SemaDecl.cpp revision 6a83969807530ebdb24ed97917eb644a4e724b14
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(DeclTy *d) { 36 Decl *D = static_cast<Decl *>(d); 37 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 38 return DN->getQualifiedNameAsString(); 39 return ""; 40} 41 42/// \brief If the identifier refers to a type name within this scope, 43/// return the declaration of that type. 44/// 45/// This routine performs ordinary name lookup of the identifier II 46/// within the given scope, with optional C++ scope specifier SS, to 47/// determine whether the name refers to a type. If so, returns an 48/// opaque pointer (actually a QualType) corresponding to that 49/// type. Otherwise, returns NULL. 50/// 51/// If name lookup results in an ambiguity, this routine will complain 52/// and then return NULL. 53Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 54 Scope *S, const CXXScopeSpec *SS) { 55 NamedDecl *IIDecl = 0; 56 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 57 false, false); 58 switch (Result.getKind()) { 59 case LookupResult::NotFound: 60 case LookupResult::FoundOverloaded: 61 return 0; 62 63 case LookupResult::AmbiguousBaseSubobjectTypes: 64 case LookupResult::AmbiguousBaseSubobjects: 65 case LookupResult::AmbiguousReference: 66 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 67 return 0; 68 69 case LookupResult::Found: 70 IIDecl = Result.getAsDecl(); 71 break; 72 } 73 74 if (IIDecl) { 75 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 76 // Check whether we can use this type 77 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 78 79 return Context.getTypeDeclType(TD).getAsOpaquePtr(); 80 } 81 82 if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 83 // Check whether we can use this interface. 84 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 85 86 return Context.getObjCInterfaceType(IDecl).getAsOpaquePtr(); 87 } 88 89 // Otherwise, could be a variable, function etc. 90 } 91 return 0; 92} 93 94DeclContext *Sema::getContainingDC(DeclContext *DC) { 95 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 96 // A C++ out-of-line method will return to the file declaration context. 97 if (MD->isOutOfLineDefinition()) 98 return MD->getLexicalDeclContext(); 99 100 // A C++ inline method is parsed *after* the topmost class it was declared 101 // in is fully parsed (it's "complete"). 102 // The parsing of a C++ inline method happens at the declaration context of 103 // the topmost (non-nested) class it is lexically declared in. 104 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 105 DC = MD->getParent(); 106 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 107 DC = RD; 108 109 // Return the declaration context of the topmost class the inline method is 110 // declared in. 111 return DC; 112 } 113 114 if (isa<ObjCMethodDecl>(DC)) 115 return Context.getTranslationUnitDecl(); 116 117 return DC->getLexicalParent(); 118} 119 120void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 121 assert(getContainingDC(DC) == CurContext && 122 "The next DeclContext should be lexically contained in the current one."); 123 CurContext = DC; 124 S->setEntity(DC); 125} 126 127void Sema::PopDeclContext() { 128 assert(CurContext && "DeclContext imbalance!"); 129 130 CurContext = getContainingDC(CurContext); 131} 132 133/// \brief Determine whether we allow overloading of the function 134/// PrevDecl with another declaration. 135/// 136/// This routine determines whether overloading is possible, not 137/// whether some new function is actually an overload. It will return 138/// true in C++ (where we can always provide overloads) or, as an 139/// extension, in C when the previous function is already an 140/// overloaded function declaration or has the "overloadable" 141/// attribute. 142static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 143 if (Context.getLangOptions().CPlusPlus) 144 return true; 145 146 if (isa<OverloadedFunctionDecl>(PrevDecl)) 147 return true; 148 149 return PrevDecl->getAttr<OverloadableAttr>() != 0; 150} 151 152/// Add this decl to the scope shadowed decl chains. 153void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 154 // Move up the scope chain until we find the nearest enclosing 155 // non-transparent context. The declaration will be introduced into this 156 // scope. 157 while (S->getEntity() && 158 ((DeclContext *)S->getEntity())->isTransparentContext()) 159 S = S->getParent(); 160 161 S->AddDecl(D); 162 163 // Add scoped declarations into their context, so that they can be 164 // found later. Declarations without a context won't be inserted 165 // into any context. 166 CurContext->addDecl(D); 167 168 // C++ [basic.scope]p4: 169 // -- exactly one declaration shall declare a class name or 170 // enumeration name that is not a typedef name and the other 171 // declarations shall all refer to the same object or 172 // enumerator, or all refer to functions and function templates; 173 // in this case the class name or enumeration name is hidden. 174 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 175 // We are pushing the name of a tag (enum or class). 176 if (CurContext->getLookupContext() 177 == TD->getDeclContext()->getLookupContext()) { 178 // We're pushing the tag into the current context, which might 179 // require some reshuffling in the identifier resolver. 180 IdentifierResolver::iterator 181 I = IdResolver.begin(TD->getDeclName()), 182 IEnd = IdResolver.end(); 183 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 184 NamedDecl *PrevDecl = *I; 185 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 186 PrevDecl = *I, ++I) { 187 if (TD->declarationReplaces(*I)) { 188 // This is a redeclaration. Remove it from the chain and 189 // break out, so that we'll add in the shadowed 190 // declaration. 191 S->RemoveDecl(*I); 192 if (PrevDecl == *I) { 193 IdResolver.RemoveDecl(*I); 194 IdResolver.AddDecl(TD); 195 return; 196 } else { 197 IdResolver.RemoveDecl(*I); 198 break; 199 } 200 } 201 } 202 203 // There is already a declaration with the same name in the same 204 // scope, which is not a tag declaration. It must be found 205 // before we find the new declaration, so insert the new 206 // declaration at the end of the chain. 207 IdResolver.AddShadowedDecl(TD, PrevDecl); 208 209 return; 210 } 211 } 212 } else if (isa<FunctionDecl>(D) && 213 AllowOverloadingOfFunction(D, Context)) { 214 // We are pushing the name of a function, which might be an 215 // overloaded name. 216 FunctionDecl *FD = cast<FunctionDecl>(D); 217 IdentifierResolver::iterator Redecl 218 = std::find_if(IdResolver.begin(FD->getDeclName()), 219 IdResolver.end(), 220 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 221 FD)); 222 if (Redecl != IdResolver.end() && S->isDeclScope(*Redecl)) { 223 // There is already a declaration of a function on our 224 // IdResolver chain. Replace it with this declaration. 225 S->RemoveDecl(*Redecl); 226 IdResolver.RemoveDecl(*Redecl); 227 } 228 } 229 230 IdResolver.AddDecl(D); 231} 232 233void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 234 if (S->decl_empty()) return; 235 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 236 "Scope shouldn't contain decls!"); 237 238 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 239 I != E; ++I) { 240 Decl *TmpD = static_cast<Decl*>(*I); 241 assert(TmpD && "This decl didn't get pushed??"); 242 243 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 244 NamedDecl *D = cast<NamedDecl>(TmpD); 245 246 if (!D->getDeclName()) continue; 247 248 // Remove this name from our lexical scope. 249 IdResolver.RemoveDecl(D); 250 } 251} 252 253/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 254/// return 0 if one not found. 255ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 256 // The third "scope" argument is 0 since we aren't enabling lazy built-in 257 // creation from this context. 258 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 259 260 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 261} 262 263/// getNonFieldDeclScope - Retrieves the innermost scope, starting 264/// from S, where a non-field would be declared. This routine copes 265/// with the difference between C and C++ scoping rules in structs and 266/// unions. For example, the following code is well-formed in C but 267/// ill-formed in C++: 268/// @code 269/// struct S6 { 270/// enum { BAR } e; 271/// }; 272/// 273/// void test_S6() { 274/// struct S6 a; 275/// a.e = BAR; 276/// } 277/// @endcode 278/// For the declaration of BAR, this routine will return a different 279/// scope. The scope S will be the scope of the unnamed enumeration 280/// within S6. In C++, this routine will return the scope associated 281/// with S6, because the enumeration's scope is a transparent 282/// context but structures can contain non-field names. In C, this 283/// routine will return the translation unit scope, since the 284/// enumeration's scope is a transparent context and structures cannot 285/// contain non-field names. 286Scope *Sema::getNonFieldDeclScope(Scope *S) { 287 while (((S->getFlags() & Scope::DeclScope) == 0) || 288 (S->getEntity() && 289 ((DeclContext *)S->getEntity())->isTransparentContext()) || 290 (S->isClassScope() && !getLangOptions().CPlusPlus)) 291 S = S->getParent(); 292 return S; 293} 294 295void Sema::InitBuiltinVaListType() { 296 if (!Context.getBuiltinVaListType().isNull()) 297 return; 298 299 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 300 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 301 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 302 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 303} 304 305/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 306/// file scope. lazily create a decl for it. ForRedeclaration is true 307/// if we're creating this built-in in anticipation of redeclaring the 308/// built-in. 309NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 310 Scope *S, bool ForRedeclaration, 311 SourceLocation Loc) { 312 Builtin::ID BID = (Builtin::ID)bid; 313 314 if (Context.BuiltinInfo.hasVAListUse(BID)) 315 InitBuiltinVaListType(); 316 317 Builtin::Context::GetBuiltinTypeError Error; 318 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 319 switch (Error) { 320 case Builtin::Context::GE_None: 321 // Okay 322 break; 323 324 case Builtin::Context::GE_Missing_FILE: 325 if (ForRedeclaration) 326 Diag(Loc, diag::err_implicit_decl_requires_stdio) 327 << Context.BuiltinInfo.GetName(BID); 328 return 0; 329 } 330 331 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 332 Diag(Loc, diag::ext_implicit_lib_function_decl) 333 << Context.BuiltinInfo.GetName(BID) 334 << R; 335 if (Context.BuiltinInfo.getHeaderName(BID) && 336 Diags.getDiagnosticMapping(diag::ext_implicit_lib_function_decl) 337 != diag::MAP_IGNORE) 338 Diag(Loc, diag::note_please_include_header) 339 << Context.BuiltinInfo.getHeaderName(BID) 340 << Context.BuiltinInfo.GetName(BID); 341 } 342 343 FunctionDecl *New = FunctionDecl::Create(Context, 344 Context.getTranslationUnitDecl(), 345 Loc, II, R, 346 FunctionDecl::Extern, false, 347 /*hasPrototype=*/true); 348 New->setImplicit(); 349 350 // Create Decl objects for each parameter, adding them to the 351 // FunctionDecl. 352 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 353 llvm::SmallVector<ParmVarDecl*, 16> Params; 354 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 355 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 356 FT->getArgType(i), VarDecl::None, 0)); 357 New->setParams(Context, &Params[0], Params.size()); 358 } 359 360 AddKnownFunctionAttributes(New); 361 362 // TUScope is the translation-unit scope to insert this function into. 363 // FIXME: This is hideous. We need to teach PushOnScopeChains to 364 // relate Scopes to DeclContexts, and probably eliminate CurContext 365 // entirely, but we're not there yet. 366 DeclContext *SavedContext = CurContext; 367 CurContext = Context.getTranslationUnitDecl(); 368 PushOnScopeChains(New, TUScope); 369 CurContext = SavedContext; 370 return New; 371} 372 373/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 374/// everything from the standard library is defined. 375NamespaceDecl *Sema::GetStdNamespace() { 376 if (!StdNamespace) { 377 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 378 DeclContext *Global = Context.getTranslationUnitDecl(); 379 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 380 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 381 } 382 return StdNamespace; 383} 384 385/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 386/// same name and scope as a previous declaration 'Old'. Figure out 387/// how to resolve this situation, merging decls or emitting 388/// diagnostics as appropriate. Returns true if there was an error, 389/// false otherwise. 390/// 391bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 392 bool objc_types = false; 393 // Allow multiple definitions for ObjC built-in typedefs. 394 // FIXME: Verify the underlying types are equivalent! 395 if (getLangOptions().ObjC1) { 396 const IdentifierInfo *TypeID = New->getIdentifier(); 397 switch (TypeID->getLength()) { 398 default: break; 399 case 2: 400 if (!TypeID->isStr("id")) 401 break; 402 Context.setObjCIdType(New); 403 objc_types = true; 404 break; 405 case 5: 406 if (!TypeID->isStr("Class")) 407 break; 408 Context.setObjCClassType(New); 409 objc_types = true; 410 return false; 411 case 3: 412 if (!TypeID->isStr("SEL")) 413 break; 414 Context.setObjCSelType(New); 415 objc_types = true; 416 return false; 417 case 8: 418 if (!TypeID->isStr("Protocol")) 419 break; 420 Context.setObjCProtoType(New->getUnderlyingType()); 421 objc_types = true; 422 return false; 423 } 424 // Fall through - the typedef name was not a builtin type. 425 } 426 // Verify the old decl was also a type. 427 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 428 if (!Old) { 429 Diag(New->getLocation(), diag::err_redefinition_different_kind) 430 << New->getDeclName(); 431 if (!objc_types) 432 Diag(OldD->getLocation(), diag::note_previous_definition); 433 return true; 434 } 435 436 // Determine the "old" type we'll use for checking and diagnostics. 437 QualType OldType; 438 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 439 OldType = OldTypedef->getUnderlyingType(); 440 else 441 OldType = Context.getTypeDeclType(Old); 442 443 // If the typedef types are not identical, reject them in all languages and 444 // with any extensions enabled. 445 446 if (OldType != New->getUnderlyingType() && 447 Context.getCanonicalType(OldType) != 448 Context.getCanonicalType(New->getUnderlyingType())) { 449 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 450 << New->getUnderlyingType() << OldType; 451 if (!objc_types) 452 Diag(Old->getLocation(), diag::note_previous_definition); 453 return true; 454 } 455 if (objc_types) return false; 456 if (getLangOptions().Microsoft) return false; 457 458 // C++ [dcl.typedef]p2: 459 // In a given non-class scope, a typedef specifier can be used to 460 // redefine the name of any type declared in that scope to refer 461 // to the type to which it already refers. 462 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 463 return false; 464 465 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 466 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 467 // *either* declaration is in a system header. The code below implements 468 // this adhoc compatibility rule. FIXME: The following code will not 469 // work properly when compiling ".i" files (containing preprocessed output). 470 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 471 SourceManager &SrcMgr = Context.getSourceManager(); 472 if (SrcMgr.isInSystemHeader(Old->getLocation())) 473 return false; 474 if (SrcMgr.isInSystemHeader(New->getLocation())) 475 return false; 476 } 477 478 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 479 Diag(Old->getLocation(), diag::note_previous_definition); 480 return true; 481} 482 483/// DeclhasAttr - returns true if decl Declaration already has the target 484/// attribute. 485static bool DeclHasAttr(const Decl *decl, const Attr *target) { 486 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 487 if (attr->getKind() == target->getKind()) 488 return true; 489 490 return false; 491} 492 493/// MergeAttributes - append attributes from the Old decl to the New one. 494static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 495 Attr *attr = const_cast<Attr*>(Old->getAttrs()); 496 497 while (attr) { 498 Attr *tmp = attr; 499 attr = attr->getNext(); 500 501 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 502 tmp->setInherited(true); 503 New->addAttr(tmp); 504 } else { 505 tmp->setNext(0); 506 tmp->Destroy(C); 507 } 508 } 509 510 Old->invalidateAttrs(); 511} 512 513/// Used in MergeFunctionDecl to keep track of function parameters in 514/// C. 515struct GNUCompatibleParamWarning { 516 ParmVarDecl *OldParm; 517 ParmVarDecl *NewParm; 518 QualType PromotedType; 519}; 520 521/// MergeFunctionDecl - We just parsed a function 'New' from 522/// declarator D which has the same name and scope as a previous 523/// declaration 'Old'. Figure out how to resolve this situation, 524/// merging decls or emitting diagnostics as appropriate. 525/// 526/// In C++, New and Old must be declarations that are not 527/// overloaded. Use IsOverload to determine whether New and Old are 528/// overloaded, and to select the Old declaration that New should be 529/// merged with. 530/// 531/// Returns true if there was an error, false otherwise. 532bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 533 assert(!isa<OverloadedFunctionDecl>(OldD) && 534 "Cannot merge with an overloaded function declaration"); 535 536 // Verify the old decl was also a function. 537 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 538 if (!Old) { 539 Diag(New->getLocation(), diag::err_redefinition_different_kind) 540 << New->getDeclName(); 541 Diag(OldD->getLocation(), diag::note_previous_definition); 542 return true; 543 } 544 545 // Determine whether the previous declaration was a definition, 546 // implicit declaration, or a declaration. 547 diag::kind PrevDiag; 548 if (Old->isThisDeclarationADefinition()) 549 PrevDiag = diag::note_previous_definition; 550 else if (Old->isImplicit()) 551 PrevDiag = diag::note_previous_implicit_declaration; 552 else 553 PrevDiag = diag::note_previous_declaration; 554 555 QualType OldQType = Context.getCanonicalType(Old->getType()); 556 QualType NewQType = Context.getCanonicalType(New->getType()); 557 558 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 559 New->getStorageClass() == FunctionDecl::Static && 560 Old->getStorageClass() != FunctionDecl::Static) { 561 Diag(New->getLocation(), diag::err_static_non_static) 562 << New; 563 Diag(Old->getLocation(), PrevDiag); 564 return true; 565 } 566 567 if (getLangOptions().CPlusPlus) { 568 // (C++98 13.1p2): 569 // Certain function declarations cannot be overloaded: 570 // -- Function declarations that differ only in the return type 571 // cannot be overloaded. 572 QualType OldReturnType 573 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 574 QualType NewReturnType 575 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 576 if (OldReturnType != NewReturnType) { 577 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 578 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 579 return true; 580 } 581 582 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 583 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 584 if (OldMethod && NewMethod) { 585 // -- Member function declarations with the same name and the 586 // same parameter types cannot be overloaded if any of them 587 // is a static member function declaration. 588 if (OldMethod->isStatic() || NewMethod->isStatic()) { 589 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 590 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 591 return true; 592 } 593 594 // C++ [class.mem]p1: 595 // [...] A member shall not be declared twice in the 596 // member-specification, except that a nested class or member 597 // class template can be declared and then later defined. 598 if (OldMethod->getLexicalDeclContext() == 599 NewMethod->getLexicalDeclContext()) { 600 unsigned NewDiag; 601 if (isa<CXXConstructorDecl>(OldMethod)) 602 NewDiag = diag::err_constructor_redeclared; 603 else if (isa<CXXDestructorDecl>(NewMethod)) 604 NewDiag = diag::err_destructor_redeclared; 605 else if (isa<CXXConversionDecl>(NewMethod)) 606 NewDiag = diag::err_conv_function_redeclared; 607 else 608 NewDiag = diag::err_member_redeclared; 609 610 Diag(New->getLocation(), NewDiag); 611 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 612 } 613 } 614 615 // (C++98 8.3.5p3): 616 // All declarations for a function shall agree exactly in both the 617 // return type and the parameter-type-list. 618 if (OldQType == NewQType) 619 return MergeCompatibleFunctionDecls(New, Old); 620 621 // Fall through for conflicting redeclarations and redefinitions. 622 } 623 624 // C: Function types need to be compatible, not identical. This handles 625 // duplicate function decls like "void f(int); void f(enum X);" properly. 626 if (!getLangOptions().CPlusPlus && 627 Context.typesAreCompatible(OldQType, NewQType)) { 628 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 629 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 630 const FunctionProtoType *OldProto = 0; 631 if (isa<FunctionNoProtoType>(NewFuncType) && 632 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 633 // The old declaration provided a function prototype, but the 634 // new declaration does not. Merge in the prototype. 635 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 636 OldProto->arg_type_end()); 637 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 638 &ParamTypes[0], ParamTypes.size(), 639 OldProto->isVariadic(), 640 OldProto->getTypeQuals()); 641 New->setType(NewQType); 642 New->setInheritedPrototype(); 643 644 // Synthesize a parameter for each argument type. 645 llvm::SmallVector<ParmVarDecl*, 16> Params; 646 for (FunctionProtoType::arg_type_iterator 647 ParamType = OldProto->arg_type_begin(), 648 ParamEnd = OldProto->arg_type_end(); 649 ParamType != ParamEnd; ++ParamType) { 650 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 651 SourceLocation(), 0, 652 *ParamType, VarDecl::None, 653 0); 654 Param->setImplicit(); 655 Params.push_back(Param); 656 } 657 658 New->setParams(Context, &Params[0], Params.size()); 659 } 660 661 return MergeCompatibleFunctionDecls(New, Old); 662 } 663 664 // GNU C permits a K&R definition to follow a prototype declaration 665 // if the declared types of the parameters in the K&R definition 666 // match the types in the prototype declaration, even when the 667 // promoted types of the parameters from the K&R definition differ 668 // from the types in the prototype. GCC then keeps the types from 669 // the prototype. 670 if (!getLangOptions().CPlusPlus && 671 !getLangOptions().NoExtensions && 672 Old->hasPrototype() && !New->hasPrototype() && 673 New->getType()->getAsFunctionProtoType() && 674 Old->getNumParams() == New->getNumParams()) { 675 llvm::SmallVector<QualType, 16> ArgTypes; 676 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 677 const FunctionProtoType *OldProto 678 = Old->getType()->getAsFunctionProtoType(); 679 const FunctionProtoType *NewProto 680 = New->getType()->getAsFunctionProtoType(); 681 682 // Determine whether this is the GNU C extension. 683 bool GNUCompatible = 684 Context.typesAreCompatible(OldProto->getResultType(), 685 NewProto->getResultType()) && 686 (OldProto->isVariadic() == NewProto->isVariadic()); 687 for (unsigned Idx = 0, End = Old->getNumParams(); 688 GNUCompatible && Idx != End; ++Idx) { 689 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 690 ParmVarDecl *NewParm = New->getParamDecl(Idx); 691 if (Context.typesAreCompatible(OldParm->getType(), 692 NewProto->getArgType(Idx))) { 693 ArgTypes.push_back(NewParm->getType()); 694 } else if (Context.typesAreCompatible(OldParm->getType(), 695 NewParm->getType())) { 696 GNUCompatibleParamWarning Warn 697 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 698 Warnings.push_back(Warn); 699 ArgTypes.push_back(NewParm->getType()); 700 } else 701 GNUCompatible = false; 702 } 703 704 if (GNUCompatible) { 705 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 706 Diag(Warnings[Warn].NewParm->getLocation(), 707 diag::ext_param_promoted_not_compatible_with_prototype) 708 << Warnings[Warn].PromotedType 709 << Warnings[Warn].OldParm->getType(); 710 Diag(Warnings[Warn].OldParm->getLocation(), 711 diag::note_previous_declaration); 712 } 713 714 New->setType(Context.getFunctionType(NewProto->getResultType(), 715 &ArgTypes[0], ArgTypes.size(), 716 NewProto->isVariadic(), 717 NewProto->getTypeQuals())); 718 return MergeCompatibleFunctionDecls(New, Old); 719 } 720 721 // Fall through to diagnose conflicting types. 722 } 723 724 // A function that has already been declared has been redeclared or defined 725 // with a different type- show appropriate diagnostic 726 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 727 // The user has declared a builtin function with an incompatible 728 // signature. 729 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 730 // The function the user is redeclaring is a library-defined 731 // function like 'malloc' or 'printf'. Warn about the 732 // redeclaration, then ignore it. 733 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 734 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 735 << Old << Old->getType(); 736 return true; 737 } 738 739 PrevDiag = diag::note_previous_builtin_declaration; 740 } 741 742 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 743 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 744 return true; 745} 746 747/// \brief Completes the merge of two function declarations that are 748/// known to be compatible. 749/// 750/// This routine handles the merging of attributes and other 751/// properties of function declarations form the old declaration to 752/// the new declaration, once we know that New is in fact a 753/// redeclaration of Old. 754/// 755/// \returns false 756bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 757 // Merge the attributes 758 MergeAttributes(New, Old, Context); 759 760 // Merge the storage class. 761 New->setStorageClass(Old->getStorageClass()); 762 763 // FIXME: need to implement inline semantics 764 765 // Merge "pure" flag. 766 if (Old->isPure()) 767 New->setPure(); 768 769 // Merge the "deleted" flag. 770 if (Old->isDeleted()) 771 New->setDeleted(); 772 773 if (getLangOptions().CPlusPlus) 774 return MergeCXXFunctionDecl(New, Old); 775 776 return false; 777} 778 779/// Predicate for C "tentative" external object definitions (C99 6.9.2). 780static bool isTentativeDefinition(VarDecl *VD) { 781 if (VD->isFileVarDecl()) 782 return (!VD->getInit() && 783 (VD->getStorageClass() == VarDecl::None || 784 VD->getStorageClass() == VarDecl::Static)); 785 return false; 786} 787 788/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 789/// when dealing with C "tentative" external object definitions (C99 6.9.2). 790void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 791 bool VDIsTentative = isTentativeDefinition(VD); 792 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 793 794 // FIXME: I don't think this will actually see all of the 795 // redefinitions. Can't we check this property on-the-fly? 796 for (IdentifierResolver::iterator I = IdResolver.begin(VD->getIdentifier()), 797 E = IdResolver.end(); 798 I != E; ++I) { 799 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 800 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 801 802 // Handle the following case: 803 // int a[10]; 804 // int a[]; - the code below makes sure we set the correct type. 805 // int a[11]; - this is an error, size isn't 10. 806 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 807 OldDecl->getType()->isConstantArrayType()) 808 VD->setType(OldDecl->getType()); 809 810 // Check for "tentative" definitions. We can't accomplish this in 811 // MergeVarDecl since the initializer hasn't been attached. 812 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 813 continue; 814 815 // Handle __private_extern__ just like extern. 816 if (OldDecl->getStorageClass() != VarDecl::Extern && 817 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 818 VD->getStorageClass() != VarDecl::Extern && 819 VD->getStorageClass() != VarDecl::PrivateExtern) { 820 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 821 Diag(OldDecl->getLocation(), diag::note_previous_definition); 822 // One redefinition error is enough. 823 break; 824 } 825 } 826 } 827} 828 829/// MergeVarDecl - We just parsed a variable 'New' which has the same name 830/// and scope as a previous declaration 'Old'. Figure out how to resolve this 831/// situation, merging decls or emitting diagnostics as appropriate. 832/// 833/// Tentative definition rules (C99 6.9.2p2) are checked by 834/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 835/// definitions here, since the initializer hasn't been attached. 836/// 837bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 838 // Verify the old decl was also a variable. 839 VarDecl *Old = dyn_cast<VarDecl>(OldD); 840 if (!Old) { 841 Diag(New->getLocation(), diag::err_redefinition_different_kind) 842 << New->getDeclName(); 843 Diag(OldD->getLocation(), diag::note_previous_definition); 844 return true; 845 } 846 847 MergeAttributes(New, Old, Context); 848 849 // Merge the types 850 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 851 if (MergedT.isNull()) { 852 Diag(New->getLocation(), diag::err_redefinition_different_type) 853 << New->getDeclName(); 854 Diag(Old->getLocation(), diag::note_previous_definition); 855 return true; 856 } 857 New->setType(MergedT); 858 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 859 if (New->getStorageClass() == VarDecl::Static && 860 (Old->getStorageClass() == VarDecl::None || 861 Old->getStorageClass() == VarDecl::Extern)) { 862 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 863 Diag(Old->getLocation(), diag::note_previous_definition); 864 return true; 865 } 866 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 867 if (New->getStorageClass() != VarDecl::Static && 868 Old->getStorageClass() == VarDecl::Static) { 869 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 870 Diag(Old->getLocation(), diag::note_previous_definition); 871 return true; 872 } 873 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 874 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 875 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 876 Diag(Old->getLocation(), diag::note_previous_definition); 877 return true; 878 } 879 return false; 880} 881 882/// CheckParmsForFunctionDef - Check that the parameters of the given 883/// function are appropriate for the definition of a function. This 884/// takes care of any checks that cannot be performed on the 885/// declaration itself, e.g., that the types of each of the function 886/// parameters are complete. 887bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 888 bool HasInvalidParm = false; 889 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 890 ParmVarDecl *Param = FD->getParamDecl(p); 891 892 // C99 6.7.5.3p4: the parameters in a parameter type list in a 893 // function declarator that is part of a function definition of 894 // that function shall not have incomplete type. 895 if (!Param->isInvalidDecl() && 896 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 897 diag::err_typecheck_decl_incomplete_type)) { 898 Param->setInvalidDecl(); 899 HasInvalidParm = true; 900 } 901 902 // C99 6.9.1p5: If the declarator includes a parameter type list, the 903 // declaration of each parameter shall include an identifier. 904 if (Param->getIdentifier() == 0 && 905 !Param->isImplicit() && 906 !getLangOptions().CPlusPlus) 907 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 908 } 909 910 return HasInvalidParm; 911} 912 913/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 914/// no declarator (e.g. "struct foo;") is parsed. 915Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 916 TagDecl *Tag = 0; 917 if (DS.getTypeSpecType() == DeclSpec::TST_class || 918 DS.getTypeSpecType() == DeclSpec::TST_struct || 919 DS.getTypeSpecType() == DeclSpec::TST_union || 920 DS.getTypeSpecType() == DeclSpec::TST_enum) 921 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 922 923 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 924 if (!Record->getDeclName() && Record->isDefinition() && 925 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 926 return BuildAnonymousStructOrUnion(S, DS, Record); 927 928 // Microsoft allows unnamed struct/union fields. Don't complain 929 // about them. 930 // FIXME: Should we support Microsoft's extensions in this area? 931 if (Record->getDeclName() && getLangOptions().Microsoft) 932 return Tag; 933 } 934 935 if (!DS.isMissingDeclaratorOk() && 936 DS.getTypeSpecType() != DeclSpec::TST_error) { 937 // Warn about typedefs of enums without names, since this is an 938 // extension in both Microsoft an GNU. 939 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 940 Tag && isa<EnumDecl>(Tag)) { 941 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 942 << DS.getSourceRange(); 943 return Tag; 944 } 945 946 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 947 << DS.getSourceRange(); 948 return 0; 949 } 950 951 return Tag; 952} 953 954/// InjectAnonymousStructOrUnionMembers - Inject the members of the 955/// anonymous struct or union AnonRecord into the owning context Owner 956/// and scope S. This routine will be invoked just after we realize 957/// that an unnamed union or struct is actually an anonymous union or 958/// struct, e.g., 959/// 960/// @code 961/// union { 962/// int i; 963/// float f; 964/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 965/// // f into the surrounding scope.x 966/// @endcode 967/// 968/// This routine is recursive, injecting the names of nested anonymous 969/// structs/unions into the owning context and scope as well. 970bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 971 RecordDecl *AnonRecord) { 972 bool Invalid = false; 973 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 974 FEnd = AnonRecord->field_end(); 975 F != FEnd; ++F) { 976 if ((*F)->getDeclName()) { 977 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 978 LookupOrdinaryName, true); 979 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 980 // C++ [class.union]p2: 981 // The names of the members of an anonymous union shall be 982 // distinct from the names of any other entity in the 983 // scope in which the anonymous union is declared. 984 unsigned diagKind 985 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 986 : diag::err_anonymous_struct_member_redecl; 987 Diag((*F)->getLocation(), diagKind) 988 << (*F)->getDeclName(); 989 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 990 Invalid = true; 991 } else { 992 // C++ [class.union]p2: 993 // For the purpose of name lookup, after the anonymous union 994 // definition, the members of the anonymous union are 995 // considered to have been defined in the scope in which the 996 // anonymous union is declared. 997 Owner->makeDeclVisibleInContext(*F); 998 S->AddDecl(*F); 999 IdResolver.AddDecl(*F); 1000 } 1001 } else if (const RecordType *InnerRecordType 1002 = (*F)->getType()->getAsRecordType()) { 1003 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1004 if (InnerRecord->isAnonymousStructOrUnion()) 1005 Invalid = Invalid || 1006 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1007 } 1008 } 1009 1010 return Invalid; 1011} 1012 1013/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1014/// anonymous structure or union. Anonymous unions are a C++ feature 1015/// (C++ [class.union]) and a GNU C extension; anonymous structures 1016/// are a GNU C and GNU C++ extension. 1017Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1018 RecordDecl *Record) { 1019 DeclContext *Owner = Record->getDeclContext(); 1020 1021 // Diagnose whether this anonymous struct/union is an extension. 1022 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1023 Diag(Record->getLocation(), diag::ext_anonymous_union); 1024 else if (!Record->isUnion()) 1025 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1026 1027 // C and C++ require different kinds of checks for anonymous 1028 // structs/unions. 1029 bool Invalid = false; 1030 if (getLangOptions().CPlusPlus) { 1031 const char* PrevSpec = 0; 1032 // C++ [class.union]p3: 1033 // Anonymous unions declared in a named namespace or in the 1034 // global namespace shall be declared static. 1035 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1036 (isa<TranslationUnitDecl>(Owner) || 1037 (isa<NamespaceDecl>(Owner) && 1038 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1039 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1040 Invalid = true; 1041 1042 // Recover by adding 'static'. 1043 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1044 } 1045 // C++ [class.union]p3: 1046 // A storage class is not allowed in a declaration of an 1047 // anonymous union in a class scope. 1048 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1049 isa<RecordDecl>(Owner)) { 1050 Diag(DS.getStorageClassSpecLoc(), 1051 diag::err_anonymous_union_with_storage_spec); 1052 Invalid = true; 1053 1054 // Recover by removing the storage specifier. 1055 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1056 PrevSpec); 1057 } 1058 1059 // C++ [class.union]p2: 1060 // The member-specification of an anonymous union shall only 1061 // define non-static data members. [Note: nested types and 1062 // functions cannot be declared within an anonymous union. ] 1063 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1064 MemEnd = Record->decls_end(); 1065 Mem != MemEnd; ++Mem) { 1066 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1067 // C++ [class.union]p3: 1068 // An anonymous union shall not have private or protected 1069 // members (clause 11). 1070 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1071 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1072 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1073 Invalid = true; 1074 } 1075 } else if ((*Mem)->isImplicit()) { 1076 // Any implicit members are fine. 1077 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1078 // This is a type that showed up in an 1079 // elaborated-type-specifier inside the anonymous struct or 1080 // union, but which actually declares a type outside of the 1081 // anonymous struct or union. It's okay. 1082 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1083 if (!MemRecord->isAnonymousStructOrUnion() && 1084 MemRecord->getDeclName()) { 1085 // This is a nested type declaration. 1086 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1087 << (int)Record->isUnion(); 1088 Invalid = true; 1089 } 1090 } else { 1091 // We have something that isn't a non-static data 1092 // member. Complain about it. 1093 unsigned DK = diag::err_anonymous_record_bad_member; 1094 if (isa<TypeDecl>(*Mem)) 1095 DK = diag::err_anonymous_record_with_type; 1096 else if (isa<FunctionDecl>(*Mem)) 1097 DK = diag::err_anonymous_record_with_function; 1098 else if (isa<VarDecl>(*Mem)) 1099 DK = diag::err_anonymous_record_with_static; 1100 Diag((*Mem)->getLocation(), DK) 1101 << (int)Record->isUnion(); 1102 Invalid = true; 1103 } 1104 } 1105 } else { 1106 // FIXME: Check GNU C semantics 1107 if (Record->isUnion() && !Owner->isRecord()) { 1108 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 1109 << (int)getLangOptions().CPlusPlus; 1110 Invalid = true; 1111 } 1112 } 1113 1114 if (!Record->isUnion() && !Owner->isRecord()) { 1115 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1116 << (int)getLangOptions().CPlusPlus; 1117 Invalid = true; 1118 } 1119 1120 // Create a declaration for this anonymous struct/union. 1121 NamedDecl *Anon = 0; 1122 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1123 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1124 /*IdentifierInfo=*/0, 1125 Context.getTypeDeclType(Record), 1126 /*BitWidth=*/0, /*Mutable=*/false); 1127 Anon->setAccess(AS_public); 1128 if (getLangOptions().CPlusPlus) 1129 FieldCollector->Add(cast<FieldDecl>(Anon)); 1130 } else { 1131 VarDecl::StorageClass SC; 1132 switch (DS.getStorageClassSpec()) { 1133 default: assert(0 && "Unknown storage class!"); 1134 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1135 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1136 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1137 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1138 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1139 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1140 case DeclSpec::SCS_mutable: 1141 // mutable can only appear on non-static class members, so it's always 1142 // an error here 1143 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1144 Invalid = true; 1145 SC = VarDecl::None; 1146 break; 1147 } 1148 1149 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1150 /*IdentifierInfo=*/0, 1151 Context.getTypeDeclType(Record), 1152 SC, DS.getSourceRange().getBegin()); 1153 } 1154 Anon->setImplicit(); 1155 1156 // Add the anonymous struct/union object to the current 1157 // context. We'll be referencing this object when we refer to one of 1158 // its members. 1159 Owner->addDecl(Anon); 1160 1161 // Inject the members of the anonymous struct/union into the owning 1162 // context and into the identifier resolver chain for name lookup 1163 // purposes. 1164 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1165 Invalid = true; 1166 1167 // Mark this as an anonymous struct/union type. Note that we do not 1168 // do this until after we have already checked and injected the 1169 // members of this anonymous struct/union type, because otherwise 1170 // the members could be injected twice: once by DeclContext when it 1171 // builds its lookup table, and once by 1172 // InjectAnonymousStructOrUnionMembers. 1173 Record->setAnonymousStructOrUnion(true); 1174 1175 if (Invalid) 1176 Anon->setInvalidDecl(); 1177 1178 return Anon; 1179} 1180 1181 1182/// GetNameForDeclarator - Determine the full declaration name for the 1183/// given Declarator. 1184DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1185 switch (D.getKind()) { 1186 case Declarator::DK_Abstract: 1187 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1188 return DeclarationName(); 1189 1190 case Declarator::DK_Normal: 1191 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1192 return DeclarationName(D.getIdentifier()); 1193 1194 case Declarator::DK_Constructor: { 1195 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1196 Ty = Context.getCanonicalType(Ty); 1197 return Context.DeclarationNames.getCXXConstructorName(Ty); 1198 } 1199 1200 case Declarator::DK_Destructor: { 1201 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1202 Ty = Context.getCanonicalType(Ty); 1203 return Context.DeclarationNames.getCXXDestructorName(Ty); 1204 } 1205 1206 case Declarator::DK_Conversion: { 1207 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1208 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1209 Ty = Context.getCanonicalType(Ty); 1210 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1211 } 1212 1213 case Declarator::DK_Operator: 1214 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1215 return Context.DeclarationNames.getCXXOperatorName( 1216 D.getOverloadedOperator()); 1217 } 1218 1219 assert(false && "Unknown name kind"); 1220 return DeclarationName(); 1221} 1222 1223/// isNearlyMatchingFunction - Determine whether the C++ functions 1224/// Declaration and Definition are "nearly" matching. This heuristic 1225/// is used to improve diagnostics in the case where an out-of-line 1226/// function definition doesn't match any declaration within 1227/// the class or namespace. 1228static bool isNearlyMatchingFunction(ASTContext &Context, 1229 FunctionDecl *Declaration, 1230 FunctionDecl *Definition) { 1231 if (Declaration->param_size() != Definition->param_size()) 1232 return false; 1233 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1234 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1235 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1236 1237 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1238 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1239 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1240 return false; 1241 } 1242 1243 return true; 1244} 1245 1246Sema::DeclTy * 1247Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1248 bool IsFunctionDefinition) { 1249 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1250 DeclarationName Name = GetNameForDeclarator(D); 1251 1252 // All of these full declarators require an identifier. If it doesn't have 1253 // one, the ParsedFreeStandingDeclSpec action should be used. 1254 if (!Name) { 1255 if (!D.getInvalidType()) // Reject this if we think it is valid. 1256 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1257 diag::err_declarator_need_ident) 1258 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1259 return 0; 1260 } 1261 1262 // The scope passed in may not be a decl scope. Zip up the scope tree until 1263 // we find one that is. 1264 while ((S->getFlags() & Scope::DeclScope) == 0 || 1265 (S->getFlags() & Scope::TemplateParamScope) != 0) 1266 S = S->getParent(); 1267 1268 DeclContext *DC; 1269 NamedDecl *PrevDecl; 1270 NamedDecl *New; 1271 bool InvalidDecl = false; 1272 1273 QualType R = GetTypeForDeclarator(D, S); 1274 if (R.isNull()) { 1275 InvalidDecl = true; 1276 R = Context.IntTy; 1277 } 1278 1279 // See if this is a redefinition of a variable in the same scope. 1280 if (D.getCXXScopeSpec().isInvalid()) { 1281 DC = CurContext; 1282 PrevDecl = 0; 1283 InvalidDecl = true; 1284 } else if (!D.getCXXScopeSpec().isSet()) { 1285 LookupNameKind NameKind = LookupOrdinaryName; 1286 1287 // If the declaration we're planning to build will be a function 1288 // or object with linkage, then look for another declaration with 1289 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1290 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1291 /* Do nothing*/; 1292 else if (R->isFunctionType()) { 1293 if (CurContext->isFunctionOrMethod()) 1294 NameKind = LookupRedeclarationWithLinkage; 1295 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1296 NameKind = LookupRedeclarationWithLinkage; 1297 1298 DC = CurContext; 1299 PrevDecl = LookupName(S, Name, NameKind, true, 1300 D.getDeclSpec().getStorageClassSpec() != 1301 DeclSpec::SCS_static, 1302 D.getIdentifierLoc()); 1303 } else { // Something like "int foo::x;" 1304 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1305 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1306 1307 // C++ 7.3.1.2p2: 1308 // Members (including explicit specializations of templates) of a named 1309 // namespace can also be defined outside that namespace by explicit 1310 // qualification of the name being defined, provided that the entity being 1311 // defined was already declared in the namespace and the definition appears 1312 // after the point of declaration in a namespace that encloses the 1313 // declarations namespace. 1314 // 1315 // Note that we only check the context at this point. We don't yet 1316 // have enough information to make sure that PrevDecl is actually 1317 // the declaration we want to match. For example, given: 1318 // 1319 // class X { 1320 // void f(); 1321 // void f(float); 1322 // }; 1323 // 1324 // void X::f(int) { } // ill-formed 1325 // 1326 // In this case, PrevDecl will point to the overload set 1327 // containing the two f's declared in X, but neither of them 1328 // matches. 1329 1330 // First check whether we named the global scope. 1331 if (isa<TranslationUnitDecl>(DC)) { 1332 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1333 << Name << D.getCXXScopeSpec().getRange(); 1334 } else if (!CurContext->Encloses(DC)) { 1335 // The qualifying scope doesn't enclose the original declaration. 1336 // Emit diagnostic based on current scope. 1337 SourceLocation L = D.getIdentifierLoc(); 1338 SourceRange R = D.getCXXScopeSpec().getRange(); 1339 if (isa<FunctionDecl>(CurContext)) 1340 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1341 else 1342 Diag(L, diag::err_invalid_declarator_scope) 1343 << Name << cast<NamedDecl>(DC) << R; 1344 InvalidDecl = true; 1345 } 1346 } 1347 1348 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1349 // Maybe we will complain about the shadowed template parameter. 1350 InvalidDecl = InvalidDecl 1351 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1352 // Just pretend that we didn't see the previous declaration. 1353 PrevDecl = 0; 1354 } 1355 1356 // In C++, the previous declaration we find might be a tag type 1357 // (class or enum). In this case, the new declaration will hide the 1358 // tag type. Note that this does does not apply if we're declaring a 1359 // typedef (C++ [dcl.typedef]p4). 1360 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1361 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1362 PrevDecl = 0; 1363 1364 bool Redeclaration = false; 1365 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1366 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1367 InvalidDecl, Redeclaration); 1368 } else if (R->isFunctionType()) { 1369 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1370 IsFunctionDefinition, InvalidDecl, 1371 Redeclaration); 1372 } else { 1373 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1374 InvalidDecl, Redeclaration); 1375 } 1376 1377 if (New == 0) 1378 return 0; 1379 1380 // Set the lexical context. If the declarator has a C++ scope specifier, the 1381 // lexical context will be different from the semantic context. 1382 New->setLexicalDeclContext(CurContext); 1383 1384 // If this has an identifier and is not an invalid redeclaration, 1385 // add it to the scope stack. 1386 if (Name && !(Redeclaration && InvalidDecl)) 1387 PushOnScopeChains(New, S); 1388 // If any semantic error occurred, mark the decl as invalid. 1389 if (D.getInvalidType() || InvalidDecl) 1390 New->setInvalidDecl(); 1391 1392 return New; 1393} 1394 1395/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1396/// types into constant array types in certain situations which would otherwise 1397/// be errors (for GCC compatibility). 1398static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1399 ASTContext &Context, 1400 bool &SizeIsNegative) { 1401 // This method tries to turn a variable array into a constant 1402 // array even when the size isn't an ICE. This is necessary 1403 // for compatibility with code that depends on gcc's buggy 1404 // constant expression folding, like struct {char x[(int)(char*)2];} 1405 SizeIsNegative = false; 1406 1407 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1408 QualType Pointee = PTy->getPointeeType(); 1409 QualType FixedType = 1410 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1411 if (FixedType.isNull()) return FixedType; 1412 FixedType = Context.getPointerType(FixedType); 1413 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1414 return FixedType; 1415 } 1416 1417 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1418 if (!VLATy) 1419 return QualType(); 1420 // FIXME: We should probably handle this case 1421 if (VLATy->getElementType()->isVariablyModifiedType()) 1422 return QualType(); 1423 1424 Expr::EvalResult EvalResult; 1425 if (!VLATy->getSizeExpr() || 1426 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1427 !EvalResult.Val.isInt()) 1428 return QualType(); 1429 1430 llvm::APSInt &Res = EvalResult.Val.getInt(); 1431 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1432 return Context.getConstantArrayType(VLATy->getElementType(), 1433 Res, ArrayType::Normal, 0); 1434 1435 SizeIsNegative = true; 1436 return QualType(); 1437} 1438 1439/// \brief Register the given locally-scoped external C declaration so 1440/// that it can be found later for redeclarations 1441void 1442Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1443 Scope *S) { 1444 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1445 "Decl is not a locally-scoped decl!"); 1446 // Note that we have a locally-scoped external with this name. 1447 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1448 1449 if (!PrevDecl) 1450 return; 1451 1452 // If there was a previous declaration of this variable, it may be 1453 // in our identifier chain. Update the identifier chain with the new 1454 // declaration. 1455 if (IdResolver.ReplaceDecl(PrevDecl, ND)) { 1456 // The previous declaration was found on the identifer resolver 1457 // chain, so remove it from its scope. 1458 while (S && !S->isDeclScope(PrevDecl)) 1459 S = S->getParent(); 1460 1461 if (S) 1462 S->RemoveDecl(PrevDecl); 1463 } 1464} 1465 1466NamedDecl* 1467Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1468 QualType R, Decl* LastDeclarator, 1469 Decl* PrevDecl, bool& InvalidDecl, 1470 bool &Redeclaration) { 1471 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1472 if (D.getCXXScopeSpec().isSet()) { 1473 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1474 << D.getCXXScopeSpec().getRange(); 1475 InvalidDecl = true; 1476 // Pretend we didn't see the scope specifier. 1477 DC = 0; 1478 } 1479 1480 // Check that there are no default arguments (C++ only). 1481 if (getLangOptions().CPlusPlus) 1482 CheckExtraCXXDefaultArguments(D); 1483 1484 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1485 if (!NewTD) return 0; 1486 1487 // Handle attributes prior to checking for duplicates in MergeVarDecl 1488 ProcessDeclAttributes(NewTD, D); 1489 // Merge the decl with the existing one if appropriate. If the decl is 1490 // in an outer scope, it isn't the same thing. 1491 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1492 Redeclaration = true; 1493 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1494 InvalidDecl = true; 1495 } 1496 1497 if (S->getFnParent() == 0) { 1498 QualType T = NewTD->getUnderlyingType(); 1499 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1500 // then it shall have block scope. 1501 if (T->isVariablyModifiedType()) { 1502 bool SizeIsNegative; 1503 QualType FixedTy = 1504 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1505 if (!FixedTy.isNull()) { 1506 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1507 NewTD->setUnderlyingType(FixedTy); 1508 } else { 1509 if (SizeIsNegative) 1510 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1511 else if (T->isVariableArrayType()) 1512 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1513 else 1514 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1515 InvalidDecl = true; 1516 } 1517 } 1518 } 1519 return NewTD; 1520} 1521 1522/// \brief Determines whether the given declaration is an out-of-scope 1523/// previous declaration. 1524/// 1525/// This routine should be invoked when name lookup has found a 1526/// previous declaration (PrevDecl) that is not in the scope where a 1527/// new declaration by the same name is being introduced. If the new 1528/// declaration occurs in a local scope, previous declarations with 1529/// linkage may still be considered previous declarations (C99 1530/// 6.2.2p4-5, C++ [basic.link]p6). 1531/// 1532/// \param PrevDecl the previous declaration found by name 1533/// lookup 1534/// 1535/// \param DC the context in which the new declaration is being 1536/// declared. 1537/// 1538/// \returns true if PrevDecl is an out-of-scope previous declaration 1539/// for a new delcaration with the same name. 1540static bool 1541isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1542 ASTContext &Context) { 1543 if (!PrevDecl) 1544 return 0; 1545 1546 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1547 // case we need to check each of the overloaded functions. 1548 if (!PrevDecl->hasLinkage()) 1549 return false; 1550 1551 if (Context.getLangOptions().CPlusPlus) { 1552 // C++ [basic.link]p6: 1553 // If there is a visible declaration of an entity with linkage 1554 // having the same name and type, ignoring entities declared 1555 // outside the innermost enclosing namespace scope, the block 1556 // scope declaration declares that same entity and receives the 1557 // linkage of the previous declaration. 1558 DeclContext *OuterContext = DC->getLookupContext(); 1559 if (!OuterContext->isFunctionOrMethod()) 1560 // This rule only applies to block-scope declarations. 1561 return false; 1562 else { 1563 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1564 if (PrevOuterContext->isRecord()) 1565 // We found a member function: ignore it. 1566 return false; 1567 else { 1568 // Find the innermost enclosing namespace for the new and 1569 // previous declarations. 1570 while (!OuterContext->isFileContext()) 1571 OuterContext = OuterContext->getParent(); 1572 while (!PrevOuterContext->isFileContext()) 1573 PrevOuterContext = PrevOuterContext->getParent(); 1574 1575 // The previous declaration is in a different namespace, so it 1576 // isn't the same function. 1577 if (OuterContext->getPrimaryContext() != 1578 PrevOuterContext->getPrimaryContext()) 1579 return false; 1580 } 1581 } 1582 } 1583 1584 return true; 1585} 1586 1587NamedDecl* 1588Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1589 QualType R, Decl* LastDeclarator, 1590 NamedDecl* PrevDecl, bool& InvalidDecl, 1591 bool &Redeclaration) { 1592 DeclarationName Name = GetNameForDeclarator(D); 1593 1594 // Check that there are no default arguments (C++ only). 1595 if (getLangOptions().CPlusPlus) 1596 CheckExtraCXXDefaultArguments(D); 1597 1598 if (R.getTypePtr()->isObjCInterfaceType()) { 1599 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object); 1600 InvalidDecl = true; 1601 } 1602 1603 VarDecl *NewVD; 1604 VarDecl::StorageClass SC; 1605 switch (D.getDeclSpec().getStorageClassSpec()) { 1606 default: assert(0 && "Unknown storage class!"); 1607 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1608 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1609 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1610 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1611 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1612 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1613 case DeclSpec::SCS_mutable: 1614 // mutable can only appear on non-static class members, so it's always 1615 // an error here 1616 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1617 InvalidDecl = true; 1618 SC = VarDecl::None; 1619 break; 1620 } 1621 1622 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1623 if (!II) { 1624 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1625 << Name.getAsString(); 1626 return 0; 1627 } 1628 1629 if (DC->isRecord()) { 1630 // This is a static data member for a C++ class. 1631 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1632 D.getIdentifierLoc(), II, 1633 R); 1634 } else { 1635 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1636 if (S->getFnParent() == 0) { 1637 // C99 6.9p2: The storage-class specifiers auto and register shall not 1638 // appear in the declaration specifiers in an external declaration. 1639 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1640 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1641 InvalidDecl = true; 1642 } 1643 } 1644 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1645 II, R, SC, 1646 // FIXME: Move to DeclGroup... 1647 D.getDeclSpec().getSourceRange().getBegin()); 1648 NewVD->setThreadSpecified(ThreadSpecified); 1649 } 1650 NewVD->setNextDeclarator(LastDeclarator); 1651 1652 // Handle attributes prior to checking for duplicates in MergeVarDecl 1653 ProcessDeclAttributes(NewVD, D); 1654 1655 // Handle GNU asm-label extension (encoded as an attribute). 1656 if (Expr *E = (Expr*) D.getAsmLabel()) { 1657 // The parser guarantees this is a string. 1658 StringLiteral *SE = cast<StringLiteral>(E); 1659 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1660 SE->getByteLength()))); 1661 } 1662 1663 // Emit an error if an address space was applied to decl with local storage. 1664 // This includes arrays of objects with address space qualifiers, but not 1665 // automatic variables that point to other address spaces. 1666 // ISO/IEC TR 18037 S5.1.2 1667 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1668 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1669 InvalidDecl = true; 1670 } 1671 1672 if (NewVD->hasLocalStorage() && NewVD->getType().isObjCGCWeak()) { 1673 Diag(D.getIdentifierLoc(), diag::warn_attribute_weak_on_local); 1674 } 1675 1676 bool isIllegalVLA = R->isVariableArrayType() && NewVD->hasGlobalStorage(); 1677 bool isIllegalVM = R->isVariablyModifiedType() && NewVD->hasLinkage(); 1678 if (isIllegalVLA || isIllegalVM) { 1679 bool SizeIsNegative; 1680 QualType FixedTy = 1681 TryToFixInvalidVariablyModifiedType(R, Context, SizeIsNegative); 1682 if (!FixedTy.isNull()) { 1683 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1684 NewVD->setType(FixedTy); 1685 } else if (R->isVariableArrayType()) { 1686 NewVD->setInvalidDecl(); 1687 1688 const VariableArrayType *VAT = Context.getAsVariableArrayType(R); 1689 // FIXME: This won't give the correct result for 1690 // int a[10][n]; 1691 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1692 1693 if (NewVD->isFileVarDecl()) 1694 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1695 << SizeRange; 1696 else if (NewVD->getStorageClass() == VarDecl::Static) 1697 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1698 << SizeRange; 1699 else 1700 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1701 << SizeRange; 1702 } else { 1703 InvalidDecl = true; 1704 1705 if (NewVD->isFileVarDecl()) 1706 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1707 else 1708 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1709 } 1710 } 1711 1712 // If name lookup finds a previous declaration that is not in the 1713 // same scope as the new declaration, this may still be an 1714 // acceptable redeclaration. 1715 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1716 !(NewVD->hasLinkage() && 1717 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1718 PrevDecl = 0; 1719 1720 if (!PrevDecl && NewVD->isExternC(Context)) { 1721 // Since we did not find anything by this name and we're declaring 1722 // an extern "C" variable, look for a non-visible extern "C" 1723 // declaration with the same name. 1724 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1725 = LocallyScopedExternalDecls.find(Name); 1726 if (Pos != LocallyScopedExternalDecls.end()) 1727 PrevDecl = Pos->second; 1728 } 1729 1730 // Merge the decl with the existing one if appropriate. 1731 if (PrevDecl) { 1732 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1733 // The user tried to define a non-static data member 1734 // out-of-line (C++ [dcl.meaning]p1). 1735 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1736 << D.getCXXScopeSpec().getRange(); 1737 NewVD->Destroy(Context); 1738 return 0; 1739 } 1740 1741 Redeclaration = true; 1742 if (MergeVarDecl(NewVD, PrevDecl)) 1743 InvalidDecl = true; 1744 1745 if (D.getCXXScopeSpec().isSet()) { 1746 // No previous declaration in the qualifying scope. 1747 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1748 << Name << D.getCXXScopeSpec().getRange(); 1749 InvalidDecl = true; 1750 } 1751 } 1752 1753 // If this is a locally-scoped extern C variable, update the map of 1754 // such variables. 1755 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1756 !InvalidDecl) 1757 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1758 1759 return NewVD; 1760} 1761 1762NamedDecl* 1763Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1764 QualType R, Decl *LastDeclarator, 1765 NamedDecl* PrevDecl, bool IsFunctionDefinition, 1766 bool& InvalidDecl, bool &Redeclaration) { 1767 assert(R.getTypePtr()->isFunctionType()); 1768 1769 DeclarationName Name = GetNameForDeclarator(D); 1770 FunctionDecl::StorageClass SC = FunctionDecl::None; 1771 switch (D.getDeclSpec().getStorageClassSpec()) { 1772 default: assert(0 && "Unknown storage class!"); 1773 case DeclSpec::SCS_auto: 1774 case DeclSpec::SCS_register: 1775 case DeclSpec::SCS_mutable: 1776 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1777 diag::err_typecheck_sclass_func); 1778 InvalidDecl = true; 1779 break; 1780 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1781 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1782 case DeclSpec::SCS_static: { 1783 if (DC->getLookupContext()->isFunctionOrMethod()) { 1784 // C99 6.7.1p5: 1785 // The declaration of an identifier for a function that has 1786 // block scope shall have no explicit storage-class specifier 1787 // other than extern 1788 // See also (C++ [dcl.stc]p4). 1789 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1790 diag::err_static_block_func); 1791 SC = FunctionDecl::None; 1792 } else 1793 SC = FunctionDecl::Static; 1794 break; 1795 } 1796 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1797 } 1798 1799 bool isInline = D.getDeclSpec().isInlineSpecified(); 1800 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1801 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1802 1803 FunctionDecl *NewFD; 1804 if (D.getKind() == Declarator::DK_Constructor) { 1805 // This is a C++ constructor declaration. 1806 assert(DC->isRecord() && 1807 "Constructors can only be declared in a member context"); 1808 1809 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1810 1811 // Create the new declaration 1812 NewFD = CXXConstructorDecl::Create(Context, 1813 cast<CXXRecordDecl>(DC), 1814 D.getIdentifierLoc(), Name, R, 1815 isExplicit, isInline, 1816 /*isImplicitlyDeclared=*/false); 1817 1818 if (InvalidDecl) 1819 NewFD->setInvalidDecl(); 1820 } else if (D.getKind() == Declarator::DK_Destructor) { 1821 // This is a C++ destructor declaration. 1822 if (DC->isRecord()) { 1823 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1824 1825 NewFD = CXXDestructorDecl::Create(Context, 1826 cast<CXXRecordDecl>(DC), 1827 D.getIdentifierLoc(), Name, R, 1828 isInline, 1829 /*isImplicitlyDeclared=*/false); 1830 1831 if (InvalidDecl) 1832 NewFD->setInvalidDecl(); 1833 } else { 1834 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1835 1836 // Create a FunctionDecl to satisfy the function definition parsing 1837 // code path. 1838 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1839 Name, R, SC, isInline, 1840 /*hasPrototype=*/true, 1841 // FIXME: Move to DeclGroup... 1842 D.getDeclSpec().getSourceRange().getBegin()); 1843 InvalidDecl = true; 1844 NewFD->setInvalidDecl(); 1845 } 1846 } else if (D.getKind() == Declarator::DK_Conversion) { 1847 if (!DC->isRecord()) { 1848 Diag(D.getIdentifierLoc(), 1849 diag::err_conv_function_not_member); 1850 return 0; 1851 } else { 1852 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1853 1854 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1855 D.getIdentifierLoc(), Name, R, 1856 isInline, isExplicit); 1857 1858 if (InvalidDecl) 1859 NewFD->setInvalidDecl(); 1860 } 1861 } else if (DC->isRecord()) { 1862 // This is a C++ method declaration. 1863 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1864 D.getIdentifierLoc(), Name, R, 1865 (SC == FunctionDecl::Static), isInline); 1866 } else { 1867 NewFD = FunctionDecl::Create(Context, DC, 1868 D.getIdentifierLoc(), 1869 Name, R, SC, isInline, 1870 /*hasPrototype=*/ 1871 (getLangOptions().CPlusPlus || 1872 (D.getNumTypeObjects() && 1873 D.getTypeObject(0).Fun.hasPrototype)), 1874 // FIXME: Move to DeclGroup... 1875 D.getDeclSpec().getSourceRange().getBegin()); 1876 } 1877 NewFD->setNextDeclarator(LastDeclarator); 1878 1879 // Set the lexical context. If the declarator has a C++ 1880 // scope specifier, the lexical context will be different 1881 // from the semantic context. 1882 NewFD->setLexicalDeclContext(CurContext); 1883 1884 // Handle GNU asm-label extension (encoded as an attribute). 1885 if (Expr *E = (Expr*) D.getAsmLabel()) { 1886 // The parser guarantees this is a string. 1887 StringLiteral *SE = cast<StringLiteral>(E); 1888 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1889 SE->getByteLength()))); 1890 } 1891 1892 // Copy the parameter declarations from the declarator D to 1893 // the function declaration NewFD, if they are available. 1894 if (D.getNumTypeObjects() > 0) { 1895 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1896 1897 // Create Decl objects for each parameter, adding them to the 1898 // FunctionDecl. 1899 llvm::SmallVector<ParmVarDecl*, 16> Params; 1900 1901 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1902 // function that takes no arguments, not a function that takes a 1903 // single void argument. 1904 // We let through "const void" here because Sema::GetTypeForDeclarator 1905 // already checks for that case. 1906 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1907 FTI.ArgInfo[0].Param && 1908 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1909 // empty arg list, don't push any params. 1910 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1911 1912 // In C++, the empty parameter-type-list must be spelled "void"; a 1913 // typedef of void is not permitted. 1914 if (getLangOptions().CPlusPlus && 1915 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1916 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1917 } 1918 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1919 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1920 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1921 } 1922 1923 NewFD->setParams(Context, &Params[0], Params.size()); 1924 } else if (R->getAsTypedefType()) { 1925 // When we're declaring a function with a typedef, as in the 1926 // following example, we'll need to synthesize (unnamed) 1927 // parameters for use in the declaration. 1928 // 1929 // @code 1930 // typedef void fn(int); 1931 // fn f; 1932 // @endcode 1933 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 1934 if (!FT) { 1935 // This is a typedef of a function with no prototype, so we 1936 // don't need to do anything. 1937 } else if ((FT->getNumArgs() == 0) || 1938 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1939 FT->getArgType(0)->isVoidType())) { 1940 // This is a zero-argument function. We don't need to do anything. 1941 } else { 1942 // Synthesize a parameter for each argument type. 1943 llvm::SmallVector<ParmVarDecl*, 16> Params; 1944 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 1945 ArgType != FT->arg_type_end(); ++ArgType) { 1946 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 1947 SourceLocation(), 0, 1948 *ArgType, VarDecl::None, 1949 0); 1950 Param->setImplicit(); 1951 Params.push_back(Param); 1952 } 1953 1954 NewFD->setParams(Context, &Params[0], Params.size()); 1955 } 1956 } 1957 1958 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1959 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1960 else if (isa<CXXDestructorDecl>(NewFD)) { 1961 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1962 Record->setUserDeclaredDestructor(true); 1963 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1964 // user-defined destructor. 1965 Record->setPOD(false); 1966 } else if (CXXConversionDecl *Conversion = 1967 dyn_cast<CXXConversionDecl>(NewFD)) 1968 ActOnConversionDeclarator(Conversion); 1969 1970 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1971 if (NewFD->isOverloadedOperator() && 1972 CheckOverloadedOperatorDeclaration(NewFD)) 1973 NewFD->setInvalidDecl(); 1974 1975 // If name lookup finds a previous declaration that is not in the 1976 // same scope as the new declaration, this may still be an 1977 // acceptable redeclaration. 1978 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1979 !(NewFD->hasLinkage() && 1980 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1981 PrevDecl = 0; 1982 1983 if (!PrevDecl && NewFD->isExternC(Context)) { 1984 // Since we did not find anything by this name and we're declaring 1985 // an extern "C" function, look for a non-visible extern "C" 1986 // declaration with the same name. 1987 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1988 = LocallyScopedExternalDecls.find(Name); 1989 if (Pos != LocallyScopedExternalDecls.end()) 1990 PrevDecl = Pos->second; 1991 } 1992 1993 // Merge or overload the declaration with an existing declaration of 1994 // the same name, if appropriate. 1995 bool OverloadableAttrRequired = false; 1996 if (PrevDecl) { 1997 // Determine whether NewFD is an overload of PrevDecl or 1998 // a declaration that requires merging. If it's an overload, 1999 // there's no more work to do here; we'll just add the new 2000 // function to the scope. 2001 OverloadedFunctionDecl::function_iterator MatchedDecl; 2002 2003 if (!getLangOptions().CPlusPlus && 2004 AllowOverloadingOfFunction(PrevDecl, Context)) { 2005 OverloadableAttrRequired = true; 2006 2007 // Functions marked "overloadable" must have a prototype (that 2008 // we can't get through declaration merging). 2009 if (!R->getAsFunctionProtoType()) { 2010 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2011 << NewFD; 2012 InvalidDecl = true; 2013 Redeclaration = true; 2014 2015 // Turn this into a variadic function with no parameters. 2016 R = Context.getFunctionType(R->getAsFunctionType()->getResultType(), 2017 0, 0, true, 0); 2018 NewFD->setType(R); 2019 } 2020 } 2021 2022 if (PrevDecl && 2023 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2024 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2025 Redeclaration = true; 2026 Decl *OldDecl = PrevDecl; 2027 2028 // If PrevDecl was an overloaded function, extract the 2029 // FunctionDecl that matched. 2030 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2031 OldDecl = *MatchedDecl; 2032 2033 // NewFD and PrevDecl represent declarations that need to be 2034 // merged. 2035 if (MergeFunctionDecl(NewFD, OldDecl)) 2036 InvalidDecl = true; 2037 2038 if (!InvalidDecl) { 2039 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2040 2041 // An out-of-line member function declaration must also be a 2042 // definition (C++ [dcl.meaning]p1). 2043 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 2044 !InvalidDecl) { 2045 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2046 << D.getCXXScopeSpec().getRange(); 2047 NewFD->setInvalidDecl(); 2048 } 2049 } 2050 } 2051 } 2052 2053 if (D.getCXXScopeSpec().isSet() && 2054 (!PrevDecl || !Redeclaration)) { 2055 // The user tried to provide an out-of-line definition for a 2056 // function that is a member of a class or namespace, but there 2057 // was no such member function declared (C++ [class.mfct]p2, 2058 // C++ [namespace.memdef]p2). For example: 2059 // 2060 // class X { 2061 // void f() const; 2062 // }; 2063 // 2064 // void X::f() { } // ill-formed 2065 // 2066 // Complain about this problem, and attempt to suggest close 2067 // matches (e.g., those that differ only in cv-qualifiers and 2068 // whether the parameter types are references). 2069 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2070 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2071 InvalidDecl = true; 2072 2073 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2074 true); 2075 assert(!Prev.isAmbiguous() && 2076 "Cannot have an ambiguity in previous-declaration lookup"); 2077 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2078 Func != FuncEnd; ++Func) { 2079 if (isa<FunctionDecl>(*Func) && 2080 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2081 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2082 } 2083 2084 PrevDecl = 0; 2085 } 2086 2087 // Handle attributes. We need to have merged decls when handling attributes 2088 // (for example to check for conflicts, etc). 2089 ProcessDeclAttributes(NewFD, D); 2090 AddKnownFunctionAttributes(NewFD); 2091 2092 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2093 // If a function name is overloadable in C, then every function 2094 // with that name must be marked "overloadable". 2095 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2096 << Redeclaration << NewFD; 2097 if (PrevDecl) 2098 Diag(PrevDecl->getLocation(), 2099 diag::note_attribute_overloadable_prev_overload); 2100 NewFD->addAttr(::new (Context) OverloadableAttr()); 2101 } 2102 2103 if (getLangOptions().CPlusPlus) { 2104 // In C++, check default arguments now that we have merged decls. Unless 2105 // the lexical context is the class, because in this case this is done 2106 // during delayed parsing anyway. 2107 if (!CurContext->isRecord()) 2108 CheckCXXDefaultArguments(NewFD); 2109 2110 // An out-of-line member function declaration must also be a 2111 // definition (C++ [dcl.meaning]p1). 2112 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2113 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2114 << D.getCXXScopeSpec().getRange(); 2115 InvalidDecl = true; 2116 } 2117 } 2118 2119 // If this is a locally-scoped extern C function, update the 2120 // map of such names. 2121 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2122 && !InvalidDecl) 2123 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2124 2125 return NewFD; 2126} 2127 2128bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2129 // FIXME: Need strict checking. In C89, we need to check for 2130 // any assignment, increment, decrement, function-calls, or 2131 // commas outside of a sizeof. In C99, it's the same list, 2132 // except that the aforementioned are allowed in unevaluated 2133 // expressions. Everything else falls under the 2134 // "may accept other forms of constant expressions" exception. 2135 // (We never end up here for C++, so the constant expression 2136 // rules there don't matter.) 2137 if (Init->isConstantInitializer(Context)) 2138 return false; 2139 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2140 << Init->getSourceRange(); 2141 return true; 2142} 2143 2144void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2145 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2146} 2147 2148/// AddInitializerToDecl - Adds the initializer Init to the 2149/// declaration dcl. If DirectInit is true, this is C++ direct 2150/// initialization rather than copy initialization. 2151void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2152 Decl *RealDecl = static_cast<Decl *>(dcl); 2153 // If there is no declaration, there was an error parsing it. Just ignore 2154 // the initializer. 2155 if (RealDecl == 0) 2156 return; 2157 2158 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2159 if (!VDecl) { 2160 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2161 RealDecl->setInvalidDecl(); 2162 return; 2163 } 2164 2165 // Take ownership of the expression, now that we're sure we have somewhere 2166 // to put it. 2167 Expr *Init = static_cast<Expr *>(init.release()); 2168 assert(Init && "missing initializer"); 2169 2170 // Get the decls type and save a reference for later, since 2171 // CheckInitializerTypes may change it. 2172 QualType DclT = VDecl->getType(), SavT = DclT; 2173 if (VDecl->isBlockVarDecl()) { 2174 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2175 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2176 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2177 VDecl->setInvalidDecl(); 2178 } else if (!VDecl->isInvalidDecl()) { 2179 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2180 VDecl->getDeclName(), DirectInit)) 2181 VDecl->setInvalidDecl(); 2182 2183 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2184 // Don't check invalid declarations to avoid emitting useless diagnostics. 2185 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2186 if (SC == VarDecl::Static) // C99 6.7.8p4. 2187 CheckForConstantInitializer(Init, DclT); 2188 } 2189 } 2190 } else if (VDecl->isFileVarDecl()) { 2191 if (VDecl->getStorageClass() == VarDecl::Extern) 2192 Diag(VDecl->getLocation(), diag::warn_extern_init); 2193 if (!VDecl->isInvalidDecl()) 2194 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2195 VDecl->getDeclName(), DirectInit)) 2196 VDecl->setInvalidDecl(); 2197 2198 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2199 // Don't check invalid declarations to avoid emitting useless diagnostics. 2200 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2201 // C99 6.7.8p4. All file scoped initializers need to be constant. 2202 CheckForConstantInitializer(Init, DclT); 2203 } 2204 } 2205 // If the type changed, it means we had an incomplete type that was 2206 // completed by the initializer. For example: 2207 // int ary[] = { 1, 3, 5 }; 2208 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2209 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2210 VDecl->setType(DclT); 2211 Init->setType(DclT); 2212 } 2213 2214 // Attach the initializer to the decl. 2215 VDecl->setInit(Init); 2216 return; 2217} 2218 2219void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2220 Decl *RealDecl = static_cast<Decl *>(dcl); 2221 2222 // If there is no declaration, there was an error parsing it. Just ignore it. 2223 if (RealDecl == 0) 2224 return; 2225 2226 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2227 QualType Type = Var->getType(); 2228 // C++ [dcl.init.ref]p3: 2229 // The initializer can be omitted for a reference only in a 2230 // parameter declaration (8.3.5), in the declaration of a 2231 // function return type, in the declaration of a class member 2232 // within its class declaration (9.2), and where the extern 2233 // specifier is explicitly used. 2234 if (Type->isReferenceType() && 2235 Var->getStorageClass() != VarDecl::Extern && 2236 Var->getStorageClass() != VarDecl::PrivateExtern) { 2237 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2238 << Var->getDeclName() 2239 << SourceRange(Var->getLocation(), Var->getLocation()); 2240 Var->setInvalidDecl(); 2241 return; 2242 } 2243 2244 // C++ [dcl.init]p9: 2245 // 2246 // If no initializer is specified for an object, and the object 2247 // is of (possibly cv-qualified) non-POD class type (or array 2248 // thereof), the object shall be default-initialized; if the 2249 // object is of const-qualified type, the underlying class type 2250 // shall have a user-declared default constructor. 2251 if (getLangOptions().CPlusPlus) { 2252 QualType InitType = Type; 2253 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2254 InitType = Array->getElementType(); 2255 if (Var->getStorageClass() != VarDecl::Extern && 2256 Var->getStorageClass() != VarDecl::PrivateExtern && 2257 InitType->isRecordType()) { 2258 const CXXConstructorDecl *Constructor = 0; 2259 if (!DiagnoseIncompleteType(Var->getLocation(), InitType, 2260 diag::err_invalid_incomplete_type_use)) 2261 Constructor 2262 = PerformInitializationByConstructor(InitType, 0, 0, 2263 Var->getLocation(), 2264 SourceRange(Var->getLocation(), 2265 Var->getLocation()), 2266 Var->getDeclName(), 2267 IK_Default); 2268 if (!Constructor) 2269 Var->setInvalidDecl(); 2270 } 2271 } 2272 2273#if 0 2274 // FIXME: Temporarily disabled because we are not properly parsing 2275 // linkage specifications on declarations, e.g., 2276 // 2277 // extern "C" const CGPoint CGPointerZero; 2278 // 2279 // C++ [dcl.init]p9: 2280 // 2281 // If no initializer is specified for an object, and the 2282 // object is of (possibly cv-qualified) non-POD class type (or 2283 // array thereof), the object shall be default-initialized; if 2284 // the object is of const-qualified type, the underlying class 2285 // type shall have a user-declared default 2286 // constructor. Otherwise, if no initializer is specified for 2287 // an object, the object and its subobjects, if any, have an 2288 // indeterminate initial value; if the object or any of its 2289 // subobjects are of const-qualified type, the program is 2290 // ill-formed. 2291 // 2292 // This isn't technically an error in C, so we don't diagnose it. 2293 // 2294 // FIXME: Actually perform the POD/user-defined default 2295 // constructor check. 2296 if (getLangOptions().CPlusPlus && 2297 Context.getCanonicalType(Type).isConstQualified() && 2298 Var->getStorageClass() != VarDecl::Extern) 2299 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2300 << Var->getName() 2301 << SourceRange(Var->getLocation(), Var->getLocation()); 2302#endif 2303 } 2304} 2305 2306/// The declarators are chained together backwards, reverse the list. 2307Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2308 // Often we have single declarators, handle them quickly. 2309 Decl *Group = static_cast<Decl*>(group); 2310 if (Group == 0) 2311 return 0; 2312 2313 Decl *NewGroup = 0; 2314 if (Group->getNextDeclarator() == 0) 2315 NewGroup = Group; 2316 else { // reverse the list. 2317 while (Group) { 2318 Decl *Next = Group->getNextDeclarator(); 2319 Group->setNextDeclarator(NewGroup); 2320 NewGroup = Group; 2321 Group = Next; 2322 } 2323 } 2324 // Perform semantic analysis that depends on having fully processed both 2325 // the declarator and initializer. 2326 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2327 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2328 if (!IDecl) 2329 continue; 2330 QualType T = IDecl->getType(); 2331 2332 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2333 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2334 if (IDecl->isBlockVarDecl() && 2335 IDecl->getStorageClass() != VarDecl::Extern) { 2336 if (!IDecl->isInvalidDecl() && 2337 DiagnoseIncompleteType(IDecl->getLocation(), T, 2338 diag::err_typecheck_decl_incomplete_type)) 2339 IDecl->setInvalidDecl(); 2340 } 2341 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2342 // object that has file scope without an initializer, and without a 2343 // storage-class specifier or with the storage-class specifier "static", 2344 // constitutes a tentative definition. Note: A tentative definition with 2345 // external linkage is valid (C99 6.2.2p5). 2346 if (isTentativeDefinition(IDecl)) { 2347 if (T->isIncompleteArrayType()) { 2348 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2349 // array to be completed. Don't issue a diagnostic. 2350 } else if (!IDecl->isInvalidDecl() && 2351 DiagnoseIncompleteType(IDecl->getLocation(), T, 2352 diag::err_typecheck_decl_incomplete_type)) 2353 // C99 6.9.2p3: If the declaration of an identifier for an object is 2354 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2355 // declared type shall not be an incomplete type. 2356 IDecl->setInvalidDecl(); 2357 } 2358 if (IDecl->isFileVarDecl()) 2359 CheckForFileScopedRedefinitions(S, IDecl); 2360 } 2361 return NewGroup; 2362} 2363 2364/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2365/// to introduce parameters into function prototype scope. 2366Sema::DeclTy * 2367Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2368 const DeclSpec &DS = D.getDeclSpec(); 2369 2370 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2371 VarDecl::StorageClass StorageClass = VarDecl::None; 2372 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2373 StorageClass = VarDecl::Register; 2374 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2375 Diag(DS.getStorageClassSpecLoc(), 2376 diag::err_invalid_storage_class_in_func_decl); 2377 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2378 } 2379 if (DS.isThreadSpecified()) { 2380 Diag(DS.getThreadSpecLoc(), 2381 diag::err_invalid_storage_class_in_func_decl); 2382 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2383 } 2384 2385 // Check that there are no default arguments inside the type of this 2386 // parameter (C++ only). 2387 if (getLangOptions().CPlusPlus) 2388 CheckExtraCXXDefaultArguments(D); 2389 2390 // In this context, we *do not* check D.getInvalidType(). If the declarator 2391 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2392 // though it will not reflect the user specified type. 2393 QualType parmDeclType = GetTypeForDeclarator(D, S); 2394 2395 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2396 2397 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2398 // Can this happen for params? We already checked that they don't conflict 2399 // among each other. Here they can only shadow globals, which is ok. 2400 IdentifierInfo *II = D.getIdentifier(); 2401 if (II) { 2402 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2403 if (PrevDecl->isTemplateParameter()) { 2404 // Maybe we will complain about the shadowed template parameter. 2405 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2406 // Just pretend that we didn't see the previous declaration. 2407 PrevDecl = 0; 2408 } else if (S->isDeclScope(PrevDecl)) { 2409 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2410 2411 // Recover by removing the name 2412 II = 0; 2413 D.SetIdentifier(0, D.getIdentifierLoc()); 2414 } 2415 } 2416 } 2417 2418 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2419 // Doing the promotion here has a win and a loss. The win is the type for 2420 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2421 // code generator). The loss is the orginal type isn't preserved. For example: 2422 // 2423 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2424 // int blockvardecl[5]; 2425 // sizeof(parmvardecl); // size == 4 2426 // sizeof(blockvardecl); // size == 20 2427 // } 2428 // 2429 // For expressions, all implicit conversions are captured using the 2430 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2431 // 2432 // FIXME: If a source translation tool needs to see the original type, then 2433 // we need to consider storing both types (in ParmVarDecl)... 2434 // 2435 if (parmDeclType->isArrayType()) { 2436 // int x[restrict 4] -> int *restrict 2437 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2438 } else if (parmDeclType->isFunctionType()) 2439 parmDeclType = Context.getPointerType(parmDeclType); 2440 2441 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2442 D.getIdentifierLoc(), II, 2443 parmDeclType, StorageClass, 2444 0); 2445 2446 if (D.getInvalidType()) 2447 New->setInvalidDecl(); 2448 2449 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2450 if (D.getCXXScopeSpec().isSet()) { 2451 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2452 << D.getCXXScopeSpec().getRange(); 2453 New->setInvalidDecl(); 2454 } 2455 // Parameter declarators cannot be interface types. All ObjC objects are 2456 // passed by reference. 2457 if (parmDeclType->isObjCInterfaceType()) { 2458 Diag(D.getIdentifierLoc(), diag::err_object_cannot_be_by_value) 2459 << "passed"; 2460 New->setInvalidDecl(); 2461 } 2462 2463 // Add the parameter declaration into this scope. 2464 S->AddDecl(New); 2465 if (II) 2466 IdResolver.AddDecl(New); 2467 2468 ProcessDeclAttributes(New, D); 2469 return New; 2470 2471} 2472 2473void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2474 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2475 "Not a function declarator!"); 2476 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2477 2478 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2479 // for a K&R function. 2480 if (!FTI.hasPrototype) { 2481 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2482 if (FTI.ArgInfo[i].Param == 0) { 2483 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2484 << FTI.ArgInfo[i].Ident; 2485 // Implicitly declare the argument as type 'int' for lack of a better 2486 // type. 2487 DeclSpec DS; 2488 const char* PrevSpec; // unused 2489 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2490 PrevSpec); 2491 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2492 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2493 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2494 } 2495 } 2496 } 2497} 2498 2499Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2500 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2501 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2502 "Not a function declarator!"); 2503 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2504 2505 if (FTI.hasPrototype) { 2506 // FIXME: Diagnose arguments without names in C. 2507 } 2508 2509 Scope *ParentScope = FnBodyScope->getParent(); 2510 2511 return ActOnStartOfFunctionDef(FnBodyScope, 2512 ActOnDeclarator(ParentScope, D, 0, 2513 /*IsFunctionDefinition=*/true)); 2514} 2515 2516Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2517 Decl *decl = static_cast<Decl*>(D); 2518 FunctionDecl *FD = cast<FunctionDecl>(decl); 2519 2520 ActiveScope = FnBodyScope; 2521 2522 // See if this is a redefinition. 2523 const FunctionDecl *Definition; 2524 if (FD->getBody(Definition)) { 2525 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2526 Diag(Definition->getLocation(), diag::note_previous_definition); 2527 } 2528 2529 // Builtin functions cannot be defined. 2530 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2531 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2532 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2533 FD->setInvalidDecl(); 2534 } 2535 } 2536 2537 // The return type of a function definition must be complete 2538 // (C99 6.9.1p3) 2539 if (FD->getResultType()->isIncompleteType() && 2540 !FD->getResultType()->isVoidType()) { 2541 Diag(FD->getLocation(), diag::err_func_def_incomplete_result) << FD; 2542 FD->setInvalidDecl(); 2543 } 2544 2545 PushDeclContext(FnBodyScope, FD); 2546 2547 // Check the validity of our function parameters 2548 CheckParmsForFunctionDef(FD); 2549 2550 // Introduce our parameters into the function scope 2551 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2552 ParmVarDecl *Param = FD->getParamDecl(p); 2553 Param->setOwningFunction(FD); 2554 2555 // If this has an identifier, add it to the scope stack. 2556 if (Param->getIdentifier()) 2557 PushOnScopeChains(Param, FnBodyScope); 2558 } 2559 2560 // Checking attributes of current function definition 2561 // dllimport attribute. 2562 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2563 // dllimport attribute cannot be applied to definition. 2564 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2565 Diag(FD->getLocation(), 2566 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2567 << "dllimport"; 2568 FD->setInvalidDecl(); 2569 return FD; 2570 } else { 2571 // If a symbol previously declared dllimport is later defined, the 2572 // attribute is ignored in subsequent references, and a warning is 2573 // emitted. 2574 Diag(FD->getLocation(), 2575 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2576 << FD->getNameAsCString() << "dllimport"; 2577 } 2578 } 2579 return FD; 2580} 2581 2582static bool StatementCreatesScope(Stmt* S) { 2583 bool result = false; 2584 if (DeclStmt* DS = dyn_cast<DeclStmt>(S)) { 2585 for (DeclStmt::decl_iterator i = DS->decl_begin(); 2586 i != DS->decl_end(); ++i) { 2587 if (VarDecl* D = dyn_cast<VarDecl>(*i)) { 2588 result |= D->getType()->isVariablyModifiedType(); 2589 result |= !!D->getAttr<CleanupAttr>(); 2590 } else if (TypedefDecl* D = dyn_cast<TypedefDecl>(*i)) { 2591 result |= D->getUnderlyingType()->isVariablyModifiedType(); 2592 } 2593 } 2594 } 2595 2596 return result; 2597} 2598 2599void Sema::RecursiveCalcLabelScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2600 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2601 std::vector<void*>& ScopeStack, 2602 Stmt* CurStmt, 2603 Stmt* ParentCompoundStmt) { 2604 for (Stmt::child_iterator i = CurStmt->child_begin(); 2605 i != CurStmt->child_end(); ++i) { 2606 if (!*i) continue; 2607 if (StatementCreatesScope(*i)) { 2608 ScopeStack.push_back(*i); 2609 PopScopeMap[*i] = ParentCompoundStmt; 2610 } else if (isa<LabelStmt>(CurStmt)) { 2611 LabelScopeMap[CurStmt] = ScopeStack.size() ? ScopeStack.back() : 0; 2612 } 2613 if (isa<DeclStmt>(*i)) continue; 2614 Stmt* CurCompound = isa<CompoundStmt>(*i) ? *i : ParentCompoundStmt; 2615 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, 2616 *i, CurCompound); 2617 } 2618 2619 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2620 ScopeStack.pop_back(); 2621 } 2622} 2623 2624void Sema::RecursiveCalcJumpScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2625 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2626 llvm::DenseMap<Stmt*, void*>& GotoScopeMap, 2627 std::vector<void*>& ScopeStack, 2628 Stmt* CurStmt) { 2629 for (Stmt::child_iterator i = CurStmt->child_begin(); 2630 i != CurStmt->child_end(); ++i) { 2631 if (!*i) continue; 2632 if (StatementCreatesScope(*i)) { 2633 ScopeStack.push_back(*i); 2634 } else if (GotoStmt* GS = dyn_cast<GotoStmt>(*i)) { 2635 void* LScope = LabelScopeMap[GS->getLabel()]; 2636 if (LScope) { 2637 bool foundScopeInStack = false; 2638 for (unsigned i = ScopeStack.size(); i > 0; --i) { 2639 if (LScope == ScopeStack[i-1]) { 2640 foundScopeInStack = true; 2641 break; 2642 } 2643 } 2644 if (!foundScopeInStack) { 2645 Diag(GS->getSourceRange().getBegin(), diag::err_goto_into_scope); 2646 } 2647 } 2648 } 2649 if (isa<DeclStmt>(*i)) continue; 2650 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, 2651 ScopeStack, *i); 2652 } 2653 2654 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2655 ScopeStack.pop_back(); 2656 } 2657} 2658 2659Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2660 Decl *dcl = static_cast<Decl *>(D); 2661 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2662 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2663 FD->setBody(Body); 2664 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2665 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2666 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2667 MD->setBody((Stmt*)Body); 2668 } else { 2669 Body->Destroy(Context); 2670 return 0; 2671 } 2672 PopDeclContext(); 2673 2674 // FIXME: Temporary hack to workaround nested C++ functions. For example: 2675 // class C2 { 2676 // void f() { 2677 // class LC1 { 2678 // int m() { return 1; } 2679 // }; 2680 // } 2681 // }; 2682 if (ActiveScope == 0) 2683 return D; 2684 2685 // Verify and clean out per-function state. 2686 2687 bool HaveLabels = !ActiveScope->LabelMap.empty(); 2688 // Check goto/label use. 2689 for (Scope::LabelMapTy::iterator I = ActiveScope->LabelMap.begin(), 2690 E = ActiveScope->LabelMap.end(); I != E; ++I) { 2691 // Verify that we have no forward references left. If so, there was a goto 2692 // or address of a label taken, but no definition of it. Label fwd 2693 // definitions are indicated with a null substmt. 2694 LabelStmt *L = static_cast<LabelStmt*>(I->second); 2695 if (L->getSubStmt() == 0) { 2696 // Emit error. 2697 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2698 2699 // At this point, we have gotos that use the bogus label. Stitch it into 2700 // the function body so that they aren't leaked and that the AST is well 2701 // formed. 2702 if (Body) { 2703#if 0 2704 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2705 // and the AST is malformed anyway. We should just blow away 'L'. 2706 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2707 cast<CompoundStmt>(Body)->push_back(L); 2708#else 2709 L->Destroy(Context); 2710#endif 2711 } else { 2712 // The whole function wasn't parsed correctly, just delete this. 2713 L->Destroy(Context); 2714 } 2715 } 2716 } 2717 // This reset is for both functions and methods. 2718 ActiveScope = 0; 2719 2720 if (!Body) return D; 2721 2722 if (HaveLabels) { 2723 llvm::DenseMap<Stmt*, void*> LabelScopeMap; 2724 llvm::DenseMap<void*, Stmt*> PopScopeMap; 2725 llvm::DenseMap<Stmt*, void*> GotoScopeMap; 2726 std::vector<void*> ScopeStack; 2727 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, Body, Body); 2728 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, ScopeStack, Body); 2729 } 2730 2731 return D; 2732} 2733 2734/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2735/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2736NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2737 IdentifierInfo &II, Scope *S) { 2738 // Before we produce a declaration for an implicitly defined 2739 // function, see whether there was a locally-scoped declaration of 2740 // this name as a function or variable. If so, use that 2741 // (non-visible) declaration, and complain about it. 2742 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2743 = LocallyScopedExternalDecls.find(&II); 2744 if (Pos != LocallyScopedExternalDecls.end()) { 2745 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 2746 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 2747 return Pos->second; 2748 } 2749 2750 // Extension in C99. Legal in C90, but warn about it. 2751 if (getLangOptions().C99) 2752 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2753 else 2754 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2755 2756 // FIXME: handle stuff like: 2757 // void foo() { extern float X(); } 2758 // void bar() { X(); } <-- implicit decl for X in another scope. 2759 2760 // Set a Declarator for the implicit definition: int foo(); 2761 const char *Dummy; 2762 DeclSpec DS; 2763 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2764 Error = Error; // Silence warning. 2765 assert(!Error && "Error setting up implicit decl!"); 2766 Declarator D(DS, Declarator::BlockContext); 2767 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 2768 0, 0, 0, Loc, D), 2769 SourceLocation()); 2770 D.SetIdentifier(&II, Loc); 2771 2772 // Insert this function into translation-unit scope. 2773 2774 DeclContext *PrevDC = CurContext; 2775 CurContext = Context.getTranslationUnitDecl(); 2776 2777 FunctionDecl *FD = 2778 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2779 FD->setImplicit(); 2780 2781 CurContext = PrevDC; 2782 2783 AddKnownFunctionAttributes(FD); 2784 2785 return FD; 2786} 2787 2788/// \brief Adds any function attributes that we know a priori based on 2789/// the declaration of this function. 2790/// 2791/// These attributes can apply both to implicitly-declared builtins 2792/// (like __builtin___printf_chk) or to library-declared functions 2793/// like NSLog or printf. 2794void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 2795 if (FD->isInvalidDecl()) 2796 return; 2797 2798 // If this is a built-in function, map its builtin attributes to 2799 // actual attributes. 2800 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2801 // Handle printf-formatting attributes. 2802 unsigned FormatIdx; 2803 bool HasVAListArg; 2804 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 2805 if (!FD->getAttr<FormatAttr>()) 2806 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 2807 FormatIdx + 2)); 2808 } 2809 2810 // Mark const if we don't care about errno and that is the only 2811 // thing preventing the function from being const. This allows 2812 // IRgen to use LLVM intrinsics for such functions. 2813 if (!getLangOptions().MathErrno && 2814 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 2815 if (!FD->getAttr<ConstAttr>()) 2816 FD->addAttr(::new (Context) ConstAttr()); 2817 } 2818 } 2819 2820 IdentifierInfo *Name = FD->getIdentifier(); 2821 if (!Name) 2822 return; 2823 if ((!getLangOptions().CPlusPlus && 2824 FD->getDeclContext()->isTranslationUnit()) || 2825 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 2826 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 2827 LinkageSpecDecl::lang_c)) { 2828 // Okay: this could be a libc/libm/Objective-C function we know 2829 // about. 2830 } else 2831 return; 2832 2833 unsigned KnownID; 2834 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 2835 if (KnownFunctionIDs[KnownID] == Name) 2836 break; 2837 2838 switch (KnownID) { 2839 case id_NSLog: 2840 case id_NSLogv: 2841 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 2842 // FIXME: We known better than our headers. 2843 const_cast<FormatAttr *>(Format)->setType("printf"); 2844 } else 2845 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 2846 break; 2847 2848 case id_asprintf: 2849 case id_vasprintf: 2850 if (!FD->getAttr<FormatAttr>()) 2851 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 2852 break; 2853 2854 default: 2855 // Unknown function or known function without any attributes to 2856 // add. Do nothing. 2857 break; 2858 } 2859} 2860 2861TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2862 Decl *LastDeclarator) { 2863 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2864 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2865 2866 // Scope manipulation handled by caller. 2867 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2868 D.getIdentifierLoc(), 2869 D.getIdentifier(), 2870 T); 2871 NewTD->setNextDeclarator(LastDeclarator); 2872 if (D.getInvalidType()) 2873 NewTD->setInvalidDecl(); 2874 return NewTD; 2875} 2876 2877/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2878/// former case, Name will be non-null. In the later case, Name will be null. 2879/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2880/// reference/declaration/definition of a tag. 2881Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2882 SourceLocation KWLoc, const CXXScopeSpec &SS, 2883 IdentifierInfo *Name, SourceLocation NameLoc, 2884 AttributeList *Attr) { 2885 // If this is not a definition, it must have a name. 2886 assert((Name != 0 || TK == TK_Definition) && 2887 "Nameless record must be a definition!"); 2888 2889 TagDecl::TagKind Kind; 2890 switch (TagSpec) { 2891 default: assert(0 && "Unknown tag type!"); 2892 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2893 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2894 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2895 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2896 } 2897 2898 DeclContext *SearchDC = CurContext; 2899 DeclContext *DC = CurContext; 2900 NamedDecl *PrevDecl = 0; 2901 2902 bool Invalid = false; 2903 2904 if (Name && SS.isNotEmpty()) { 2905 // We have a nested-name tag ('struct foo::bar'). 2906 2907 // Check for invalid 'foo::'. 2908 if (SS.isInvalid()) { 2909 Name = 0; 2910 goto CreateNewDecl; 2911 } 2912 2913 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2914 SearchDC = DC; 2915 // Look-up name inside 'foo::'. 2916 PrevDecl = dyn_cast_or_null<TagDecl>( 2917 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 2918 2919 // A tag 'foo::bar' must already exist. 2920 if (PrevDecl == 0) { 2921 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2922 Name = 0; 2923 goto CreateNewDecl; 2924 } 2925 } else if (Name) { 2926 // If this is a named struct, check to see if there was a previous forward 2927 // declaration or definition. 2928 // FIXME: We're looking into outer scopes here, even when we 2929 // shouldn't be. Doing so can result in ambiguities that we 2930 // shouldn't be diagnosing. 2931 LookupResult R = LookupName(S, Name, LookupTagName, 2932 /*RedeclarationOnly=*/(TK != TK_Reference)); 2933 if (R.isAmbiguous()) { 2934 DiagnoseAmbiguousLookup(R, Name, NameLoc); 2935 // FIXME: This is not best way to recover from case like: 2936 // 2937 // struct S s; 2938 // 2939 // causes needless err_ovl_no_viable_function_in_init latter. 2940 Name = 0; 2941 PrevDecl = 0; 2942 Invalid = true; 2943 } 2944 else 2945 PrevDecl = R; 2946 2947 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2948 // FIXME: This makes sure that we ignore the contexts associated 2949 // with C structs, unions, and enums when looking for a matching 2950 // tag declaration or definition. See the similar lookup tweak 2951 // in Sema::LookupName; is there a better way to deal with this? 2952 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2953 SearchDC = SearchDC->getParent(); 2954 } 2955 } 2956 2957 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2958 // Maybe we will complain about the shadowed template parameter. 2959 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2960 // Just pretend that we didn't see the previous declaration. 2961 PrevDecl = 0; 2962 } 2963 2964 if (PrevDecl) { 2965 // Check whether the previous declaration is usable. 2966 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 2967 2968 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2969 // If this is a use of a previous tag, or if the tag is already declared 2970 // in the same scope (so that the definition/declaration completes or 2971 // rementions the tag), reuse the decl. 2972 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2973 // Make sure that this wasn't declared as an enum and now used as a 2974 // struct or something similar. 2975 if (PrevTagDecl->getTagKind() != Kind) { 2976 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2977 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2978 // Recover by making this an anonymous redefinition. 2979 Name = 0; 2980 PrevDecl = 0; 2981 Invalid = true; 2982 } else { 2983 // If this is a use, just return the declaration we found. 2984 2985 // FIXME: In the future, return a variant or some other clue 2986 // for the consumer of this Decl to know it doesn't own it. 2987 // For our current ASTs this shouldn't be a problem, but will 2988 // need to be changed with DeclGroups. 2989 if (TK == TK_Reference) 2990 return PrevDecl; 2991 2992 // Diagnose attempts to redefine a tag. 2993 if (TK == TK_Definition) { 2994 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2995 Diag(NameLoc, diag::err_redefinition) << Name; 2996 Diag(Def->getLocation(), diag::note_previous_definition); 2997 // If this is a redefinition, recover by making this 2998 // struct be anonymous, which will make any later 2999 // references get the previous definition. 3000 Name = 0; 3001 PrevDecl = 0; 3002 Invalid = true; 3003 } else { 3004 // If the type is currently being defined, complain 3005 // about a nested redefinition. 3006 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3007 if (Tag->isBeingDefined()) { 3008 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3009 Diag(PrevTagDecl->getLocation(), 3010 diag::note_previous_definition); 3011 Name = 0; 3012 PrevDecl = 0; 3013 Invalid = true; 3014 } 3015 } 3016 3017 // Okay, this is definition of a previously declared or referenced 3018 // tag PrevDecl. We're going to create a new Decl for it. 3019 } 3020 } 3021 // If we get here we have (another) forward declaration or we 3022 // have a definition. Just create a new decl. 3023 } else { 3024 // If we get here, this is a definition of a new tag type in a nested 3025 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3026 // new decl/type. We set PrevDecl to NULL so that the entities 3027 // have distinct types. 3028 PrevDecl = 0; 3029 } 3030 // If we get here, we're going to create a new Decl. If PrevDecl 3031 // is non-NULL, it's a definition of the tag declared by 3032 // PrevDecl. If it's NULL, we have a new definition. 3033 } else { 3034 // PrevDecl is a namespace, template, or anything else 3035 // that lives in the IDNS_Tag identifier namespace. 3036 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3037 // The tag name clashes with a namespace name, issue an error and 3038 // recover by making this tag be anonymous. 3039 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3040 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3041 Name = 0; 3042 PrevDecl = 0; 3043 Invalid = true; 3044 } else { 3045 // The existing declaration isn't relevant to us; we're in a 3046 // new scope, so clear out the previous declaration. 3047 PrevDecl = 0; 3048 } 3049 } 3050 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3051 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3052 // C.scope.pdecl]p5: 3053 // -- for an elaborated-type-specifier of the form 3054 // 3055 // class-key identifier 3056 // 3057 // if the elaborated-type-specifier is used in the 3058 // decl-specifier-seq or parameter-declaration-clause of a 3059 // function defined in namespace scope, the identifier is 3060 // declared as a class-name in the namespace that contains 3061 // the declaration; otherwise, except as a friend 3062 // declaration, the identifier is declared in the smallest 3063 // non-class, non-function-prototype scope that contains the 3064 // declaration. 3065 // 3066 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3067 // C structs and unions. 3068 // 3069 // GNU C also supports this behavior as part of its incomplete 3070 // enum types extension, while GNU C++ does not. 3071 // 3072 // Find the context where we'll be declaring the tag. 3073 // FIXME: We would like to maintain the current DeclContext as the 3074 // lexical context, 3075 while (SearchDC->isRecord()) 3076 SearchDC = SearchDC->getParent(); 3077 3078 // Find the scope where we'll be declaring the tag. 3079 while (S->isClassScope() || 3080 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3081 ((S->getFlags() & Scope::DeclScope) == 0) || 3082 (S->getEntity() && 3083 ((DeclContext *)S->getEntity())->isTransparentContext())) 3084 S = S->getParent(); 3085 } 3086 3087CreateNewDecl: 3088 3089 // If there is an identifier, use the location of the identifier as the 3090 // location of the decl, otherwise use the location of the struct/union 3091 // keyword. 3092 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3093 3094 // Otherwise, create a new declaration. If there is a previous 3095 // declaration of the same entity, the two will be linked via 3096 // PrevDecl. 3097 TagDecl *New; 3098 3099 if (Kind == TagDecl::TK_enum) { 3100 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3101 // enum X { A, B, C } D; D should chain to X. 3102 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3103 cast_or_null<EnumDecl>(PrevDecl)); 3104 // If this is an undefined enum, warn. 3105 if (TK != TK_Definition && !Invalid) { 3106 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3107 : diag::ext_forward_ref_enum; 3108 Diag(Loc, DK); 3109 } 3110 } else { 3111 // struct/union/class 3112 3113 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3114 // struct X { int A; } D; D should chain to X. 3115 if (getLangOptions().CPlusPlus) 3116 // FIXME: Look for a way to use RecordDecl for simple structs. 3117 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3118 cast_or_null<CXXRecordDecl>(PrevDecl)); 3119 else 3120 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3121 cast_or_null<RecordDecl>(PrevDecl)); 3122 } 3123 3124 if (Kind != TagDecl::TK_enum) { 3125 // Handle #pragma pack: if the #pragma pack stack has non-default 3126 // alignment, make up a packed attribute for this decl. These 3127 // attributes are checked when the ASTContext lays out the 3128 // structure. 3129 // 3130 // It is important for implementing the correct semantics that this 3131 // happen here (in act on tag decl). The #pragma pack stack is 3132 // maintained as a result of parser callbacks which can occur at 3133 // many points during the parsing of a struct declaration (because 3134 // the #pragma tokens are effectively skipped over during the 3135 // parsing of the struct). 3136 if (unsigned Alignment = getPragmaPackAlignment()) 3137 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3138 } 3139 3140 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3141 // C++ [dcl.typedef]p3: 3142 // [...] Similarly, in a given scope, a class or enumeration 3143 // shall not be declared with the same name as a typedef-name 3144 // that is declared in that scope and refers to a type other 3145 // than the class or enumeration itself. 3146 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3147 TypedefDecl *PrevTypedef = 0; 3148 if (Lookup.getKind() == LookupResult::Found) 3149 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3150 3151 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3152 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3153 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3154 Diag(Loc, diag::err_tag_definition_of_typedef) 3155 << Context.getTypeDeclType(New) 3156 << PrevTypedef->getUnderlyingType(); 3157 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3158 Invalid = true; 3159 } 3160 } 3161 3162 if (Invalid) 3163 New->setInvalidDecl(); 3164 3165 if (Attr) 3166 ProcessDeclAttributeList(New, Attr); 3167 3168 // If we're declaring or defining a tag in function prototype scope 3169 // in C, note that this type can only be used within the function. 3170 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3171 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3172 3173 // Set the lexical context. If the tag has a C++ scope specifier, the 3174 // lexical context will be different from the semantic context. 3175 New->setLexicalDeclContext(CurContext); 3176 3177 if (TK == TK_Definition) 3178 New->startDefinition(); 3179 3180 // If this has an identifier, add it to the scope stack. 3181 if (Name) { 3182 S = getNonFieldDeclScope(S); 3183 PushOnScopeChains(New, S); 3184 } else { 3185 CurContext->addDecl(New); 3186 } 3187 3188 return New; 3189} 3190 3191void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3192 AdjustDeclIfTemplate(TagD); 3193 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3194 3195 // Enter the tag context. 3196 PushDeclContext(S, Tag); 3197 3198 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3199 FieldCollector->StartClass(); 3200 3201 if (Record->getIdentifier()) { 3202 // C++ [class]p2: 3203 // [...] The class-name is also inserted into the scope of the 3204 // class itself; this is known as the injected-class-name. For 3205 // purposes of access checking, the injected-class-name is treated 3206 // as if it were a public member name. 3207 RecordDecl *InjectedClassName 3208 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3209 CurContext, Record->getLocation(), 3210 Record->getIdentifier(), Record); 3211 InjectedClassName->setImplicit(); 3212 PushOnScopeChains(InjectedClassName, S); 3213 } 3214 } 3215} 3216 3217void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3218 AdjustDeclIfTemplate(TagD); 3219 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3220 3221 if (isa<CXXRecordDecl>(Tag)) 3222 FieldCollector->FinishClass(); 3223 3224 // Exit this scope of this tag's definition. 3225 PopDeclContext(); 3226 3227 // Notify the consumer that we've defined a tag. 3228 Consumer.HandleTagDeclDefinition(Tag); 3229} 3230 3231bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3232 QualType FieldTy, const Expr *BitWidth) { 3233 // C99 6.7.2.1p4 - verify the field type. 3234 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3235 if (!FieldTy->isIntegralType()) { 3236 // Handle incomplete types with specific error. 3237 if (FieldTy->isIncompleteType()) 3238 return Diag(FieldLoc, diag::err_field_incomplete) 3239 << FieldTy << BitWidth->getSourceRange(); 3240 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3241 << FieldName << BitWidth->getSourceRange(); 3242 } 3243 3244 llvm::APSInt Value; 3245 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3246 return true; 3247 3248 // Zero-width bitfield is ok for anonymous field. 3249 if (Value == 0 && FieldName) 3250 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3251 3252 if (Value.isNegative()) 3253 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3254 3255 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3256 // FIXME: We won't need the 0 size once we check that the field type is valid. 3257 if (TypeSize && Value.getZExtValue() > TypeSize) 3258 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3259 << FieldName << (unsigned)TypeSize; 3260 3261 return false; 3262} 3263 3264/// ActOnField - Each field of a struct/union/class is passed into this in order 3265/// to create a FieldDecl object for it. 3266Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3267 SourceLocation DeclStart, 3268 Declarator &D, ExprTy *BitfieldWidth) { 3269 return HandleField(S, static_cast<RecordDecl*>(TagD), DeclStart, D, 3270 static_cast<Expr*>(BitfieldWidth)); 3271} 3272 3273/// HandleField - Analyze a field of a C struct or a C++ data member. 3274/// 3275FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3276 SourceLocation DeclStart, 3277 Declarator &D, Expr *BitWidth) { 3278 IdentifierInfo *II = D.getIdentifier(); 3279 SourceLocation Loc = DeclStart; 3280 if (II) Loc = D.getIdentifierLoc(); 3281 3282 QualType T = GetTypeForDeclarator(D, S); 3283 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3284 bool InvalidDecl = false; 3285 3286 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3287 // than a variably modified type. 3288 if (T->isVariablyModifiedType()) { 3289 bool SizeIsNegative; 3290 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3291 SizeIsNegative); 3292 if (!FixedTy.isNull()) { 3293 Diag(Loc, diag::warn_illegal_constant_array_size); 3294 T = FixedTy; 3295 } else { 3296 if (SizeIsNegative) 3297 Diag(Loc, diag::err_typecheck_negative_array_size); 3298 else 3299 Diag(Loc, diag::err_typecheck_field_variable_size); 3300 T = Context.IntTy; 3301 InvalidDecl = true; 3302 } 3303 } 3304 3305 if (BitWidth) { 3306 if (VerifyBitField(Loc, II, T, BitWidth)) { 3307 InvalidDecl = true; 3308 DeleteExpr(BitWidth); 3309 BitWidth = 0; 3310 } 3311 } else { 3312 // Not a bitfield. 3313 3314 // validate II. 3315 3316 } 3317 3318 FieldDecl *NewFD = FieldDecl::Create(Context, Record, 3319 Loc, II, T, BitWidth, 3320 D.getDeclSpec().getStorageClassSpec() == 3321 DeclSpec::SCS_mutable); 3322 3323 if (II) { 3324 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3325 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3326 && !isa<TagDecl>(PrevDecl)) { 3327 Diag(Loc, diag::err_duplicate_member) << II; 3328 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3329 NewFD->setInvalidDecl(); 3330 Record->setInvalidDecl(); 3331 } 3332 } 3333 3334 if (getLangOptions().CPlusPlus) { 3335 CheckExtraCXXDefaultArguments(D); 3336 if (!T->isPODType()) 3337 cast<CXXRecordDecl>(Record)->setPOD(false); 3338 } 3339 3340 ProcessDeclAttributes(NewFD, D); 3341 if (T.isObjCGCWeak()) 3342 Diag(Loc, diag::warn_attribute_weak_on_field); 3343 3344 if (D.getInvalidType() || InvalidDecl) 3345 NewFD->setInvalidDecl(); 3346 3347 if (II) { 3348 PushOnScopeChains(NewFD, S); 3349 } else 3350 Record->addDecl(NewFD); 3351 3352 return NewFD; 3353} 3354 3355/// TranslateIvarVisibility - Translate visibility from a token ID to an 3356/// AST enum value. 3357static ObjCIvarDecl::AccessControl 3358TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3359 switch (ivarVisibility) { 3360 default: assert(0 && "Unknown visitibility kind"); 3361 case tok::objc_private: return ObjCIvarDecl::Private; 3362 case tok::objc_public: return ObjCIvarDecl::Public; 3363 case tok::objc_protected: return ObjCIvarDecl::Protected; 3364 case tok::objc_package: return ObjCIvarDecl::Package; 3365 } 3366} 3367 3368/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3369/// in order to create an IvarDecl object for it. 3370Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3371 SourceLocation DeclStart, 3372 Declarator &D, ExprTy *BitfieldWidth, 3373 tok::ObjCKeywordKind Visibility) { 3374 3375 IdentifierInfo *II = D.getIdentifier(); 3376 Expr *BitWidth = (Expr*)BitfieldWidth; 3377 SourceLocation Loc = DeclStart; 3378 if (II) Loc = D.getIdentifierLoc(); 3379 3380 // FIXME: Unnamed fields can be handled in various different ways, for 3381 // example, unnamed unions inject all members into the struct namespace! 3382 3383 QualType T = GetTypeForDeclarator(D, S); 3384 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3385 bool InvalidDecl = false; 3386 3387 if (BitWidth) { 3388 // 6.7.2.1p3, 6.7.2.1p4 3389 if (VerifyBitField(Loc, II, T, BitWidth)) { 3390 InvalidDecl = true; 3391 DeleteExpr(BitWidth); 3392 BitWidth = 0; 3393 } 3394 } else { 3395 // Not a bitfield. 3396 3397 // validate II. 3398 3399 } 3400 3401 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3402 // than a variably modified type. 3403 if (T->isVariablyModifiedType()) { 3404 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3405 InvalidDecl = true; 3406 } 3407 3408 // Get the visibility (access control) for this ivar. 3409 ObjCIvarDecl::AccessControl ac = 3410 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3411 : ObjCIvarDecl::None; 3412 3413 // Construct the decl. 3414 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3415 (Expr *)BitfieldWidth); 3416 3417 if (II) { 3418 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3419 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3420 && !isa<TagDecl>(PrevDecl)) { 3421 Diag(Loc, diag::err_duplicate_member) << II; 3422 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3423 NewID->setInvalidDecl(); 3424 } 3425 } 3426 3427 // Process attributes attached to the ivar. 3428 ProcessDeclAttributes(NewID, D); 3429 3430 if (D.getInvalidType() || InvalidDecl) 3431 NewID->setInvalidDecl(); 3432 3433 if (II) { 3434 // FIXME: When interfaces are DeclContexts, we'll need to add 3435 // these to the interface. 3436 S->AddDecl(NewID); 3437 IdResolver.AddDecl(NewID); 3438 } 3439 3440 return NewID; 3441} 3442 3443void Sema::ActOnFields(Scope* S, 3444 SourceLocation RecLoc, DeclTy *RecDecl, 3445 DeclTy **Fields, unsigned NumFields, 3446 SourceLocation LBrac, SourceLocation RBrac, 3447 AttributeList *Attr) { 3448 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3449 assert(EnclosingDecl && "missing record or interface decl"); 3450 3451 // If the decl this is being inserted into is invalid, then it may be a 3452 // redeclaration or some other bogus case. Don't try to add fields to it. 3453 if (EnclosingDecl->isInvalidDecl()) { 3454 // FIXME: Deallocate fields? 3455 return; 3456 } 3457 3458 3459 // Verify that all the fields are okay. 3460 unsigned NumNamedMembers = 0; 3461 llvm::SmallVector<FieldDecl*, 32> RecFields; 3462 3463 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3464 for (unsigned i = 0; i != NumFields; ++i) { 3465 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3466 assert(FD && "missing field decl"); 3467 3468 // Get the type for the field. 3469 Type *FDTy = FD->getType().getTypePtr(); 3470 3471 if (!FD->isAnonymousStructOrUnion()) { 3472 // Remember all fields written by the user. 3473 RecFields.push_back(FD); 3474 } 3475 3476 // If the field is already invalid for some reason, don't emit more 3477 // diagnostics about it. 3478 if (FD->isInvalidDecl()) 3479 continue; 3480 3481 // C99 6.7.2.1p2 - A field may not be a function type. 3482 if (FDTy->isFunctionType()) { 3483 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3484 << FD->getDeclName(); 3485 FD->setInvalidDecl(); 3486 EnclosingDecl->setInvalidDecl(); 3487 continue; 3488 } 3489 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3490 if (FDTy->isIncompleteType()) { 3491 if (!Record) { // Incomplete ivar type is always an error. 3492 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3493 diag::err_field_incomplete); 3494 FD->setInvalidDecl(); 3495 EnclosingDecl->setInvalidDecl(); 3496 continue; 3497 } 3498 if (i != NumFields-1 || // ... that the last member ... 3499 !Record->isStruct() || // ... of a structure ... 3500 !FDTy->isArrayType()) { //... may have incomplete array type. 3501 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3502 diag::err_field_incomplete); 3503 FD->setInvalidDecl(); 3504 EnclosingDecl->setInvalidDecl(); 3505 continue; 3506 } 3507 if (NumNamedMembers < 1) { //... must have more than named member ... 3508 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3509 << FD->getDeclName(); 3510 FD->setInvalidDecl(); 3511 EnclosingDecl->setInvalidDecl(); 3512 continue; 3513 } 3514 // Okay, we have a legal flexible array member at the end of the struct. 3515 if (Record) 3516 Record->setHasFlexibleArrayMember(true); 3517 } 3518 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3519 /// field of another structure or the element of an array. 3520 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3521 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3522 // If this is a member of a union, then entire union becomes "flexible". 3523 if (Record && Record->isUnion()) { 3524 Record->setHasFlexibleArrayMember(true); 3525 } else { 3526 // If this is a struct/class and this is not the last element, reject 3527 // it. Note that GCC supports variable sized arrays in the middle of 3528 // structures. 3529 if (i != NumFields-1) { 3530 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3531 << FD->getDeclName(); 3532 FD->setInvalidDecl(); 3533 EnclosingDecl->setInvalidDecl(); 3534 continue; 3535 } 3536 // We support flexible arrays at the end of structs in other structs 3537 // as an extension. 3538 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3539 << FD->getDeclName(); 3540 if (Record) 3541 Record->setHasFlexibleArrayMember(true); 3542 } 3543 } 3544 } 3545 /// A field cannot be an Objective-c object 3546 if (FDTy->isObjCInterfaceType()) { 3547 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3548 FD->setInvalidDecl(); 3549 EnclosingDecl->setInvalidDecl(); 3550 continue; 3551 } 3552 // Keep track of the number of named members. 3553 if (FD->getIdentifier()) 3554 ++NumNamedMembers; 3555 } 3556 3557 // Okay, we successfully defined 'Record'. 3558 if (Record) { 3559 Record->completeDefinition(Context); 3560 } else { 3561 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3562 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3563 ID->setIVarList(ClsFields, RecFields.size(), Context); 3564 ID->setLocEnd(RBrac); 3565 3566 // Must enforce the rule that ivars in the base classes may not be 3567 // duplicates. 3568 if (ID->getSuperClass()) { 3569 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3570 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3571 ObjCIvarDecl* Ivar = (*IVI); 3572 IdentifierInfo *II = Ivar->getIdentifier(); 3573 ObjCIvarDecl* prevIvar = 3574 ID->getSuperClass()->lookupInstanceVariable(II); 3575 if (prevIvar) { 3576 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3577 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3578 } 3579 } 3580 } 3581 } else if (ObjCImplementationDecl *IMPDecl = 3582 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3583 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3584 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3585 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3586 } 3587 } 3588 3589 if (Attr) 3590 ProcessDeclAttributeList(Record, Attr); 3591} 3592 3593Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3594 DeclTy *lastEnumConst, 3595 SourceLocation IdLoc, IdentifierInfo *Id, 3596 SourceLocation EqualLoc, ExprTy *val) { 3597 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3598 EnumConstantDecl *LastEnumConst = 3599 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3600 Expr *Val = static_cast<Expr*>(val); 3601 3602 // The scope passed in may not be a decl scope. Zip up the scope tree until 3603 // we find one that is. 3604 S = getNonFieldDeclScope(S); 3605 3606 // Verify that there isn't already something declared with this name in this 3607 // scope. 3608 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3609 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3610 // Maybe we will complain about the shadowed template parameter. 3611 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3612 // Just pretend that we didn't see the previous declaration. 3613 PrevDecl = 0; 3614 } 3615 3616 if (PrevDecl) { 3617 // When in C++, we may get a TagDecl with the same name; in this case the 3618 // enum constant will 'hide' the tag. 3619 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3620 "Received TagDecl when not in C++!"); 3621 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3622 if (isa<EnumConstantDecl>(PrevDecl)) 3623 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3624 else 3625 Diag(IdLoc, diag::err_redefinition) << Id; 3626 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3627 if (Val) Val->Destroy(Context); 3628 return 0; 3629 } 3630 } 3631 3632 llvm::APSInt EnumVal(32); 3633 QualType EltTy; 3634 if (Val) { 3635 // Make sure to promote the operand type to int. 3636 UsualUnaryConversions(Val); 3637 3638 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3639 SourceLocation ExpLoc; 3640 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3641 Val->Destroy(Context); 3642 Val = 0; // Just forget about it. 3643 } else { 3644 EltTy = Val->getType(); 3645 } 3646 } 3647 3648 if (!Val) { 3649 if (LastEnumConst) { 3650 // Assign the last value + 1. 3651 EnumVal = LastEnumConst->getInitVal(); 3652 ++EnumVal; 3653 3654 // Check for overflow on increment. 3655 if (EnumVal < LastEnumConst->getInitVal()) 3656 Diag(IdLoc, diag::warn_enum_value_overflow); 3657 3658 EltTy = LastEnumConst->getType(); 3659 } else { 3660 // First value, set to zero. 3661 EltTy = Context.IntTy; 3662 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3663 } 3664 } 3665 3666 EnumConstantDecl *New = 3667 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3668 Val, EnumVal); 3669 3670 // Register this decl in the current scope stack. 3671 PushOnScopeChains(New, S); 3672 3673 return New; 3674} 3675 3676// FIXME: For consistency with ActOnFields(), we should have the parser 3677// pass in the source location for the left/right braces. 3678void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3679 DeclTy **Elements, unsigned NumElements) { 3680 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3681 QualType EnumType = Context.getTypeDeclType(Enum); 3682 3683 // TODO: If the result value doesn't fit in an int, it must be a long or long 3684 // long value. ISO C does not support this, but GCC does as an extension, 3685 // emit a warning. 3686 unsigned IntWidth = Context.Target.getIntWidth(); 3687 3688 // Verify that all the values are okay, compute the size of the values, and 3689 // reverse the list. 3690 unsigned NumNegativeBits = 0; 3691 unsigned NumPositiveBits = 0; 3692 3693 // Keep track of whether all elements have type int. 3694 bool AllElementsInt = true; 3695 3696 for (unsigned i = 0; i != NumElements; ++i) { 3697 EnumConstantDecl *ECD = 3698 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3699 if (!ECD) continue; // Already issued a diagnostic. 3700 3701 // If the enum value doesn't fit in an int, emit an extension warning. 3702 const llvm::APSInt &InitVal = ECD->getInitVal(); 3703 assert(InitVal.getBitWidth() >= IntWidth && 3704 "Should have promoted value to int"); 3705 if (InitVal.getBitWidth() > IntWidth) { 3706 llvm::APSInt V(InitVal); 3707 V.trunc(IntWidth); 3708 V.extend(InitVal.getBitWidth()); 3709 if (V != InitVal) 3710 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3711 << InitVal.toString(10); 3712 } 3713 3714 // Keep track of the size of positive and negative values. 3715 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3716 NumPositiveBits = std::max(NumPositiveBits, 3717 (unsigned)InitVal.getActiveBits()); 3718 else 3719 NumNegativeBits = std::max(NumNegativeBits, 3720 (unsigned)InitVal.getMinSignedBits()); 3721 3722 // Keep track of whether every enum element has type int (very commmon). 3723 if (AllElementsInt) 3724 AllElementsInt = ECD->getType() == Context.IntTy; 3725 } 3726 3727 // Figure out the type that should be used for this enum. 3728 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3729 QualType BestType; 3730 unsigned BestWidth; 3731 3732 if (NumNegativeBits) { 3733 // If there is a negative value, figure out the smallest integer type (of 3734 // int/long/longlong) that fits. 3735 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3736 BestType = Context.IntTy; 3737 BestWidth = IntWidth; 3738 } else { 3739 BestWidth = Context.Target.getLongWidth(); 3740 3741 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3742 BestType = Context.LongTy; 3743 else { 3744 BestWidth = Context.Target.getLongLongWidth(); 3745 3746 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3747 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3748 BestType = Context.LongLongTy; 3749 } 3750 } 3751 } else { 3752 // If there is no negative value, figure out which of uint, ulong, ulonglong 3753 // fits. 3754 if (NumPositiveBits <= IntWidth) { 3755 BestType = Context.UnsignedIntTy; 3756 BestWidth = IntWidth; 3757 } else if (NumPositiveBits <= 3758 (BestWidth = Context.Target.getLongWidth())) { 3759 BestType = Context.UnsignedLongTy; 3760 } else { 3761 BestWidth = Context.Target.getLongLongWidth(); 3762 assert(NumPositiveBits <= BestWidth && 3763 "How could an initializer get larger than ULL?"); 3764 BestType = Context.UnsignedLongLongTy; 3765 } 3766 } 3767 3768 // Loop over all of the enumerator constants, changing their types to match 3769 // the type of the enum if needed. 3770 for (unsigned i = 0; i != NumElements; ++i) { 3771 EnumConstantDecl *ECD = 3772 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3773 if (!ECD) continue; // Already issued a diagnostic. 3774 3775 // Standard C says the enumerators have int type, but we allow, as an 3776 // extension, the enumerators to be larger than int size. If each 3777 // enumerator value fits in an int, type it as an int, otherwise type it the 3778 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3779 // that X has type 'int', not 'unsigned'. 3780 if (ECD->getType() == Context.IntTy) { 3781 // Make sure the init value is signed. 3782 llvm::APSInt IV = ECD->getInitVal(); 3783 IV.setIsSigned(true); 3784 ECD->setInitVal(IV); 3785 3786 if (getLangOptions().CPlusPlus) 3787 // C++ [dcl.enum]p4: Following the closing brace of an 3788 // enum-specifier, each enumerator has the type of its 3789 // enumeration. 3790 ECD->setType(EnumType); 3791 continue; // Already int type. 3792 } 3793 3794 // Determine whether the value fits into an int. 3795 llvm::APSInt InitVal = ECD->getInitVal(); 3796 bool FitsInInt; 3797 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3798 FitsInInt = InitVal.getActiveBits() < IntWidth; 3799 else 3800 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3801 3802 // If it fits into an integer type, force it. Otherwise force it to match 3803 // the enum decl type. 3804 QualType NewTy; 3805 unsigned NewWidth; 3806 bool NewSign; 3807 if (FitsInInt) { 3808 NewTy = Context.IntTy; 3809 NewWidth = IntWidth; 3810 NewSign = true; 3811 } else if (ECD->getType() == BestType) { 3812 // Already the right type! 3813 if (getLangOptions().CPlusPlus) 3814 // C++ [dcl.enum]p4: Following the closing brace of an 3815 // enum-specifier, each enumerator has the type of its 3816 // enumeration. 3817 ECD->setType(EnumType); 3818 continue; 3819 } else { 3820 NewTy = BestType; 3821 NewWidth = BestWidth; 3822 NewSign = BestType->isSignedIntegerType(); 3823 } 3824 3825 // Adjust the APSInt value. 3826 InitVal.extOrTrunc(NewWidth); 3827 InitVal.setIsSigned(NewSign); 3828 ECD->setInitVal(InitVal); 3829 3830 // Adjust the Expr initializer and type. 3831 if (ECD->getInitExpr()) 3832 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3833 /*isLvalue=*/false)); 3834 if (getLangOptions().CPlusPlus) 3835 // C++ [dcl.enum]p4: Following the closing brace of an 3836 // enum-specifier, each enumerator has the type of its 3837 // enumeration. 3838 ECD->setType(EnumType); 3839 else 3840 ECD->setType(NewTy); 3841 } 3842 3843 Enum->completeDefinition(Context, BestType); 3844} 3845 3846Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3847 ExprArg expr) { 3848 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3849 3850 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3851} 3852 3853