SemaDecl.cpp revision 4fdf1faedbca40787fd277a6fbd5061fd69b2708
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/// MergeVarDecl - We just parsed a variable 'New' which has the same name 780/// and scope as a previous declaration 'Old'. Figure out how to resolve this 781/// situation, merging decls or emitting diagnostics as appropriate. 782/// 783/// Tentative definition rules (C99 6.9.2p2) are checked by 784/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 785/// definitions here, since the initializer hasn't been attached. 786/// 787bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 788 // Verify the old decl was also a variable. 789 VarDecl *Old = dyn_cast<VarDecl>(OldD); 790 if (!Old) { 791 Diag(New->getLocation(), diag::err_redefinition_different_kind) 792 << New->getDeclName(); 793 Diag(OldD->getLocation(), diag::note_previous_definition); 794 return true; 795 } 796 797 MergeAttributes(New, Old, Context); 798 799 // Merge the types 800 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 801 if (MergedT.isNull()) { 802 Diag(New->getLocation(), diag::err_redefinition_different_type) 803 << New->getDeclName(); 804 Diag(Old->getLocation(), diag::note_previous_definition); 805 return true; 806 } 807 New->setType(MergedT); 808 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 809 if (New->getStorageClass() == VarDecl::Static && 810 (Old->getStorageClass() == VarDecl::None || 811 Old->getStorageClass() == VarDecl::Extern)) { 812 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 813 Diag(Old->getLocation(), diag::note_previous_definition); 814 return true; 815 } 816 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 817 if (New->getStorageClass() != VarDecl::Static && 818 Old->getStorageClass() == VarDecl::Static) { 819 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 820 Diag(Old->getLocation(), diag::note_previous_definition); 821 return true; 822 } 823 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 824 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 825 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 826 Diag(Old->getLocation(), diag::note_previous_definition); 827 return true; 828 } 829 830 // Keep a chain of previous declarations. 831 New->setPreviousDeclaration(Old); 832 833 return false; 834} 835 836/// CheckParmsForFunctionDef - Check that the parameters of the given 837/// function are appropriate for the definition of a function. This 838/// takes care of any checks that cannot be performed on the 839/// declaration itself, e.g., that the types of each of the function 840/// parameters are complete. 841bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 842 bool HasInvalidParm = false; 843 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 844 ParmVarDecl *Param = FD->getParamDecl(p); 845 846 // C99 6.7.5.3p4: the parameters in a parameter type list in a 847 // function declarator that is part of a function definition of 848 // that function shall not have incomplete type. 849 if (!Param->isInvalidDecl() && 850 RequireCompleteType(Param->getLocation(), Param->getType(), 851 diag::err_typecheck_decl_incomplete_type)) { 852 Param->setInvalidDecl(); 853 HasInvalidParm = true; 854 } 855 856 // C99 6.9.1p5: If the declarator includes a parameter type list, the 857 // declaration of each parameter shall include an identifier. 858 if (Param->getIdentifier() == 0 && 859 !Param->isImplicit() && 860 !getLangOptions().CPlusPlus) 861 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 862 } 863 864 return HasInvalidParm; 865} 866 867/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 868/// no declarator (e.g. "struct foo;") is parsed. 869Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 870 TagDecl *Tag = 0; 871 if (DS.getTypeSpecType() == DeclSpec::TST_class || 872 DS.getTypeSpecType() == DeclSpec::TST_struct || 873 DS.getTypeSpecType() == DeclSpec::TST_union || 874 DS.getTypeSpecType() == DeclSpec::TST_enum) 875 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 876 877 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 878 if (!Record->getDeclName() && Record->isDefinition() && 879 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 880 if (getLangOptions().CPlusPlus || 881 Record->getDeclContext()->isRecord()) 882 return BuildAnonymousStructOrUnion(S, DS, Record); 883 884 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 885 << DS.getSourceRange(); 886 } 887 888 // Microsoft allows unnamed struct/union fields. Don't complain 889 // about them. 890 // FIXME: Should we support Microsoft's extensions in this area? 891 if (Record->getDeclName() && getLangOptions().Microsoft) 892 return Tag; 893 } 894 895 if (!DS.isMissingDeclaratorOk() && 896 DS.getTypeSpecType() != DeclSpec::TST_error) { 897 // Warn about typedefs of enums without names, since this is an 898 // extension in both Microsoft an GNU. 899 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 900 Tag && isa<EnumDecl>(Tag)) { 901 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 902 << DS.getSourceRange(); 903 return Tag; 904 } 905 906 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 907 << DS.getSourceRange(); 908 return 0; 909 } 910 911 return Tag; 912} 913 914/// InjectAnonymousStructOrUnionMembers - Inject the members of the 915/// anonymous struct or union AnonRecord into the owning context Owner 916/// and scope S. This routine will be invoked just after we realize 917/// that an unnamed union or struct is actually an anonymous union or 918/// struct, e.g., 919/// 920/// @code 921/// union { 922/// int i; 923/// float f; 924/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 925/// // f into the surrounding scope.x 926/// @endcode 927/// 928/// This routine is recursive, injecting the names of nested anonymous 929/// structs/unions into the owning context and scope as well. 930bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 931 RecordDecl *AnonRecord) { 932 bool Invalid = false; 933 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 934 FEnd = AnonRecord->field_end(); 935 F != FEnd; ++F) { 936 if ((*F)->getDeclName()) { 937 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 938 LookupOrdinaryName, true); 939 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 940 // C++ [class.union]p2: 941 // The names of the members of an anonymous union shall be 942 // distinct from the names of any other entity in the 943 // scope in which the anonymous union is declared. 944 unsigned diagKind 945 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 946 : diag::err_anonymous_struct_member_redecl; 947 Diag((*F)->getLocation(), diagKind) 948 << (*F)->getDeclName(); 949 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 950 Invalid = true; 951 } else { 952 // C++ [class.union]p2: 953 // For the purpose of name lookup, after the anonymous union 954 // definition, the members of the anonymous union are 955 // considered to have been defined in the scope in which the 956 // anonymous union is declared. 957 Owner->makeDeclVisibleInContext(*F); 958 S->AddDecl(*F); 959 IdResolver.AddDecl(*F); 960 } 961 } else if (const RecordType *InnerRecordType 962 = (*F)->getType()->getAsRecordType()) { 963 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 964 if (InnerRecord->isAnonymousStructOrUnion()) 965 Invalid = Invalid || 966 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 967 } 968 } 969 970 return Invalid; 971} 972 973/// ActOnAnonymousStructOrUnion - Handle the declaration of an 974/// anonymous structure or union. Anonymous unions are a C++ feature 975/// (C++ [class.union]) and a GNU C extension; anonymous structures 976/// are a GNU C and GNU C++ extension. 977Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 978 RecordDecl *Record) { 979 DeclContext *Owner = Record->getDeclContext(); 980 981 // Diagnose whether this anonymous struct/union is an extension. 982 if (Record->isUnion() && !getLangOptions().CPlusPlus) 983 Diag(Record->getLocation(), diag::ext_anonymous_union); 984 else if (!Record->isUnion()) 985 Diag(Record->getLocation(), diag::ext_anonymous_struct); 986 987 // C and C++ require different kinds of checks for anonymous 988 // structs/unions. 989 bool Invalid = false; 990 if (getLangOptions().CPlusPlus) { 991 const char* PrevSpec = 0; 992 // C++ [class.union]p3: 993 // Anonymous unions declared in a named namespace or in the 994 // global namespace shall be declared static. 995 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 996 (isa<TranslationUnitDecl>(Owner) || 997 (isa<NamespaceDecl>(Owner) && 998 cast<NamespaceDecl>(Owner)->getDeclName()))) { 999 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1000 Invalid = true; 1001 1002 // Recover by adding 'static'. 1003 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1004 } 1005 // C++ [class.union]p3: 1006 // A storage class is not allowed in a declaration of an 1007 // anonymous union in a class scope. 1008 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1009 isa<RecordDecl>(Owner)) { 1010 Diag(DS.getStorageClassSpecLoc(), 1011 diag::err_anonymous_union_with_storage_spec); 1012 Invalid = true; 1013 1014 // Recover by removing the storage specifier. 1015 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1016 PrevSpec); 1017 } 1018 1019 // C++ [class.union]p2: 1020 // The member-specification of an anonymous union shall only 1021 // define non-static data members. [Note: nested types and 1022 // functions cannot be declared within an anonymous union. ] 1023 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1024 MemEnd = Record->decls_end(); 1025 Mem != MemEnd; ++Mem) { 1026 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1027 // C++ [class.union]p3: 1028 // An anonymous union shall not have private or protected 1029 // members (clause 11). 1030 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1031 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1032 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1033 Invalid = true; 1034 } 1035 } else if ((*Mem)->isImplicit()) { 1036 // Any implicit members are fine. 1037 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1038 // This is a type that showed up in an 1039 // elaborated-type-specifier inside the anonymous struct or 1040 // union, but which actually declares a type outside of the 1041 // anonymous struct or union. It's okay. 1042 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1043 if (!MemRecord->isAnonymousStructOrUnion() && 1044 MemRecord->getDeclName()) { 1045 // This is a nested type declaration. 1046 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1047 << (int)Record->isUnion(); 1048 Invalid = true; 1049 } 1050 } else { 1051 // We have something that isn't a non-static data 1052 // member. Complain about it. 1053 unsigned DK = diag::err_anonymous_record_bad_member; 1054 if (isa<TypeDecl>(*Mem)) 1055 DK = diag::err_anonymous_record_with_type; 1056 else if (isa<FunctionDecl>(*Mem)) 1057 DK = diag::err_anonymous_record_with_function; 1058 else if (isa<VarDecl>(*Mem)) 1059 DK = diag::err_anonymous_record_with_static; 1060 Diag((*Mem)->getLocation(), DK) 1061 << (int)Record->isUnion(); 1062 Invalid = true; 1063 } 1064 } 1065 } 1066 1067 if (!Record->isUnion() && !Owner->isRecord()) { 1068 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1069 << (int)getLangOptions().CPlusPlus; 1070 Invalid = true; 1071 } 1072 1073 // Create a declaration for this anonymous struct/union. 1074 NamedDecl *Anon = 0; 1075 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1076 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1077 /*IdentifierInfo=*/0, 1078 Context.getTypeDeclType(Record), 1079 /*BitWidth=*/0, /*Mutable=*/false); 1080 Anon->setAccess(AS_public); 1081 if (getLangOptions().CPlusPlus) 1082 FieldCollector->Add(cast<FieldDecl>(Anon)); 1083 } else { 1084 VarDecl::StorageClass SC; 1085 switch (DS.getStorageClassSpec()) { 1086 default: assert(0 && "Unknown storage class!"); 1087 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1088 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1089 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1090 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1091 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1092 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1093 case DeclSpec::SCS_mutable: 1094 // mutable can only appear on non-static class members, so it's always 1095 // an error here 1096 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1097 Invalid = true; 1098 SC = VarDecl::None; 1099 break; 1100 } 1101 1102 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1103 /*IdentifierInfo=*/0, 1104 Context.getTypeDeclType(Record), 1105 SC, DS.getSourceRange().getBegin()); 1106 } 1107 Anon->setImplicit(); 1108 1109 // Add the anonymous struct/union object to the current 1110 // context. We'll be referencing this object when we refer to one of 1111 // its members. 1112 Owner->addDecl(Anon); 1113 1114 // Inject the members of the anonymous struct/union into the owning 1115 // context and into the identifier resolver chain for name lookup 1116 // purposes. 1117 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1118 Invalid = true; 1119 1120 // Mark this as an anonymous struct/union type. Note that we do not 1121 // do this until after we have already checked and injected the 1122 // members of this anonymous struct/union type, because otherwise 1123 // the members could be injected twice: once by DeclContext when it 1124 // builds its lookup table, and once by 1125 // InjectAnonymousStructOrUnionMembers. 1126 Record->setAnonymousStructOrUnion(true); 1127 1128 if (Invalid) 1129 Anon->setInvalidDecl(); 1130 1131 return Anon; 1132} 1133 1134 1135/// GetNameForDeclarator - Determine the full declaration name for the 1136/// given Declarator. 1137DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1138 switch (D.getKind()) { 1139 case Declarator::DK_Abstract: 1140 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1141 return DeclarationName(); 1142 1143 case Declarator::DK_Normal: 1144 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1145 return DeclarationName(D.getIdentifier()); 1146 1147 case Declarator::DK_Constructor: { 1148 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1149 Ty = Context.getCanonicalType(Ty); 1150 return Context.DeclarationNames.getCXXConstructorName(Ty); 1151 } 1152 1153 case Declarator::DK_Destructor: { 1154 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1155 Ty = Context.getCanonicalType(Ty); 1156 return Context.DeclarationNames.getCXXDestructorName(Ty); 1157 } 1158 1159 case Declarator::DK_Conversion: { 1160 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1161 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1162 Ty = Context.getCanonicalType(Ty); 1163 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1164 } 1165 1166 case Declarator::DK_Operator: 1167 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1168 return Context.DeclarationNames.getCXXOperatorName( 1169 D.getOverloadedOperator()); 1170 } 1171 1172 assert(false && "Unknown name kind"); 1173 return DeclarationName(); 1174} 1175 1176/// isNearlyMatchingFunction - Determine whether the C++ functions 1177/// Declaration and Definition are "nearly" matching. This heuristic 1178/// is used to improve diagnostics in the case where an out-of-line 1179/// function definition doesn't match any declaration within 1180/// the class or namespace. 1181static bool isNearlyMatchingFunction(ASTContext &Context, 1182 FunctionDecl *Declaration, 1183 FunctionDecl *Definition) { 1184 if (Declaration->param_size() != Definition->param_size()) 1185 return false; 1186 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1187 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1188 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1189 1190 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1191 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1192 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1193 return false; 1194 } 1195 1196 return true; 1197} 1198 1199Sema::DeclTy * 1200Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1201 bool IsFunctionDefinition) { 1202 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1203 DeclarationName Name = GetNameForDeclarator(D); 1204 1205 // All of these full declarators require an identifier. If it doesn't have 1206 // one, the ParsedFreeStandingDeclSpec action should be used. 1207 if (!Name) { 1208 if (!D.getInvalidType()) // Reject this if we think it is valid. 1209 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1210 diag::err_declarator_need_ident) 1211 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1212 return 0; 1213 } 1214 1215 // The scope passed in may not be a decl scope. Zip up the scope tree until 1216 // we find one that is. 1217 while ((S->getFlags() & Scope::DeclScope) == 0 || 1218 (S->getFlags() & Scope::TemplateParamScope) != 0) 1219 S = S->getParent(); 1220 1221 DeclContext *DC; 1222 NamedDecl *PrevDecl; 1223 NamedDecl *New; 1224 bool InvalidDecl = false; 1225 1226 QualType R = GetTypeForDeclarator(D, S); 1227 if (R.isNull()) { 1228 InvalidDecl = true; 1229 R = Context.IntTy; 1230 } 1231 1232 // See if this is a redefinition of a variable in the same scope. 1233 if (D.getCXXScopeSpec().isInvalid()) { 1234 DC = CurContext; 1235 PrevDecl = 0; 1236 InvalidDecl = true; 1237 } else if (!D.getCXXScopeSpec().isSet()) { 1238 LookupNameKind NameKind = LookupOrdinaryName; 1239 1240 // If the declaration we're planning to build will be a function 1241 // or object with linkage, then look for another declaration with 1242 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1243 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1244 /* Do nothing*/; 1245 else if (R->isFunctionType()) { 1246 if (CurContext->isFunctionOrMethod()) 1247 NameKind = LookupRedeclarationWithLinkage; 1248 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1249 NameKind = LookupRedeclarationWithLinkage; 1250 1251 DC = CurContext; 1252 PrevDecl = LookupName(S, Name, NameKind, true, 1253 D.getDeclSpec().getStorageClassSpec() != 1254 DeclSpec::SCS_static, 1255 D.getIdentifierLoc()); 1256 } else { // Something like "int foo::x;" 1257 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1258 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1259 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1260 1261 // C++ 7.3.1.2p2: 1262 // Members (including explicit specializations of templates) of a named 1263 // namespace can also be defined outside that namespace by explicit 1264 // qualification of the name being defined, provided that the entity being 1265 // defined was already declared in the namespace and the definition appears 1266 // after the point of declaration in a namespace that encloses the 1267 // declarations namespace. 1268 // 1269 // Note that we only check the context at this point. We don't yet 1270 // have enough information to make sure that PrevDecl is actually 1271 // the declaration we want to match. For example, given: 1272 // 1273 // class X { 1274 // void f(); 1275 // void f(float); 1276 // }; 1277 // 1278 // void X::f(int) { } // ill-formed 1279 // 1280 // In this case, PrevDecl will point to the overload set 1281 // containing the two f's declared in X, but neither of them 1282 // matches. 1283 1284 // First check whether we named the global scope. 1285 if (isa<TranslationUnitDecl>(DC)) { 1286 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1287 << Name << D.getCXXScopeSpec().getRange(); 1288 } else if (!CurContext->Encloses(DC)) { 1289 // The qualifying scope doesn't enclose the original declaration. 1290 // Emit diagnostic based on current scope. 1291 SourceLocation L = D.getIdentifierLoc(); 1292 SourceRange R = D.getCXXScopeSpec().getRange(); 1293 if (isa<FunctionDecl>(CurContext)) 1294 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1295 else 1296 Diag(L, diag::err_invalid_declarator_scope) 1297 << Name << cast<NamedDecl>(DC) << R; 1298 InvalidDecl = true; 1299 } 1300 } 1301 1302 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1303 // Maybe we will complain about the shadowed template parameter. 1304 InvalidDecl = InvalidDecl 1305 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1306 // Just pretend that we didn't see the previous declaration. 1307 PrevDecl = 0; 1308 } 1309 1310 // In C++, the previous declaration we find might be a tag type 1311 // (class or enum). In this case, the new declaration will hide the 1312 // tag type. Note that this does does not apply if we're declaring a 1313 // typedef (C++ [dcl.typedef]p4). 1314 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1315 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1316 PrevDecl = 0; 1317 1318 bool Redeclaration = false; 1319 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1320 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1321 InvalidDecl, Redeclaration); 1322 } else if (R->isFunctionType()) { 1323 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1324 IsFunctionDefinition, InvalidDecl, 1325 Redeclaration); 1326 } else { 1327 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1328 InvalidDecl, Redeclaration); 1329 } 1330 1331 if (New == 0) 1332 return 0; 1333 1334 // Set the lexical context. If the declarator has a C++ scope specifier, the 1335 // lexical context will be different from the semantic context. 1336 New->setLexicalDeclContext(CurContext); 1337 1338 // If this has an identifier and is not an invalid redeclaration, 1339 // add it to the scope stack. 1340 if (Name && !(Redeclaration && InvalidDecl)) 1341 PushOnScopeChains(New, S); 1342 // If any semantic error occurred, mark the decl as invalid. 1343 if (D.getInvalidType() || InvalidDecl) 1344 New->setInvalidDecl(); 1345 1346 return New; 1347} 1348 1349/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1350/// types into constant array types in certain situations which would otherwise 1351/// be errors (for GCC compatibility). 1352static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1353 ASTContext &Context, 1354 bool &SizeIsNegative) { 1355 // This method tries to turn a variable array into a constant 1356 // array even when the size isn't an ICE. This is necessary 1357 // for compatibility with code that depends on gcc's buggy 1358 // constant expression folding, like struct {char x[(int)(char*)2];} 1359 SizeIsNegative = false; 1360 1361 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1362 QualType Pointee = PTy->getPointeeType(); 1363 QualType FixedType = 1364 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1365 if (FixedType.isNull()) return FixedType; 1366 FixedType = Context.getPointerType(FixedType); 1367 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1368 return FixedType; 1369 } 1370 1371 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1372 if (!VLATy) 1373 return QualType(); 1374 // FIXME: We should probably handle this case 1375 if (VLATy->getElementType()->isVariablyModifiedType()) 1376 return QualType(); 1377 1378 Expr::EvalResult EvalResult; 1379 if (!VLATy->getSizeExpr() || 1380 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1381 !EvalResult.Val.isInt()) 1382 return QualType(); 1383 1384 llvm::APSInt &Res = EvalResult.Val.getInt(); 1385 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1386 return Context.getConstantArrayType(VLATy->getElementType(), 1387 Res, ArrayType::Normal, 0); 1388 1389 SizeIsNegative = true; 1390 return QualType(); 1391} 1392 1393/// \brief Register the given locally-scoped external C declaration so 1394/// that it can be found later for redeclarations 1395void 1396Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1397 Scope *S) { 1398 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1399 "Decl is not a locally-scoped decl!"); 1400 // Note that we have a locally-scoped external with this name. 1401 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1402 1403 if (!PrevDecl) 1404 return; 1405 1406 // If there was a previous declaration of this variable, it may be 1407 // in our identifier chain. Update the identifier chain with the new 1408 // declaration. 1409 if (IdResolver.ReplaceDecl(PrevDecl, ND)) { 1410 // The previous declaration was found on the identifer resolver 1411 // chain, so remove it from its scope. 1412 while (S && !S->isDeclScope(PrevDecl)) 1413 S = S->getParent(); 1414 1415 if (S) 1416 S->RemoveDecl(PrevDecl); 1417 } 1418} 1419 1420NamedDecl* 1421Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1422 QualType R, Decl* LastDeclarator, 1423 Decl* PrevDecl, bool& InvalidDecl, 1424 bool &Redeclaration) { 1425 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1426 if (D.getCXXScopeSpec().isSet()) { 1427 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1428 << D.getCXXScopeSpec().getRange(); 1429 InvalidDecl = true; 1430 // Pretend we didn't see the scope specifier. 1431 DC = 0; 1432 } 1433 1434 // Check that there are no default arguments (C++ only). 1435 if (getLangOptions().CPlusPlus) 1436 CheckExtraCXXDefaultArguments(D); 1437 1438 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1439 if (!NewTD) return 0; 1440 1441 // Handle attributes prior to checking for duplicates in MergeVarDecl 1442 ProcessDeclAttributes(NewTD, D); 1443 // Merge the decl with the existing one if appropriate. If the decl is 1444 // in an outer scope, it isn't the same thing. 1445 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1446 Redeclaration = true; 1447 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1448 InvalidDecl = true; 1449 } 1450 1451 if (S->getFnParent() == 0) { 1452 QualType T = NewTD->getUnderlyingType(); 1453 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1454 // then it shall have block scope. 1455 if (T->isVariablyModifiedType()) { 1456 bool SizeIsNegative; 1457 QualType FixedTy = 1458 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1459 if (!FixedTy.isNull()) { 1460 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1461 NewTD->setUnderlyingType(FixedTy); 1462 } else { 1463 if (SizeIsNegative) 1464 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1465 else if (T->isVariableArrayType()) 1466 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1467 else 1468 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1469 InvalidDecl = true; 1470 } 1471 } 1472 } 1473 return NewTD; 1474} 1475 1476/// \brief Determines whether the given declaration is an out-of-scope 1477/// previous declaration. 1478/// 1479/// This routine should be invoked when name lookup has found a 1480/// previous declaration (PrevDecl) that is not in the scope where a 1481/// new declaration by the same name is being introduced. If the new 1482/// declaration occurs in a local scope, previous declarations with 1483/// linkage may still be considered previous declarations (C99 1484/// 6.2.2p4-5, C++ [basic.link]p6). 1485/// 1486/// \param PrevDecl the previous declaration found by name 1487/// lookup 1488/// 1489/// \param DC the context in which the new declaration is being 1490/// declared. 1491/// 1492/// \returns true if PrevDecl is an out-of-scope previous declaration 1493/// for a new delcaration with the same name. 1494static bool 1495isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1496 ASTContext &Context) { 1497 if (!PrevDecl) 1498 return 0; 1499 1500 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1501 // case we need to check each of the overloaded functions. 1502 if (!PrevDecl->hasLinkage()) 1503 return false; 1504 1505 if (Context.getLangOptions().CPlusPlus) { 1506 // C++ [basic.link]p6: 1507 // If there is a visible declaration of an entity with linkage 1508 // having the same name and type, ignoring entities declared 1509 // outside the innermost enclosing namespace scope, the block 1510 // scope declaration declares that same entity and receives the 1511 // linkage of the previous declaration. 1512 DeclContext *OuterContext = DC->getLookupContext(); 1513 if (!OuterContext->isFunctionOrMethod()) 1514 // This rule only applies to block-scope declarations. 1515 return false; 1516 else { 1517 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1518 if (PrevOuterContext->isRecord()) 1519 // We found a member function: ignore it. 1520 return false; 1521 else { 1522 // Find the innermost enclosing namespace for the new and 1523 // previous declarations. 1524 while (!OuterContext->isFileContext()) 1525 OuterContext = OuterContext->getParent(); 1526 while (!PrevOuterContext->isFileContext()) 1527 PrevOuterContext = PrevOuterContext->getParent(); 1528 1529 // The previous declaration is in a different namespace, so it 1530 // isn't the same function. 1531 if (OuterContext->getPrimaryContext() != 1532 PrevOuterContext->getPrimaryContext()) 1533 return false; 1534 } 1535 } 1536 } 1537 1538 return true; 1539} 1540 1541NamedDecl* 1542Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1543 QualType R, Decl* LastDeclarator, 1544 NamedDecl* PrevDecl, bool& InvalidDecl, 1545 bool &Redeclaration) { 1546 DeclarationName Name = GetNameForDeclarator(D); 1547 1548 // Check that there are no default arguments (C++ only). 1549 if (getLangOptions().CPlusPlus) 1550 CheckExtraCXXDefaultArguments(D); 1551 1552 if (R.getTypePtr()->isObjCInterfaceType()) { 1553 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object); 1554 InvalidDecl = true; 1555 } 1556 1557 VarDecl *NewVD; 1558 VarDecl::StorageClass SC; 1559 switch (D.getDeclSpec().getStorageClassSpec()) { 1560 default: assert(0 && "Unknown storage class!"); 1561 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1562 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1563 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1564 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1565 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1566 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1567 case DeclSpec::SCS_mutable: 1568 // mutable can only appear on non-static class members, so it's always 1569 // an error here 1570 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1571 InvalidDecl = true; 1572 SC = VarDecl::None; 1573 break; 1574 } 1575 1576 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1577 if (!II) { 1578 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1579 << Name.getAsString(); 1580 return 0; 1581 } 1582 1583 if (DC->isRecord()) { 1584 // This is a static data member for a C++ class. 1585 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1586 D.getIdentifierLoc(), II, 1587 R); 1588 } else { 1589 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1590 if (S->getFnParent() == 0) { 1591 // C99 6.9p2: The storage-class specifiers auto and register shall not 1592 // appear in the declaration specifiers in an external declaration. 1593 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1594 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1595 InvalidDecl = true; 1596 } 1597 } 1598 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1599 II, R, SC, 1600 // FIXME: Move to DeclGroup... 1601 D.getDeclSpec().getSourceRange().getBegin()); 1602 NewVD->setThreadSpecified(ThreadSpecified); 1603 } 1604 NewVD->setNextDeclarator(LastDeclarator); 1605 1606 // Handle attributes prior to checking for duplicates in MergeVarDecl 1607 ProcessDeclAttributes(NewVD, D); 1608 1609 // Handle GNU asm-label extension (encoded as an attribute). 1610 if (Expr *E = (Expr*) D.getAsmLabel()) { 1611 // The parser guarantees this is a string. 1612 StringLiteral *SE = cast<StringLiteral>(E); 1613 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1614 SE->getByteLength()))); 1615 } 1616 1617 // Emit an error if an address space was applied to decl with local storage. 1618 // This includes arrays of objects with address space qualifiers, but not 1619 // automatic variables that point to other address spaces. 1620 // ISO/IEC TR 18037 S5.1.2 1621 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1622 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1623 InvalidDecl = true; 1624 } 1625 1626 if (NewVD->hasLocalStorage() && NewVD->getType().isObjCGCWeak()) { 1627 Diag(D.getIdentifierLoc(), diag::warn_attribute_weak_on_local); 1628 } 1629 1630 bool isIllegalVLA = R->isVariableArrayType() && NewVD->hasGlobalStorage(); 1631 bool isIllegalVM = R->isVariablyModifiedType() && NewVD->hasLinkage(); 1632 if (isIllegalVLA || isIllegalVM) { 1633 bool SizeIsNegative; 1634 QualType FixedTy = 1635 TryToFixInvalidVariablyModifiedType(R, Context, SizeIsNegative); 1636 if (!FixedTy.isNull()) { 1637 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1638 NewVD->setType(FixedTy); 1639 } else if (R->isVariableArrayType()) { 1640 NewVD->setInvalidDecl(); 1641 1642 const VariableArrayType *VAT = Context.getAsVariableArrayType(R); 1643 // FIXME: This won't give the correct result for 1644 // int a[10][n]; 1645 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1646 1647 if (NewVD->isFileVarDecl()) 1648 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1649 << SizeRange; 1650 else if (NewVD->getStorageClass() == VarDecl::Static) 1651 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1652 << SizeRange; 1653 else 1654 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1655 << SizeRange; 1656 } else { 1657 InvalidDecl = true; 1658 1659 if (NewVD->isFileVarDecl()) 1660 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1661 else 1662 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1663 } 1664 } 1665 1666 // If name lookup finds a previous declaration that is not in the 1667 // same scope as the new declaration, this may still be an 1668 // acceptable redeclaration. 1669 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1670 !(NewVD->hasLinkage() && 1671 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1672 PrevDecl = 0; 1673 1674 if (!PrevDecl && NewVD->isExternC(Context)) { 1675 // Since we did not find anything by this name and we're declaring 1676 // an extern "C" variable, look for a non-visible extern "C" 1677 // declaration with the same name. 1678 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1679 = LocallyScopedExternalDecls.find(Name); 1680 if (Pos != LocallyScopedExternalDecls.end()) 1681 PrevDecl = Pos->second; 1682 } 1683 1684 // Merge the decl with the existing one if appropriate. 1685 if (PrevDecl) { 1686 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1687 // The user tried to define a non-static data member 1688 // out-of-line (C++ [dcl.meaning]p1). 1689 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1690 << D.getCXXScopeSpec().getRange(); 1691 NewVD->Destroy(Context); 1692 return 0; 1693 } 1694 1695 Redeclaration = true; 1696 if (MergeVarDecl(NewVD, PrevDecl)) 1697 InvalidDecl = true; 1698 1699 if (D.getCXXScopeSpec().isSet()) { 1700 // No previous declaration in the qualifying scope. 1701 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1702 << Name << D.getCXXScopeSpec().getRange(); 1703 InvalidDecl = true; 1704 } 1705 } 1706 1707 if (!InvalidDecl && R->isVoidType() && !NewVD->hasExternalStorage()) { 1708 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1709 << R; 1710 InvalidDecl = true; 1711 } 1712 1713 1714 // If this is a locally-scoped extern C variable, update the map of 1715 // such variables. 1716 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1717 !InvalidDecl) 1718 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1719 1720 return NewVD; 1721} 1722 1723NamedDecl* 1724Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1725 QualType R, Decl *LastDeclarator, 1726 NamedDecl* PrevDecl, bool IsFunctionDefinition, 1727 bool& InvalidDecl, bool &Redeclaration) { 1728 assert(R.getTypePtr()->isFunctionType()); 1729 1730 DeclarationName Name = GetNameForDeclarator(D); 1731 FunctionDecl::StorageClass SC = FunctionDecl::None; 1732 switch (D.getDeclSpec().getStorageClassSpec()) { 1733 default: assert(0 && "Unknown storage class!"); 1734 case DeclSpec::SCS_auto: 1735 case DeclSpec::SCS_register: 1736 case DeclSpec::SCS_mutable: 1737 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1738 diag::err_typecheck_sclass_func); 1739 InvalidDecl = true; 1740 break; 1741 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1742 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1743 case DeclSpec::SCS_static: { 1744 if (DC->getLookupContext()->isFunctionOrMethod()) { 1745 // C99 6.7.1p5: 1746 // The declaration of an identifier for a function that has 1747 // block scope shall have no explicit storage-class specifier 1748 // other than extern 1749 // See also (C++ [dcl.stc]p4). 1750 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1751 diag::err_static_block_func); 1752 SC = FunctionDecl::None; 1753 } else 1754 SC = FunctionDecl::Static; 1755 break; 1756 } 1757 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1758 } 1759 1760 bool isInline = D.getDeclSpec().isInlineSpecified(); 1761 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1762 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1763 1764 FunctionDecl *NewFD; 1765 if (D.getKind() == Declarator::DK_Constructor) { 1766 // This is a C++ constructor declaration. 1767 assert(DC->isRecord() && 1768 "Constructors can only be declared in a member context"); 1769 1770 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1771 1772 // Create the new declaration 1773 NewFD = CXXConstructorDecl::Create(Context, 1774 cast<CXXRecordDecl>(DC), 1775 D.getIdentifierLoc(), Name, R, 1776 isExplicit, isInline, 1777 /*isImplicitlyDeclared=*/false); 1778 1779 if (InvalidDecl) 1780 NewFD->setInvalidDecl(); 1781 } else if (D.getKind() == Declarator::DK_Destructor) { 1782 // This is a C++ destructor declaration. 1783 if (DC->isRecord()) { 1784 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1785 1786 NewFD = CXXDestructorDecl::Create(Context, 1787 cast<CXXRecordDecl>(DC), 1788 D.getIdentifierLoc(), Name, R, 1789 isInline, 1790 /*isImplicitlyDeclared=*/false); 1791 1792 if (InvalidDecl) 1793 NewFD->setInvalidDecl(); 1794 } else { 1795 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1796 1797 // Create a FunctionDecl to satisfy the function definition parsing 1798 // code path. 1799 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1800 Name, R, SC, isInline, 1801 /*hasPrototype=*/true, 1802 // FIXME: Move to DeclGroup... 1803 D.getDeclSpec().getSourceRange().getBegin()); 1804 InvalidDecl = true; 1805 NewFD->setInvalidDecl(); 1806 } 1807 } else if (D.getKind() == Declarator::DK_Conversion) { 1808 if (!DC->isRecord()) { 1809 Diag(D.getIdentifierLoc(), 1810 diag::err_conv_function_not_member); 1811 return 0; 1812 } else { 1813 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1814 1815 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1816 D.getIdentifierLoc(), Name, R, 1817 isInline, isExplicit); 1818 1819 if (InvalidDecl) 1820 NewFD->setInvalidDecl(); 1821 } 1822 } else if (DC->isRecord()) { 1823 // This is a C++ method declaration. 1824 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1825 D.getIdentifierLoc(), Name, R, 1826 (SC == FunctionDecl::Static), isInline); 1827 } else { 1828 NewFD = FunctionDecl::Create(Context, DC, 1829 D.getIdentifierLoc(), 1830 Name, R, SC, isInline, 1831 /*hasPrototype=*/ 1832 (getLangOptions().CPlusPlus || 1833 (D.getNumTypeObjects() && 1834 D.getTypeObject(0).Fun.hasPrototype)), 1835 // FIXME: Move to DeclGroup... 1836 D.getDeclSpec().getSourceRange().getBegin()); 1837 } 1838 NewFD->setNextDeclarator(LastDeclarator); 1839 1840 // Set the lexical context. If the declarator has a C++ 1841 // scope specifier, the lexical context will be different 1842 // from the semantic context. 1843 NewFD->setLexicalDeclContext(CurContext); 1844 1845 // Handle GNU asm-label extension (encoded as an attribute). 1846 if (Expr *E = (Expr*) D.getAsmLabel()) { 1847 // The parser guarantees this is a string. 1848 StringLiteral *SE = cast<StringLiteral>(E); 1849 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1850 SE->getByteLength()))); 1851 } 1852 1853 // Copy the parameter declarations from the declarator D to 1854 // the function declaration NewFD, if they are available. 1855 if (D.getNumTypeObjects() > 0) { 1856 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1857 1858 // Create Decl objects for each parameter, adding them to the 1859 // FunctionDecl. 1860 llvm::SmallVector<ParmVarDecl*, 16> Params; 1861 1862 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1863 // function that takes no arguments, not a function that takes a 1864 // single void argument. 1865 // We let through "const void" here because Sema::GetTypeForDeclarator 1866 // already checks for that case. 1867 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1868 FTI.ArgInfo[0].Param && 1869 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1870 // empty arg list, don't push any params. 1871 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1872 1873 // In C++, the empty parameter-type-list must be spelled "void"; a 1874 // typedef of void is not permitted. 1875 if (getLangOptions().CPlusPlus && 1876 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1877 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1878 } 1879 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1880 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1881 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1882 } 1883 1884 NewFD->setParams(Context, &Params[0], Params.size()); 1885 } else if (R->getAsTypedefType()) { 1886 // When we're declaring a function with a typedef, as in the 1887 // following example, we'll need to synthesize (unnamed) 1888 // parameters for use in the declaration. 1889 // 1890 // @code 1891 // typedef void fn(int); 1892 // fn f; 1893 // @endcode 1894 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 1895 if (!FT) { 1896 // This is a typedef of a function with no prototype, so we 1897 // don't need to do anything. 1898 } else if ((FT->getNumArgs() == 0) || 1899 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1900 FT->getArgType(0)->isVoidType())) { 1901 // This is a zero-argument function. We don't need to do anything. 1902 } else { 1903 // Synthesize a parameter for each argument type. 1904 llvm::SmallVector<ParmVarDecl*, 16> Params; 1905 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 1906 ArgType != FT->arg_type_end(); ++ArgType) { 1907 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 1908 SourceLocation(), 0, 1909 *ArgType, VarDecl::None, 1910 0); 1911 Param->setImplicit(); 1912 Params.push_back(Param); 1913 } 1914 1915 NewFD->setParams(Context, &Params[0], Params.size()); 1916 } 1917 } 1918 1919 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1920 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1921 else if (isa<CXXDestructorDecl>(NewFD)) { 1922 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1923 Record->setUserDeclaredDestructor(true); 1924 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1925 // user-defined destructor. 1926 Record->setPOD(false); 1927 } else if (CXXConversionDecl *Conversion = 1928 dyn_cast<CXXConversionDecl>(NewFD)) 1929 ActOnConversionDeclarator(Conversion); 1930 1931 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1932 if (NewFD->isOverloadedOperator() && 1933 CheckOverloadedOperatorDeclaration(NewFD)) 1934 NewFD->setInvalidDecl(); 1935 1936 // If name lookup finds a previous declaration that is not in the 1937 // same scope as the new declaration, this may still be an 1938 // acceptable redeclaration. 1939 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1940 !(NewFD->hasLinkage() && 1941 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1942 PrevDecl = 0; 1943 1944 if (!PrevDecl && NewFD->isExternC(Context)) { 1945 // Since we did not find anything by this name and we're declaring 1946 // an extern "C" function, look for a non-visible extern "C" 1947 // declaration with the same name. 1948 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1949 = LocallyScopedExternalDecls.find(Name); 1950 if (Pos != LocallyScopedExternalDecls.end()) 1951 PrevDecl = Pos->second; 1952 } 1953 1954 // Merge or overload the declaration with an existing declaration of 1955 // the same name, if appropriate. 1956 bool OverloadableAttrRequired = false; 1957 if (PrevDecl) { 1958 // Determine whether NewFD is an overload of PrevDecl or 1959 // a declaration that requires merging. If it's an overload, 1960 // there's no more work to do here; we'll just add the new 1961 // function to the scope. 1962 OverloadedFunctionDecl::function_iterator MatchedDecl; 1963 1964 if (!getLangOptions().CPlusPlus && 1965 AllowOverloadingOfFunction(PrevDecl, Context)) { 1966 OverloadableAttrRequired = true; 1967 1968 // Functions marked "overloadable" must have a prototype (that 1969 // we can't get through declaration merging). 1970 if (!R->getAsFunctionProtoType()) { 1971 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 1972 << NewFD; 1973 InvalidDecl = true; 1974 Redeclaration = true; 1975 1976 // Turn this into a variadic function with no parameters. 1977 R = Context.getFunctionType(R->getAsFunctionType()->getResultType(), 1978 0, 0, true, 0); 1979 NewFD->setType(R); 1980 } 1981 } 1982 1983 if (PrevDecl && 1984 (!AllowOverloadingOfFunction(PrevDecl, Context) || 1985 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 1986 Redeclaration = true; 1987 Decl *OldDecl = PrevDecl; 1988 1989 // If PrevDecl was an overloaded function, extract the 1990 // FunctionDecl that matched. 1991 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1992 OldDecl = *MatchedDecl; 1993 1994 // NewFD and PrevDecl represent declarations that need to be 1995 // merged. 1996 if (MergeFunctionDecl(NewFD, OldDecl)) 1997 InvalidDecl = true; 1998 1999 if (!InvalidDecl) { 2000 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2001 2002 // An out-of-line member function declaration must also be a 2003 // definition (C++ [dcl.meaning]p1). 2004 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 2005 !InvalidDecl) { 2006 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2007 << D.getCXXScopeSpec().getRange(); 2008 NewFD->setInvalidDecl(); 2009 } 2010 } 2011 } 2012 } 2013 2014 if (D.getCXXScopeSpec().isSet() && 2015 (!PrevDecl || !Redeclaration)) { 2016 // The user tried to provide an out-of-line definition for a 2017 // function that is a member of a class or namespace, but there 2018 // was no such member function declared (C++ [class.mfct]p2, 2019 // C++ [namespace.memdef]p2). For example: 2020 // 2021 // class X { 2022 // void f() const; 2023 // }; 2024 // 2025 // void X::f() { } // ill-formed 2026 // 2027 // Complain about this problem, and attempt to suggest close 2028 // matches (e.g., those that differ only in cv-qualifiers and 2029 // whether the parameter types are references). 2030 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2031 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2032 InvalidDecl = true; 2033 2034 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2035 true); 2036 assert(!Prev.isAmbiguous() && 2037 "Cannot have an ambiguity in previous-declaration lookup"); 2038 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2039 Func != FuncEnd; ++Func) { 2040 if (isa<FunctionDecl>(*Func) && 2041 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2042 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2043 } 2044 2045 PrevDecl = 0; 2046 } 2047 2048 // Handle attributes. We need to have merged decls when handling attributes 2049 // (for example to check for conflicts, etc). 2050 ProcessDeclAttributes(NewFD, D); 2051 AddKnownFunctionAttributes(NewFD); 2052 2053 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2054 // If a function name is overloadable in C, then every function 2055 // with that name must be marked "overloadable". 2056 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2057 << Redeclaration << NewFD; 2058 if (PrevDecl) 2059 Diag(PrevDecl->getLocation(), 2060 diag::note_attribute_overloadable_prev_overload); 2061 NewFD->addAttr(::new (Context) OverloadableAttr()); 2062 } 2063 2064 if (getLangOptions().CPlusPlus) { 2065 // In C++, check default arguments now that we have merged decls. Unless 2066 // the lexical context is the class, because in this case this is done 2067 // during delayed parsing anyway. 2068 if (!CurContext->isRecord()) 2069 CheckCXXDefaultArguments(NewFD); 2070 2071 // An out-of-line member function declaration must also be a 2072 // definition (C++ [dcl.meaning]p1). 2073 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2074 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2075 << D.getCXXScopeSpec().getRange(); 2076 InvalidDecl = true; 2077 } 2078 } 2079 2080 // If this is a locally-scoped extern C function, update the 2081 // map of such names. 2082 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2083 && !InvalidDecl) 2084 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2085 2086 return NewFD; 2087} 2088 2089bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2090 // FIXME: Need strict checking. In C89, we need to check for 2091 // any assignment, increment, decrement, function-calls, or 2092 // commas outside of a sizeof. In C99, it's the same list, 2093 // except that the aforementioned are allowed in unevaluated 2094 // expressions. Everything else falls under the 2095 // "may accept other forms of constant expressions" exception. 2096 // (We never end up here for C++, so the constant expression 2097 // rules there don't matter.) 2098 if (Init->isConstantInitializer(Context)) 2099 return false; 2100 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2101 << Init->getSourceRange(); 2102 return true; 2103} 2104 2105void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2106 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2107} 2108 2109/// AddInitializerToDecl - Adds the initializer Init to the 2110/// declaration dcl. If DirectInit is true, this is C++ direct 2111/// initialization rather than copy initialization. 2112void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2113 Decl *RealDecl = static_cast<Decl *>(dcl); 2114 // If there is no declaration, there was an error parsing it. Just ignore 2115 // the initializer. 2116 if (RealDecl == 0) 2117 return; 2118 2119 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2120 if (!VDecl) { 2121 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2122 RealDecl->setInvalidDecl(); 2123 return; 2124 } 2125 2126 const VarDecl *Def = 0; 2127 if (VDecl->getDefinition(Def)) { 2128 Diag(VDecl->getLocation(), diag::err_redefinition) 2129 << VDecl->getDeclName(); 2130 Diag(Def->getLocation(), diag::note_previous_definition); 2131 VDecl->setInvalidDecl(); 2132 return; 2133 } 2134 2135 // Take ownership of the expression, now that we're sure we have somewhere 2136 // to put it. 2137 Expr *Init = static_cast<Expr *>(init.release()); 2138 assert(Init && "missing initializer"); 2139 2140 // Get the decls type and save a reference for later, since 2141 // CheckInitializerTypes may change it. 2142 QualType DclT = VDecl->getType(), SavT = DclT; 2143 if (VDecl->isBlockVarDecl()) { 2144 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2145 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2146 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2147 VDecl->setInvalidDecl(); 2148 } else if (!VDecl->isInvalidDecl()) { 2149 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2150 VDecl->getDeclName(), DirectInit)) 2151 VDecl->setInvalidDecl(); 2152 2153 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2154 // Don't check invalid declarations to avoid emitting useless diagnostics. 2155 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2156 if (SC == VarDecl::Static) // C99 6.7.8p4. 2157 CheckForConstantInitializer(Init, DclT); 2158 } 2159 } 2160 } else if (VDecl->isFileVarDecl()) { 2161 if (VDecl->getStorageClass() == VarDecl::Extern) 2162 Diag(VDecl->getLocation(), diag::warn_extern_init); 2163 if (!VDecl->isInvalidDecl()) 2164 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2165 VDecl->getDeclName(), DirectInit)) 2166 VDecl->setInvalidDecl(); 2167 2168 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2169 // Don't check invalid declarations to avoid emitting useless diagnostics. 2170 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2171 // C99 6.7.8p4. All file scoped initializers need to be constant. 2172 CheckForConstantInitializer(Init, DclT); 2173 } 2174 } 2175 // If the type changed, it means we had an incomplete type that was 2176 // completed by the initializer. For example: 2177 // int ary[] = { 1, 3, 5 }; 2178 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2179 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2180 VDecl->setType(DclT); 2181 Init->setType(DclT); 2182 } 2183 2184 // Attach the initializer to the decl. 2185 VDecl->setInit(Init); 2186 return; 2187} 2188 2189void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2190 Decl *RealDecl = static_cast<Decl *>(dcl); 2191 2192 // If there is no declaration, there was an error parsing it. Just ignore it. 2193 if (RealDecl == 0) 2194 return; 2195 2196 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2197 QualType Type = Var->getType(); 2198 // C++ [dcl.init.ref]p3: 2199 // The initializer can be omitted for a reference only in a 2200 // parameter declaration (8.3.5), in the declaration of a 2201 // function return type, in the declaration of a class member 2202 // within its class declaration (9.2), and where the extern 2203 // specifier is explicitly used. 2204 if (Type->isReferenceType() && 2205 Var->getStorageClass() != VarDecl::Extern && 2206 Var->getStorageClass() != VarDecl::PrivateExtern) { 2207 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2208 << Var->getDeclName() 2209 << SourceRange(Var->getLocation(), Var->getLocation()); 2210 Var->setInvalidDecl(); 2211 return; 2212 } 2213 2214 // C++ [dcl.init]p9: 2215 // 2216 // If no initializer is specified for an object, and the object 2217 // is of (possibly cv-qualified) non-POD class type (or array 2218 // thereof), the object shall be default-initialized; if the 2219 // object is of const-qualified type, the underlying class type 2220 // shall have a user-declared default constructor. 2221 if (getLangOptions().CPlusPlus) { 2222 QualType InitType = Type; 2223 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2224 InitType = Array->getElementType(); 2225 if (Var->getStorageClass() != VarDecl::Extern && 2226 Var->getStorageClass() != VarDecl::PrivateExtern && 2227 InitType->isRecordType()) { 2228 const CXXConstructorDecl *Constructor = 0; 2229 if (!RequireCompleteType(Var->getLocation(), InitType, 2230 diag::err_invalid_incomplete_type_use)) 2231 Constructor 2232 = PerformInitializationByConstructor(InitType, 0, 0, 2233 Var->getLocation(), 2234 SourceRange(Var->getLocation(), 2235 Var->getLocation()), 2236 Var->getDeclName(), 2237 IK_Default); 2238 if (!Constructor) 2239 Var->setInvalidDecl(); 2240 } 2241 } 2242 2243#if 0 2244 // FIXME: Temporarily disabled because we are not properly parsing 2245 // linkage specifications on declarations, e.g., 2246 // 2247 // extern "C" const CGPoint CGPointerZero; 2248 // 2249 // C++ [dcl.init]p9: 2250 // 2251 // If no initializer is specified for an object, and the 2252 // object is of (possibly cv-qualified) non-POD class type (or 2253 // array thereof), the object shall be default-initialized; if 2254 // the object is of const-qualified type, the underlying class 2255 // type shall have a user-declared default 2256 // constructor. Otherwise, if no initializer is specified for 2257 // an object, the object and its subobjects, if any, have an 2258 // indeterminate initial value; if the object or any of its 2259 // subobjects are of const-qualified type, the program is 2260 // ill-formed. 2261 // 2262 // This isn't technically an error in C, so we don't diagnose it. 2263 // 2264 // FIXME: Actually perform the POD/user-defined default 2265 // constructor check. 2266 if (getLangOptions().CPlusPlus && 2267 Context.getCanonicalType(Type).isConstQualified() && 2268 Var->getStorageClass() != VarDecl::Extern) 2269 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2270 << Var->getName() 2271 << SourceRange(Var->getLocation(), Var->getLocation()); 2272#endif 2273 } 2274} 2275 2276/// The declarators are chained together backwards, reverse the list. 2277Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2278 // Often we have single declarators, handle them quickly. 2279 Decl *Group = static_cast<Decl*>(group); 2280 if (Group == 0) 2281 return 0; 2282 2283 Decl *NewGroup = 0; 2284 if (Group->getNextDeclarator() == 0) 2285 NewGroup = Group; 2286 else { // reverse the list. 2287 while (Group) { 2288 Decl *Next = Group->getNextDeclarator(); 2289 Group->setNextDeclarator(NewGroup); 2290 NewGroup = Group; 2291 Group = Next; 2292 } 2293 } 2294 // Perform semantic analysis that depends on having fully processed both 2295 // the declarator and initializer. 2296 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2297 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2298 if (!IDecl) 2299 continue; 2300 QualType T = IDecl->getType(); 2301 2302 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2303 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2304 if (IDecl->isBlockVarDecl() && 2305 IDecl->getStorageClass() != VarDecl::Extern) { 2306 if (!IDecl->isInvalidDecl() && 2307 RequireCompleteType(IDecl->getLocation(), T, 2308 diag::err_typecheck_decl_incomplete_type)) 2309 IDecl->setInvalidDecl(); 2310 } 2311 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2312 // object that has file scope without an initializer, and without a 2313 // storage-class specifier or with the storage-class specifier "static", 2314 // constitutes a tentative definition. Note: A tentative definition with 2315 // external linkage is valid (C99 6.2.2p5). 2316 if (IDecl->isTentativeDefinition(Context)) { 2317 QualType CheckType = T; 2318 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2319 2320 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2321 if (ArrayT) { 2322 CheckType = ArrayT->getElementType(); 2323 DiagID = diag::err_illegal_decl_array_incomplete_type; 2324 } 2325 2326 if (IDecl->isInvalidDecl()) { 2327 // Do nothing with invalid declarations 2328 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2329 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2330 // C99 6.9.2p3: If the declaration of an identifier for an object is 2331 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2332 // declared type shall not be an incomplete type. 2333 IDecl->setInvalidDecl(); 2334 } 2335 } 2336 } 2337 return NewGroup; 2338} 2339 2340/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2341/// to introduce parameters into function prototype scope. 2342Sema::DeclTy * 2343Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2344 const DeclSpec &DS = D.getDeclSpec(); 2345 2346 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2347 VarDecl::StorageClass StorageClass = VarDecl::None; 2348 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2349 StorageClass = VarDecl::Register; 2350 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2351 Diag(DS.getStorageClassSpecLoc(), 2352 diag::err_invalid_storage_class_in_func_decl); 2353 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2354 } 2355 if (DS.isThreadSpecified()) { 2356 Diag(DS.getThreadSpecLoc(), 2357 diag::err_invalid_storage_class_in_func_decl); 2358 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2359 } 2360 2361 // Check that there are no default arguments inside the type of this 2362 // parameter (C++ only). 2363 if (getLangOptions().CPlusPlus) 2364 CheckExtraCXXDefaultArguments(D); 2365 2366 // In this context, we *do not* check D.getInvalidType(). If the declarator 2367 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2368 // though it will not reflect the user specified type. 2369 QualType parmDeclType = GetTypeForDeclarator(D, S); 2370 2371 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2372 2373 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2374 // Can this happen for params? We already checked that they don't conflict 2375 // among each other. Here they can only shadow globals, which is ok. 2376 IdentifierInfo *II = D.getIdentifier(); 2377 if (II) { 2378 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2379 if (PrevDecl->isTemplateParameter()) { 2380 // Maybe we will complain about the shadowed template parameter. 2381 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2382 // Just pretend that we didn't see the previous declaration. 2383 PrevDecl = 0; 2384 } else if (S->isDeclScope(PrevDecl)) { 2385 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2386 2387 // Recover by removing the name 2388 II = 0; 2389 D.SetIdentifier(0, D.getIdentifierLoc()); 2390 } 2391 } 2392 } 2393 2394 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2395 // Doing the promotion here has a win and a loss. The win is the type for 2396 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2397 // code generator). The loss is the orginal type isn't preserved. For example: 2398 // 2399 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2400 // int blockvardecl[5]; 2401 // sizeof(parmvardecl); // size == 4 2402 // sizeof(blockvardecl); // size == 20 2403 // } 2404 // 2405 // For expressions, all implicit conversions are captured using the 2406 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2407 // 2408 // FIXME: If a source translation tool needs to see the original type, then 2409 // we need to consider storing both types (in ParmVarDecl)... 2410 // 2411 if (parmDeclType->isArrayType()) { 2412 // int x[restrict 4] -> int *restrict 2413 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2414 } else if (parmDeclType->isFunctionType()) 2415 parmDeclType = Context.getPointerType(parmDeclType); 2416 2417 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2418 D.getIdentifierLoc(), II, 2419 parmDeclType, StorageClass, 2420 0); 2421 2422 if (D.getInvalidType()) 2423 New->setInvalidDecl(); 2424 2425 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2426 if (D.getCXXScopeSpec().isSet()) { 2427 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2428 << D.getCXXScopeSpec().getRange(); 2429 New->setInvalidDecl(); 2430 } 2431 // Parameter declarators cannot be interface types. All ObjC objects are 2432 // passed by reference. 2433 if (parmDeclType->isObjCInterfaceType()) { 2434 Diag(D.getIdentifierLoc(), diag::err_object_cannot_be_by_value) 2435 << "passed"; 2436 New->setInvalidDecl(); 2437 } 2438 2439 // Add the parameter declaration into this scope. 2440 S->AddDecl(New); 2441 if (II) 2442 IdResolver.AddDecl(New); 2443 2444 ProcessDeclAttributes(New, D); 2445 return New; 2446 2447} 2448 2449void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2450 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2451 "Not a function declarator!"); 2452 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2453 2454 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2455 // for a K&R function. 2456 if (!FTI.hasPrototype) { 2457 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2458 if (FTI.ArgInfo[i].Param == 0) { 2459 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2460 << FTI.ArgInfo[i].Ident; 2461 // Implicitly declare the argument as type 'int' for lack of a better 2462 // type. 2463 DeclSpec DS; 2464 const char* PrevSpec; // unused 2465 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2466 PrevSpec); 2467 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2468 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2469 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2470 } 2471 } 2472 } 2473} 2474 2475Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2476 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2477 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2478 "Not a function declarator!"); 2479 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2480 2481 if (FTI.hasPrototype) { 2482 // FIXME: Diagnose arguments without names in C. 2483 } 2484 2485 Scope *ParentScope = FnBodyScope->getParent(); 2486 2487 return ActOnStartOfFunctionDef(FnBodyScope, 2488 ActOnDeclarator(ParentScope, D, 0, 2489 /*IsFunctionDefinition=*/true)); 2490} 2491 2492Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2493 Decl *decl = static_cast<Decl*>(D); 2494 FunctionDecl *FD = cast<FunctionDecl>(decl); 2495 2496 ActiveScope = FnBodyScope; 2497 2498 // See if this is a redefinition. 2499 const FunctionDecl *Definition; 2500 if (FD->getBody(Definition)) { 2501 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2502 Diag(Definition->getLocation(), diag::note_previous_definition); 2503 } 2504 2505 // Builtin functions cannot be defined. 2506 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2507 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2508 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2509 FD->setInvalidDecl(); 2510 } 2511 } 2512 2513 // The return type of a function definition must be complete 2514 // (C99 6.9.1p3) 2515 if (FD->getResultType()->isIncompleteType() && 2516 !FD->getResultType()->isVoidType()) { 2517 Diag(FD->getLocation(), diag::err_func_def_incomplete_result) << FD; 2518 FD->setInvalidDecl(); 2519 } 2520 2521 PushDeclContext(FnBodyScope, FD); 2522 2523 // Check the validity of our function parameters 2524 CheckParmsForFunctionDef(FD); 2525 2526 // Introduce our parameters into the function scope 2527 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2528 ParmVarDecl *Param = FD->getParamDecl(p); 2529 Param->setOwningFunction(FD); 2530 2531 // If this has an identifier, add it to the scope stack. 2532 if (Param->getIdentifier()) 2533 PushOnScopeChains(Param, FnBodyScope); 2534 } 2535 2536 // Checking attributes of current function definition 2537 // dllimport attribute. 2538 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2539 // dllimport attribute cannot be applied to definition. 2540 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2541 Diag(FD->getLocation(), 2542 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2543 << "dllimport"; 2544 FD->setInvalidDecl(); 2545 return FD; 2546 } else { 2547 // If a symbol previously declared dllimport is later defined, the 2548 // attribute is ignored in subsequent references, and a warning is 2549 // emitted. 2550 Diag(FD->getLocation(), 2551 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2552 << FD->getNameAsCString() << "dllimport"; 2553 } 2554 } 2555 return FD; 2556} 2557 2558static bool StatementCreatesScope(Stmt* S) { 2559 bool result = false; 2560 if (DeclStmt* DS = dyn_cast<DeclStmt>(S)) { 2561 for (DeclStmt::decl_iterator i = DS->decl_begin(); 2562 i != DS->decl_end(); ++i) { 2563 if (VarDecl* D = dyn_cast<VarDecl>(*i)) { 2564 result |= D->getType()->isVariablyModifiedType(); 2565 result |= !!D->getAttr<CleanupAttr>(); 2566 } else if (TypedefDecl* D = dyn_cast<TypedefDecl>(*i)) { 2567 result |= D->getUnderlyingType()->isVariablyModifiedType(); 2568 } 2569 } 2570 } 2571 2572 return result; 2573} 2574 2575void Sema::RecursiveCalcLabelScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2576 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2577 std::vector<void*>& ScopeStack, 2578 Stmt* CurStmt, 2579 Stmt* ParentCompoundStmt) { 2580 for (Stmt::child_iterator i = CurStmt->child_begin(); 2581 i != CurStmt->child_end(); ++i) { 2582 if (!*i) continue; 2583 if (StatementCreatesScope(*i)) { 2584 ScopeStack.push_back(*i); 2585 PopScopeMap[*i] = ParentCompoundStmt; 2586 } else if (isa<LabelStmt>(CurStmt)) { 2587 LabelScopeMap[CurStmt] = ScopeStack.size() ? ScopeStack.back() : 0; 2588 } 2589 if (isa<DeclStmt>(*i)) continue; 2590 Stmt* CurCompound = isa<CompoundStmt>(*i) ? *i : ParentCompoundStmt; 2591 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, 2592 *i, CurCompound); 2593 } 2594 2595 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2596 ScopeStack.pop_back(); 2597 } 2598} 2599 2600void Sema::RecursiveCalcJumpScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2601 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2602 llvm::DenseMap<Stmt*, void*>& GotoScopeMap, 2603 std::vector<void*>& ScopeStack, 2604 Stmt* CurStmt) { 2605 for (Stmt::child_iterator i = CurStmt->child_begin(); 2606 i != CurStmt->child_end(); ++i) { 2607 if (!*i) continue; 2608 if (StatementCreatesScope(*i)) { 2609 ScopeStack.push_back(*i); 2610 } else if (GotoStmt* GS = dyn_cast<GotoStmt>(*i)) { 2611 void* LScope = LabelScopeMap[GS->getLabel()]; 2612 if (LScope) { 2613 bool foundScopeInStack = false; 2614 for (unsigned i = ScopeStack.size(); i > 0; --i) { 2615 if (LScope == ScopeStack[i-1]) { 2616 foundScopeInStack = true; 2617 break; 2618 } 2619 } 2620 if (!foundScopeInStack) { 2621 Diag(GS->getSourceRange().getBegin(), diag::err_goto_into_scope); 2622 } 2623 } 2624 } 2625 if (isa<DeclStmt>(*i)) continue; 2626 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, 2627 ScopeStack, *i); 2628 } 2629 2630 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2631 ScopeStack.pop_back(); 2632 } 2633} 2634 2635Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2636 Decl *dcl = static_cast<Decl *>(D); 2637 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2638 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2639 FD->setBody(Body); 2640 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2641 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2642 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2643 MD->setBody((Stmt*)Body); 2644 } else { 2645 Body->Destroy(Context); 2646 return 0; 2647 } 2648 PopDeclContext(); 2649 2650 // FIXME: Temporary hack to workaround nested C++ functions. For example: 2651 // class C2 { 2652 // void f() { 2653 // class LC1 { 2654 // int m() { return 1; } 2655 // }; 2656 // } 2657 // }; 2658 if (ActiveScope == 0) 2659 return D; 2660 2661 // Verify and clean out per-function state. 2662 2663 bool HaveLabels = !ActiveScope->LabelMap.empty(); 2664 // Check goto/label use. 2665 for (Scope::LabelMapTy::iterator I = ActiveScope->LabelMap.begin(), 2666 E = ActiveScope->LabelMap.end(); I != E; ++I) { 2667 // Verify that we have no forward references left. If so, there was a goto 2668 // or address of a label taken, but no definition of it. Label fwd 2669 // definitions are indicated with a null substmt. 2670 LabelStmt *L = static_cast<LabelStmt*>(I->second); 2671 if (L->getSubStmt() == 0) { 2672 // Emit error. 2673 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2674 2675 // At this point, we have gotos that use the bogus label. Stitch it into 2676 // the function body so that they aren't leaked and that the AST is well 2677 // formed. 2678 if (Body) { 2679#if 0 2680 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2681 // and the AST is malformed anyway. We should just blow away 'L'. 2682 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2683 cast<CompoundStmt>(Body)->push_back(L); 2684#else 2685 L->Destroy(Context); 2686#endif 2687 } else { 2688 // The whole function wasn't parsed correctly, just delete this. 2689 L->Destroy(Context); 2690 } 2691 } 2692 } 2693 // This reset is for both functions and methods. 2694 ActiveScope = 0; 2695 2696 if (!Body) return D; 2697 2698 if (HaveLabels) { 2699 llvm::DenseMap<Stmt*, void*> LabelScopeMap; 2700 llvm::DenseMap<void*, Stmt*> PopScopeMap; 2701 llvm::DenseMap<Stmt*, void*> GotoScopeMap; 2702 std::vector<void*> ScopeStack; 2703 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, Body, Body); 2704 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, ScopeStack, Body); 2705 } 2706 2707 return D; 2708} 2709 2710/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2711/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2712NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2713 IdentifierInfo &II, Scope *S) { 2714 // Before we produce a declaration for an implicitly defined 2715 // function, see whether there was a locally-scoped declaration of 2716 // this name as a function or variable. If so, use that 2717 // (non-visible) declaration, and complain about it. 2718 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2719 = LocallyScopedExternalDecls.find(&II); 2720 if (Pos != LocallyScopedExternalDecls.end()) { 2721 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 2722 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 2723 return Pos->second; 2724 } 2725 2726 // Extension in C99. Legal in C90, but warn about it. 2727 if (getLangOptions().C99) 2728 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2729 else 2730 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2731 2732 // FIXME: handle stuff like: 2733 // void foo() { extern float X(); } 2734 // void bar() { X(); } <-- implicit decl for X in another scope. 2735 2736 // Set a Declarator for the implicit definition: int foo(); 2737 const char *Dummy; 2738 DeclSpec DS; 2739 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2740 Error = Error; // Silence warning. 2741 assert(!Error && "Error setting up implicit decl!"); 2742 Declarator D(DS, Declarator::BlockContext); 2743 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 2744 0, 0, 0, Loc, D), 2745 SourceLocation()); 2746 D.SetIdentifier(&II, Loc); 2747 2748 // Insert this function into translation-unit scope. 2749 2750 DeclContext *PrevDC = CurContext; 2751 CurContext = Context.getTranslationUnitDecl(); 2752 2753 FunctionDecl *FD = 2754 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2755 FD->setImplicit(); 2756 2757 CurContext = PrevDC; 2758 2759 AddKnownFunctionAttributes(FD); 2760 2761 return FD; 2762} 2763 2764/// \brief Adds any function attributes that we know a priori based on 2765/// the declaration of this function. 2766/// 2767/// These attributes can apply both to implicitly-declared builtins 2768/// (like __builtin___printf_chk) or to library-declared functions 2769/// like NSLog or printf. 2770void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 2771 if (FD->isInvalidDecl()) 2772 return; 2773 2774 // If this is a built-in function, map its builtin attributes to 2775 // actual attributes. 2776 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2777 // Handle printf-formatting attributes. 2778 unsigned FormatIdx; 2779 bool HasVAListArg; 2780 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 2781 if (!FD->getAttr<FormatAttr>()) 2782 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 2783 FormatIdx + 2)); 2784 } 2785 2786 // Mark const if we don't care about errno and that is the only 2787 // thing preventing the function from being const. This allows 2788 // IRgen to use LLVM intrinsics for such functions. 2789 if (!getLangOptions().MathErrno && 2790 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 2791 if (!FD->getAttr<ConstAttr>()) 2792 FD->addAttr(::new (Context) ConstAttr()); 2793 } 2794 } 2795 2796 IdentifierInfo *Name = FD->getIdentifier(); 2797 if (!Name) 2798 return; 2799 if ((!getLangOptions().CPlusPlus && 2800 FD->getDeclContext()->isTranslationUnit()) || 2801 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 2802 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 2803 LinkageSpecDecl::lang_c)) { 2804 // Okay: this could be a libc/libm/Objective-C function we know 2805 // about. 2806 } else 2807 return; 2808 2809 unsigned KnownID; 2810 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 2811 if (KnownFunctionIDs[KnownID] == Name) 2812 break; 2813 2814 switch (KnownID) { 2815 case id_NSLog: 2816 case id_NSLogv: 2817 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 2818 // FIXME: We known better than our headers. 2819 const_cast<FormatAttr *>(Format)->setType("printf"); 2820 } else 2821 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 2822 break; 2823 2824 case id_asprintf: 2825 case id_vasprintf: 2826 if (!FD->getAttr<FormatAttr>()) 2827 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 2828 break; 2829 2830 default: 2831 // Unknown function or known function without any attributes to 2832 // add. Do nothing. 2833 break; 2834 } 2835} 2836 2837TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2838 Decl *LastDeclarator) { 2839 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2840 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2841 2842 // Scope manipulation handled by caller. 2843 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2844 D.getIdentifierLoc(), 2845 D.getIdentifier(), 2846 T); 2847 2848 if (TagType *TT = dyn_cast<TagType>(T)) { 2849 TagDecl *TD = TT->getDecl(); 2850 2851 // If the TagDecl that the TypedefDecl points to is an anonymous decl 2852 // keep track of the TypedefDecl. 2853 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 2854 TD->setTypedefForAnonDecl(NewTD); 2855 } 2856 2857 NewTD->setNextDeclarator(LastDeclarator); 2858 if (D.getInvalidType()) 2859 NewTD->setInvalidDecl(); 2860 return NewTD; 2861} 2862 2863/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2864/// former case, Name will be non-null. In the later case, Name will be null. 2865/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2866/// reference/declaration/definition of a tag. 2867Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2868 SourceLocation KWLoc, const CXXScopeSpec &SS, 2869 IdentifierInfo *Name, SourceLocation NameLoc, 2870 AttributeList *Attr) { 2871 // If this is not a definition, it must have a name. 2872 assert((Name != 0 || TK == TK_Definition) && 2873 "Nameless record must be a definition!"); 2874 2875 TagDecl::TagKind Kind; 2876 switch (TagSpec) { 2877 default: assert(0 && "Unknown tag type!"); 2878 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2879 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2880 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2881 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2882 } 2883 2884 DeclContext *SearchDC = CurContext; 2885 DeclContext *DC = CurContext; 2886 NamedDecl *PrevDecl = 0; 2887 2888 bool Invalid = false; 2889 2890 if (Name && SS.isNotEmpty()) { 2891 // We have a nested-name tag ('struct foo::bar'). 2892 2893 // Check for invalid 'foo::'. 2894 if (SS.isInvalid()) { 2895 Name = 0; 2896 goto CreateNewDecl; 2897 } 2898 2899 // FIXME: RequireCompleteDeclContext(SS)? 2900 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2901 SearchDC = DC; 2902 // Look-up name inside 'foo::'. 2903 PrevDecl = dyn_cast_or_null<TagDecl>( 2904 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 2905 2906 // A tag 'foo::bar' must already exist. 2907 if (PrevDecl == 0) { 2908 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2909 Name = 0; 2910 goto CreateNewDecl; 2911 } 2912 } else if (Name) { 2913 // If this is a named struct, check to see if there was a previous forward 2914 // declaration or definition. 2915 // FIXME: We're looking into outer scopes here, even when we 2916 // shouldn't be. Doing so can result in ambiguities that we 2917 // shouldn't be diagnosing. 2918 LookupResult R = LookupName(S, Name, LookupTagName, 2919 /*RedeclarationOnly=*/(TK != TK_Reference)); 2920 if (R.isAmbiguous()) { 2921 DiagnoseAmbiguousLookup(R, Name, NameLoc); 2922 // FIXME: This is not best way to recover from case like: 2923 // 2924 // struct S s; 2925 // 2926 // causes needless err_ovl_no_viable_function_in_init latter. 2927 Name = 0; 2928 PrevDecl = 0; 2929 Invalid = true; 2930 } 2931 else 2932 PrevDecl = R; 2933 2934 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2935 // FIXME: This makes sure that we ignore the contexts associated 2936 // with C structs, unions, and enums when looking for a matching 2937 // tag declaration or definition. See the similar lookup tweak 2938 // in Sema::LookupName; is there a better way to deal with this? 2939 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2940 SearchDC = SearchDC->getParent(); 2941 } 2942 } 2943 2944 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2945 // Maybe we will complain about the shadowed template parameter. 2946 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2947 // Just pretend that we didn't see the previous declaration. 2948 PrevDecl = 0; 2949 } 2950 2951 if (PrevDecl) { 2952 // Check whether the previous declaration is usable. 2953 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 2954 2955 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2956 // If this is a use of a previous tag, or if the tag is already declared 2957 // in the same scope (so that the definition/declaration completes or 2958 // rementions the tag), reuse the decl. 2959 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2960 // Make sure that this wasn't declared as an enum and now used as a 2961 // struct or something similar. 2962 if (PrevTagDecl->getTagKind() != Kind) { 2963 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2964 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2965 // Recover by making this an anonymous redefinition. 2966 Name = 0; 2967 PrevDecl = 0; 2968 Invalid = true; 2969 } else { 2970 // If this is a use, just return the declaration we found. 2971 2972 // FIXME: In the future, return a variant or some other clue 2973 // for the consumer of this Decl to know it doesn't own it. 2974 // For our current ASTs this shouldn't be a problem, but will 2975 // need to be changed with DeclGroups. 2976 if (TK == TK_Reference) 2977 return PrevDecl; 2978 2979 // Diagnose attempts to redefine a tag. 2980 if (TK == TK_Definition) { 2981 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2982 Diag(NameLoc, diag::err_redefinition) << Name; 2983 Diag(Def->getLocation(), diag::note_previous_definition); 2984 // If this is a redefinition, recover by making this 2985 // struct be anonymous, which will make any later 2986 // references get the previous definition. 2987 Name = 0; 2988 PrevDecl = 0; 2989 Invalid = true; 2990 } else { 2991 // If the type is currently being defined, complain 2992 // about a nested redefinition. 2993 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 2994 if (Tag->isBeingDefined()) { 2995 Diag(NameLoc, diag::err_nested_redefinition) << Name; 2996 Diag(PrevTagDecl->getLocation(), 2997 diag::note_previous_definition); 2998 Name = 0; 2999 PrevDecl = 0; 3000 Invalid = true; 3001 } 3002 } 3003 3004 // Okay, this is definition of a previously declared or referenced 3005 // tag PrevDecl. We're going to create a new Decl for it. 3006 } 3007 } 3008 // If we get here we have (another) forward declaration or we 3009 // have a definition. Just create a new decl. 3010 } else { 3011 // If we get here, this is a definition of a new tag type in a nested 3012 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3013 // new decl/type. We set PrevDecl to NULL so that the entities 3014 // have distinct types. 3015 PrevDecl = 0; 3016 } 3017 // If we get here, we're going to create a new Decl. If PrevDecl 3018 // is non-NULL, it's a definition of the tag declared by 3019 // PrevDecl. If it's NULL, we have a new definition. 3020 } else { 3021 // PrevDecl is a namespace, template, or anything else 3022 // that lives in the IDNS_Tag identifier namespace. 3023 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3024 // The tag name clashes with a namespace name, issue an error and 3025 // recover by making this tag be anonymous. 3026 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3027 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3028 Name = 0; 3029 PrevDecl = 0; 3030 Invalid = true; 3031 } else { 3032 // The existing declaration isn't relevant to us; we're in a 3033 // new scope, so clear out the previous declaration. 3034 PrevDecl = 0; 3035 } 3036 } 3037 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3038 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3039 // C.scope.pdecl]p5: 3040 // -- for an elaborated-type-specifier of the form 3041 // 3042 // class-key identifier 3043 // 3044 // if the elaborated-type-specifier is used in the 3045 // decl-specifier-seq or parameter-declaration-clause of a 3046 // function defined in namespace scope, the identifier is 3047 // declared as a class-name in the namespace that contains 3048 // the declaration; otherwise, except as a friend 3049 // declaration, the identifier is declared in the smallest 3050 // non-class, non-function-prototype scope that contains the 3051 // declaration. 3052 // 3053 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3054 // C structs and unions. 3055 // 3056 // GNU C also supports this behavior as part of its incomplete 3057 // enum types extension, while GNU C++ does not. 3058 // 3059 // Find the context where we'll be declaring the tag. 3060 // FIXME: We would like to maintain the current DeclContext as the 3061 // lexical context, 3062 while (SearchDC->isRecord()) 3063 SearchDC = SearchDC->getParent(); 3064 3065 // Find the scope where we'll be declaring the tag. 3066 while (S->isClassScope() || 3067 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3068 ((S->getFlags() & Scope::DeclScope) == 0) || 3069 (S->getEntity() && 3070 ((DeclContext *)S->getEntity())->isTransparentContext())) 3071 S = S->getParent(); 3072 } 3073 3074CreateNewDecl: 3075 3076 // If there is an identifier, use the location of the identifier as the 3077 // location of the decl, otherwise use the location of the struct/union 3078 // keyword. 3079 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3080 3081 // Otherwise, create a new declaration. If there is a previous 3082 // declaration of the same entity, the two will be linked via 3083 // PrevDecl. 3084 TagDecl *New; 3085 3086 if (Kind == TagDecl::TK_enum) { 3087 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3088 // enum X { A, B, C } D; D should chain to X. 3089 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3090 cast_or_null<EnumDecl>(PrevDecl)); 3091 // If this is an undefined enum, warn. 3092 if (TK != TK_Definition && !Invalid) { 3093 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3094 : diag::ext_forward_ref_enum; 3095 Diag(Loc, DK); 3096 } 3097 } else { 3098 // struct/union/class 3099 3100 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3101 // struct X { int A; } D; D should chain to X. 3102 if (getLangOptions().CPlusPlus) 3103 // FIXME: Look for a way to use RecordDecl for simple structs. 3104 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3105 cast_or_null<CXXRecordDecl>(PrevDecl)); 3106 else 3107 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3108 cast_or_null<RecordDecl>(PrevDecl)); 3109 } 3110 3111 if (Kind != TagDecl::TK_enum) { 3112 // Handle #pragma pack: if the #pragma pack stack has non-default 3113 // alignment, make up a packed attribute for this decl. These 3114 // attributes are checked when the ASTContext lays out the 3115 // structure. 3116 // 3117 // It is important for implementing the correct semantics that this 3118 // happen here (in act on tag decl). The #pragma pack stack is 3119 // maintained as a result of parser callbacks which can occur at 3120 // many points during the parsing of a struct declaration (because 3121 // the #pragma tokens are effectively skipped over during the 3122 // parsing of the struct). 3123 if (unsigned Alignment = getPragmaPackAlignment()) 3124 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3125 } 3126 3127 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3128 // C++ [dcl.typedef]p3: 3129 // [...] Similarly, in a given scope, a class or enumeration 3130 // shall not be declared with the same name as a typedef-name 3131 // that is declared in that scope and refers to a type other 3132 // than the class or enumeration itself. 3133 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3134 TypedefDecl *PrevTypedef = 0; 3135 if (Lookup.getKind() == LookupResult::Found) 3136 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3137 3138 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3139 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3140 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3141 Diag(Loc, diag::err_tag_definition_of_typedef) 3142 << Context.getTypeDeclType(New) 3143 << PrevTypedef->getUnderlyingType(); 3144 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3145 Invalid = true; 3146 } 3147 } 3148 3149 if (Invalid) 3150 New->setInvalidDecl(); 3151 3152 if (Attr) 3153 ProcessDeclAttributeList(New, Attr); 3154 3155 // If we're declaring or defining a tag in function prototype scope 3156 // in C, note that this type can only be used within the function. 3157 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3158 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3159 3160 // Set the lexical context. If the tag has a C++ scope specifier, the 3161 // lexical context will be different from the semantic context. 3162 New->setLexicalDeclContext(CurContext); 3163 3164 if (TK == TK_Definition) 3165 New->startDefinition(); 3166 3167 // If this has an identifier, add it to the scope stack. 3168 if (Name) { 3169 S = getNonFieldDeclScope(S); 3170 PushOnScopeChains(New, S); 3171 } else { 3172 CurContext->addDecl(New); 3173 } 3174 3175 return New; 3176} 3177 3178void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3179 AdjustDeclIfTemplate(TagD); 3180 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3181 3182 // Enter the tag context. 3183 PushDeclContext(S, Tag); 3184 3185 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3186 FieldCollector->StartClass(); 3187 3188 if (Record->getIdentifier()) { 3189 // C++ [class]p2: 3190 // [...] The class-name is also inserted into the scope of the 3191 // class itself; this is known as the injected-class-name. For 3192 // purposes of access checking, the injected-class-name is treated 3193 // as if it were a public member name. 3194 RecordDecl *InjectedClassName 3195 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3196 CurContext, Record->getLocation(), 3197 Record->getIdentifier(), Record); 3198 InjectedClassName->setImplicit(); 3199 PushOnScopeChains(InjectedClassName, S); 3200 } 3201 } 3202} 3203 3204void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3205 AdjustDeclIfTemplate(TagD); 3206 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3207 3208 if (isa<CXXRecordDecl>(Tag)) 3209 FieldCollector->FinishClass(); 3210 3211 // Exit this scope of this tag's definition. 3212 PopDeclContext(); 3213 3214 // Notify the consumer that we've defined a tag. 3215 Consumer.HandleTagDeclDefinition(Tag); 3216} 3217 3218bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3219 QualType FieldTy, const Expr *BitWidth) { 3220 // C99 6.7.2.1p4 - verify the field type. 3221 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3222 if (!FieldTy->isIntegralType()) { 3223 // Handle incomplete types with specific error. 3224 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3225 return true; 3226 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3227 << FieldName << BitWidth->getSourceRange(); 3228 } 3229 3230 llvm::APSInt Value; 3231 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3232 return true; 3233 3234 // Zero-width bitfield is ok for anonymous field. 3235 if (Value == 0 && FieldName) 3236 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3237 3238 if (Value.isNegative()) 3239 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3240 3241 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3242 // FIXME: We won't need the 0 size once we check that the field type is valid. 3243 if (TypeSize && Value.getZExtValue() > TypeSize) 3244 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3245 << FieldName << (unsigned)TypeSize; 3246 3247 return false; 3248} 3249 3250/// ActOnField - Each field of a struct/union/class is passed into this in order 3251/// to create a FieldDecl object for it. 3252Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3253 SourceLocation DeclStart, 3254 Declarator &D, ExprTy *BitfieldWidth) { 3255 return HandleField(S, static_cast<RecordDecl*>(TagD), DeclStart, D, 3256 static_cast<Expr*>(BitfieldWidth)); 3257} 3258 3259/// HandleField - Analyze a field of a C struct or a C++ data member. 3260/// 3261FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3262 SourceLocation DeclStart, 3263 Declarator &D, Expr *BitWidth) { 3264 IdentifierInfo *II = D.getIdentifier(); 3265 SourceLocation Loc = DeclStart; 3266 if (II) Loc = D.getIdentifierLoc(); 3267 3268 QualType T = GetTypeForDeclarator(D, S); 3269 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3270 bool InvalidDecl = false; 3271 3272 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3273 // than a variably modified type. 3274 if (T->isVariablyModifiedType()) { 3275 bool SizeIsNegative; 3276 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3277 SizeIsNegative); 3278 if (!FixedTy.isNull()) { 3279 Diag(Loc, diag::warn_illegal_constant_array_size); 3280 T = FixedTy; 3281 } else { 3282 if (SizeIsNegative) 3283 Diag(Loc, diag::err_typecheck_negative_array_size); 3284 else 3285 Diag(Loc, diag::err_typecheck_field_variable_size); 3286 T = Context.IntTy; 3287 InvalidDecl = true; 3288 } 3289 } 3290 3291 if (BitWidth) { 3292 if (VerifyBitField(Loc, II, T, BitWidth)) { 3293 InvalidDecl = true; 3294 DeleteExpr(BitWidth); 3295 BitWidth = 0; 3296 } 3297 } else { 3298 // Not a bitfield. 3299 3300 // validate II. 3301 3302 } 3303 3304 FieldDecl *NewFD = FieldDecl::Create(Context, Record, 3305 Loc, II, T, BitWidth, 3306 D.getDeclSpec().getStorageClassSpec() == 3307 DeclSpec::SCS_mutable); 3308 3309 if (II) { 3310 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3311 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3312 && !isa<TagDecl>(PrevDecl)) { 3313 Diag(Loc, diag::err_duplicate_member) << II; 3314 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3315 NewFD->setInvalidDecl(); 3316 Record->setInvalidDecl(); 3317 } 3318 } 3319 3320 if (getLangOptions().CPlusPlus) { 3321 CheckExtraCXXDefaultArguments(D); 3322 if (!T->isPODType()) 3323 cast<CXXRecordDecl>(Record)->setPOD(false); 3324 } 3325 3326 ProcessDeclAttributes(NewFD, D); 3327 if (T.isObjCGCWeak()) 3328 Diag(Loc, diag::warn_attribute_weak_on_field); 3329 3330 if (D.getInvalidType() || InvalidDecl) 3331 NewFD->setInvalidDecl(); 3332 3333 if (II) { 3334 PushOnScopeChains(NewFD, S); 3335 } else 3336 Record->addDecl(NewFD); 3337 3338 return NewFD; 3339} 3340 3341/// TranslateIvarVisibility - Translate visibility from a token ID to an 3342/// AST enum value. 3343static ObjCIvarDecl::AccessControl 3344TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3345 switch (ivarVisibility) { 3346 default: assert(0 && "Unknown visitibility kind"); 3347 case tok::objc_private: return ObjCIvarDecl::Private; 3348 case tok::objc_public: return ObjCIvarDecl::Public; 3349 case tok::objc_protected: return ObjCIvarDecl::Protected; 3350 case tok::objc_package: return ObjCIvarDecl::Package; 3351 } 3352} 3353 3354/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3355/// in order to create an IvarDecl object for it. 3356Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3357 SourceLocation DeclStart, 3358 Declarator &D, ExprTy *BitfieldWidth, 3359 tok::ObjCKeywordKind Visibility) { 3360 3361 IdentifierInfo *II = D.getIdentifier(); 3362 Expr *BitWidth = (Expr*)BitfieldWidth; 3363 SourceLocation Loc = DeclStart; 3364 if (II) Loc = D.getIdentifierLoc(); 3365 3366 // FIXME: Unnamed fields can be handled in various different ways, for 3367 // example, unnamed unions inject all members into the struct namespace! 3368 3369 QualType T = GetTypeForDeclarator(D, S); 3370 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3371 bool InvalidDecl = false; 3372 3373 if (BitWidth) { 3374 // 6.7.2.1p3, 6.7.2.1p4 3375 if (VerifyBitField(Loc, II, T, BitWidth)) { 3376 InvalidDecl = true; 3377 DeleteExpr(BitWidth); 3378 BitWidth = 0; 3379 } 3380 } else { 3381 // Not a bitfield. 3382 3383 // validate II. 3384 3385 } 3386 3387 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3388 // than a variably modified type. 3389 if (T->isVariablyModifiedType()) { 3390 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3391 InvalidDecl = true; 3392 } 3393 3394 // Get the visibility (access control) for this ivar. 3395 ObjCIvarDecl::AccessControl ac = 3396 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3397 : ObjCIvarDecl::None; 3398 3399 // Construct the decl. 3400 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3401 (Expr *)BitfieldWidth); 3402 3403 if (II) { 3404 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3405 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3406 && !isa<TagDecl>(PrevDecl)) { 3407 Diag(Loc, diag::err_duplicate_member) << II; 3408 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3409 NewID->setInvalidDecl(); 3410 } 3411 } 3412 3413 // Process attributes attached to the ivar. 3414 ProcessDeclAttributes(NewID, D); 3415 3416 if (D.getInvalidType() || InvalidDecl) 3417 NewID->setInvalidDecl(); 3418 3419 if (II) { 3420 // FIXME: When interfaces are DeclContexts, we'll need to add 3421 // these to the interface. 3422 S->AddDecl(NewID); 3423 IdResolver.AddDecl(NewID); 3424 } 3425 3426 return NewID; 3427} 3428 3429void Sema::ActOnFields(Scope* S, 3430 SourceLocation RecLoc, DeclTy *RecDecl, 3431 DeclTy **Fields, unsigned NumFields, 3432 SourceLocation LBrac, SourceLocation RBrac, 3433 AttributeList *Attr) { 3434 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3435 assert(EnclosingDecl && "missing record or interface decl"); 3436 3437 // If the decl this is being inserted into is invalid, then it may be a 3438 // redeclaration or some other bogus case. Don't try to add fields to it. 3439 if (EnclosingDecl->isInvalidDecl()) { 3440 // FIXME: Deallocate fields? 3441 return; 3442 } 3443 3444 3445 // Verify that all the fields are okay. 3446 unsigned NumNamedMembers = 0; 3447 llvm::SmallVector<FieldDecl*, 32> RecFields; 3448 3449 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3450 for (unsigned i = 0; i != NumFields; ++i) { 3451 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3452 assert(FD && "missing field decl"); 3453 3454 // Get the type for the field. 3455 Type *FDTy = FD->getType().getTypePtr(); 3456 3457 if (!FD->isAnonymousStructOrUnion()) { 3458 // Remember all fields written by the user. 3459 RecFields.push_back(FD); 3460 } 3461 3462 // If the field is already invalid for some reason, don't emit more 3463 // diagnostics about it. 3464 if (FD->isInvalidDecl()) 3465 continue; 3466 3467 // C99 6.7.2.1p2 - A field may not be a function type. 3468 if (FDTy->isFunctionType()) { 3469 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3470 << FD->getDeclName(); 3471 FD->setInvalidDecl(); 3472 EnclosingDecl->setInvalidDecl(); 3473 continue; 3474 } 3475 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3476 if (FDTy->isIncompleteType()) { 3477 if (!Record) { // Incomplete ivar type is always an error. 3478 RequireCompleteType(FD->getLocation(), FD->getType(), 3479 diag::err_field_incomplete); 3480 FD->setInvalidDecl(); 3481 EnclosingDecl->setInvalidDecl(); 3482 continue; 3483 } 3484 if (i != NumFields-1 || // ... that the last member ... 3485 !Record->isStruct() || // ... of a structure ... 3486 !FDTy->isArrayType()) { //... may have incomplete array type. 3487 RequireCompleteType(FD->getLocation(), FD->getType(), 3488 diag::err_field_incomplete); 3489 FD->setInvalidDecl(); 3490 EnclosingDecl->setInvalidDecl(); 3491 continue; 3492 } 3493 if (NumNamedMembers < 1) { //... must have more than named member ... 3494 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3495 << FD->getDeclName(); 3496 FD->setInvalidDecl(); 3497 EnclosingDecl->setInvalidDecl(); 3498 continue; 3499 } 3500 // Okay, we have a legal flexible array member at the end of the struct. 3501 if (Record) 3502 Record->setHasFlexibleArrayMember(true); 3503 } 3504 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3505 /// field of another structure or the element of an array. 3506 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3507 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3508 // If this is a member of a union, then entire union becomes "flexible". 3509 if (Record && Record->isUnion()) { 3510 Record->setHasFlexibleArrayMember(true); 3511 } else { 3512 // If this is a struct/class and this is not the last element, reject 3513 // it. Note that GCC supports variable sized arrays in the middle of 3514 // structures. 3515 if (i != NumFields-1) 3516 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3517 << FD->getDeclName(); 3518 else { 3519 // We support flexible arrays at the end of structs in 3520 // other structs as an extension. 3521 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3522 << FD->getDeclName(); 3523 if (Record) 3524 Record->setHasFlexibleArrayMember(true); 3525 } 3526 } 3527 } 3528 } 3529 /// A field cannot be an Objective-c object 3530 if (FDTy->isObjCInterfaceType()) { 3531 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3532 FD->setInvalidDecl(); 3533 EnclosingDecl->setInvalidDecl(); 3534 continue; 3535 } 3536 // Keep track of the number of named members. 3537 if (FD->getIdentifier()) 3538 ++NumNamedMembers; 3539 } 3540 3541 // Okay, we successfully defined 'Record'. 3542 if (Record) { 3543 Record->completeDefinition(Context); 3544 } else { 3545 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3546 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3547 ID->setIVarList(ClsFields, RecFields.size(), Context); 3548 ID->setLocEnd(RBrac); 3549 3550 // Must enforce the rule that ivars in the base classes may not be 3551 // duplicates. 3552 if (ID->getSuperClass()) { 3553 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3554 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3555 ObjCIvarDecl* Ivar = (*IVI); 3556 IdentifierInfo *II = Ivar->getIdentifier(); 3557 ObjCIvarDecl* prevIvar = 3558 ID->getSuperClass()->lookupInstanceVariable(II); 3559 if (prevIvar) { 3560 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3561 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3562 } 3563 } 3564 } 3565 } else if (ObjCImplementationDecl *IMPDecl = 3566 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3567 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3568 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3569 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3570 } 3571 } 3572 3573 if (Attr) 3574 ProcessDeclAttributeList(Record, Attr); 3575} 3576 3577Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3578 DeclTy *lastEnumConst, 3579 SourceLocation IdLoc, IdentifierInfo *Id, 3580 SourceLocation EqualLoc, ExprTy *val) { 3581 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3582 EnumConstantDecl *LastEnumConst = 3583 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3584 Expr *Val = static_cast<Expr*>(val); 3585 3586 // The scope passed in may not be a decl scope. Zip up the scope tree until 3587 // we find one that is. 3588 S = getNonFieldDeclScope(S); 3589 3590 // Verify that there isn't already something declared with this name in this 3591 // scope. 3592 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3593 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3594 // Maybe we will complain about the shadowed template parameter. 3595 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3596 // Just pretend that we didn't see the previous declaration. 3597 PrevDecl = 0; 3598 } 3599 3600 if (PrevDecl) { 3601 // When in C++, we may get a TagDecl with the same name; in this case the 3602 // enum constant will 'hide' the tag. 3603 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3604 "Received TagDecl when not in C++!"); 3605 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3606 if (isa<EnumConstantDecl>(PrevDecl)) 3607 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3608 else 3609 Diag(IdLoc, diag::err_redefinition) << Id; 3610 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3611 if (Val) Val->Destroy(Context); 3612 return 0; 3613 } 3614 } 3615 3616 llvm::APSInt EnumVal(32); 3617 QualType EltTy; 3618 if (Val) { 3619 // Make sure to promote the operand type to int. 3620 UsualUnaryConversions(Val); 3621 3622 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3623 SourceLocation ExpLoc; 3624 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3625 Val->Destroy(Context); 3626 Val = 0; // Just forget about it. 3627 } else { 3628 EltTy = Val->getType(); 3629 } 3630 } 3631 3632 if (!Val) { 3633 if (LastEnumConst) { 3634 // Assign the last value + 1. 3635 EnumVal = LastEnumConst->getInitVal(); 3636 ++EnumVal; 3637 3638 // Check for overflow on increment. 3639 if (EnumVal < LastEnumConst->getInitVal()) 3640 Diag(IdLoc, diag::warn_enum_value_overflow); 3641 3642 EltTy = LastEnumConst->getType(); 3643 } else { 3644 // First value, set to zero. 3645 EltTy = Context.IntTy; 3646 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3647 } 3648 } 3649 3650 EnumConstantDecl *New = 3651 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3652 Val, EnumVal); 3653 3654 // Register this decl in the current scope stack. 3655 PushOnScopeChains(New, S); 3656 3657 return New; 3658} 3659 3660// FIXME: For consistency with ActOnFields(), we should have the parser 3661// pass in the source location for the left/right braces. 3662void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3663 DeclTy **Elements, unsigned NumElements) { 3664 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3665 QualType EnumType = Context.getTypeDeclType(Enum); 3666 3667 // TODO: If the result value doesn't fit in an int, it must be a long or long 3668 // long value. ISO C does not support this, but GCC does as an extension, 3669 // emit a warning. 3670 unsigned IntWidth = Context.Target.getIntWidth(); 3671 3672 // Verify that all the values are okay, compute the size of the values, and 3673 // reverse the list. 3674 unsigned NumNegativeBits = 0; 3675 unsigned NumPositiveBits = 0; 3676 3677 // Keep track of whether all elements have type int. 3678 bool AllElementsInt = true; 3679 3680 for (unsigned i = 0; i != NumElements; ++i) { 3681 EnumConstantDecl *ECD = 3682 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3683 if (!ECD) continue; // Already issued a diagnostic. 3684 3685 // If the enum value doesn't fit in an int, emit an extension warning. 3686 const llvm::APSInt &InitVal = ECD->getInitVal(); 3687 assert(InitVal.getBitWidth() >= IntWidth && 3688 "Should have promoted value to int"); 3689 if (InitVal.getBitWidth() > IntWidth) { 3690 llvm::APSInt V(InitVal); 3691 V.trunc(IntWidth); 3692 V.extend(InitVal.getBitWidth()); 3693 if (V != InitVal) 3694 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3695 << InitVal.toString(10); 3696 } 3697 3698 // Keep track of the size of positive and negative values. 3699 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3700 NumPositiveBits = std::max(NumPositiveBits, 3701 (unsigned)InitVal.getActiveBits()); 3702 else 3703 NumNegativeBits = std::max(NumNegativeBits, 3704 (unsigned)InitVal.getMinSignedBits()); 3705 3706 // Keep track of whether every enum element has type int (very commmon). 3707 if (AllElementsInt) 3708 AllElementsInt = ECD->getType() == Context.IntTy; 3709 } 3710 3711 // Figure out the type that should be used for this enum. 3712 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3713 QualType BestType; 3714 unsigned BestWidth; 3715 3716 if (NumNegativeBits) { 3717 // If there is a negative value, figure out the smallest integer type (of 3718 // int/long/longlong) that fits. 3719 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3720 BestType = Context.IntTy; 3721 BestWidth = IntWidth; 3722 } else { 3723 BestWidth = Context.Target.getLongWidth(); 3724 3725 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3726 BestType = Context.LongTy; 3727 else { 3728 BestWidth = Context.Target.getLongLongWidth(); 3729 3730 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3731 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3732 BestType = Context.LongLongTy; 3733 } 3734 } 3735 } else { 3736 // If there is no negative value, figure out which of uint, ulong, ulonglong 3737 // fits. 3738 if (NumPositiveBits <= IntWidth) { 3739 BestType = Context.UnsignedIntTy; 3740 BestWidth = IntWidth; 3741 } else if (NumPositiveBits <= 3742 (BestWidth = Context.Target.getLongWidth())) { 3743 BestType = Context.UnsignedLongTy; 3744 } else { 3745 BestWidth = Context.Target.getLongLongWidth(); 3746 assert(NumPositiveBits <= BestWidth && 3747 "How could an initializer get larger than ULL?"); 3748 BestType = Context.UnsignedLongLongTy; 3749 } 3750 } 3751 3752 // Loop over all of the enumerator constants, changing their types to match 3753 // the type of the enum if needed. 3754 for (unsigned i = 0; i != NumElements; ++i) { 3755 EnumConstantDecl *ECD = 3756 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3757 if (!ECD) continue; // Already issued a diagnostic. 3758 3759 // Standard C says the enumerators have int type, but we allow, as an 3760 // extension, the enumerators to be larger than int size. If each 3761 // enumerator value fits in an int, type it as an int, otherwise type it the 3762 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3763 // that X has type 'int', not 'unsigned'. 3764 if (ECD->getType() == Context.IntTy) { 3765 // Make sure the init value is signed. 3766 llvm::APSInt IV = ECD->getInitVal(); 3767 IV.setIsSigned(true); 3768 ECD->setInitVal(IV); 3769 3770 if (getLangOptions().CPlusPlus) 3771 // C++ [dcl.enum]p4: Following the closing brace of an 3772 // enum-specifier, each enumerator has the type of its 3773 // enumeration. 3774 ECD->setType(EnumType); 3775 continue; // Already int type. 3776 } 3777 3778 // Determine whether the value fits into an int. 3779 llvm::APSInt InitVal = ECD->getInitVal(); 3780 bool FitsInInt; 3781 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3782 FitsInInt = InitVal.getActiveBits() < IntWidth; 3783 else 3784 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3785 3786 // If it fits into an integer type, force it. Otherwise force it to match 3787 // the enum decl type. 3788 QualType NewTy; 3789 unsigned NewWidth; 3790 bool NewSign; 3791 if (FitsInInt) { 3792 NewTy = Context.IntTy; 3793 NewWidth = IntWidth; 3794 NewSign = true; 3795 } else if (ECD->getType() == BestType) { 3796 // Already the right type! 3797 if (getLangOptions().CPlusPlus) 3798 // C++ [dcl.enum]p4: Following the closing brace of an 3799 // enum-specifier, each enumerator has the type of its 3800 // enumeration. 3801 ECD->setType(EnumType); 3802 continue; 3803 } else { 3804 NewTy = BestType; 3805 NewWidth = BestWidth; 3806 NewSign = BestType->isSignedIntegerType(); 3807 } 3808 3809 // Adjust the APSInt value. 3810 InitVal.extOrTrunc(NewWidth); 3811 InitVal.setIsSigned(NewSign); 3812 ECD->setInitVal(InitVal); 3813 3814 // Adjust the Expr initializer and type. 3815 if (ECD->getInitExpr()) 3816 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3817 /*isLvalue=*/false)); 3818 if (getLangOptions().CPlusPlus) 3819 // C++ [dcl.enum]p4: Following the closing brace of an 3820 // enum-specifier, each enumerator has the type of its 3821 // enumeration. 3822 ECD->setType(EnumType); 3823 else 3824 ECD->setType(NewTy); 3825 } 3826 3827 Enum->completeDefinition(Context, BestType); 3828} 3829 3830Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3831 ExprArg expr) { 3832 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3833 3834 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3835} 3836 3837