD); 3592 3593 return NewFD; 3594} 3595 3596/// \brief Build a new FieldDecl and check its well-formedness. 3597/// 3598/// This routine builds a new FieldDecl given the fields name, type, 3599/// record, etc. \p PrevDecl should refer to any previous declaration 3600/// with the same name and in the same scope as the field to be 3601/// created. 3602/// 3603/// \returns a new FieldDecl. 3604/// 3605/// \todo The Declarator argument is a hack. It will be removed once 3606FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3607 RecordDecl *Record, SourceLocation Loc, 3608 bool Mutable, Expr *BitWidth, 3609 AccessSpecifier AS, NamedDecl *PrevDecl, 3610 Declarator *D) { 3611 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3612 bool InvalidDecl = false; 3613 3614 // If we receive a broken type, recover by assuming 'int' and 3615 // marking this declaration as invalid. 3616 if (T.isNull()) { 3617 InvalidDecl = true; 3618 T = Context.IntTy; 3619 } 3620 3621 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3622 // than a variably modified type. 3623 if (T->isVariablyModifiedType()) { 3624 bool SizeIsNegative; 3625 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3626 SizeIsNegative); 3627 if (!FixedTy.isNull()) { 3628 Diag(Loc, diag::warn_illegal_constant_array_size); 3629 T = FixedTy; 3630 } else { 3631 if (SizeIsNegative) 3632 Diag(Loc, diag::err_typecheck_negative_array_size); 3633 else 3634 Diag(Loc, diag::err_typecheck_field_variable_size); 3635 T = Context.IntTy; 3636 InvalidDecl = true; 3637 } 3638 } 3639 3640 // Fields can not have abstract class types 3641 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3642 AbstractFieldType)) 3643 InvalidDecl = true; 3644 3645 // If this is declared as a bit-field, check the bit-field. 3646 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3647 InvalidDecl = true; 3648 DeleteExpr(BitWidth); 3649 BitWidth = 0; 3650 } 3651 3652 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3653 Mutable); 3654 3655 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3656 Diag(Loc, diag::err_duplicate_member) << II; 3657 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3658 NewFD->setInvalidDecl(); 3659 Record->setInvalidDecl(); 3660 } 3661 3662 if (getLangOptions().CPlusPlus && !T->isPODType()) 3663 cast<CXXRecordDecl>(Record)->setPOD(false); 3664 3665 // FIXME: We need to pass in the attributes given an AST 3666 // representation, not a parser representation. 3667 if (D) 3668 ProcessDeclAttributes(NewFD, *D); 3669 3670 if (T.isObjCGCWeak()) 3671 Diag(Loc, diag::warn_attribute_weak_on_field); 3672 3673 if (InvalidDecl) 3674 NewFD->setInvalidDecl(); 3675 3676 NewFD->setAccess(AS); 3677 3678 // C++ [dcl.init.aggr]p1: 3679 // An aggregate is an array or a class (clause 9) with [...] no 3680 // private or protected non-static data members (clause 11). 3681 // A POD must be an aggregate. 3682 if (getLangOptions().CPlusPlus && 3683 (AS == AS_private || AS == AS_protected)) { 3684 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3685 CXXRecord->setAggregate(false); 3686 CXXRecord->setPOD(false); 3687 } 3688 3689 return NewFD; 3690} 3691 3692/// TranslateIvarVisibility - Translate visibility from a token ID to an 3693/// AST enum value. 3694static ObjCIvarDecl::AccessControl 3695TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3696 switch (ivarVisibility) { 3697 default: assert(0 && "Unknown visitibility kind"); 3698 case tok::objc_private: return ObjCIvarDecl::Private; 3699 case tok::objc_public: return ObjCIvarDecl::Public; 3700 case tok::objc_protected: return ObjCIvarDecl::Protected; 3701 case tok::objc_package: return ObjCIvarDecl::Package; 3702 } 3703} 3704 3705/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3706/// in order to create an IvarDecl object for it. 3707Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3708 SourceLocation DeclStart, 3709 Declarator &D, ExprTy *BitfieldWidth, 3710 tok::ObjCKeywordKind Visibility) { 3711 3712 IdentifierInfo *II = D.getIdentifier(); 3713 Expr *BitWidth = (Expr*)BitfieldWidth; 3714 SourceLocation Loc = DeclStart; 3715 if (II) Loc = D.getIdentifierLoc(); 3716 3717 // FIXME: Unnamed fields can be handled in various different ways, for 3718 // example, unnamed unions inject all members into the struct namespace! 3719 3720 QualType T = GetTypeForDeclarator(D, S); 3721 bool InvalidDecl = false; 3722 if (T.isNull()) { 3723 InvalidDecl = true; 3724 T = Context.IntTy; 3725 } 3726 3727 if (BitWidth) { 3728 // 6.7.2.1p3, 6.7.2.1p4 3729 if (VerifyBitField(Loc, II, T, BitWidth)) { 3730 InvalidDecl = true; 3731 DeleteExpr(BitWidth); 3732 BitWidth = 0; 3733 } 3734 } else { 3735 // Not a bitfield. 3736 3737 // validate II. 3738 3739 } 3740 3741 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3742 // than a variably modified type. 3743 if (T->isVariablyModifiedType()) { 3744 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3745 InvalidDecl = true; 3746 } 3747 3748 // Get the visibility (access control) for this ivar. 3749 ObjCIvarDecl::AccessControl ac = 3750 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3751 : ObjCIvarDecl::None; 3752 3753 // Construct the decl. 3754 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3755 (Expr *)BitfieldWidth); 3756 3757 if (II) { 3758 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3759 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3760 && !isa<TagDecl>(PrevDecl)) { 3761 Diag(Loc, diag::err_duplicate_member) << II; 3762 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3763 NewID->setInvalidDecl(); 3764 } 3765 } 3766 3767 // Process attributes attached to the ivar. 3768 ProcessDeclAttributes(NewID, D); 3769 3770 if (D.getInvalidType() || InvalidDecl) 3771 NewID->setInvalidDecl(); 3772 3773 if (II) { 3774 // FIXME: When interfaces are DeclContexts, we'll need to add 3775 // these to the interface. 3776 S->AddDecl(DeclPtrTy::make(NewID)); 3777 IdResolver.AddDecl(NewID); 3778 } 3779 3780 return DeclPtrTy::make(NewID); 3781} 3782 3783void Sema::ActOnFields(Scope* S, 3784 SourceLocation RecLoc, DeclPtrTy RecDecl, 3785 DeclPtrTy *Fields, unsigned NumFields, 3786 SourceLocation LBrac, SourceLocation RBrac, 3787 AttributeList *Attr) { 3788 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3789 assert(EnclosingDecl && "missing record or interface decl"); 3790 3791 // If the decl this is being inserted into is invalid, then it may be a 3792 // redeclaration or some other bogus case. Don't try to add fields to it. 3793 if (EnclosingDecl->isInvalidDecl()) { 3794 // FIXME: Deallocate fields? 3795 return; 3796 } 3797 3798 3799 // Verify that all the fields are okay. 3800 unsigned NumNamedMembers = 0; 3801 llvm::SmallVector<FieldDecl*, 32> RecFields; 3802 3803 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3804 for (unsigned i = 0; i != NumFields; ++i) { 3805 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3806 3807 // Get the type for the field. 3808 Type *FDTy = FD->getType().getTypePtr(); 3809 3810 if (!FD->isAnonymousStructOrUnion()) { 3811 // Remember all fields written by the user. 3812 RecFields.push_back(FD); 3813 } 3814 3815 // If the field is already invalid for some reason, don't emit more 3816 // diagnostics about it. 3817 if (FD->isInvalidDecl()) 3818 continue; 3819 3820 // C99 6.7.2.1p2: 3821 // A structure or union shall not contain a member with 3822 // incomplete or function type (hence, a structure shall not 3823 // contain an instance of itself, but may contain a pointer to 3824 // an instance of itself), except that the last member of a 3825 // structure with more than one named member may have incomplete 3826 // array type; such a structure (and any union containing, 3827 // possibly recursively, a member that is such a structure) 3828 // shall not be a member of a structure or an element of an 3829 // array. 3830 if (FDTy->isFunctionType()) { 3831 // Field declared as a function. 3832 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3833 << FD->getDeclName(); 3834 FD->setInvalidDecl(); 3835 EnclosingDecl->setInvalidDecl(); 3836 continue; 3837 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3838 Record && Record->isStruct()) { 3839 // Flexible array member. 3840 if (NumNamedMembers < 1) { 3841 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3842 << FD->getDeclName(); 3843 FD->setInvalidDecl(); 3844 EnclosingDecl->setInvalidDecl(); 3845 continue; 3846 } 3847 // Okay, we have a legal flexible array member at the end of the struct. 3848 if (Record) 3849 Record->setHasFlexibleArrayMember(true); 3850 } else if (!FDTy->isDependentType() && 3851 RequireCompleteType(FD->getLocation(), FD->getType(), 3852 diag::err_field_incomplete)) { 3853 // Incomplete type 3854 FD->setInvalidDecl(); 3855 EnclosingDecl->setInvalidDecl(); 3856 continue; 3857 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3858 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3859 // If this is a member of a union, then entire union becomes "flexible". 3860 if (Record && Record->isUnion()) { 3861 Record->setHasFlexibleArrayMember(true); 3862 } else { 3863 // If this is a struct/class and this is not the last element, reject 3864 // it. Note that GCC supports variable sized arrays in the middle of 3865 // structures. 3866 if (i != NumFields-1) 3867 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3868 << FD->getDeclName(); 3869 else { 3870 // We support flexible arrays at the end of structs in 3871 // other structs as an extension. 3872 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3873 << FD->getDeclName(); 3874 if (Record) 3875 Record->setHasFlexibleArrayMember(true); 3876 } 3877 } 3878 } 3879 } else if (FDTy->isObjCInterfaceType()) { 3880 /// A field cannot be an Objective-c object 3881 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3882 FD->setInvalidDecl(); 3883 EnclosingDecl->setInvalidDecl(); 3884 continue; 3885 } 3886 // Keep track of the number of named members. 3887 if (FD->getIdentifier()) 3888 ++NumNamedMembers; 3889 } 3890 3891 // Okay, we successfully defined 'Record'. 3892 if (Record) { 3893 Record->completeDefinition(Context); 3894 } else { 3895 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3896 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3897 ID->setIVarList(ClsFields, RecFields.size(), Context); 3898 ID->setLocEnd(RBrac); 3899 3900 // Must enforce the rule that ivars in the base classes may not be 3901 // duplicates. 3902 if (ID->getSuperClass()) { 3903 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3904 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3905 ObjCIvarDecl* Ivar = (*IVI); 3906 IdentifierInfo *II = Ivar->getIdentifier(); 3907 ObjCIvarDecl* prevIvar = 3908 ID->getSuperClass()->lookupInstanceVariable(Context, II); 3909 if (prevIvar) { 3910 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3911 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3912 } 3913 } 3914 } 3915 } else if (ObjCImplementationDecl *IMPDecl = 3916 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3917 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3918 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3919 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3920 } 3921 } 3922 3923 if (Attr) 3924 ProcessDeclAttributeList(Record, Attr); 3925} 3926 3927EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 3928 EnumConstantDecl *LastEnumConst, 3929 SourceLocation IdLoc, 3930 IdentifierInfo *Id, 3931 ExprArg val) { 3932 Expr *Val = (Expr *)val.get(); 3933 3934 llvm::APSInt EnumVal(32); 3935 QualType EltTy; 3936 if (Val && !Val->isTypeDependent()) { 3937 // Make sure to promote the operand type to int. 3938 UsualUnaryConversions(Val); 3939 if (Val != val.get()) { 3940 val.release(); 3941 val = Val; 3942 } 3943 3944 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3945 SourceLocation ExpLoc; 3946 if (!Val->isValueDependent() && 3947 VerifyIntegerConstantExpression(Val, &EnumVal)) { 3948 Val = 0; 3949 } else { 3950 EltTy = Val->getType(); 3951 } 3952 } 3953 3954 if (!Val) { 3955 if (LastEnumConst) { 3956 // Assign the last value + 1. 3957 EnumVal = LastEnumConst->getInitVal(); 3958 ++EnumVal; 3959 3960 // Check for overflow on increment. 3961 if (EnumVal < LastEnumConst->getInitVal()) 3962 Diag(IdLoc, diag::warn_enum_value_overflow); 3963 3964 EltTy = LastEnumConst->getType(); 3965 } else { 3966 // First value, set to zero. 3967 EltTy = Context.IntTy; 3968 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3969 } 3970 } 3971 3972 val.release(); 3973 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 3974 Val, EnumVal); 3975} 3976 3977 3978Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 3979 DeclPtrTy lastEnumConst, 3980 SourceLocation IdLoc, 3981 IdentifierInfo *Id, 3982 SourceLocation EqualLoc, ExprTy *val) { 3983 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 3984 EnumConstantDecl *LastEnumConst = 3985 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 3986 Expr *Val = static_cast<Expr*>(val); 3987 3988 // The scope passed in may not be a decl scope. Zip up the scope tree until 3989 // we find one that is. 3990 S = getNonFieldDeclScope(S); 3991 3992 // Verify that there isn't already something declared with this name in this 3993 // scope. 3994 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3995 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3996 // Maybe we will complain about the shadowed template parameter. 3997 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3998 // Just pretend that we didn't see the previous declaration. 3999 PrevDecl = 0; 4000 } 4001 4002 if (PrevDecl) { 4003 // When in C++, we may get a TagDecl with the same name; in this case the 4004 // enum constant will 'hide' the tag. 4005 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4006 "Received TagDecl when not in C++!"); 4007 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4008 if (isa<EnumConstantDecl>(PrevDecl)) 4009 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4010 else 4011 Diag(IdLoc, diag::err_redefinition) << Id; 4012 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4013 if (Val) Val->Destroy(Context); 4014 return DeclPtrTy(); 4015 } 4016 } 4017 4018 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4019 IdLoc, Id, Owned(Val)); 4020 4021 // Register this decl in the current scope stack. 4022 if (New) 4023 PushOnScopeChains(New, S); 4024 4025 return DeclPtrTy::make(New); 4026} 4027 4028// FIXME: For consistency with ActOnFields(), we should have the parser 4029// pass in the source location for the left/right braces. 4030void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4031 DeclPtrTy *Elements, unsigned NumElements) { 4032 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4033 QualType EnumType = Context.getTypeDeclType(Enum); 4034 4035 // TODO: If the result value doesn't fit in an int, it must be a long or long 4036 // long value. ISO C does not support this, but GCC does as an extension, 4037 // emit a warning. 4038 unsigned IntWidth = Context.Target.getIntWidth(); 4039 4040 // Verify that all the values are okay, compute the size of the values, and 4041 // reverse the list. 4042 unsigned NumNegativeBits = 0; 4043 unsigned NumPositiveBits = 0; 4044 4045 // Keep track of whether all elements have type int. 4046 bool AllElementsInt = true; 4047 4048 for (unsigned i = 0; i != NumElements; ++i) { 4049 EnumConstantDecl *ECD = 4050 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4051 if (!ECD) continue; // Already issued a diagnostic. 4052 4053 // If the enum value doesn't fit in an int, emit an extension warning. 4054 const llvm::APSInt &InitVal = ECD->getInitVal(); 4055 assert(InitVal.getBitWidth() >= IntWidth && 4056 "Should have promoted value to int"); 4057 if (InitVal.getBitWidth() > IntWidth) { 4058 llvm::APSInt V(InitVal); 4059 V.trunc(IntWidth); 4060 V.extend(InitVal.getBitWidth()); 4061 if (V != InitVal) 4062 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4063 << InitVal.toString(10); 4064 } 4065 4066 // Keep track of the size of positive and negative values. 4067 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4068 NumPositiveBits = std::max(NumPositiveBits, 4069 (unsigned)InitVal.getActiveBits()); 4070 else 4071 NumNegativeBits = std::max(NumNegativeBits, 4072 (unsigned)InitVal.getMinSignedBits()); 4073 4074 // Keep track of whether every enum element has type int (very commmon). 4075 if (AllElementsInt) 4076 AllElementsInt = ECD->getType() == Context.IntTy; 4077 } 4078 4079 // Figure out the type that should be used for this enum. 4080 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4081 QualType BestType; 4082 unsigned BestWidth; 4083 4084 if (NumNegativeBits) { 4085 // If there is a negative value, figure out the smallest integer type (of 4086 // int/long/longlong) that fits. 4087 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4088 BestType = Context.IntTy; 4089 BestWidth = IntWidth; 4090 } else { 4091 BestWidth = Context.Target.getLongWidth(); 4092 4093 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4094 BestType = Context.LongTy; 4095 else { 4096 BestWidth = Context.Target.getLongLongWidth(); 4097 4098 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4099 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4100 BestType = Context.LongLongTy; 4101 } 4102 } 4103 } else { 4104 // If there is no negative value, figure out which of uint, ulong, ulonglong 4105 // fits. 4106 if (NumPositiveBits <= IntWidth) { 4107 BestType = Context.UnsignedIntTy; 4108 BestWidth = IntWidth; 4109 } else if (NumPositiveBits <= 4110 (BestWidth = Context.Target.getLongWidth())) { 4111 BestType = Context.UnsignedLongTy; 4112 } else { 4113 BestWidth = Context.Target.getLongLongWidth(); 4114 assert(NumPositiveBits <= BestWidth && 4115 "How could an initializer get larger than ULL?"); 4116 BestType = Context.UnsignedLongLongTy; 4117 } 4118 } 4119 4120 // Loop over all of the enumerator constants, changing their types to match 4121 // the type of the enum if needed. 4122 for (unsigned i = 0; i != NumElements; ++i) { 4123 EnumConstantDecl *ECD = 4124 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4125 if (!ECD) continue; // Already issued a diagnostic. 4126 4127 // Standard C says the enumerators have int type, but we allow, as an 4128 // extension, the enumerators to be larger than int size. If each 4129 // enumerator value fits in an int, type it as an int, otherwise type it the 4130 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4131 // that X has type 'int', not 'unsigned'. 4132 if (ECD->getType() == Context.IntTy) { 4133 // Make sure the init value is signed. 4134 llvm::APSInt IV = ECD->getInitVal(); 4135 IV.setIsSigned(true); 4136 ECD->setInitVal(IV); 4137 4138 if (getLangOptions().CPlusPlus) 4139 // C++ [dcl.enum]p4: Following the closing brace of an 4140 // enum-specifier, each enumerator has the type of its 4141 // enumeration. 4142 ECD->setType(EnumType); 4143 continue; // Already int type. 4144 } 4145 4146 // Determine whether the value fits into an int. 4147 llvm::APSInt InitVal = ECD->getInitVal(); 4148 bool FitsInInt; 4149 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4150 FitsInInt = InitVal.getActiveBits() < IntWidth; 4151 else 4152 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4153 4154 // If it fits into an integer type, force it. Otherwise force it to match 4155 // the enum decl type. 4156 QualType NewTy; 4157 unsigned NewWidth; 4158 bool NewSign; 4159 if (FitsInInt) { 4160 NewTy = Context.IntTy; 4161 NewWidth = IntWidth; 4162 NewSign = true; 4163 } else if (ECD->getType() == BestType) { 4164 // Already the right type! 4165 if (getLangOptions().CPlusPlus) 4166 // C++ [dcl.enum]p4: Following the closing brace of an 4167 // enum-specifier, each enumerator has the type of its 4168 // enumeration. 4169 ECD->setType(EnumType); 4170 continue; 4171 } else { 4172 NewTy = BestType; 4173 NewWidth = BestWidth; 4174 NewSign = BestType->isSignedIntegerType(); 4175 } 4176 4177 // Adjust the APSInt value. 4178 InitVal.extOrTrunc(NewWidth); 4179 InitVal.setIsSigned(NewSign); 4180 ECD->setInitVal(InitVal); 4181 4182 // Adjust the Expr initializer and type. 4183 if (ECD->getInitExpr()) 4184 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4185 /*isLvalue=*/false)); 4186 if (getLangOptions().CPlusPlus) 4187 // C++ [dcl.enum]p4: Following the closing brace of an 4188 // enum-specifier, each enumerator has the type of its 4189 // enumeration. 4190 ECD->setType(EnumType); 4191 else 4192 ECD->setType(NewTy); 4193 } 4194 4195 Enum->completeDefinition(Context, BestType); 4196} 4197 4198Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4199 ExprArg expr) { 4200 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4201 4202 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4203 Loc, AsmString)); 4204} 4205 4206