SemaDecl.cpp revision 4843e584b54460973b8445d38907bab0401ebb0c
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 RequireCompleteType(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 if (getLangOptions().CPlusPlus || 927 Record->getDeclContext()->isRecord()) 928 return BuildAnonymousStructOrUnion(S, DS, Record); 929 930 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 931 << DS.getSourceRange(); 932 } 933 934 // Microsoft allows unnamed struct/union fields. Don't complain 935 // about them. 936 // FIXME: Should we support Microsoft's extensions in this area? 937 if (Record->getDeclName() && getLangOptions().Microsoft) 938 return Tag; 939 } 940 941 if (!DS.isMissingDeclaratorOk() && 942 DS.getTypeSpecType() != DeclSpec::TST_error) { 943 // Warn about typedefs of enums without names, since this is an 944 // extension in both Microsoft an GNU. 945 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 946 Tag && isa<EnumDecl>(Tag)) { 947 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 948 << DS.getSourceRange(); 949 return Tag; 950 } 951 952 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 953 << DS.getSourceRange(); 954 return 0; 955 } 956 957 return Tag; 958} 959 960/// InjectAnonymousStructOrUnionMembers - Inject the members of the 961/// anonymous struct or union AnonRecord into the owning context Owner 962/// and scope S. This routine will be invoked just after we realize 963/// that an unnamed union or struct is actually an anonymous union or 964/// struct, e.g., 965/// 966/// @code 967/// union { 968/// int i; 969/// float f; 970/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 971/// // f into the surrounding scope.x 972/// @endcode 973/// 974/// This routine is recursive, injecting the names of nested anonymous 975/// structs/unions into the owning context and scope as well. 976bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 977 RecordDecl *AnonRecord) { 978 bool Invalid = false; 979 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 980 FEnd = AnonRecord->field_end(); 981 F != FEnd; ++F) { 982 if ((*F)->getDeclName()) { 983 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 984 LookupOrdinaryName, true); 985 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 986 // C++ [class.union]p2: 987 // The names of the members of an anonymous union shall be 988 // distinct from the names of any other entity in the 989 // scope in which the anonymous union is declared. 990 unsigned diagKind 991 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 992 : diag::err_anonymous_struct_member_redecl; 993 Diag((*F)->getLocation(), diagKind) 994 << (*F)->getDeclName(); 995 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 996 Invalid = true; 997 } else { 998 // C++ [class.union]p2: 999 // For the purpose of name lookup, after the anonymous union 1000 // definition, the members of the anonymous union are 1001 // considered to have been defined in the scope in which the 1002 // anonymous union is declared. 1003 Owner->makeDeclVisibleInContext(*F); 1004 S->AddDecl(*F); 1005 IdResolver.AddDecl(*F); 1006 } 1007 } else if (const RecordType *InnerRecordType 1008 = (*F)->getType()->getAsRecordType()) { 1009 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1010 if (InnerRecord->isAnonymousStructOrUnion()) 1011 Invalid = Invalid || 1012 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1013 } 1014 } 1015 1016 return Invalid; 1017} 1018 1019/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1020/// anonymous structure or union. Anonymous unions are a C++ feature 1021/// (C++ [class.union]) and a GNU C extension; anonymous structures 1022/// are a GNU C and GNU C++ extension. 1023Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1024 RecordDecl *Record) { 1025 DeclContext *Owner = Record->getDeclContext(); 1026 1027 // Diagnose whether this anonymous struct/union is an extension. 1028 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1029 Diag(Record->getLocation(), diag::ext_anonymous_union); 1030 else if (!Record->isUnion()) 1031 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1032 1033 // C and C++ require different kinds of checks for anonymous 1034 // structs/unions. 1035 bool Invalid = false; 1036 if (getLangOptions().CPlusPlus) { 1037 const char* PrevSpec = 0; 1038 // C++ [class.union]p3: 1039 // Anonymous unions declared in a named namespace or in the 1040 // global namespace shall be declared static. 1041 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1042 (isa<TranslationUnitDecl>(Owner) || 1043 (isa<NamespaceDecl>(Owner) && 1044 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1045 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1046 Invalid = true; 1047 1048 // Recover by adding 'static'. 1049 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1050 } 1051 // C++ [class.union]p3: 1052 // A storage class is not allowed in a declaration of an 1053 // anonymous union in a class scope. 1054 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1055 isa<RecordDecl>(Owner)) { 1056 Diag(DS.getStorageClassSpecLoc(), 1057 diag::err_anonymous_union_with_storage_spec); 1058 Invalid = true; 1059 1060 // Recover by removing the storage specifier. 1061 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1062 PrevSpec); 1063 } 1064 1065 // C++ [class.union]p2: 1066 // The member-specification of an anonymous union shall only 1067 // define non-static data members. [Note: nested types and 1068 // functions cannot be declared within an anonymous union. ] 1069 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1070 MemEnd = Record->decls_end(); 1071 Mem != MemEnd; ++Mem) { 1072 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1073 // C++ [class.union]p3: 1074 // An anonymous union shall not have private or protected 1075 // members (clause 11). 1076 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1077 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1078 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1079 Invalid = true; 1080 } 1081 } else if ((*Mem)->isImplicit()) { 1082 // Any implicit members are fine. 1083 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1084 // This is a type that showed up in an 1085 // elaborated-type-specifier inside the anonymous struct or 1086 // union, but which actually declares a type outside of the 1087 // anonymous struct or union. It's okay. 1088 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1089 if (!MemRecord->isAnonymousStructOrUnion() && 1090 MemRecord->getDeclName()) { 1091 // This is a nested type declaration. 1092 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1093 << (int)Record->isUnion(); 1094 Invalid = true; 1095 } 1096 } else { 1097 // We have something that isn't a non-static data 1098 // member. Complain about it. 1099 unsigned DK = diag::err_anonymous_record_bad_member; 1100 if (isa<TypeDecl>(*Mem)) 1101 DK = diag::err_anonymous_record_with_type; 1102 else if (isa<FunctionDecl>(*Mem)) 1103 DK = diag::err_anonymous_record_with_function; 1104 else if (isa<VarDecl>(*Mem)) 1105 DK = diag::err_anonymous_record_with_static; 1106 Diag((*Mem)->getLocation(), DK) 1107 << (int)Record->isUnion(); 1108 Invalid = true; 1109 } 1110 } 1111 } 1112 1113 if (!Record->isUnion() && !Owner->isRecord()) { 1114 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1115 << (int)getLangOptions().CPlusPlus; 1116 Invalid = true; 1117 } 1118 1119 // Create a declaration for this anonymous struct/union. 1120 NamedDecl *Anon = 0; 1121 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1122 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1123 /*IdentifierInfo=*/0, 1124 Context.getTypeDeclType(Record), 1125 /*BitWidth=*/0, /*Mutable=*/false); 1126 Anon->setAccess(AS_public); 1127 if (getLangOptions().CPlusPlus) 1128 FieldCollector->Add(cast<FieldDecl>(Anon)); 1129 } else { 1130 VarDecl::StorageClass SC; 1131 switch (DS.getStorageClassSpec()) { 1132 default: assert(0 && "Unknown storage class!"); 1133 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1134 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1135 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1136 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1137 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1138 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1139 case DeclSpec::SCS_mutable: 1140 // mutable can only appear on non-static class members, so it's always 1141 // an error here 1142 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1143 Invalid = true; 1144 SC = VarDecl::None; 1145 break; 1146 } 1147 1148 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1149 /*IdentifierInfo=*/0, 1150 Context.getTypeDeclType(Record), 1151 SC, DS.getSourceRange().getBegin()); 1152 } 1153 Anon->setImplicit(); 1154 1155 // Add the anonymous struct/union object to the current 1156 // context. We'll be referencing this object when we refer to one of 1157 // its members. 1158 Owner->addDecl(Anon); 1159 1160 // Inject the members of the anonymous struct/union into the owning 1161 // context and into the identifier resolver chain for name lookup 1162 // purposes. 1163 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1164 Invalid = true; 1165 1166 // Mark this as an anonymous struct/union type. Note that we do not 1167 // do this until after we have already checked and injected the 1168 // members of this anonymous struct/union type, because otherwise 1169 // the members could be injected twice: once by DeclContext when it 1170 // builds its lookup table, and once by 1171 // InjectAnonymousStructOrUnionMembers. 1172 Record->setAnonymousStructOrUnion(true); 1173 1174 if (Invalid) 1175 Anon->setInvalidDecl(); 1176 1177 return Anon; 1178} 1179 1180 1181/// GetNameForDeclarator - Determine the full declaration name for the 1182/// given Declarator. 1183DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1184 switch (D.getKind()) { 1185 case Declarator::DK_Abstract: 1186 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1187 return DeclarationName(); 1188 1189 case Declarator::DK_Normal: 1190 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1191 return DeclarationName(D.getIdentifier()); 1192 1193 case Declarator::DK_Constructor: { 1194 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1195 Ty = Context.getCanonicalType(Ty); 1196 return Context.DeclarationNames.getCXXConstructorName(Ty); 1197 } 1198 1199 case Declarator::DK_Destructor: { 1200 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1201 Ty = Context.getCanonicalType(Ty); 1202 return Context.DeclarationNames.getCXXDestructorName(Ty); 1203 } 1204 1205 case Declarator::DK_Conversion: { 1206 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1207 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1208 Ty = Context.getCanonicalType(Ty); 1209 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1210 } 1211 1212 case Declarator::DK_Operator: 1213 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1214 return Context.DeclarationNames.getCXXOperatorName( 1215 D.getOverloadedOperator()); 1216 } 1217 1218 assert(false && "Unknown name kind"); 1219 return DeclarationName(); 1220} 1221 1222/// isNearlyMatchingFunction - Determine whether the C++ functions 1223/// Declaration and Definition are "nearly" matching. This heuristic 1224/// is used to improve diagnostics in the case where an out-of-line 1225/// function definition doesn't match any declaration within 1226/// the class or namespace. 1227static bool isNearlyMatchingFunction(ASTContext &Context, 1228 FunctionDecl *Declaration, 1229 FunctionDecl *Definition) { 1230 if (Declaration->param_size() != Definition->param_size()) 1231 return false; 1232 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1233 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1234 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1235 1236 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1237 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1238 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1239 return false; 1240 } 1241 1242 return true; 1243} 1244 1245Sema::DeclTy * 1246Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1247 bool IsFunctionDefinition) { 1248 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1249 DeclarationName Name = GetNameForDeclarator(D); 1250 1251 // All of these full declarators require an identifier. If it doesn't have 1252 // one, the ParsedFreeStandingDeclSpec action should be used. 1253 if (!Name) { 1254 if (!D.getInvalidType()) // Reject this if we think it is valid. 1255 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1256 diag::err_declarator_need_ident) 1257 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1258 return 0; 1259 } 1260 1261 // The scope passed in may not be a decl scope. Zip up the scope tree until 1262 // we find one that is. 1263 while ((S->getFlags() & Scope::DeclScope) == 0 || 1264 (S->getFlags() & Scope::TemplateParamScope) != 0) 1265 S = S->getParent(); 1266 1267 DeclContext *DC; 1268 NamedDecl *PrevDecl; 1269 NamedDecl *New; 1270 bool InvalidDecl = false; 1271 1272 QualType R = GetTypeForDeclarator(D, S); 1273 if (R.isNull()) { 1274 InvalidDecl = true; 1275 R = Context.IntTy; 1276 } 1277 1278 // See if this is a redefinition of a variable in the same scope. 1279 if (D.getCXXScopeSpec().isInvalid()) { 1280 DC = CurContext; 1281 PrevDecl = 0; 1282 InvalidDecl = true; 1283 } else if (!D.getCXXScopeSpec().isSet()) { 1284 LookupNameKind NameKind = LookupOrdinaryName; 1285 1286 // If the declaration we're planning to build will be a function 1287 // or object with linkage, then look for another declaration with 1288 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1289 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1290 /* Do nothing*/; 1291 else if (R->isFunctionType()) { 1292 if (CurContext->isFunctionOrMethod()) 1293 NameKind = LookupRedeclarationWithLinkage; 1294 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1295 NameKind = LookupRedeclarationWithLinkage; 1296 1297 DC = CurContext; 1298 PrevDecl = LookupName(S, Name, NameKind, true, 1299 D.getDeclSpec().getStorageClassSpec() != 1300 DeclSpec::SCS_static, 1301 D.getIdentifierLoc()); 1302 } else { // Something like "int foo::x;" 1303 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1304 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1305 1306 // C++ 7.3.1.2p2: 1307 // Members (including explicit specializations of templates) of a named 1308 // namespace can also be defined outside that namespace by explicit 1309 // qualification of the name being defined, provided that the entity being 1310 // defined was already declared in the namespace and the definition appears 1311 // after the point of declaration in a namespace that encloses the 1312 // declarations namespace. 1313 // 1314 // Note that we only check the context at this point. We don't yet 1315 // have enough information to make sure that PrevDecl is actually 1316 // the declaration we want to match. For example, given: 1317 // 1318 // class X { 1319 // void f(); 1320 // void f(float); 1321 // }; 1322 // 1323 // void X::f(int) { } // ill-formed 1324 // 1325 // In this case, PrevDecl will point to the overload set 1326 // containing the two f's declared in X, but neither of them 1327 // matches. 1328 1329 // First check whether we named the global scope. 1330 if (isa<TranslationUnitDecl>(DC)) { 1331 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1332 << Name << D.getCXXScopeSpec().getRange(); 1333 } else if (!CurContext->Encloses(DC)) { 1334 // The qualifying scope doesn't enclose the original declaration. 1335 // Emit diagnostic based on current scope. 1336 SourceLocation L = D.getIdentifierLoc(); 1337 SourceRange R = D.getCXXScopeSpec().getRange(); 1338 if (isa<FunctionDecl>(CurContext)) 1339 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1340 else 1341 Diag(L, diag::err_invalid_declarator_scope) 1342 << Name << cast<NamedDecl>(DC) << R; 1343 InvalidDecl = true; 1344 } 1345 } 1346 1347 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1348 // Maybe we will complain about the shadowed template parameter. 1349 InvalidDecl = InvalidDecl 1350 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1351 // Just pretend that we didn't see the previous declaration. 1352 PrevDecl = 0; 1353 } 1354 1355 // In C++, the previous declaration we find might be a tag type 1356 // (class or enum). In this case, the new declaration will hide the 1357 // tag type. Note that this does does not apply if we're declaring a 1358 // typedef (C++ [dcl.typedef]p4). 1359 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1360 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1361 PrevDecl = 0; 1362 1363 bool Redeclaration = false; 1364 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1365 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1366 InvalidDecl, Redeclaration); 1367 } else if (R->isFunctionType()) { 1368 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1369 IsFunctionDefinition, InvalidDecl, 1370 Redeclaration); 1371 } else { 1372 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1373 InvalidDecl, Redeclaration); 1374 } 1375 1376 if (New == 0) 1377 return 0; 1378 1379 // Set the lexical context. If the declarator has a C++ scope specifier, the 1380 // lexical context will be different from the semantic context. 1381 New->setLexicalDeclContext(CurContext); 1382 1383 // If this has an identifier and is not an invalid redeclaration, 1384 // add it to the scope stack. 1385 if (Name && !(Redeclaration && InvalidDecl)) 1386 PushOnScopeChains(New, S); 1387 // If any semantic error occurred, mark the decl as invalid. 1388 if (D.getInvalidType() || InvalidDecl) 1389 New->setInvalidDecl(); 1390 1391 return New; 1392} 1393 1394/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1395/// types into constant array types in certain situations which would otherwise 1396/// be errors (for GCC compatibility). 1397static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1398 ASTContext &Context, 1399 bool &SizeIsNegative) { 1400 // This method tries to turn a variable array into a constant 1401 // array even when the size isn't an ICE. This is necessary 1402 // for compatibility with code that depends on gcc's buggy 1403 // constant expression folding, like struct {char x[(int)(char*)2];} 1404 SizeIsNegative = false; 1405 1406 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1407 QualType Pointee = PTy->getPointeeType(); 1408 QualType FixedType = 1409 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1410 if (FixedType.isNull()) return FixedType; 1411 FixedType = Context.getPointerType(FixedType); 1412 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1413 return FixedType; 1414 } 1415 1416 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1417 if (!VLATy) 1418 return QualType(); 1419 // FIXME: We should probably handle this case 1420 if (VLATy->getElementType()->isVariablyModifiedType()) 1421 return QualType(); 1422 1423 Expr::EvalResult EvalResult; 1424 if (!VLATy->getSizeExpr() || 1425 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1426 !EvalResult.Val.isInt()) 1427 return QualType(); 1428 1429 llvm::APSInt &Res = EvalResult.Val.getInt(); 1430 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1431 return Context.getConstantArrayType(VLATy->getElementType(), 1432 Res, ArrayType::Normal, 0); 1433 1434 SizeIsNegative = true; 1435 return QualType(); 1436} 1437 1438/// \brief Register the given locally-scoped external C declaration so 1439/// that it can be found later for redeclarations 1440void 1441Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1442 Scope *S) { 1443 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1444 "Decl is not a locally-scoped decl!"); 1445 // Note that we have a locally-scoped external with this name. 1446 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1447 1448 if (!PrevDecl) 1449 return; 1450 1451 // If there was a previous declaration of this variable, it may be 1452 // in our identifier chain. Update the identifier chain with the new 1453 // declaration. 1454 if (IdResolver.ReplaceDecl(PrevDecl, ND)) { 1455 // The previous declaration was found on the identifer resolver 1456 // chain, so remove it from its scope. 1457 while (S && !S->isDeclScope(PrevDecl)) 1458 S = S->getParent(); 1459 1460 if (S) 1461 S->RemoveDecl(PrevDecl); 1462 } 1463} 1464 1465NamedDecl* 1466Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1467 QualType R, Decl* LastDeclarator, 1468 Decl* PrevDecl, bool& InvalidDecl, 1469 bool &Redeclaration) { 1470 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1471 if (D.getCXXScopeSpec().isSet()) { 1472 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1473 << D.getCXXScopeSpec().getRange(); 1474 InvalidDecl = true; 1475 // Pretend we didn't see the scope specifier. 1476 DC = 0; 1477 } 1478 1479 // Check that there are no default arguments (C++ only). 1480 if (getLangOptions().CPlusPlus) 1481 CheckExtraCXXDefaultArguments(D); 1482 1483 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1484 if (!NewTD) return 0; 1485 1486 // Handle attributes prior to checking for duplicates in MergeVarDecl 1487 ProcessDeclAttributes(NewTD, D); 1488 // Merge the decl with the existing one if appropriate. If the decl is 1489 // in an outer scope, it isn't the same thing. 1490 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1491 Redeclaration = true; 1492 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1493 InvalidDecl = true; 1494 } 1495 1496 if (S->getFnParent() == 0) { 1497 QualType T = NewTD->getUnderlyingType(); 1498 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1499 // then it shall have block scope. 1500 if (T->isVariablyModifiedType()) { 1501 bool SizeIsNegative; 1502 QualType FixedTy = 1503 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1504 if (!FixedTy.isNull()) { 1505 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1506 NewTD->setUnderlyingType(FixedTy); 1507 } else { 1508 if (SizeIsNegative) 1509 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1510 else if (T->isVariableArrayType()) 1511 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1512 else 1513 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1514 InvalidDecl = true; 1515 } 1516 } 1517 } 1518 return NewTD; 1519} 1520 1521/// \brief Determines whether the given declaration is an out-of-scope 1522/// previous declaration. 1523/// 1524/// This routine should be invoked when name lookup has found a 1525/// previous declaration (PrevDecl) that is not in the scope where a 1526/// new declaration by the same name is being introduced. If the new 1527/// declaration occurs in a local scope, previous declarations with 1528/// linkage may still be considered previous declarations (C99 1529/// 6.2.2p4-5, C++ [basic.link]p6). 1530/// 1531/// \param PrevDecl the previous declaration found by name 1532/// lookup 1533/// 1534/// \param DC the context in which the new declaration is being 1535/// declared. 1536/// 1537/// \returns true if PrevDecl is an out-of-scope previous declaration 1538/// for a new delcaration with the same name. 1539static bool 1540isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1541 ASTContext &Context) { 1542 if (!PrevDecl) 1543 return 0; 1544 1545 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1546 // case we need to check each of the overloaded functions. 1547 if (!PrevDecl->hasLinkage()) 1548 return false; 1549 1550 if (Context.getLangOptions().CPlusPlus) { 1551 // C++ [basic.link]p6: 1552 // If there is a visible declaration of an entity with linkage 1553 // having the same name and type, ignoring entities declared 1554 // outside the innermost enclosing namespace scope, the block 1555 // scope declaration declares that same entity and receives the 1556 // linkage of the previous declaration. 1557 DeclContext *OuterContext = DC->getLookupContext(); 1558 if (!OuterContext->isFunctionOrMethod()) 1559 // This rule only applies to block-scope declarations. 1560 return false; 1561 else { 1562 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1563 if (PrevOuterContext->isRecord()) 1564 // We found a member function: ignore it. 1565 return false; 1566 else { 1567 // Find the innermost enclosing namespace for the new and 1568 // previous declarations. 1569 while (!OuterContext->isFileContext()) 1570 OuterContext = OuterContext->getParent(); 1571 while (!PrevOuterContext->isFileContext()) 1572 PrevOuterContext = PrevOuterContext->getParent(); 1573 1574 // The previous declaration is in a different namespace, so it 1575 // isn't the same function. 1576 if (OuterContext->getPrimaryContext() != 1577 PrevOuterContext->getPrimaryContext()) 1578 return false; 1579 } 1580 } 1581 } 1582 1583 return true; 1584} 1585 1586NamedDecl* 1587Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1588 QualType R, Decl* LastDeclarator, 1589 NamedDecl* PrevDecl, bool& InvalidDecl, 1590 bool &Redeclaration) { 1591 DeclarationName Name = GetNameForDeclarator(D); 1592 1593 // Check that there are no default arguments (C++ only). 1594 if (getLangOptions().CPlusPlus) 1595 CheckExtraCXXDefaultArguments(D); 1596 1597 if (R.getTypePtr()->isObjCInterfaceType()) { 1598 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object); 1599 InvalidDecl = true; 1600 } 1601 1602 VarDecl *NewVD; 1603 VarDecl::StorageClass SC; 1604 switch (D.getDeclSpec().getStorageClassSpec()) { 1605 default: assert(0 && "Unknown storage class!"); 1606 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1607 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1608 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1609 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1610 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1611 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1612 case DeclSpec::SCS_mutable: 1613 // mutable can only appear on non-static class members, so it's always 1614 // an error here 1615 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1616 InvalidDecl = true; 1617 SC = VarDecl::None; 1618 break; 1619 } 1620 1621 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1622 if (!II) { 1623 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1624 << Name.getAsString(); 1625 return 0; 1626 } 1627 1628 if (DC->isRecord()) { 1629 // This is a static data member for a C++ class. 1630 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1631 D.getIdentifierLoc(), II, 1632 R); 1633 } else { 1634 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1635 if (S->getFnParent() == 0) { 1636 // C99 6.9p2: The storage-class specifiers auto and register shall not 1637 // appear in the declaration specifiers in an external declaration. 1638 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1639 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1640 InvalidDecl = true; 1641 } 1642 } 1643 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1644 II, R, SC, 1645 // FIXME: Move to DeclGroup... 1646 D.getDeclSpec().getSourceRange().getBegin()); 1647 NewVD->setThreadSpecified(ThreadSpecified); 1648 } 1649 NewVD->setNextDeclarator(LastDeclarator); 1650 1651 // Handle attributes prior to checking for duplicates in MergeVarDecl 1652 ProcessDeclAttributes(NewVD, D); 1653 1654 // Handle GNU asm-label extension (encoded as an attribute). 1655 if (Expr *E = (Expr*) D.getAsmLabel()) { 1656 // The parser guarantees this is a string. 1657 StringLiteral *SE = cast<StringLiteral>(E); 1658 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1659 SE->getByteLength()))); 1660 } 1661 1662 // Emit an error if an address space was applied to decl with local storage. 1663 // This includes arrays of objects with address space qualifiers, but not 1664 // automatic variables that point to other address spaces. 1665 // ISO/IEC TR 18037 S5.1.2 1666 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1667 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1668 InvalidDecl = true; 1669 } 1670 1671 if (NewVD->hasLocalStorage() && NewVD->getType().isObjCGCWeak()) { 1672 Diag(D.getIdentifierLoc(), diag::warn_attribute_weak_on_local); 1673 } 1674 1675 bool isIllegalVLA = R->isVariableArrayType() && NewVD->hasGlobalStorage(); 1676 bool isIllegalVM = R->isVariablyModifiedType() && NewVD->hasLinkage(); 1677 if (isIllegalVLA || isIllegalVM) { 1678 bool SizeIsNegative; 1679 QualType FixedTy = 1680 TryToFixInvalidVariablyModifiedType(R, Context, SizeIsNegative); 1681 if (!FixedTy.isNull()) { 1682 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1683 NewVD->setType(FixedTy); 1684 } else if (R->isVariableArrayType()) { 1685 NewVD->setInvalidDecl(); 1686 1687 const VariableArrayType *VAT = Context.getAsVariableArrayType(R); 1688 // FIXME: This won't give the correct result for 1689 // int a[10][n]; 1690 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1691 1692 if (NewVD->isFileVarDecl()) 1693 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1694 << SizeRange; 1695 else if (NewVD->getStorageClass() == VarDecl::Static) 1696 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1697 << SizeRange; 1698 else 1699 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1700 << SizeRange; 1701 } else { 1702 InvalidDecl = true; 1703 1704 if (NewVD->isFileVarDecl()) 1705 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1706 else 1707 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1708 } 1709 } 1710 1711 // If name lookup finds a previous declaration that is not in the 1712 // same scope as the new declaration, this may still be an 1713 // acceptable redeclaration. 1714 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1715 !(NewVD->hasLinkage() && 1716 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1717 PrevDecl = 0; 1718 1719 if (!PrevDecl && NewVD->isExternC(Context)) { 1720 // Since we did not find anything by this name and we're declaring 1721 // an extern "C" variable, look for a non-visible extern "C" 1722 // declaration with the same name. 1723 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1724 = LocallyScopedExternalDecls.find(Name); 1725 if (Pos != LocallyScopedExternalDecls.end()) 1726 PrevDecl = Pos->second; 1727 } 1728 1729 // Merge the decl with the existing one if appropriate. 1730 if (PrevDecl) { 1731 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1732 // The user tried to define a non-static data member 1733 // out-of-line (C++ [dcl.meaning]p1). 1734 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1735 << D.getCXXScopeSpec().getRange(); 1736 NewVD->Destroy(Context); 1737 return 0; 1738 } 1739 1740 Redeclaration = true; 1741 if (MergeVarDecl(NewVD, PrevDecl)) 1742 InvalidDecl = true; 1743 1744 if (D.getCXXScopeSpec().isSet()) { 1745 // No previous declaration in the qualifying scope. 1746 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1747 << Name << D.getCXXScopeSpec().getRange(); 1748 InvalidDecl = true; 1749 } 1750 } 1751 1752 // If this is a locally-scoped extern C variable, update the map of 1753 // such variables. 1754 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1755 !InvalidDecl) 1756 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1757 1758 return NewVD; 1759} 1760 1761NamedDecl* 1762Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1763 QualType R, Decl *LastDeclarator, 1764 NamedDecl* PrevDecl, bool IsFunctionDefinition, 1765 bool& InvalidDecl, bool &Redeclaration) { 1766 assert(R.getTypePtr()->isFunctionType()); 1767 1768 DeclarationName Name = GetNameForDeclarator(D); 1769 FunctionDecl::StorageClass SC = FunctionDecl::None; 1770 switch (D.getDeclSpec().getStorageClassSpec()) { 1771 default: assert(0 && "Unknown storage class!"); 1772 case DeclSpec::SCS_auto: 1773 case DeclSpec::SCS_register: 1774 case DeclSpec::SCS_mutable: 1775 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1776 diag::err_typecheck_sclass_func); 1777 InvalidDecl = true; 1778 break; 1779 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1780 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1781 case DeclSpec::SCS_static: { 1782 if (DC->getLookupContext()->isFunctionOrMethod()) { 1783 // C99 6.7.1p5: 1784 // The declaration of an identifier for a function that has 1785 // block scope shall have no explicit storage-class specifier 1786 // other than extern 1787 // See also (C++ [dcl.stc]p4). 1788 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1789 diag::err_static_block_func); 1790 SC = FunctionDecl::None; 1791 } else 1792 SC = FunctionDecl::Static; 1793 break; 1794 } 1795 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1796 } 1797 1798 bool isInline = D.getDeclSpec().isInlineSpecified(); 1799 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1800 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1801 1802 FunctionDecl *NewFD; 1803 if (D.getKind() == Declarator::DK_Constructor) { 1804 // This is a C++ constructor declaration. 1805 assert(DC->isRecord() && 1806 "Constructors can only be declared in a member context"); 1807 1808 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1809 1810 // Create the new declaration 1811 NewFD = CXXConstructorDecl::Create(Context, 1812 cast<CXXRecordDecl>(DC), 1813 D.getIdentifierLoc(), Name, R, 1814 isExplicit, isInline, 1815 /*isImplicitlyDeclared=*/false); 1816 1817 if (InvalidDecl) 1818 NewFD->setInvalidDecl(); 1819 } else if (D.getKind() == Declarator::DK_Destructor) { 1820 // This is a C++ destructor declaration. 1821 if (DC->isRecord()) { 1822 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1823 1824 NewFD = CXXDestructorDecl::Create(Context, 1825 cast<CXXRecordDecl>(DC), 1826 D.getIdentifierLoc(), Name, R, 1827 isInline, 1828 /*isImplicitlyDeclared=*/false); 1829 1830 if (InvalidDecl) 1831 NewFD->setInvalidDecl(); 1832 } else { 1833 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1834 1835 // Create a FunctionDecl to satisfy the function definition parsing 1836 // code path. 1837 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1838 Name, R, SC, isInline, 1839 /*hasPrototype=*/true, 1840 // FIXME: Move to DeclGroup... 1841 D.getDeclSpec().getSourceRange().getBegin()); 1842 InvalidDecl = true; 1843 NewFD->setInvalidDecl(); 1844 } 1845 } else if (D.getKind() == Declarator::DK_Conversion) { 1846 if (!DC->isRecord()) { 1847 Diag(D.getIdentifierLoc(), 1848 diag::err_conv_function_not_member); 1849 return 0; 1850 } else { 1851 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1852 1853 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1854 D.getIdentifierLoc(), Name, R, 1855 isInline, isExplicit); 1856 1857 if (InvalidDecl) 1858 NewFD->setInvalidDecl(); 1859 } 1860 } else if (DC->isRecord()) { 1861 // This is a C++ method declaration. 1862 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1863 D.getIdentifierLoc(), Name, R, 1864 (SC == FunctionDecl::Static), isInline); 1865 } else { 1866 NewFD = FunctionDecl::Create(Context, DC, 1867 D.getIdentifierLoc(), 1868 Name, R, SC, isInline, 1869 /*hasPrototype=*/ 1870 (getLangOptions().CPlusPlus || 1871 (D.getNumTypeObjects() && 1872 D.getTypeObject(0).Fun.hasPrototype)), 1873 // FIXME: Move to DeclGroup... 1874 D.getDeclSpec().getSourceRange().getBegin()); 1875 } 1876 NewFD->setNextDeclarator(LastDeclarator); 1877 1878 // Set the lexical context. If the declarator has a C++ 1879 // scope specifier, the lexical context will be different 1880 // from the semantic context. 1881 NewFD->setLexicalDeclContext(CurContext); 1882 1883 // Handle GNU asm-label extension (encoded as an attribute). 1884 if (Expr *E = (Expr*) D.getAsmLabel()) { 1885 // The parser guarantees this is a string. 1886 StringLiteral *SE = cast<StringLiteral>(E); 1887 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1888 SE->getByteLength()))); 1889 } 1890 1891 // Copy the parameter declarations from the declarator D to 1892 // the function declaration NewFD, if they are available. 1893 if (D.getNumTypeObjects() > 0) { 1894 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1895 1896 // Create Decl objects for each parameter, adding them to the 1897 // FunctionDecl. 1898 llvm::SmallVector<ParmVarDecl*, 16> Params; 1899 1900 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1901 // function that takes no arguments, not a function that takes a 1902 // single void argument. 1903 // We let through "const void" here because Sema::GetTypeForDeclarator 1904 // already checks for that case. 1905 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1906 FTI.ArgInfo[0].Param && 1907 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1908 // empty arg list, don't push any params. 1909 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1910 1911 // In C++, the empty parameter-type-list must be spelled "void"; a 1912 // typedef of void is not permitted. 1913 if (getLangOptions().CPlusPlus && 1914 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1915 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1916 } 1917 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1918 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1919 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1920 } 1921 1922 NewFD->setParams(Context, &Params[0], Params.size()); 1923 } else if (R->getAsTypedefType()) { 1924 // When we're declaring a function with a typedef, as in the 1925 // following example, we'll need to synthesize (unnamed) 1926 // parameters for use in the declaration. 1927 // 1928 // @code 1929 // typedef void fn(int); 1930 // fn f; 1931 // @endcode 1932 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 1933 if (!FT) { 1934 // This is a typedef of a function with no prototype, so we 1935 // don't need to do anything. 1936 } else if ((FT->getNumArgs() == 0) || 1937 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1938 FT->getArgType(0)->isVoidType())) { 1939 // This is a zero-argument function. We don't need to do anything. 1940 } else { 1941 // Synthesize a parameter for each argument type. 1942 llvm::SmallVector<ParmVarDecl*, 16> Params; 1943 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 1944 ArgType != FT->arg_type_end(); ++ArgType) { 1945 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 1946 SourceLocation(), 0, 1947 *ArgType, VarDecl::None, 1948 0); 1949 Param->setImplicit(); 1950 Params.push_back(Param); 1951 } 1952 1953 NewFD->setParams(Context, &Params[0], Params.size()); 1954 } 1955 } 1956 1957 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1958 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1959 else if (isa<CXXDestructorDecl>(NewFD)) { 1960 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1961 Record->setUserDeclaredDestructor(true); 1962 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1963 // user-defined destructor. 1964 Record->setPOD(false); 1965 } else if (CXXConversionDecl *Conversion = 1966 dyn_cast<CXXConversionDecl>(NewFD)) 1967 ActOnConversionDeclarator(Conversion); 1968 1969 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1970 if (NewFD->isOverloadedOperator() && 1971 CheckOverloadedOperatorDeclaration(NewFD)) 1972 NewFD->setInvalidDecl(); 1973 1974 // If name lookup finds a previous declaration that is not in the 1975 // same scope as the new declaration, this may still be an 1976 // acceptable redeclaration. 1977 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1978 !(NewFD->hasLinkage() && 1979 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1980 PrevDecl = 0; 1981 1982 if (!PrevDecl && NewFD->isExternC(Context)) { 1983 // Since we did not find anything by this name and we're declaring 1984 // an extern "C" function, look for a non-visible extern "C" 1985 // declaration with the same name. 1986 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1987 = LocallyScopedExternalDecls.find(Name); 1988 if (Pos != LocallyScopedExternalDecls.end()) 1989 PrevDecl = Pos->second; 1990 } 1991 1992 // Merge or overload the declaration with an existing declaration of 1993 // the same name, if appropriate. 1994 bool OverloadableAttrRequired = false; 1995 if (PrevDecl) { 1996 // Determine whether NewFD is an overload of PrevDecl or 1997 // a declaration that requires merging. If it's an overload, 1998 // there's no more work to do here; we'll just add the new 1999 // function to the scope. 2000 OverloadedFunctionDecl::function_iterator MatchedDecl; 2001 2002 if (!getLangOptions().CPlusPlus && 2003 AllowOverloadingOfFunction(PrevDecl, Context)) { 2004 OverloadableAttrRequired = true; 2005 2006 // Functions marked "overloadable" must have a prototype (that 2007 // we can't get through declaration merging). 2008 if (!R->getAsFunctionProtoType()) { 2009 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2010 << NewFD; 2011 InvalidDecl = true; 2012 Redeclaration = true; 2013 2014 // Turn this into a variadic function with no parameters. 2015 R = Context.getFunctionType(R->getAsFunctionType()->getResultType(), 2016 0, 0, true, 0); 2017 NewFD->setType(R); 2018 } 2019 } 2020 2021 if (PrevDecl && 2022 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2023 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2024 Redeclaration = true; 2025 Decl *OldDecl = PrevDecl; 2026 2027 // If PrevDecl was an overloaded function, extract the 2028 // FunctionDecl that matched. 2029 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2030 OldDecl = *MatchedDecl; 2031 2032 // NewFD and PrevDecl represent declarations that need to be 2033 // merged. 2034 if (MergeFunctionDecl(NewFD, OldDecl)) 2035 InvalidDecl = true; 2036 2037 if (!InvalidDecl) { 2038 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2039 2040 // An out-of-line member function declaration must also be a 2041 // definition (C++ [dcl.meaning]p1). 2042 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 2043 !InvalidDecl) { 2044 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2045 << D.getCXXScopeSpec().getRange(); 2046 NewFD->setInvalidDecl(); 2047 } 2048 } 2049 } 2050 } 2051 2052 if (D.getCXXScopeSpec().isSet() && 2053 (!PrevDecl || !Redeclaration)) { 2054 // The user tried to provide an out-of-line definition for a 2055 // function that is a member of a class or namespace, but there 2056 // was no such member function declared (C++ [class.mfct]p2, 2057 // C++ [namespace.memdef]p2). For example: 2058 // 2059 // class X { 2060 // void f() const; 2061 // }; 2062 // 2063 // void X::f() { } // ill-formed 2064 // 2065 // Complain about this problem, and attempt to suggest close 2066 // matches (e.g., those that differ only in cv-qualifiers and 2067 // whether the parameter types are references). 2068 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2069 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2070 InvalidDecl = true; 2071 2072 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2073 true); 2074 assert(!Prev.isAmbiguous() && 2075 "Cannot have an ambiguity in previous-declaration lookup"); 2076 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2077 Func != FuncEnd; ++Func) { 2078 if (isa<FunctionDecl>(*Func) && 2079 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2080 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2081 } 2082 2083 PrevDecl = 0; 2084 } 2085 2086 // Handle attributes. We need to have merged decls when handling attributes 2087 // (for example to check for conflicts, etc). 2088 ProcessDeclAttributes(NewFD, D); 2089 AddKnownFunctionAttributes(NewFD); 2090 2091 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2092 // If a function name is overloadable in C, then every function 2093 // with that name must be marked "overloadable". 2094 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2095 << Redeclaration << NewFD; 2096 if (PrevDecl) 2097 Diag(PrevDecl->getLocation(), 2098 diag::note_attribute_overloadable_prev_overload); 2099 NewFD->addAttr(::new (Context) OverloadableAttr()); 2100 } 2101 2102 if (getLangOptions().CPlusPlus) { 2103 // In C++, check default arguments now that we have merged decls. Unless 2104 // the lexical context is the class, because in this case this is done 2105 // during delayed parsing anyway. 2106 if (!CurContext->isRecord()) 2107 CheckCXXDefaultArguments(NewFD); 2108 2109 // An out-of-line member function declaration must also be a 2110 // definition (C++ [dcl.meaning]p1). 2111 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2112 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2113 << D.getCXXScopeSpec().getRange(); 2114 InvalidDecl = true; 2115 } 2116 } 2117 2118 // If this is a locally-scoped extern C function, update the 2119 // map of such names. 2120 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2121 && !InvalidDecl) 2122 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2123 2124 return NewFD; 2125} 2126 2127bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2128 // FIXME: Need strict checking. In C89, we need to check for 2129 // any assignment, increment, decrement, function-calls, or 2130 // commas outside of a sizeof. In C99, it's the same list, 2131 // except that the aforementioned are allowed in unevaluated 2132 // expressions. Everything else falls under the 2133 // "may accept other forms of constant expressions" exception. 2134 // (We never end up here for C++, so the constant expression 2135 // rules there don't matter.) 2136 if (Init->isConstantInitializer(Context)) 2137 return false; 2138 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2139 << Init->getSourceRange(); 2140 return true; 2141} 2142 2143void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2144 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2145} 2146 2147/// AddInitializerToDecl - Adds the initializer Init to the 2148/// declaration dcl. If DirectInit is true, this is C++ direct 2149/// initialization rather than copy initialization. 2150void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2151 Decl *RealDecl = static_cast<Decl *>(dcl); 2152 // If there is no declaration, there was an error parsing it. Just ignore 2153 // the initializer. 2154 if (RealDecl == 0) 2155 return; 2156 2157 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2158 if (!VDecl) { 2159 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2160 RealDecl->setInvalidDecl(); 2161 return; 2162 } 2163 2164 // Take ownership of the expression, now that we're sure we have somewhere 2165 // to put it. 2166 Expr *Init = static_cast<Expr *>(init.release()); 2167 assert(Init && "missing initializer"); 2168 2169 // Get the decls type and save a reference for later, since 2170 // CheckInitializerTypes may change it. 2171 QualType DclT = VDecl->getType(), SavT = DclT; 2172 if (VDecl->isBlockVarDecl()) { 2173 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2174 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2175 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2176 VDecl->setInvalidDecl(); 2177 } else if (!VDecl->isInvalidDecl()) { 2178 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2179 VDecl->getDeclName(), DirectInit)) 2180 VDecl->setInvalidDecl(); 2181 2182 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2183 // Don't check invalid declarations to avoid emitting useless diagnostics. 2184 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2185 if (SC == VarDecl::Static) // C99 6.7.8p4. 2186 CheckForConstantInitializer(Init, DclT); 2187 } 2188 } 2189 } else if (VDecl->isFileVarDecl()) { 2190 if (VDecl->getStorageClass() == VarDecl::Extern) 2191 Diag(VDecl->getLocation(), diag::warn_extern_init); 2192 if (!VDecl->isInvalidDecl()) 2193 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2194 VDecl->getDeclName(), DirectInit)) 2195 VDecl->setInvalidDecl(); 2196 2197 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2198 // Don't check invalid declarations to avoid emitting useless diagnostics. 2199 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2200 // C99 6.7.8p4. All file scoped initializers need to be constant. 2201 CheckForConstantInitializer(Init, DclT); 2202 } 2203 } 2204 // If the type changed, it means we had an incomplete type that was 2205 // completed by the initializer. For example: 2206 // int ary[] = { 1, 3, 5 }; 2207 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2208 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2209 VDecl->setType(DclT); 2210 Init->setType(DclT); 2211 } 2212 2213 // Attach the initializer to the decl. 2214 VDecl->setInit(Init); 2215 return; 2216} 2217 2218void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2219 Decl *RealDecl = static_cast<Decl *>(dcl); 2220 2221 // If there is no declaration, there was an error parsing it. Just ignore it. 2222 if (RealDecl == 0) 2223 return; 2224 2225 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2226 QualType Type = Var->getType(); 2227 // C++ [dcl.init.ref]p3: 2228 // The initializer can be omitted for a reference only in a 2229 // parameter declaration (8.3.5), in the declaration of a 2230 // function return type, in the declaration of a class member 2231 // within its class declaration (9.2), and where the extern 2232 // specifier is explicitly used. 2233 if (Type->isReferenceType() && 2234 Var->getStorageClass() != VarDecl::Extern && 2235 Var->getStorageClass() != VarDecl::PrivateExtern) { 2236 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2237 << Var->getDeclName() 2238 << SourceRange(Var->getLocation(), Var->getLocation()); 2239 Var->setInvalidDecl(); 2240 return; 2241 } 2242 2243 // C++ [dcl.init]p9: 2244 // 2245 // If no initializer is specified for an object, and the object 2246 // is of (possibly cv-qualified) non-POD class type (or array 2247 // thereof), the object shall be default-initialized; if the 2248 // object is of const-qualified type, the underlying class type 2249 // shall have a user-declared default constructor. 2250 if (getLangOptions().CPlusPlus) { 2251 QualType InitType = Type; 2252 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2253 InitType = Array->getElementType(); 2254 if (Var->getStorageClass() != VarDecl::Extern && 2255 Var->getStorageClass() != VarDecl::PrivateExtern && 2256 InitType->isRecordType()) { 2257 const CXXConstructorDecl *Constructor = 0; 2258 if (!RequireCompleteType(Var->getLocation(), InitType, 2259 diag::err_invalid_incomplete_type_use)) 2260 Constructor 2261 = PerformInitializationByConstructor(InitType, 0, 0, 2262 Var->getLocation(), 2263 SourceRange(Var->getLocation(), 2264 Var->getLocation()), 2265 Var->getDeclName(), 2266 IK_Default); 2267 if (!Constructor) 2268 Var->setInvalidDecl(); 2269 } 2270 } 2271 2272#if 0 2273 // FIXME: Temporarily disabled because we are not properly parsing 2274 // linkage specifications on declarations, e.g., 2275 // 2276 // extern "C" const CGPoint CGPointerZero; 2277 // 2278 // C++ [dcl.init]p9: 2279 // 2280 // If no initializer is specified for an object, and the 2281 // object is of (possibly cv-qualified) non-POD class type (or 2282 // array thereof), the object shall be default-initialized; if 2283 // the object is of const-qualified type, the underlying class 2284 // type shall have a user-declared default 2285 // constructor. Otherwise, if no initializer is specified for 2286 // an object, the object and its subobjects, if any, have an 2287 // indeterminate initial value; if the object or any of its 2288 // subobjects are of const-qualified type, the program is 2289 // ill-formed. 2290 // 2291 // This isn't technically an error in C, so we don't diagnose it. 2292 // 2293 // FIXME: Actually perform the POD/user-defined default 2294 // constructor check. 2295 if (getLangOptions().CPlusPlus && 2296 Context.getCanonicalType(Type).isConstQualified() && 2297 Var->getStorageClass() != VarDecl::Extern) 2298 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2299 << Var->getName() 2300 << SourceRange(Var->getLocation(), Var->getLocation()); 2301#endif 2302 } 2303} 2304 2305/// The declarators are chained together backwards, reverse the list. 2306Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2307 // Often we have single declarators, handle them quickly. 2308 Decl *Group = static_cast<Decl*>(group); 2309 if (Group == 0) 2310 return 0; 2311 2312 Decl *NewGroup = 0; 2313 if (Group->getNextDeclarator() == 0) 2314 NewGroup = Group; 2315 else { // reverse the list. 2316 while (Group) { 2317 Decl *Next = Group->getNextDeclarator(); 2318 Group->setNextDeclarator(NewGroup); 2319 NewGroup = Group; 2320 Group = Next; 2321 } 2322 } 2323 // Perform semantic analysis that depends on having fully processed both 2324 // the declarator and initializer. 2325 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2326 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2327 if (!IDecl) 2328 continue; 2329 QualType T = IDecl->getType(); 2330 2331 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2332 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2333 if (IDecl->isBlockVarDecl() && 2334 IDecl->getStorageClass() != VarDecl::Extern) { 2335 if (!IDecl->isInvalidDecl() && 2336 RequireCompleteType(IDecl->getLocation(), T, 2337 diag::err_typecheck_decl_incomplete_type)) 2338 IDecl->setInvalidDecl(); 2339 } 2340 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2341 // object that has file scope without an initializer, and without a 2342 // storage-class specifier or with the storage-class specifier "static", 2343 // constitutes a tentative definition. Note: A tentative definition with 2344 // external linkage is valid (C99 6.2.2p5). 2345 if (isTentativeDefinition(IDecl)) { 2346 if (T->isIncompleteArrayType()) { 2347 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2348 // array to be completed. Don't issue a diagnostic. 2349 } else if (!IDecl->isInvalidDecl() && 2350 RequireCompleteType(IDecl->getLocation(), T, 2351 diag::err_typecheck_decl_incomplete_type)) 2352 // C99 6.9.2p3: If the declaration of an identifier for an object is 2353 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2354 // declared type shall not be an incomplete type. 2355 IDecl->setInvalidDecl(); 2356 } 2357 if (IDecl->isFileVarDecl()) 2358 CheckForFileScopedRedefinitions(S, IDecl); 2359 } 2360 return NewGroup; 2361} 2362 2363/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2364/// to introduce parameters into function prototype scope. 2365Sema::DeclTy * 2366Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2367 const DeclSpec &DS = D.getDeclSpec(); 2368 2369 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2370 VarDecl::StorageClass StorageClass = VarDecl::None; 2371 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2372 StorageClass = VarDecl::Register; 2373 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2374 Diag(DS.getStorageClassSpecLoc(), 2375 diag::err_invalid_storage_class_in_func_decl); 2376 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2377 } 2378 if (DS.isThreadSpecified()) { 2379 Diag(DS.getThreadSpecLoc(), 2380 diag::err_invalid_storage_class_in_func_decl); 2381 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2382 } 2383 2384 // Check that there are no default arguments inside the type of this 2385 // parameter (C++ only). 2386 if (getLangOptions().CPlusPlus) 2387 CheckExtraCXXDefaultArguments(D); 2388 2389 // In this context, we *do not* check D.getInvalidType(). If the declarator 2390 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2391 // though it will not reflect the user specified type. 2392 QualType parmDeclType = GetTypeForDeclarator(D, S); 2393 2394 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2395 2396 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2397 // Can this happen for params? We already checked that they don't conflict 2398 // among each other. Here they can only shadow globals, which is ok. 2399 IdentifierInfo *II = D.getIdentifier(); 2400 if (II) { 2401 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2402 if (PrevDecl->isTemplateParameter()) { 2403 // Maybe we will complain about the shadowed template parameter. 2404 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2405 // Just pretend that we didn't see the previous declaration. 2406 PrevDecl = 0; 2407 } else if (S->isDeclScope(PrevDecl)) { 2408 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2409 2410 // Recover by removing the name 2411 II = 0; 2412 D.SetIdentifier(0, D.getIdentifierLoc()); 2413 } 2414 } 2415 } 2416 2417 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2418 // Doing the promotion here has a win and a loss. The win is the type for 2419 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2420 // code generator). The loss is the orginal type isn't preserved. For example: 2421 // 2422 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2423 // int blockvardecl[5]; 2424 // sizeof(parmvardecl); // size == 4 2425 // sizeof(blockvardecl); // size == 20 2426 // } 2427 // 2428 // For expressions, all implicit conversions are captured using the 2429 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2430 // 2431 // FIXME: If a source translation tool needs to see the original type, then 2432 // we need to consider storing both types (in ParmVarDecl)... 2433 // 2434 if (parmDeclType->isArrayType()) { 2435 // int x[restrict 4] -> int *restrict 2436 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2437 } else if (parmDeclType->isFunctionType()) 2438 parmDeclType = Context.getPointerType(parmDeclType); 2439 2440 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2441 D.getIdentifierLoc(), II, 2442 parmDeclType, StorageClass, 2443 0); 2444 2445 if (D.getInvalidType()) 2446 New->setInvalidDecl(); 2447 2448 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2449 if (D.getCXXScopeSpec().isSet()) { 2450 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2451 << D.getCXXScopeSpec().getRange(); 2452 New->setInvalidDecl(); 2453 } 2454 // Parameter declarators cannot be interface types. All ObjC objects are 2455 // passed by reference. 2456 if (parmDeclType->isObjCInterfaceType()) { 2457 Diag(D.getIdentifierLoc(), diag::err_object_cannot_be_by_value) 2458 << "passed"; 2459 New->setInvalidDecl(); 2460 } 2461 2462 // Add the parameter declaration into this scope. 2463 S->AddDecl(New); 2464 if (II) 2465 IdResolver.AddDecl(New); 2466 2467 ProcessDeclAttributes(New, D); 2468 return New; 2469 2470} 2471 2472void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2473 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2474 "Not a function declarator!"); 2475 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2476 2477 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2478 // for a K&R function. 2479 if (!FTI.hasPrototype) { 2480 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2481 if (FTI.ArgInfo[i].Param == 0) { 2482 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2483 << FTI.ArgInfo[i].Ident; 2484 // Implicitly declare the argument as type 'int' for lack of a better 2485 // type. 2486 DeclSpec DS; 2487 const char* PrevSpec; // unused 2488 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2489 PrevSpec); 2490 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2491 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2492 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2493 } 2494 } 2495 } 2496} 2497 2498Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2499 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2500 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2501 "Not a function declarator!"); 2502 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2503 2504 if (FTI.hasPrototype) { 2505 // FIXME: Diagnose arguments without names in C. 2506 } 2507 2508 Scope *ParentScope = FnBodyScope->getParent(); 2509 2510 return ActOnStartOfFunctionDef(FnBodyScope, 2511 ActOnDeclarator(ParentScope, D, 0, 2512 /*IsFunctionDefinition=*/true)); 2513} 2514 2515Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2516 Decl *decl = static_cast<Decl*>(D); 2517 FunctionDecl *FD = cast<FunctionDecl>(decl); 2518 2519 ActiveScope = FnBodyScope; 2520 2521 // See if this is a redefinition. 2522 const FunctionDecl *Definition; 2523 if (FD->getBody(Definition)) { 2524 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2525 Diag(Definition->getLocation(), diag::note_previous_definition); 2526 } 2527 2528 // Builtin functions cannot be defined. 2529 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2530 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2531 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2532 FD->setInvalidDecl(); 2533 } 2534 } 2535 2536 // The return type of a function definition must be complete 2537 // (C99 6.9.1p3) 2538 if (FD->getResultType()->isIncompleteType() && 2539 !FD->getResultType()->isVoidType()) { 2540 Diag(FD->getLocation(), diag::err_func_def_incomplete_result) << FD; 2541 FD->setInvalidDecl(); 2542 } 2543 2544 PushDeclContext(FnBodyScope, FD); 2545 2546 // Check the validity of our function parameters 2547 CheckParmsForFunctionDef(FD); 2548 2549 // Introduce our parameters into the function scope 2550 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2551 ParmVarDecl *Param = FD->getParamDecl(p); 2552 Param->setOwningFunction(FD); 2553 2554 // If this has an identifier, add it to the scope stack. 2555 if (Param->getIdentifier()) 2556 PushOnScopeChains(Param, FnBodyScope); 2557 } 2558 2559 // Checking attributes of current function definition 2560 // dllimport attribute. 2561 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2562 // dllimport attribute cannot be applied to definition. 2563 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2564 Diag(FD->getLocation(), 2565 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2566 << "dllimport"; 2567 FD->setInvalidDecl(); 2568 return FD; 2569 } else { 2570 // If a symbol previously declared dllimport is later defined, the 2571 // attribute is ignored in subsequent references, and a warning is 2572 // emitted. 2573 Diag(FD->getLocation(), 2574 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2575 << FD->getNameAsCString() << "dllimport"; 2576 } 2577 } 2578 return FD; 2579} 2580 2581static bool StatementCreatesScope(Stmt* S) { 2582 bool result = false; 2583 if (DeclStmt* DS = dyn_cast<DeclStmt>(S)) { 2584 for (DeclStmt::decl_iterator i = DS->decl_begin(); 2585 i != DS->decl_end(); ++i) { 2586 if (VarDecl* D = dyn_cast<VarDecl>(*i)) { 2587 result |= D->getType()->isVariablyModifiedType(); 2588 result |= !!D->getAttr<CleanupAttr>(); 2589 } else if (TypedefDecl* D = dyn_cast<TypedefDecl>(*i)) { 2590 result |= D->getUnderlyingType()->isVariablyModifiedType(); 2591 } 2592 } 2593 } 2594 2595 return result; 2596} 2597 2598void Sema::RecursiveCalcLabelScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2599 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2600 std::vector<void*>& ScopeStack, 2601 Stmt* CurStmt, 2602 Stmt* ParentCompoundStmt) { 2603 for (Stmt::child_iterator i = CurStmt->child_begin(); 2604 i != CurStmt->child_end(); ++i) { 2605 if (!*i) continue; 2606 if (StatementCreatesScope(*i)) { 2607 ScopeStack.push_back(*i); 2608 PopScopeMap[*i] = ParentCompoundStmt; 2609 } else if (isa<LabelStmt>(CurStmt)) { 2610 LabelScopeMap[CurStmt] = ScopeStack.size() ? ScopeStack.back() : 0; 2611 } 2612 if (isa<DeclStmt>(*i)) continue; 2613 Stmt* CurCompound = isa<CompoundStmt>(*i) ? *i : ParentCompoundStmt; 2614 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, 2615 *i, CurCompound); 2616 } 2617 2618 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2619 ScopeStack.pop_back(); 2620 } 2621} 2622 2623void Sema::RecursiveCalcJumpScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2624 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2625 llvm::DenseMap<Stmt*, void*>& GotoScopeMap, 2626 std::vector<void*>& ScopeStack, 2627 Stmt* CurStmt) { 2628 for (Stmt::child_iterator i = CurStmt->child_begin(); 2629 i != CurStmt->child_end(); ++i) { 2630 if (!*i) continue; 2631 if (StatementCreatesScope(*i)) { 2632 ScopeStack.push_back(*i); 2633 } else if (GotoStmt* GS = dyn_cast<GotoStmt>(*i)) { 2634 void* LScope = LabelScopeMap[GS->getLabel()]; 2635 if (LScope) { 2636 bool foundScopeInStack = false; 2637 for (unsigned i = ScopeStack.size(); i > 0; --i) { 2638 if (LScope == ScopeStack[i-1]) { 2639 foundScopeInStack = true; 2640 break; 2641 } 2642 } 2643 if (!foundScopeInStack) { 2644 Diag(GS->getSourceRange().getBegin(), diag::err_goto_into_scope); 2645 } 2646 } 2647 } 2648 if (isa<DeclStmt>(*i)) continue; 2649 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, 2650 ScopeStack, *i); 2651 } 2652 2653 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2654 ScopeStack.pop_back(); 2655 } 2656} 2657 2658Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2659 Decl *dcl = static_cast<Decl *>(D); 2660 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2661 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2662 FD->setBody(Body); 2663 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2664 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2665 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2666 MD->setBody((Stmt*)Body); 2667 } else { 2668 Body->Destroy(Context); 2669 return 0; 2670 } 2671 PopDeclContext(); 2672 2673 // FIXME: Temporary hack to workaround nested C++ functions. For example: 2674 // class C2 { 2675 // void f() { 2676 // class LC1 { 2677 // int m() { return 1; } 2678 // }; 2679 // } 2680 // }; 2681 if (ActiveScope == 0) 2682 return D; 2683 2684 // Verify and clean out per-function state. 2685 2686 bool HaveLabels = !ActiveScope->LabelMap.empty(); 2687 // Check goto/label use. 2688 for (Scope::LabelMapTy::iterator I = ActiveScope->LabelMap.begin(), 2689 E = ActiveScope->LabelMap.end(); I != E; ++I) { 2690 // Verify that we have no forward references left. If so, there was a goto 2691 // or address of a label taken, but no definition of it. Label fwd 2692 // definitions are indicated with a null substmt. 2693 LabelStmt *L = static_cast<LabelStmt*>(I->second); 2694 if (L->getSubStmt() == 0) { 2695 // Emit error. 2696 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2697 2698 // At this point, we have gotos that use the bogus label. Stitch it into 2699 // the function body so that they aren't leaked and that the AST is well 2700 // formed. 2701 if (Body) { 2702#if 0 2703 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2704 // and the AST is malformed anyway. We should just blow away 'L'. 2705 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2706 cast<CompoundStmt>(Body)->push_back(L); 2707#else 2708 L->Destroy(Context); 2709#endif 2710 } else { 2711 // The whole function wasn't parsed correctly, just delete this. 2712 L->Destroy(Context); 2713 } 2714 } 2715 } 2716 // This reset is for both functions and methods. 2717 ActiveScope = 0; 2718 2719 if (!Body) return D; 2720 2721 if (HaveLabels) { 2722 llvm::DenseMap<Stmt*, void*> LabelScopeMap; 2723 llvm::DenseMap<void*, Stmt*> PopScopeMap; 2724 llvm::DenseMap<Stmt*, void*> GotoScopeMap; 2725 std::vector<void*> ScopeStack; 2726 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, Body, Body); 2727 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, ScopeStack, Body); 2728 } 2729 2730 return D; 2731} 2732 2733/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2734/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2735NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2736 IdentifierInfo &II, Scope *S) { 2737 // Before we produce a declaration for an implicitly defined 2738 // function, see whether there was a locally-scoped declaration of 2739 // this name as a function or variable. If so, use that 2740 // (non-visible) declaration, and complain about it. 2741 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2742 = LocallyScopedExternalDecls.find(&II); 2743 if (Pos != LocallyScopedExternalDecls.end()) { 2744 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 2745 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 2746 return Pos->second; 2747 } 2748 2749 // Extension in C99. Legal in C90, but warn about it. 2750 if (getLangOptions().C99) 2751 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2752 else 2753 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2754 2755 // FIXME: handle stuff like: 2756 // void foo() { extern float X(); } 2757 // void bar() { X(); } <-- implicit decl for X in another scope. 2758 2759 // Set a Declarator for the implicit definition: int foo(); 2760 const char *Dummy; 2761 DeclSpec DS; 2762 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2763 Error = Error; // Silence warning. 2764 assert(!Error && "Error setting up implicit decl!"); 2765 Declarator D(DS, Declarator::BlockContext); 2766 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 2767 0, 0, 0, Loc, D), 2768 SourceLocation()); 2769 D.SetIdentifier(&II, Loc); 2770 2771 // Insert this function into translation-unit scope. 2772 2773 DeclContext *PrevDC = CurContext; 2774 CurContext = Context.getTranslationUnitDecl(); 2775 2776 FunctionDecl *FD = 2777 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2778 FD->setImplicit(); 2779 2780 CurContext = PrevDC; 2781 2782 AddKnownFunctionAttributes(FD); 2783 2784 return FD; 2785} 2786 2787/// \brief Adds any function attributes that we know a priori based on 2788/// the declaration of this function. 2789/// 2790/// These attributes can apply both to implicitly-declared builtins 2791/// (like __builtin___printf_chk) or to library-declared functions 2792/// like NSLog or printf. 2793void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 2794 if (FD->isInvalidDecl()) 2795 return; 2796 2797 // If this is a built-in function, map its builtin attributes to 2798 // actual attributes. 2799 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2800 // Handle printf-formatting attributes. 2801 unsigned FormatIdx; 2802 bool HasVAListArg; 2803 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 2804 if (!FD->getAttr<FormatAttr>()) 2805 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 2806 FormatIdx + 2)); 2807 } 2808 2809 // Mark const if we don't care about errno and that is the only 2810 // thing preventing the function from being const. This allows 2811 // IRgen to use LLVM intrinsics for such functions. 2812 if (!getLangOptions().MathErrno && 2813 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 2814 if (!FD->getAttr<ConstAttr>()) 2815 FD->addAttr(::new (Context) ConstAttr()); 2816 } 2817 } 2818 2819 IdentifierInfo *Name = FD->getIdentifier(); 2820 if (!Name) 2821 return; 2822 if ((!getLangOptions().CPlusPlus && 2823 FD->getDeclContext()->isTranslationUnit()) || 2824 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 2825 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 2826 LinkageSpecDecl::lang_c)) { 2827 // Okay: this could be a libc/libm/Objective-C function we know 2828 // about. 2829 } else 2830 return; 2831 2832 unsigned KnownID; 2833 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 2834 if (KnownFunctionIDs[KnownID] == Name) 2835 break; 2836 2837 switch (KnownID) { 2838 case id_NSLog: 2839 case id_NSLogv: 2840 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 2841 // FIXME: We known better than our headers. 2842 const_cast<FormatAttr *>(Format)->setType("printf"); 2843 } else 2844 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 2845 break; 2846 2847 case id_asprintf: 2848 case id_vasprintf: 2849 if (!FD->getAttr<FormatAttr>()) 2850 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 2851 break; 2852 2853 default: 2854 // Unknown function or known function without any attributes to 2855 // add. Do nothing. 2856 break; 2857 } 2858} 2859 2860TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2861 Decl *LastDeclarator) { 2862 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2863 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2864 2865 // Scope manipulation handled by caller. 2866 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2867 D.getIdentifierLoc(), 2868 D.getIdentifier(), 2869 T); 2870 2871 if (TagType *TT = dyn_cast<TagType>(T)) { 2872 TagDecl *TD = TT->getDecl(); 2873 2874 // If the TagDecl that the TypedefDecl points to is an anonymous decl 2875 // keep track of the TypedefDecl. 2876 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 2877 TD->setTypedefForAnonDecl(NewTD); 2878 } 2879 2880 NewTD->setNextDeclarator(LastDeclarator); 2881 if (D.getInvalidType()) 2882 NewTD->setInvalidDecl(); 2883 return NewTD; 2884} 2885 2886/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2887/// former case, Name will be non-null. In the later case, Name will be null. 2888/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2889/// reference/declaration/definition of a tag. 2890Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2891 SourceLocation KWLoc, const CXXScopeSpec &SS, 2892 IdentifierInfo *Name, SourceLocation NameLoc, 2893 AttributeList *Attr) { 2894 // If this is not a definition, it must have a name. 2895 assert((Name != 0 || TK == TK_Definition) && 2896 "Nameless record must be a definition!"); 2897 2898 TagDecl::TagKind Kind; 2899 switch (TagSpec) { 2900 default: assert(0 && "Unknown tag type!"); 2901 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2902 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2903 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2904 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2905 } 2906 2907 DeclContext *SearchDC = CurContext; 2908 DeclContext *DC = CurContext; 2909 NamedDecl *PrevDecl = 0; 2910 2911 bool Invalid = false; 2912 2913 if (Name && SS.isNotEmpty()) { 2914 // We have a nested-name tag ('struct foo::bar'). 2915 2916 // Check for invalid 'foo::'. 2917 if (SS.isInvalid()) { 2918 Name = 0; 2919 goto CreateNewDecl; 2920 } 2921 2922 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2923 SearchDC = DC; 2924 // Look-up name inside 'foo::'. 2925 PrevDecl = dyn_cast_or_null<TagDecl>( 2926 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 2927 2928 // A tag 'foo::bar' must already exist. 2929 if (PrevDecl == 0) { 2930 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2931 Name = 0; 2932 goto CreateNewDecl; 2933 } 2934 } else if (Name) { 2935 // If this is a named struct, check to see if there was a previous forward 2936 // declaration or definition. 2937 // FIXME: We're looking into outer scopes here, even when we 2938 // shouldn't be. Doing so can result in ambiguities that we 2939 // shouldn't be diagnosing. 2940 LookupResult R = LookupName(S, Name, LookupTagName, 2941 /*RedeclarationOnly=*/(TK != TK_Reference)); 2942 if (R.isAmbiguous()) { 2943 DiagnoseAmbiguousLookup(R, Name, NameLoc); 2944 // FIXME: This is not best way to recover from case like: 2945 // 2946 // struct S s; 2947 // 2948 // causes needless err_ovl_no_viable_function_in_init latter. 2949 Name = 0; 2950 PrevDecl = 0; 2951 Invalid = true; 2952 } 2953 else 2954 PrevDecl = R; 2955 2956 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2957 // FIXME: This makes sure that we ignore the contexts associated 2958 // with C structs, unions, and enums when looking for a matching 2959 // tag declaration or definition. See the similar lookup tweak 2960 // in Sema::LookupName; is there a better way to deal with this? 2961 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2962 SearchDC = SearchDC->getParent(); 2963 } 2964 } 2965 2966 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2967 // Maybe we will complain about the shadowed template parameter. 2968 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2969 // Just pretend that we didn't see the previous declaration. 2970 PrevDecl = 0; 2971 } 2972 2973 if (PrevDecl) { 2974 // Check whether the previous declaration is usable. 2975 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 2976 2977 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2978 // If this is a use of a previous tag, or if the tag is already declared 2979 // in the same scope (so that the definition/declaration completes or 2980 // rementions the tag), reuse the decl. 2981 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2982 // Make sure that this wasn't declared as an enum and now used as a 2983 // struct or something similar. 2984 if (PrevTagDecl->getTagKind() != Kind) { 2985 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2986 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2987 // Recover by making this an anonymous redefinition. 2988 Name = 0; 2989 PrevDecl = 0; 2990 Invalid = true; 2991 } else { 2992 // If this is a use, just return the declaration we found. 2993 2994 // FIXME: In the future, return a variant or some other clue 2995 // for the consumer of this Decl to know it doesn't own it. 2996 // For our current ASTs this shouldn't be a problem, but will 2997 // need to be changed with DeclGroups. 2998 if (TK == TK_Reference) 2999 return PrevDecl; 3000 3001 // Diagnose attempts to redefine a tag. 3002 if (TK == TK_Definition) { 3003 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3004 Diag(NameLoc, diag::err_redefinition) << Name; 3005 Diag(Def->getLocation(), diag::note_previous_definition); 3006 // If this is a redefinition, recover by making this 3007 // struct be anonymous, which will make any later 3008 // references get the previous definition. 3009 Name = 0; 3010 PrevDecl = 0; 3011 Invalid = true; 3012 } else { 3013 // If the type is currently being defined, complain 3014 // about a nested redefinition. 3015 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3016 if (Tag->isBeingDefined()) { 3017 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3018 Diag(PrevTagDecl->getLocation(), 3019 diag::note_previous_definition); 3020 Name = 0; 3021 PrevDecl = 0; 3022 Invalid = true; 3023 } 3024 } 3025 3026 // Okay, this is definition of a previously declared or referenced 3027 // tag PrevDecl. We're going to create a new Decl for it. 3028 } 3029 } 3030 // If we get here we have (another) forward declaration or we 3031 // have a definition. Just create a new decl. 3032 } else { 3033 // If we get here, this is a definition of a new tag type in a nested 3034 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3035 // new decl/type. We set PrevDecl to NULL so that the entities 3036 // have distinct types. 3037 PrevDecl = 0; 3038 } 3039 // If we get here, we're going to create a new Decl. If PrevDecl 3040 // is non-NULL, it's a definition of the tag declared by 3041 // PrevDecl. If it's NULL, we have a new definition. 3042 } else { 3043 // PrevDecl is a namespace, template, or anything else 3044 // that lives in the IDNS_Tag identifier namespace. 3045 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3046 // The tag name clashes with a namespace name, issue an error and 3047 // recover by making this tag be anonymous. 3048 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3049 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3050 Name = 0; 3051 PrevDecl = 0; 3052 Invalid = true; 3053 } else { 3054 // The existing declaration isn't relevant to us; we're in a 3055 // new scope, so clear out the previous declaration. 3056 PrevDecl = 0; 3057 } 3058 } 3059 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3060 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3061 // C.scope.pdecl]p5: 3062 // -- for an elaborated-type-specifier of the form 3063 // 3064 // class-key identifier 3065 // 3066 // if the elaborated-type-specifier is used in the 3067 // decl-specifier-seq or parameter-declaration-clause of a 3068 // function defined in namespace scope, the identifier is 3069 // declared as a class-name in the namespace that contains 3070 // the declaration; otherwise, except as a friend 3071 // declaration, the identifier is declared in the smallest 3072 // non-class, non-function-prototype scope that contains the 3073 // declaration. 3074 // 3075 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3076 // C structs and unions. 3077 // 3078 // GNU C also supports this behavior as part of its incomplete 3079 // enum types extension, while GNU C++ does not. 3080 // 3081 // Find the context where we'll be declaring the tag. 3082 // FIXME: We would like to maintain the current DeclContext as the 3083 // lexical context, 3084 while (SearchDC->isRecord()) 3085 SearchDC = SearchDC->getParent(); 3086 3087 // Find the scope where we'll be declaring the tag. 3088 while (S->isClassScope() || 3089 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3090 ((S->getFlags() & Scope::DeclScope) == 0) || 3091 (S->getEntity() && 3092 ((DeclContext *)S->getEntity())->isTransparentContext())) 3093 S = S->getParent(); 3094 } 3095 3096CreateNewDecl: 3097 3098 // If there is an identifier, use the location of the identifier as the 3099 // location of the decl, otherwise use the location of the struct/union 3100 // keyword. 3101 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3102 3103 // Otherwise, create a new declaration. If there is a previous 3104 // declaration of the same entity, the two will be linked via 3105 // PrevDecl. 3106 TagDecl *New; 3107 3108 if (Kind == TagDecl::TK_enum) { 3109 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3110 // enum X { A, B, C } D; D should chain to X. 3111 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3112 cast_or_null<EnumDecl>(PrevDecl)); 3113 // If this is an undefined enum, warn. 3114 if (TK != TK_Definition && !Invalid) { 3115 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3116 : diag::ext_forward_ref_enum; 3117 Diag(Loc, DK); 3118 } 3119 } else { 3120 // struct/union/class 3121 3122 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3123 // struct X { int A; } D; D should chain to X. 3124 if (getLangOptions().CPlusPlus) 3125 // FIXME: Look for a way to use RecordDecl for simple structs. 3126 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3127 cast_or_null<CXXRecordDecl>(PrevDecl)); 3128 else 3129 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3130 cast_or_null<RecordDecl>(PrevDecl)); 3131 } 3132 3133 if (Kind != TagDecl::TK_enum) { 3134 // Handle #pragma pack: if the #pragma pack stack has non-default 3135 // alignment, make up a packed attribute for this decl. These 3136 // attributes are checked when the ASTContext lays out the 3137 // structure. 3138 // 3139 // It is important for implementing the correct semantics that this 3140 // happen here (in act on tag decl). The #pragma pack stack is 3141 // maintained as a result of parser callbacks which can occur at 3142 // many points during the parsing of a struct declaration (because 3143 // the #pragma tokens are effectively skipped over during the 3144 // parsing of the struct). 3145 if (unsigned Alignment = getPragmaPackAlignment()) 3146 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3147 } 3148 3149 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3150 // C++ [dcl.typedef]p3: 3151 // [...] Similarly, in a given scope, a class or enumeration 3152 // shall not be declared with the same name as a typedef-name 3153 // that is declared in that scope and refers to a type other 3154 // than the class or enumeration itself. 3155 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3156 TypedefDecl *PrevTypedef = 0; 3157 if (Lookup.getKind() == LookupResult::Found) 3158 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3159 3160 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3161 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3162 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3163 Diag(Loc, diag::err_tag_definition_of_typedef) 3164 << Context.getTypeDeclType(New) 3165 << PrevTypedef->getUnderlyingType(); 3166 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3167 Invalid = true; 3168 } 3169 } 3170 3171 if (Invalid) 3172 New->setInvalidDecl(); 3173 3174 if (Attr) 3175 ProcessDeclAttributeList(New, Attr); 3176 3177 // If we're declaring or defining a tag in function prototype scope 3178 // in C, note that this type can only be used within the function. 3179 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3180 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3181 3182 // Set the lexical context. If the tag has a C++ scope specifier, the 3183 // lexical context will be different from the semantic context. 3184 New->setLexicalDeclContext(CurContext); 3185 3186 if (TK == TK_Definition) 3187 New->startDefinition(); 3188 3189 // If this has an identifier, add it to the scope stack. 3190 if (Name) { 3191 S = getNonFieldDeclScope(S); 3192 PushOnScopeChains(New, S); 3193 } else { 3194 CurContext->addDecl(New); 3195 } 3196 3197 return New; 3198} 3199 3200void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3201 AdjustDeclIfTemplate(TagD); 3202 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3203 3204 // Enter the tag context. 3205 PushDeclContext(S, Tag); 3206 3207 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3208 FieldCollector->StartClass(); 3209 3210 if (Record->getIdentifier()) { 3211 // C++ [class]p2: 3212 // [...] The class-name is also inserted into the scope of the 3213 // class itself; this is known as the injected-class-name. For 3214 // purposes of access checking, the injected-class-name is treated 3215 // as if it were a public member name. 3216 RecordDecl *InjectedClassName 3217 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3218 CurContext, Record->getLocation(), 3219 Record->getIdentifier(), Record); 3220 InjectedClassName->setImplicit(); 3221 PushOnScopeChains(InjectedClassName, S); 3222 } 3223 } 3224} 3225 3226void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3227 AdjustDeclIfTemplate(TagD); 3228 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3229 3230 if (isa<CXXRecordDecl>(Tag)) 3231 FieldCollector->FinishClass(); 3232 3233 // Exit this scope of this tag's definition. 3234 PopDeclContext(); 3235 3236 // Notify the consumer that we've defined a tag. 3237 Consumer.HandleTagDeclDefinition(Tag); 3238} 3239 3240bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3241 QualType FieldTy, const Expr *BitWidth) { 3242 // C99 6.7.2.1p4 - verify the field type. 3243 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3244 if (!FieldTy->isIntegralType()) { 3245 // Handle incomplete types with specific error. 3246 if (FieldTy->isIncompleteType()) 3247 return Diag(FieldLoc, diag::err_field_incomplete) 3248 << FieldTy << BitWidth->getSourceRange(); 3249 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3250 << FieldName << BitWidth->getSourceRange(); 3251 } 3252 3253 llvm::APSInt Value; 3254 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3255 return true; 3256 3257 // Zero-width bitfield is ok for anonymous field. 3258 if (Value == 0 && FieldName) 3259 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3260 3261 if (Value.isNegative()) 3262 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3263 3264 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3265 // FIXME: We won't need the 0 size once we check that the field type is valid. 3266 if (TypeSize && Value.getZExtValue() > TypeSize) 3267 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3268 << FieldName << (unsigned)TypeSize; 3269 3270 return false; 3271} 3272 3273/// ActOnField - Each field of a struct/union/class is passed into this in order 3274/// to create a FieldDecl object for it. 3275Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3276 SourceLocation DeclStart, 3277 Declarator &D, ExprTy *BitfieldWidth) { 3278 return HandleField(S, static_cast<RecordDecl*>(TagD), DeclStart, D, 3279 static_cast<Expr*>(BitfieldWidth)); 3280} 3281 3282/// HandleField - Analyze a field of a C struct or a C++ data member. 3283/// 3284FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3285 SourceLocation DeclStart, 3286 Declarator &D, Expr *BitWidth) { 3287 IdentifierInfo *II = D.getIdentifier(); 3288 SourceLocation Loc = DeclStart; 3289 if (II) Loc = D.getIdentifierLoc(); 3290 3291 QualType T = GetTypeForDeclarator(D, S); 3292 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3293 bool InvalidDecl = false; 3294 3295 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3296 // than a variably modified type. 3297 if (T->isVariablyModifiedType()) { 3298 bool SizeIsNegative; 3299 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3300 SizeIsNegative); 3301 if (!FixedTy.isNull()) { 3302 Diag(Loc, diag::warn_illegal_constant_array_size); 3303 T = FixedTy; 3304 } else { 3305 if (SizeIsNegative) 3306 Diag(Loc, diag::err_typecheck_negative_array_size); 3307 else 3308 Diag(Loc, diag::err_typecheck_field_variable_size); 3309 T = Context.IntTy; 3310 InvalidDecl = true; 3311 } 3312 } 3313 3314 if (BitWidth) { 3315 if (VerifyBitField(Loc, II, T, BitWidth)) { 3316 InvalidDecl = true; 3317 DeleteExpr(BitWidth); 3318 BitWidth = 0; 3319 } 3320 } else { 3321 // Not a bitfield. 3322 3323 // validate II. 3324 3325 } 3326 3327 FieldDecl *NewFD = FieldDecl::Create(Context, Record, 3328 Loc, II, T, BitWidth, 3329 D.getDeclSpec().getStorageClassSpec() == 3330 DeclSpec::SCS_mutable); 3331 3332 if (II) { 3333 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3334 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3335 && !isa<TagDecl>(PrevDecl)) { 3336 Diag(Loc, diag::err_duplicate_member) << II; 3337 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3338 NewFD->setInvalidDecl(); 3339 Record->setInvalidDecl(); 3340 } 3341 } 3342 3343 if (getLangOptions().CPlusPlus) { 3344 CheckExtraCXXDefaultArguments(D); 3345 if (!T->isPODType()) 3346 cast<CXXRecordDecl>(Record)->setPOD(false); 3347 } 3348 3349 ProcessDeclAttributes(NewFD, D); 3350 if (T.isObjCGCWeak()) 3351 Diag(Loc, diag::warn_attribute_weak_on_field); 3352 3353 if (D.getInvalidType() || InvalidDecl) 3354 NewFD->setInvalidDecl(); 3355 3356 if (II) { 3357 PushOnScopeChains(NewFD, S); 3358 } else 3359 Record->addDecl(NewFD); 3360 3361 return NewFD; 3362} 3363 3364/// TranslateIvarVisibility - Translate visibility from a token ID to an 3365/// AST enum value. 3366static ObjCIvarDecl::AccessControl 3367TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3368 switch (ivarVisibility) { 3369 default: assert(0 && "Unknown visitibility kind"); 3370 case tok::objc_private: return ObjCIvarDecl::Private; 3371 case tok::objc_public: return ObjCIvarDecl::Public; 3372 case tok::objc_protected: return ObjCIvarDecl::Protected; 3373 case tok::objc_package: return ObjCIvarDecl::Package; 3374 } 3375} 3376 3377/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3378/// in order to create an IvarDecl object for it. 3379Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3380 SourceLocation DeclStart, 3381 Declarator &D, ExprTy *BitfieldWidth, 3382 tok::ObjCKeywordKind Visibility) { 3383 3384 IdentifierInfo *II = D.getIdentifier(); 3385 Expr *BitWidth = (Expr*)BitfieldWidth; 3386 SourceLocation Loc = DeclStart; 3387 if (II) Loc = D.getIdentifierLoc(); 3388 3389 // FIXME: Unnamed fields can be handled in various different ways, for 3390 // example, unnamed unions inject all members into the struct namespace! 3391 3392 QualType T = GetTypeForDeclarator(D, S); 3393 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3394 bool InvalidDecl = false; 3395 3396 if (BitWidth) { 3397 // 6.7.2.1p3, 6.7.2.1p4 3398 if (VerifyBitField(Loc, II, T, BitWidth)) { 3399 InvalidDecl = true; 3400 DeleteExpr(BitWidth); 3401 BitWidth = 0; 3402 } 3403 } else { 3404 // Not a bitfield. 3405 3406 // validate II. 3407 3408 } 3409 3410 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3411 // than a variably modified type. 3412 if (T->isVariablyModifiedType()) { 3413 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3414 InvalidDecl = true; 3415 } 3416 3417 // Get the visibility (access control) for this ivar. 3418 ObjCIvarDecl::AccessControl ac = 3419 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3420 : ObjCIvarDecl::None; 3421 3422 // Construct the decl. 3423 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3424 (Expr *)BitfieldWidth); 3425 3426 if (II) { 3427 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3428 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3429 && !isa<TagDecl>(PrevDecl)) { 3430 Diag(Loc, diag::err_duplicate_member) << II; 3431 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3432 NewID->setInvalidDecl(); 3433 } 3434 } 3435 3436 // Process attributes attached to the ivar. 3437 ProcessDeclAttributes(NewID, D); 3438 3439 if (D.getInvalidType() || InvalidDecl) 3440 NewID->setInvalidDecl(); 3441 3442 if (II) { 3443 // FIXME: When interfaces are DeclContexts, we'll need to add 3444 // these to the interface. 3445 S->AddDecl(NewID); 3446 IdResolver.AddDecl(NewID); 3447 } 3448 3449 return NewID; 3450} 3451 3452void Sema::ActOnFields(Scope* S, 3453 SourceLocation RecLoc, DeclTy *RecDecl, 3454 DeclTy **Fields, unsigned NumFields, 3455 SourceLocation LBrac, SourceLocation RBrac, 3456 AttributeList *Attr) { 3457 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3458 assert(EnclosingDecl && "missing record or interface decl"); 3459 3460 // If the decl this is being inserted into is invalid, then it may be a 3461 // redeclaration or some other bogus case. Don't try to add fields to it. 3462 if (EnclosingDecl->isInvalidDecl()) { 3463 // FIXME: Deallocate fields? 3464 return; 3465 } 3466 3467 3468 // Verify that all the fields are okay. 3469 unsigned NumNamedMembers = 0; 3470 llvm::SmallVector<FieldDecl*, 32> RecFields; 3471 3472 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3473 for (unsigned i = 0; i != NumFields; ++i) { 3474 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3475 assert(FD && "missing field decl"); 3476 3477 // Get the type for the field. 3478 Type *FDTy = FD->getType().getTypePtr(); 3479 3480 if (!FD->isAnonymousStructOrUnion()) { 3481 // Remember all fields written by the user. 3482 RecFields.push_back(FD); 3483 } 3484 3485 // If the field is already invalid for some reason, don't emit more 3486 // diagnostics about it. 3487 if (FD->isInvalidDecl()) 3488 continue; 3489 3490 // C99 6.7.2.1p2 - A field may not be a function type. 3491 if (FDTy->isFunctionType()) { 3492 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3493 << FD->getDeclName(); 3494 FD->setInvalidDecl(); 3495 EnclosingDecl->setInvalidDecl(); 3496 continue; 3497 } 3498 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3499 if (FDTy->isIncompleteType()) { 3500 if (!Record) { // Incomplete ivar type is always an error. 3501 RequireCompleteType(FD->getLocation(), FD->getType(), 3502 diag::err_field_incomplete); 3503 FD->setInvalidDecl(); 3504 EnclosingDecl->setInvalidDecl(); 3505 continue; 3506 } 3507 if (i != NumFields-1 || // ... that the last member ... 3508 !Record->isStruct() || // ... of a structure ... 3509 !FDTy->isArrayType()) { //... may have incomplete array type. 3510 RequireCompleteType(FD->getLocation(), FD->getType(), 3511 diag::err_field_incomplete); 3512 FD->setInvalidDecl(); 3513 EnclosingDecl->setInvalidDecl(); 3514 continue; 3515 } 3516 if (NumNamedMembers < 1) { //... must have more than named member ... 3517 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3518 << FD->getDeclName(); 3519 FD->setInvalidDecl(); 3520 EnclosingDecl->setInvalidDecl(); 3521 continue; 3522 } 3523 // Okay, we have a legal flexible array member at the end of the struct. 3524 if (Record) 3525 Record->setHasFlexibleArrayMember(true); 3526 } 3527 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3528 /// field of another structure or the element of an array. 3529 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3530 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3531 // If this is a member of a union, then entire union becomes "flexible". 3532 if (Record && Record->isUnion()) { 3533 Record->setHasFlexibleArrayMember(true); 3534 } else { 3535 // If this is a struct/class and this is not the last element, reject 3536 // it. Note that GCC supports variable sized arrays in the middle of 3537 // structures. 3538 if (i != NumFields-1) 3539 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3540 << FD->getDeclName(); 3541 else { 3542 // We support flexible arrays at the end of structs in 3543 // other structs as an extension. 3544 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3545 << FD->getDeclName(); 3546 if (Record) 3547 Record->setHasFlexibleArrayMember(true); 3548 } 3549 } 3550 } 3551 } 3552 /// A field cannot be an Objective-c object 3553 if (FDTy->isObjCInterfaceType()) { 3554 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3555 FD->setInvalidDecl(); 3556 EnclosingDecl->setInvalidDecl(); 3557 continue; 3558 } 3559 // Keep track of the number of named members. 3560 if (FD->getIdentifier()) 3561 ++NumNamedMembers; 3562 } 3563 3564 // Okay, we successfully defined 'Record'. 3565 if (Record) { 3566 Record->completeDefinition(Context); 3567 } else { 3568 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3569 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3570 ID->setIVarList(ClsFields, RecFields.size(), Context); 3571 ID->setLocEnd(RBrac); 3572 3573 // Must enforce the rule that ivars in the base classes may not be 3574 // duplicates. 3575 if (ID->getSuperClass()) { 3576 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3577 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3578 ObjCIvarDecl* Ivar = (*IVI); 3579 IdentifierInfo *II = Ivar->getIdentifier(); 3580 ObjCIvarDecl* prevIvar = 3581 ID->getSuperClass()->lookupInstanceVariable(II); 3582 if (prevIvar) { 3583 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3584 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3585 } 3586 } 3587 } 3588 } else if (ObjCImplementationDecl *IMPDecl = 3589 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3590 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3591 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3592 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3593 } 3594 } 3595 3596 if (Attr) 3597 ProcessDeclAttributeList(Record, Attr); 3598} 3599 3600Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3601 DeclTy *lastEnumConst, 3602 SourceLocation IdLoc, IdentifierInfo *Id, 3603 SourceLocation EqualLoc, ExprTy *val) { 3604 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3605 EnumConstantDecl *LastEnumConst = 3606 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3607 Expr *Val = static_cast<Expr*>(val); 3608 3609 // The scope passed in may not be a decl scope. Zip up the scope tree until 3610 // we find one that is. 3611 S = getNonFieldDeclScope(S); 3612 3613 // Verify that there isn't already something declared with this name in this 3614 // scope. 3615 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3616 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3617 // Maybe we will complain about the shadowed template parameter. 3618 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3619 // Just pretend that we didn't see the previous declaration. 3620 PrevDecl = 0; 3621 } 3622 3623 if (PrevDecl) { 3624 // When in C++, we may get a TagDecl with the same name; in this case the 3625 // enum constant will 'hide' the tag. 3626 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3627 "Received TagDecl when not in C++!"); 3628 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3629 if (isa<EnumConstantDecl>(PrevDecl)) 3630 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3631 else 3632 Diag(IdLoc, diag::err_redefinition) << Id; 3633 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3634 if (Val) Val->Destroy(Context); 3635 return 0; 3636 } 3637 } 3638 3639 llvm::APSInt EnumVal(32); 3640 QualType EltTy; 3641 if (Val) { 3642 // Make sure to promote the operand type to int. 3643 UsualUnaryConversions(Val); 3644 3645 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3646 SourceLocation ExpLoc; 3647 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3648 Val->Destroy(Context); 3649 Val = 0; // Just forget about it. 3650 } else { 3651 EltTy = Val->getType(); 3652 } 3653 } 3654 3655 if (!Val) { 3656 if (LastEnumConst) { 3657 // Assign the last value + 1. 3658 EnumVal = LastEnumConst->getInitVal(); 3659 ++EnumVal; 3660 3661 // Check for overflow on increment. 3662 if (EnumVal < LastEnumConst->getInitVal()) 3663 Diag(IdLoc, diag::warn_enum_value_overflow); 3664 3665 EltTy = LastEnumConst->getType(); 3666 } else { 3667 // First value, set to zero. 3668 EltTy = Context.IntTy; 3669 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3670 } 3671 } 3672 3673 EnumConstantDecl *New = 3674 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3675 Val, EnumVal); 3676 3677 // Register this decl in the current scope stack. 3678 PushOnScopeChains(New, S); 3679 3680 return New; 3681} 3682 3683// FIXME: For consistency with ActOnFields(), we should have the parser 3684// pass in the source location for the left/right braces. 3685void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3686 DeclTy **Elements, unsigned NumElements) { 3687 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3688 QualType EnumType = Context.getTypeDeclType(Enum); 3689 3690 // TODO: If the result value doesn't fit in an int, it must be a long or long 3691 // long value. ISO C does not support this, but GCC does as an extension, 3692 // emit a warning. 3693 unsigned IntWidth = Context.Target.getIntWidth(); 3694 3695 // Verify that all the values are okay, compute the size of the values, and 3696 // reverse the list. 3697 unsigned NumNegativeBits = 0; 3698 unsigned NumPositiveBits = 0; 3699 3700 // Keep track of whether all elements have type int. 3701 bool AllElementsInt = true; 3702 3703 for (unsigned i = 0; i != NumElements; ++i) { 3704 EnumConstantDecl *ECD = 3705 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3706 if (!ECD) continue; // Already issued a diagnostic. 3707 3708 // If the enum value doesn't fit in an int, emit an extension warning. 3709 const llvm::APSInt &InitVal = ECD->getInitVal(); 3710 assert(InitVal.getBitWidth() >= IntWidth && 3711 "Should have promoted value to int"); 3712 if (InitVal.getBitWidth() > IntWidth) { 3713 llvm::APSInt V(InitVal); 3714 V.trunc(IntWidth); 3715 V.extend(InitVal.getBitWidth()); 3716 if (V != InitVal) 3717 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3718 << InitVal.toString(10); 3719 } 3720 3721 // Keep track of the size of positive and negative values. 3722 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3723 NumPositiveBits = std::max(NumPositiveBits, 3724 (unsigned)InitVal.getActiveBits()); 3725 else 3726 NumNegativeBits = std::max(NumNegativeBits, 3727 (unsigned)InitVal.getMinSignedBits()); 3728 3729 // Keep track of whether every enum element has type int (very commmon). 3730 if (AllElementsInt) 3731 AllElementsInt = ECD->getType() == Context.IntTy; 3732 } 3733 3734 // Figure out the type that should be used for this enum. 3735 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3736 QualType BestType; 3737 unsigned BestWidth; 3738 3739 if (NumNegativeBits) { 3740 // If there is a negative value, figure out the smallest integer type (of 3741 // int/long/longlong) that fits. 3742 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3743 BestType = Context.IntTy; 3744 BestWidth = IntWidth; 3745 } else { 3746 BestWidth = Context.Target.getLongWidth(); 3747 3748 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3749 BestType = Context.LongTy; 3750 else { 3751 BestWidth = Context.Target.getLongLongWidth(); 3752 3753 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3754 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3755 BestType = Context.LongLongTy; 3756 } 3757 } 3758 } else { 3759 // If there is no negative value, figure out which of uint, ulong, ulonglong 3760 // fits. 3761 if (NumPositiveBits <= IntWidth) { 3762 BestType = Context.UnsignedIntTy; 3763 BestWidth = IntWidth; 3764 } else if (NumPositiveBits <= 3765 (BestWidth = Context.Target.getLongWidth())) { 3766 BestType = Context.UnsignedLongTy; 3767 } else { 3768 BestWidth = Context.Target.getLongLongWidth(); 3769 assert(NumPositiveBits <= BestWidth && 3770 "How could an initializer get larger than ULL?"); 3771 BestType = Context.UnsignedLongLongTy; 3772 } 3773 } 3774 3775 // Loop over all of the enumerator constants, changing their types to match 3776 // the type of the enum if needed. 3777 for (unsigned i = 0; i != NumElements; ++i) { 3778 EnumConstantDecl *ECD = 3779 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3780 if (!ECD) continue; // Already issued a diagnostic. 3781 3782 // Standard C says the enumerators have int type, but we allow, as an 3783 // extension, the enumerators to be larger than int size. If each 3784 // enumerator value fits in an int, type it as an int, otherwise type it the 3785 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3786 // that X has type 'int', not 'unsigned'. 3787 if (ECD->getType() == Context.IntTy) { 3788 // Make sure the init value is signed. 3789 llvm::APSInt IV = ECD->getInitVal(); 3790 IV.setIsSigned(true); 3791 ECD->setInitVal(IV); 3792 3793 if (getLangOptions().CPlusPlus) 3794 // C++ [dcl.enum]p4: Following the closing brace of an 3795 // enum-specifier, each enumerator has the type of its 3796 // enumeration. 3797 ECD->setType(EnumType); 3798 continue; // Already int type. 3799 } 3800 3801 // Determine whether the value fits into an int. 3802 llvm::APSInt InitVal = ECD->getInitVal(); 3803 bool FitsInInt; 3804 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3805 FitsInInt = InitVal.getActiveBits() < IntWidth; 3806 else 3807 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3808 3809 // If it fits into an integer type, force it. Otherwise force it to match 3810 // the enum decl type. 3811 QualType NewTy; 3812 unsigned NewWidth; 3813 bool NewSign; 3814 if (FitsInInt) { 3815 NewTy = Context.IntTy; 3816 NewWidth = IntWidth; 3817 NewSign = true; 3818 } else if (ECD->getType() == BestType) { 3819 // Already the right type! 3820 if (getLangOptions().CPlusPlus) 3821 // C++ [dcl.enum]p4: Following the closing brace of an 3822 // enum-specifier, each enumerator has the type of its 3823 // enumeration. 3824 ECD->setType(EnumType); 3825 continue; 3826 } else { 3827 NewTy = BestType; 3828 NewWidth = BestWidth; 3829 NewSign = BestType->isSignedIntegerType(); 3830 } 3831 3832 // Adjust the APSInt value. 3833 InitVal.extOrTrunc(NewWidth); 3834 InitVal.setIsSigned(NewSign); 3835 ECD->setInitVal(InitVal); 3836 3837 // Adjust the Expr initializer and type. 3838 if (ECD->getInitExpr()) 3839 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3840 /*isLvalue=*/false)); 3841 if (getLangOptions().CPlusPlus) 3842 // C++ [dcl.enum]p4: Following the closing brace of an 3843 // enum-specifier, each enumerator has the type of its 3844 // enumeration. 3845 ECD->setType(EnumType); 3846 else 3847 ECD->setType(NewTy); 3848 } 3849 3850 Enum->completeDefinition(Context, BestType); 3851} 3852 3853Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3854 ExprArg expr) { 3855 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3856 3857 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3858} 3859 3860