SemaDecl.cpp revision 4dd55f511d1fba732f2968f430ce999fc8293896
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 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1584 if (!DC->isRecord() && S->getFnParent() == 0) { 1585 // C99 6.9p2: The storage-class specifiers auto and register shall not 1586 // appear in the declaration specifiers in an external declaration. 1587 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1588 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1589 InvalidDecl = true; 1590 } 1591 } 1592 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1593 II, R, SC, 1594 // FIXME: Move to DeclGroup... 1595 D.getDeclSpec().getSourceRange().getBegin()); 1596 NewVD->setThreadSpecified(ThreadSpecified); 1597 NewVD->setNextDeclarator(LastDeclarator); 1598 1599 // Handle attributes prior to checking for duplicates in MergeVarDecl 1600 ProcessDeclAttributes(NewVD, D); 1601 1602 // Handle GNU asm-label extension (encoded as an attribute). 1603 if (Expr *E = (Expr*) D.getAsmLabel()) { 1604 // The parser guarantees this is a string. 1605 StringLiteral *SE = cast<StringLiteral>(E); 1606 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1607 SE->getByteLength()))); 1608 } 1609 1610 // Emit an error if an address space was applied to decl with local storage. 1611 // This includes arrays of objects with address space qualifiers, but not 1612 // automatic variables that point to other address spaces. 1613 // ISO/IEC TR 18037 S5.1.2 1614 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1615 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1616 InvalidDecl = true; 1617 } 1618 1619 if (NewVD->hasLocalStorage() && NewVD->getType().isObjCGCWeak()) { 1620 Diag(D.getIdentifierLoc(), diag::warn_attribute_weak_on_local); 1621 } 1622 1623 bool isIllegalVLA = R->isVariableArrayType() && NewVD->hasGlobalStorage(); 1624 bool isIllegalVM = R->isVariablyModifiedType() && NewVD->hasLinkage(); 1625 if (isIllegalVLA || isIllegalVM) { 1626 bool SizeIsNegative; 1627 QualType FixedTy = 1628 TryToFixInvalidVariablyModifiedType(R, Context, SizeIsNegative); 1629 if (!FixedTy.isNull()) { 1630 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1631 NewVD->setType(FixedTy); 1632 } else if (R->isVariableArrayType()) { 1633 NewVD->setInvalidDecl(); 1634 1635 const VariableArrayType *VAT = Context.getAsVariableArrayType(R); 1636 // FIXME: This won't give the correct result for 1637 // int a[10][n]; 1638 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1639 1640 if (NewVD->isFileVarDecl()) 1641 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1642 << SizeRange; 1643 else if (NewVD->getStorageClass() == VarDecl::Static) 1644 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1645 << SizeRange; 1646 else 1647 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1648 << SizeRange; 1649 } else { 1650 InvalidDecl = true; 1651 1652 if (NewVD->isFileVarDecl()) 1653 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1654 else 1655 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1656 } 1657 } 1658 1659 // If name lookup finds a previous declaration that is not in the 1660 // same scope as the new declaration, this may still be an 1661 // acceptable redeclaration. 1662 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1663 !(NewVD->hasLinkage() && 1664 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1665 PrevDecl = 0; 1666 1667 if (!PrevDecl && NewVD->isExternC(Context)) { 1668 // Since we did not find anything by this name and we're declaring 1669 // an extern "C" variable, look for a non-visible extern "C" 1670 // declaration with the same name. 1671 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1672 = LocallyScopedExternalDecls.find(Name); 1673 if (Pos != LocallyScopedExternalDecls.end()) 1674 PrevDecl = Pos->second; 1675 } 1676 1677 // Merge the decl with the existing one if appropriate. 1678 if (PrevDecl) { 1679 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1680 // The user tried to define a non-static data member 1681 // out-of-line (C++ [dcl.meaning]p1). 1682 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1683 << D.getCXXScopeSpec().getRange(); 1684 NewVD->Destroy(Context); 1685 return 0; 1686 } 1687 1688 Redeclaration = true; 1689 if (MergeVarDecl(NewVD, PrevDecl)) 1690 InvalidDecl = true; 1691 1692 if (D.getCXXScopeSpec().isSet()) { 1693 // No previous declaration in the qualifying scope. 1694 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1695 << Name << D.getCXXScopeSpec().getRange(); 1696 InvalidDecl = true; 1697 } 1698 } 1699 1700 if (!InvalidDecl && R->isVoidType() && !NewVD->hasExternalStorage()) { 1701 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1702 << R; 1703 InvalidDecl = true; 1704 } 1705 1706 1707 // If this is a locally-scoped extern C variable, update the map of 1708 // such variables. 1709 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1710 !InvalidDecl) 1711 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1712 1713 return NewVD; 1714} 1715 1716NamedDecl* 1717Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1718 QualType R, Decl *LastDeclarator, 1719 NamedDecl* PrevDecl, bool IsFunctionDefinition, 1720 bool& InvalidDecl, bool &Redeclaration) { 1721 assert(R.getTypePtr()->isFunctionType()); 1722 1723 DeclarationName Name = GetNameForDeclarator(D); 1724 FunctionDecl::StorageClass SC = FunctionDecl::None; 1725 switch (D.getDeclSpec().getStorageClassSpec()) { 1726 default: assert(0 && "Unknown storage class!"); 1727 case DeclSpec::SCS_auto: 1728 case DeclSpec::SCS_register: 1729 case DeclSpec::SCS_mutable: 1730 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1731 diag::err_typecheck_sclass_func); 1732 InvalidDecl = true; 1733 break; 1734 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1735 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1736 case DeclSpec::SCS_static: { 1737 if (DC->getLookupContext()->isFunctionOrMethod()) { 1738 // C99 6.7.1p5: 1739 // The declaration of an identifier for a function that has 1740 // block scope shall have no explicit storage-class specifier 1741 // other than extern 1742 // See also (C++ [dcl.stc]p4). 1743 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1744 diag::err_static_block_func); 1745 SC = FunctionDecl::None; 1746 } else 1747 SC = FunctionDecl::Static; 1748 break; 1749 } 1750 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1751 } 1752 1753 bool isInline = D.getDeclSpec().isInlineSpecified(); 1754 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1755 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1756 1757 FunctionDecl *NewFD; 1758 if (D.getKind() == Declarator::DK_Constructor) { 1759 // This is a C++ constructor declaration. 1760 assert(DC->isRecord() && 1761 "Constructors can only be declared in a member context"); 1762 1763 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1764 1765 // Create the new declaration 1766 NewFD = CXXConstructorDecl::Create(Context, 1767 cast<CXXRecordDecl>(DC), 1768 D.getIdentifierLoc(), Name, R, 1769 isExplicit, isInline, 1770 /*isImplicitlyDeclared=*/false); 1771 1772 if (InvalidDecl) 1773 NewFD->setInvalidDecl(); 1774 } else if (D.getKind() == Declarator::DK_Destructor) { 1775 // This is a C++ destructor declaration. 1776 if (DC->isRecord()) { 1777 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1778 1779 NewFD = CXXDestructorDecl::Create(Context, 1780 cast<CXXRecordDecl>(DC), 1781 D.getIdentifierLoc(), Name, R, 1782 isInline, 1783 /*isImplicitlyDeclared=*/false); 1784 1785 if (InvalidDecl) 1786 NewFD->setInvalidDecl(); 1787 } else { 1788 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1789 1790 // Create a FunctionDecl to satisfy the function definition parsing 1791 // code path. 1792 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1793 Name, R, SC, isInline, 1794 /*hasPrototype=*/true, 1795 // FIXME: Move to DeclGroup... 1796 D.getDeclSpec().getSourceRange().getBegin()); 1797 InvalidDecl = true; 1798 NewFD->setInvalidDecl(); 1799 } 1800 } else if (D.getKind() == Declarator::DK_Conversion) { 1801 if (!DC->isRecord()) { 1802 Diag(D.getIdentifierLoc(), 1803 diag::err_conv_function_not_member); 1804 return 0; 1805 } else { 1806 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1807 1808 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1809 D.getIdentifierLoc(), Name, R, 1810 isInline, isExplicit); 1811 1812 if (InvalidDecl) 1813 NewFD->setInvalidDecl(); 1814 } 1815 } else if (DC->isRecord()) { 1816 // This is a C++ method declaration. 1817 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1818 D.getIdentifierLoc(), Name, R, 1819 (SC == FunctionDecl::Static), isInline); 1820 } else { 1821 NewFD = FunctionDecl::Create(Context, DC, 1822 D.getIdentifierLoc(), 1823 Name, R, SC, isInline, 1824 /*hasPrototype=*/ 1825 (getLangOptions().CPlusPlus || 1826 (D.getNumTypeObjects() && 1827 D.getTypeObject(0).Fun.hasPrototype)), 1828 // FIXME: Move to DeclGroup... 1829 D.getDeclSpec().getSourceRange().getBegin()); 1830 } 1831 NewFD->setNextDeclarator(LastDeclarator); 1832 1833 // Set the lexical context. If the declarator has a C++ 1834 // scope specifier, the lexical context will be different 1835 // from the semantic context. 1836 NewFD->setLexicalDeclContext(CurContext); 1837 1838 // Handle GNU asm-label extension (encoded as an attribute). 1839 if (Expr *E = (Expr*) D.getAsmLabel()) { 1840 // The parser guarantees this is a string. 1841 StringLiteral *SE = cast<StringLiteral>(E); 1842 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1843 SE->getByteLength()))); 1844 } 1845 1846 // Copy the parameter declarations from the declarator D to 1847 // the function declaration NewFD, if they are available. 1848 if (D.getNumTypeObjects() > 0) { 1849 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1850 1851 // Create Decl objects for each parameter, adding them to the 1852 // FunctionDecl. 1853 llvm::SmallVector<ParmVarDecl*, 16> Params; 1854 1855 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1856 // function that takes no arguments, not a function that takes a 1857 // single void argument. 1858 // We let through "const void" here because Sema::GetTypeForDeclarator 1859 // already checks for that case. 1860 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1861 FTI.ArgInfo[0].Param && 1862 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1863 // empty arg list, don't push any params. 1864 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1865 1866 // In C++, the empty parameter-type-list must be spelled "void"; a 1867 // typedef of void is not permitted. 1868 if (getLangOptions().CPlusPlus && 1869 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1870 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1871 } 1872 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1873 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1874 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1875 } 1876 1877 NewFD->setParams(Context, &Params[0], Params.size()); 1878 } else if (R->getAsTypedefType()) { 1879 // When we're declaring a function with a typedef, as in the 1880 // following example, we'll need to synthesize (unnamed) 1881 // parameters for use in the declaration. 1882 // 1883 // @code 1884 // typedef void fn(int); 1885 // fn f; 1886 // @endcode 1887 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 1888 if (!FT) { 1889 // This is a typedef of a function with no prototype, so we 1890 // don't need to do anything. 1891 } else if ((FT->getNumArgs() == 0) || 1892 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1893 FT->getArgType(0)->isVoidType())) { 1894 // This is a zero-argument function. We don't need to do anything. 1895 } else { 1896 // Synthesize a parameter for each argument type. 1897 llvm::SmallVector<ParmVarDecl*, 16> Params; 1898 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 1899 ArgType != FT->arg_type_end(); ++ArgType) { 1900 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 1901 SourceLocation(), 0, 1902 *ArgType, VarDecl::None, 1903 0); 1904 Param->setImplicit(); 1905 Params.push_back(Param); 1906 } 1907 1908 NewFD->setParams(Context, &Params[0], Params.size()); 1909 } 1910 } 1911 1912 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1913 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1914 else if (isa<CXXDestructorDecl>(NewFD)) { 1915 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1916 Record->setUserDeclaredDestructor(true); 1917 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1918 // user-defined destructor. 1919 Record->setPOD(false); 1920 } else if (CXXConversionDecl *Conversion = 1921 dyn_cast<CXXConversionDecl>(NewFD)) 1922 ActOnConversionDeclarator(Conversion); 1923 1924 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1925 if (NewFD->isOverloadedOperator() && 1926 CheckOverloadedOperatorDeclaration(NewFD)) 1927 NewFD->setInvalidDecl(); 1928 1929 // If name lookup finds a previous declaration that is not in the 1930 // same scope as the new declaration, this may still be an 1931 // acceptable redeclaration. 1932 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1933 !(NewFD->hasLinkage() && 1934 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1935 PrevDecl = 0; 1936 1937 if (!PrevDecl && NewFD->isExternC(Context)) { 1938 // Since we did not find anything by this name and we're declaring 1939 // an extern "C" function, look for a non-visible extern "C" 1940 // declaration with the same name. 1941 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1942 = LocallyScopedExternalDecls.find(Name); 1943 if (Pos != LocallyScopedExternalDecls.end()) 1944 PrevDecl = Pos->second; 1945 } 1946 1947 // Merge or overload the declaration with an existing declaration of 1948 // the same name, if appropriate. 1949 bool OverloadableAttrRequired = false; 1950 if (PrevDecl) { 1951 // Determine whether NewFD is an overload of PrevDecl or 1952 // a declaration that requires merging. If it's an overload, 1953 // there's no more work to do here; we'll just add the new 1954 // function to the scope. 1955 OverloadedFunctionDecl::function_iterator MatchedDecl; 1956 1957 if (!getLangOptions().CPlusPlus && 1958 AllowOverloadingOfFunction(PrevDecl, Context)) { 1959 OverloadableAttrRequired = true; 1960 1961 // Functions marked "overloadable" must have a prototype (that 1962 // we can't get through declaration merging). 1963 if (!R->getAsFunctionProtoType()) { 1964 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 1965 << NewFD; 1966 InvalidDecl = true; 1967 Redeclaration = true; 1968 1969 // Turn this into a variadic function with no parameters. 1970 R = Context.getFunctionType(R->getAsFunctionType()->getResultType(), 1971 0, 0, true, 0); 1972 NewFD->setType(R); 1973 } 1974 } 1975 1976 if (PrevDecl && 1977 (!AllowOverloadingOfFunction(PrevDecl, Context) || 1978 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 1979 Redeclaration = true; 1980 Decl *OldDecl = PrevDecl; 1981 1982 // If PrevDecl was an overloaded function, extract the 1983 // FunctionDecl that matched. 1984 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1985 OldDecl = *MatchedDecl; 1986 1987 // NewFD and PrevDecl represent declarations that need to be 1988 // merged. 1989 if (MergeFunctionDecl(NewFD, OldDecl)) 1990 InvalidDecl = true; 1991 1992 if (!InvalidDecl) { 1993 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1994 1995 // An out-of-line member function declaration must also be a 1996 // definition (C++ [dcl.meaning]p1). 1997 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1998 !InvalidDecl) { 1999 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2000 << D.getCXXScopeSpec().getRange(); 2001 NewFD->setInvalidDecl(); 2002 } 2003 } 2004 } 2005 } 2006 2007 if (D.getCXXScopeSpec().isSet() && 2008 (!PrevDecl || !Redeclaration)) { 2009 // The user tried to provide an out-of-line definition for a 2010 // function that is a member of a class or namespace, but there 2011 // was no such member function declared (C++ [class.mfct]p2, 2012 // C++ [namespace.memdef]p2). For example: 2013 // 2014 // class X { 2015 // void f() const; 2016 // }; 2017 // 2018 // void X::f() { } // ill-formed 2019 // 2020 // Complain about this problem, and attempt to suggest close 2021 // matches (e.g., those that differ only in cv-qualifiers and 2022 // whether the parameter types are references). 2023 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2024 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2025 InvalidDecl = true; 2026 2027 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2028 true); 2029 assert(!Prev.isAmbiguous() && 2030 "Cannot have an ambiguity in previous-declaration lookup"); 2031 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2032 Func != FuncEnd; ++Func) { 2033 if (isa<FunctionDecl>(*Func) && 2034 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2035 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2036 } 2037 2038 PrevDecl = 0; 2039 } 2040 2041 // Handle attributes. We need to have merged decls when handling attributes 2042 // (for example to check for conflicts, etc). 2043 ProcessDeclAttributes(NewFD, D); 2044 AddKnownFunctionAttributes(NewFD); 2045 2046 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2047 // If a function name is overloadable in C, then every function 2048 // with that name must be marked "overloadable". 2049 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2050 << Redeclaration << NewFD; 2051 if (PrevDecl) 2052 Diag(PrevDecl->getLocation(), 2053 diag::note_attribute_overloadable_prev_overload); 2054 NewFD->addAttr(::new (Context) OverloadableAttr()); 2055 } 2056 2057 if (getLangOptions().CPlusPlus) { 2058 // In C++, check default arguments now that we have merged decls. Unless 2059 // the lexical context is the class, because in this case this is done 2060 // during delayed parsing anyway. 2061 if (!CurContext->isRecord()) 2062 CheckCXXDefaultArguments(NewFD); 2063 2064 // An out-of-line member function declaration must also be a 2065 // definition (C++ [dcl.meaning]p1). 2066 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2067 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2068 << D.getCXXScopeSpec().getRange(); 2069 InvalidDecl = true; 2070 } 2071 } 2072 2073 // If this is a locally-scoped extern C function, update the 2074 // map of such names. 2075 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2076 && !InvalidDecl) 2077 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2078 2079 return NewFD; 2080} 2081 2082bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2083 // FIXME: Need strict checking. In C89, we need to check for 2084 // any assignment, increment, decrement, function-calls, or 2085 // commas outside of a sizeof. In C99, it's the same list, 2086 // except that the aforementioned are allowed in unevaluated 2087 // expressions. Everything else falls under the 2088 // "may accept other forms of constant expressions" exception. 2089 // (We never end up here for C++, so the constant expression 2090 // rules there don't matter.) 2091 if (Init->isConstantInitializer(Context)) 2092 return false; 2093 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2094 << Init->getSourceRange(); 2095 return true; 2096} 2097 2098void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2099 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2100} 2101 2102/// AddInitializerToDecl - Adds the initializer Init to the 2103/// declaration dcl. If DirectInit is true, this is C++ direct 2104/// initialization rather than copy initialization. 2105void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2106 Decl *RealDecl = static_cast<Decl *>(dcl); 2107 // If there is no declaration, there was an error parsing it. Just ignore 2108 // the initializer. 2109 if (RealDecl == 0) 2110 return; 2111 2112 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2113 if (!VDecl) { 2114 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2115 RealDecl->setInvalidDecl(); 2116 return; 2117 } 2118 2119 const VarDecl *Def = 0; 2120 if (VDecl->getDefinition(Def)) { 2121 Diag(VDecl->getLocation(), diag::err_redefinition) 2122 << VDecl->getDeclName(); 2123 Diag(Def->getLocation(), diag::note_previous_definition); 2124 VDecl->setInvalidDecl(); 2125 return; 2126 } 2127 2128 // Take ownership of the expression, now that we're sure we have somewhere 2129 // to put it. 2130 Expr *Init = static_cast<Expr *>(init.release()); 2131 assert(Init && "missing initializer"); 2132 2133 // Get the decls type and save a reference for later, since 2134 // CheckInitializerTypes may change it. 2135 QualType DclT = VDecl->getType(), SavT = DclT; 2136 if (VDecl->isBlockVarDecl()) { 2137 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2138 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2139 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2140 VDecl->setInvalidDecl(); 2141 } else if (!VDecl->isInvalidDecl()) { 2142 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2143 VDecl->getDeclName(), DirectInit)) 2144 VDecl->setInvalidDecl(); 2145 2146 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2147 // Don't check invalid declarations to avoid emitting useless diagnostics. 2148 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2149 if (SC == VarDecl::Static) // C99 6.7.8p4. 2150 CheckForConstantInitializer(Init, DclT); 2151 } 2152 } 2153 } else if (VDecl->isFileVarDecl()) { 2154 if (VDecl->getStorageClass() == VarDecl::Extern) 2155 Diag(VDecl->getLocation(), diag::warn_extern_init); 2156 if (!VDecl->isInvalidDecl()) 2157 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2158 VDecl->getDeclName(), DirectInit)) 2159 VDecl->setInvalidDecl(); 2160 2161 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2162 // Don't check invalid declarations to avoid emitting useless diagnostics. 2163 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2164 // C99 6.7.8p4. All file scoped initializers need to be constant. 2165 CheckForConstantInitializer(Init, DclT); 2166 } 2167 } 2168 // If the type changed, it means we had an incomplete type that was 2169 // completed by the initializer. For example: 2170 // int ary[] = { 1, 3, 5 }; 2171 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2172 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2173 VDecl->setType(DclT); 2174 Init->setType(DclT); 2175 } 2176 2177 // Attach the initializer to the decl. 2178 VDecl->setInit(Init); 2179 return; 2180} 2181 2182void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2183 Decl *RealDecl = static_cast<Decl *>(dcl); 2184 2185 // If there is no declaration, there was an error parsing it. Just ignore it. 2186 if (RealDecl == 0) 2187 return; 2188 2189 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2190 QualType Type = Var->getType(); 2191 // C++ [dcl.init.ref]p3: 2192 // The initializer can be omitted for a reference only in a 2193 // parameter declaration (8.3.5), in the declaration of a 2194 // function return type, in the declaration of a class member 2195 // within its class declaration (9.2), and where the extern 2196 // specifier is explicitly used. 2197 if (Type->isReferenceType() && 2198 Var->getStorageClass() != VarDecl::Extern && 2199 Var->getStorageClass() != VarDecl::PrivateExtern) { 2200 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2201 << Var->getDeclName() 2202 << SourceRange(Var->getLocation(), Var->getLocation()); 2203 Var->setInvalidDecl(); 2204 return; 2205 } 2206 2207 // C++ [dcl.init]p9: 2208 // 2209 // If no initializer is specified for an object, and the object 2210 // is of (possibly cv-qualified) non-POD class type (or array 2211 // thereof), the object shall be default-initialized; if the 2212 // object is of const-qualified type, the underlying class type 2213 // shall have a user-declared default constructor. 2214 if (getLangOptions().CPlusPlus) { 2215 QualType InitType = Type; 2216 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2217 InitType = Array->getElementType(); 2218 if (Var->getStorageClass() != VarDecl::Extern && 2219 Var->getStorageClass() != VarDecl::PrivateExtern && 2220 InitType->isRecordType()) { 2221 const CXXConstructorDecl *Constructor = 0; 2222 if (!RequireCompleteType(Var->getLocation(), InitType, 2223 diag::err_invalid_incomplete_type_use)) 2224 Constructor 2225 = PerformInitializationByConstructor(InitType, 0, 0, 2226 Var->getLocation(), 2227 SourceRange(Var->getLocation(), 2228 Var->getLocation()), 2229 Var->getDeclName(), 2230 IK_Default); 2231 if (!Constructor) 2232 Var->setInvalidDecl(); 2233 } 2234 } 2235 2236#if 0 2237 // FIXME: Temporarily disabled because we are not properly parsing 2238 // linkage specifications on declarations, e.g., 2239 // 2240 // extern "C" const CGPoint CGPointerZero; 2241 // 2242 // C++ [dcl.init]p9: 2243 // 2244 // If no initializer is specified for an object, and the 2245 // object is of (possibly cv-qualified) non-POD class type (or 2246 // array thereof), the object shall be default-initialized; if 2247 // the object is of const-qualified type, the underlying class 2248 // type shall have a user-declared default 2249 // constructor. Otherwise, if no initializer is specified for 2250 // an object, the object and its subobjects, if any, have an 2251 // indeterminate initial value; if the object or any of its 2252 // subobjects are of const-qualified type, the program is 2253 // ill-formed. 2254 // 2255 // This isn't technically an error in C, so we don't diagnose it. 2256 // 2257 // FIXME: Actually perform the POD/user-defined default 2258 // constructor check. 2259 if (getLangOptions().CPlusPlus && 2260 Context.getCanonicalType(Type).isConstQualified() && 2261 Var->getStorageClass() != VarDecl::Extern) 2262 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2263 << Var->getName() 2264 << SourceRange(Var->getLocation(), Var->getLocation()); 2265#endif 2266 } 2267} 2268 2269/// The declarators are chained together backwards, reverse the list. 2270Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2271 // Often we have single declarators, handle them quickly. 2272 Decl *Group = static_cast<Decl*>(group); 2273 if (Group == 0) 2274 return 0; 2275 2276 Decl *NewGroup = 0; 2277 if (Group->getNextDeclarator() == 0) 2278 NewGroup = Group; 2279 else { // reverse the list. 2280 while (Group) { 2281 Decl *Next = Group->getNextDeclarator(); 2282 Group->setNextDeclarator(NewGroup); 2283 NewGroup = Group; 2284 Group = Next; 2285 } 2286 } 2287 // Perform semantic analysis that depends on having fully processed both 2288 // the declarator and initializer. 2289 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2290 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2291 if (!IDecl) 2292 continue; 2293 QualType T = IDecl->getType(); 2294 2295 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2296 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2297 if (IDecl->isBlockVarDecl() && 2298 IDecl->getStorageClass() != VarDecl::Extern) { 2299 if (!IDecl->isInvalidDecl() && 2300 RequireCompleteType(IDecl->getLocation(), T, 2301 diag::err_typecheck_decl_incomplete_type)) 2302 IDecl->setInvalidDecl(); 2303 } 2304 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2305 // object that has file scope without an initializer, and without a 2306 // storage-class specifier or with the storage-class specifier "static", 2307 // constitutes a tentative definition. Note: A tentative definition with 2308 // external linkage is valid (C99 6.2.2p5). 2309 if (IDecl->isTentativeDefinition(Context)) { 2310 QualType CheckType = T; 2311 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2312 2313 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2314 if (ArrayT) { 2315 CheckType = ArrayT->getElementType(); 2316 DiagID = diag::err_illegal_decl_array_incomplete_type; 2317 } 2318 2319 if (IDecl->isInvalidDecl()) { 2320 // Do nothing with invalid declarations 2321 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2322 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2323 // C99 6.9.2p3: If the declaration of an identifier for an object is 2324 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2325 // declared type shall not be an incomplete type. 2326 IDecl->setInvalidDecl(); 2327 } 2328 } 2329 } 2330 return NewGroup; 2331} 2332 2333/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2334/// to introduce parameters into function prototype scope. 2335Sema::DeclTy * 2336Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2337 const DeclSpec &DS = D.getDeclSpec(); 2338 2339 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2340 VarDecl::StorageClass StorageClass = VarDecl::None; 2341 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2342 StorageClass = VarDecl::Register; 2343 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2344 Diag(DS.getStorageClassSpecLoc(), 2345 diag::err_invalid_storage_class_in_func_decl); 2346 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2347 } 2348 if (DS.isThreadSpecified()) { 2349 Diag(DS.getThreadSpecLoc(), 2350 diag::err_invalid_storage_class_in_func_decl); 2351 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2352 } 2353 2354 // Check that there are no default arguments inside the type of this 2355 // parameter (C++ only). 2356 if (getLangOptions().CPlusPlus) 2357 CheckExtraCXXDefaultArguments(D); 2358 2359 // In this context, we *do not* check D.getInvalidType(). If the declarator 2360 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2361 // though it will not reflect the user specified type. 2362 QualType parmDeclType = GetTypeForDeclarator(D, S); 2363 2364 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2365 2366 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2367 // Can this happen for params? We already checked that they don't conflict 2368 // among each other. Here they can only shadow globals, which is ok. 2369 IdentifierInfo *II = D.getIdentifier(); 2370 if (II) { 2371 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2372 if (PrevDecl->isTemplateParameter()) { 2373 // Maybe we will complain about the shadowed template parameter. 2374 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2375 // Just pretend that we didn't see the previous declaration. 2376 PrevDecl = 0; 2377 } else if (S->isDeclScope(PrevDecl)) { 2378 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2379 2380 // Recover by removing the name 2381 II = 0; 2382 D.SetIdentifier(0, D.getIdentifierLoc()); 2383 } 2384 } 2385 } 2386 2387 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2388 // Doing the promotion here has a win and a loss. The win is the type for 2389 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2390 // code generator). The loss is the orginal type isn't preserved. For example: 2391 // 2392 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2393 // int blockvardecl[5]; 2394 // sizeof(parmvardecl); // size == 4 2395 // sizeof(blockvardecl); // size == 20 2396 // } 2397 // 2398 // For expressions, all implicit conversions are captured using the 2399 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2400 // 2401 // FIXME: If a source translation tool needs to see the original type, then 2402 // we need to consider storing both types (in ParmVarDecl)... 2403 // 2404 if (parmDeclType->isArrayType()) { 2405 // int x[restrict 4] -> int *restrict 2406 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2407 } else if (parmDeclType->isFunctionType()) 2408 parmDeclType = Context.getPointerType(parmDeclType); 2409 2410 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2411 D.getIdentifierLoc(), II, 2412 parmDeclType, StorageClass, 2413 0); 2414 2415 if (D.getInvalidType()) 2416 New->setInvalidDecl(); 2417 2418 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2419 if (D.getCXXScopeSpec().isSet()) { 2420 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2421 << D.getCXXScopeSpec().getRange(); 2422 New->setInvalidDecl(); 2423 } 2424 // Parameter declarators cannot be interface types. All ObjC objects are 2425 // passed by reference. 2426 if (parmDeclType->isObjCInterfaceType()) { 2427 Diag(D.getIdentifierLoc(), diag::err_object_cannot_be_by_value) 2428 << "passed"; 2429 New->setInvalidDecl(); 2430 } 2431 2432 // Add the parameter declaration into this scope. 2433 S->AddDecl(New); 2434 if (II) 2435 IdResolver.AddDecl(New); 2436 2437 ProcessDeclAttributes(New, D); 2438 return New; 2439 2440} 2441 2442void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2443 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2444 "Not a function declarator!"); 2445 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2446 2447 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2448 // for a K&R function. 2449 if (!FTI.hasPrototype) { 2450 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2451 if (FTI.ArgInfo[i].Param == 0) { 2452 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2453 << FTI.ArgInfo[i].Ident; 2454 // Implicitly declare the argument as type 'int' for lack of a better 2455 // type. 2456 DeclSpec DS; 2457 const char* PrevSpec; // unused 2458 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2459 PrevSpec); 2460 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2461 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2462 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2463 } 2464 } 2465 } 2466} 2467 2468Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2469 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2470 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2471 "Not a function declarator!"); 2472 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2473 2474 if (FTI.hasPrototype) { 2475 // FIXME: Diagnose arguments without names in C. 2476 } 2477 2478 Scope *ParentScope = FnBodyScope->getParent(); 2479 2480 return ActOnStartOfFunctionDef(FnBodyScope, 2481 ActOnDeclarator(ParentScope, D, 0, 2482 /*IsFunctionDefinition=*/true)); 2483} 2484 2485Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2486 Decl *decl = static_cast<Decl*>(D); 2487 FunctionDecl *FD = cast<FunctionDecl>(decl); 2488 2489 ActiveScope = FnBodyScope; 2490 2491 // See if this is a redefinition. 2492 const FunctionDecl *Definition; 2493 if (FD->getBody(Definition)) { 2494 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2495 Diag(Definition->getLocation(), diag::note_previous_definition); 2496 } 2497 2498 // Builtin functions cannot be defined. 2499 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2500 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2501 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2502 FD->setInvalidDecl(); 2503 } 2504 } 2505 2506 // The return type of a function definition must be complete 2507 // (C99 6.9.1p3) 2508 if (FD->getResultType()->isIncompleteType() && 2509 !FD->getResultType()->isVoidType()) { 2510 Diag(FD->getLocation(), diag::err_func_def_incomplete_result) << FD; 2511 FD->setInvalidDecl(); 2512 } 2513 2514 PushDeclContext(FnBodyScope, FD); 2515 2516 // Check the validity of our function parameters 2517 CheckParmsForFunctionDef(FD); 2518 2519 // Introduce our parameters into the function scope 2520 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2521 ParmVarDecl *Param = FD->getParamDecl(p); 2522 Param->setOwningFunction(FD); 2523 2524 // If this has an identifier, add it to the scope stack. 2525 if (Param->getIdentifier()) 2526 PushOnScopeChains(Param, FnBodyScope); 2527 } 2528 2529 // Checking attributes of current function definition 2530 // dllimport attribute. 2531 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2532 // dllimport attribute cannot be applied to definition. 2533 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2534 Diag(FD->getLocation(), 2535 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2536 << "dllimport"; 2537 FD->setInvalidDecl(); 2538 return FD; 2539 } else { 2540 // If a symbol previously declared dllimport is later defined, the 2541 // attribute is ignored in subsequent references, and a warning is 2542 // emitted. 2543 Diag(FD->getLocation(), 2544 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2545 << FD->getNameAsCString() << "dllimport"; 2546 } 2547 } 2548 return FD; 2549} 2550 2551static bool StatementCreatesScope(Stmt* S) { 2552 bool result = false; 2553 if (DeclStmt* DS = dyn_cast<DeclStmt>(S)) { 2554 for (DeclStmt::decl_iterator i = DS->decl_begin(); 2555 i != DS->decl_end(); ++i) { 2556 if (VarDecl* D = dyn_cast<VarDecl>(*i)) { 2557 result |= D->getType()->isVariablyModifiedType(); 2558 result |= !!D->getAttr<CleanupAttr>(); 2559 } else if (TypedefDecl* D = dyn_cast<TypedefDecl>(*i)) { 2560 result |= D->getUnderlyingType()->isVariablyModifiedType(); 2561 } 2562 } 2563 } 2564 2565 return result; 2566} 2567 2568void Sema::RecursiveCalcLabelScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2569 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2570 std::vector<void*>& ScopeStack, 2571 Stmt* CurStmt, 2572 Stmt* ParentCompoundStmt) { 2573 for (Stmt::child_iterator i = CurStmt->child_begin(); 2574 i != CurStmt->child_end(); ++i) { 2575 if (!*i) continue; 2576 if (StatementCreatesScope(*i)) { 2577 ScopeStack.push_back(*i); 2578 PopScopeMap[*i] = ParentCompoundStmt; 2579 } else if (isa<LabelStmt>(CurStmt)) { 2580 LabelScopeMap[CurStmt] = ScopeStack.size() ? ScopeStack.back() : 0; 2581 } 2582 if (isa<DeclStmt>(*i)) continue; 2583 Stmt* CurCompound = isa<CompoundStmt>(*i) ? *i : ParentCompoundStmt; 2584 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, 2585 *i, CurCompound); 2586 } 2587 2588 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2589 ScopeStack.pop_back(); 2590 } 2591} 2592 2593void Sema::RecursiveCalcJumpScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2594 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2595 llvm::DenseMap<Stmt*, void*>& GotoScopeMap, 2596 std::vector<void*>& ScopeStack, 2597 Stmt* CurStmt) { 2598 for (Stmt::child_iterator i = CurStmt->child_begin(); 2599 i != CurStmt->child_end(); ++i) { 2600 if (!*i) continue; 2601 if (StatementCreatesScope(*i)) { 2602 ScopeStack.push_back(*i); 2603 } else if (GotoStmt* GS = dyn_cast<GotoStmt>(*i)) { 2604 void* LScope = LabelScopeMap[GS->getLabel()]; 2605 if (LScope) { 2606 bool foundScopeInStack = false; 2607 for (unsigned i = ScopeStack.size(); i > 0; --i) { 2608 if (LScope == ScopeStack[i-1]) { 2609 foundScopeInStack = true; 2610 break; 2611 } 2612 } 2613 if (!foundScopeInStack) { 2614 Diag(GS->getSourceRange().getBegin(), diag::err_goto_into_scope); 2615 } 2616 } 2617 } 2618 if (isa<DeclStmt>(*i)) continue; 2619 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, 2620 ScopeStack, *i); 2621 } 2622 2623 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2624 ScopeStack.pop_back(); 2625 } 2626} 2627 2628Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2629 Decl *dcl = static_cast<Decl *>(D); 2630 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2631 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2632 FD->setBody(Body); 2633 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2634 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2635 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2636 MD->setBody((Stmt*)Body); 2637 } else { 2638 Body->Destroy(Context); 2639 return 0; 2640 } 2641 PopDeclContext(); 2642 2643 // FIXME: Temporary hack to workaround nested C++ functions. For example: 2644 // class C2 { 2645 // void f() { 2646 // class LC1 { 2647 // int m() { return 1; } 2648 // }; 2649 // } 2650 // }; 2651 if (ActiveScope == 0) 2652 return D; 2653 2654 // Verify and clean out per-function state. 2655 2656 bool HaveLabels = !ActiveScope->LabelMap.empty(); 2657 // Check goto/label use. 2658 for (Scope::LabelMapTy::iterator I = ActiveScope->LabelMap.begin(), 2659 E = ActiveScope->LabelMap.end(); I != E; ++I) { 2660 // Verify that we have no forward references left. If so, there was a goto 2661 // or address of a label taken, but no definition of it. Label fwd 2662 // definitions are indicated with a null substmt. 2663 LabelStmt *L = static_cast<LabelStmt*>(I->second); 2664 if (L->getSubStmt() == 0) { 2665 // Emit error. 2666 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2667 2668 // At this point, we have gotos that use the bogus label. Stitch it into 2669 // the function body so that they aren't leaked and that the AST is well 2670 // formed. 2671 if (Body) { 2672#if 0 2673 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2674 // and the AST is malformed anyway. We should just blow away 'L'. 2675 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2676 cast<CompoundStmt>(Body)->push_back(L); 2677#else 2678 L->Destroy(Context); 2679#endif 2680 } else { 2681 // The whole function wasn't parsed correctly, just delete this. 2682 L->Destroy(Context); 2683 } 2684 } 2685 } 2686 // This reset is for both functions and methods. 2687 ActiveScope = 0; 2688 2689 if (!Body) return D; 2690 2691 if (HaveLabels) { 2692 llvm::DenseMap<Stmt*, void*> LabelScopeMap; 2693 llvm::DenseMap<void*, Stmt*> PopScopeMap; 2694 llvm::DenseMap<Stmt*, void*> GotoScopeMap; 2695 std::vector<void*> ScopeStack; 2696 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, Body, Body); 2697 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, ScopeStack, Body); 2698 } 2699 2700 return D; 2701} 2702 2703/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2704/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2705NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2706 IdentifierInfo &II, Scope *S) { 2707 // Before we produce a declaration for an implicitly defined 2708 // function, see whether there was a locally-scoped declaration of 2709 // this name as a function or variable. If so, use that 2710 // (non-visible) declaration, and complain about it. 2711 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2712 = LocallyScopedExternalDecls.find(&II); 2713 if (Pos != LocallyScopedExternalDecls.end()) { 2714 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 2715 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 2716 return Pos->second; 2717 } 2718 2719 // Extension in C99. Legal in C90, but warn about it. 2720 if (getLangOptions().C99) 2721 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2722 else 2723 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2724 2725 // FIXME: handle stuff like: 2726 // void foo() { extern float X(); } 2727 // void bar() { X(); } <-- implicit decl for X in another scope. 2728 2729 // Set a Declarator for the implicit definition: int foo(); 2730 const char *Dummy; 2731 DeclSpec DS; 2732 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2733 Error = Error; // Silence warning. 2734 assert(!Error && "Error setting up implicit decl!"); 2735 Declarator D(DS, Declarator::BlockContext); 2736 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 2737 0, 0, 0, Loc, D), 2738 SourceLocation()); 2739 D.SetIdentifier(&II, Loc); 2740 2741 // Insert this function into translation-unit scope. 2742 2743 DeclContext *PrevDC = CurContext; 2744 CurContext = Context.getTranslationUnitDecl(); 2745 2746 FunctionDecl *FD = 2747 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2748 FD->setImplicit(); 2749 2750 CurContext = PrevDC; 2751 2752 AddKnownFunctionAttributes(FD); 2753 2754 return FD; 2755} 2756 2757/// \brief Adds any function attributes that we know a priori based on 2758/// the declaration of this function. 2759/// 2760/// These attributes can apply both to implicitly-declared builtins 2761/// (like __builtin___printf_chk) or to library-declared functions 2762/// like NSLog or printf. 2763void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 2764 if (FD->isInvalidDecl()) 2765 return; 2766 2767 // If this is a built-in function, map its builtin attributes to 2768 // actual attributes. 2769 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2770 // Handle printf-formatting attributes. 2771 unsigned FormatIdx; 2772 bool HasVAListArg; 2773 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 2774 if (!FD->getAttr<FormatAttr>()) 2775 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 2776 FormatIdx + 2)); 2777 } 2778 2779 // Mark const if we don't care about errno and that is the only 2780 // thing preventing the function from being const. This allows 2781 // IRgen to use LLVM intrinsics for such functions. 2782 if (!getLangOptions().MathErrno && 2783 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 2784 if (!FD->getAttr<ConstAttr>()) 2785 FD->addAttr(::new (Context) ConstAttr()); 2786 } 2787 } 2788 2789 IdentifierInfo *Name = FD->getIdentifier(); 2790 if (!Name) 2791 return; 2792 if ((!getLangOptions().CPlusPlus && 2793 FD->getDeclContext()->isTranslationUnit()) || 2794 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 2795 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 2796 LinkageSpecDecl::lang_c)) { 2797 // Okay: this could be a libc/libm/Objective-C function we know 2798 // about. 2799 } else 2800 return; 2801 2802 unsigned KnownID; 2803 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 2804 if (KnownFunctionIDs[KnownID] == Name) 2805 break; 2806 2807 switch (KnownID) { 2808 case id_NSLog: 2809 case id_NSLogv: 2810 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 2811 // FIXME: We known better than our headers. 2812 const_cast<FormatAttr *>(Format)->setType("printf"); 2813 } else 2814 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 2815 break; 2816 2817 case id_asprintf: 2818 case id_vasprintf: 2819 if (!FD->getAttr<FormatAttr>()) 2820 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 2821 break; 2822 2823 default: 2824 // Unknown function or known function without any attributes to 2825 // add. Do nothing. 2826 break; 2827 } 2828} 2829 2830TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2831 Decl *LastDeclarator) { 2832 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2833 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2834 2835 // Scope manipulation handled by caller. 2836 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2837 D.getIdentifierLoc(), 2838 D.getIdentifier(), 2839 T); 2840 2841 if (TagType *TT = dyn_cast<TagType>(T)) { 2842 TagDecl *TD = TT->getDecl(); 2843 2844 // If the TagDecl that the TypedefDecl points to is an anonymous decl 2845 // keep track of the TypedefDecl. 2846 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 2847 TD->setTypedefForAnonDecl(NewTD); 2848 } 2849 2850 NewTD->setNextDeclarator(LastDeclarator); 2851 if (D.getInvalidType()) 2852 NewTD->setInvalidDecl(); 2853 return NewTD; 2854} 2855 2856/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2857/// former case, Name will be non-null. In the later case, Name will be null. 2858/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2859/// reference/declaration/definition of a tag. 2860Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2861 SourceLocation KWLoc, const CXXScopeSpec &SS, 2862 IdentifierInfo *Name, SourceLocation NameLoc, 2863 AttributeList *Attr) { 2864 // If this is not a definition, it must have a name. 2865 assert((Name != 0 || TK == TK_Definition) && 2866 "Nameless record must be a definition!"); 2867 2868 TagDecl::TagKind Kind; 2869 switch (TagSpec) { 2870 default: assert(0 && "Unknown tag type!"); 2871 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2872 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2873 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2874 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2875 } 2876 2877 DeclContext *SearchDC = CurContext; 2878 DeclContext *DC = CurContext; 2879 NamedDecl *PrevDecl = 0; 2880 2881 bool Invalid = false; 2882 2883 if (Name && SS.isNotEmpty()) { 2884 // We have a nested-name tag ('struct foo::bar'). 2885 2886 // Check for invalid 'foo::'. 2887 if (SS.isInvalid()) { 2888 Name = 0; 2889 goto CreateNewDecl; 2890 } 2891 2892 // FIXME: RequireCompleteDeclContext(SS)? 2893 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2894 SearchDC = DC; 2895 // Look-up name inside 'foo::'. 2896 PrevDecl = dyn_cast_or_null<TagDecl>( 2897 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 2898 2899 // A tag 'foo::bar' must already exist. 2900 if (PrevDecl == 0) { 2901 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2902 Name = 0; 2903 goto CreateNewDecl; 2904 } 2905 } else if (Name) { 2906 // If this is a named struct, check to see if there was a previous forward 2907 // declaration or definition. 2908 // FIXME: We're looking into outer scopes here, even when we 2909 // shouldn't be. Doing so can result in ambiguities that we 2910 // shouldn't be diagnosing. 2911 LookupResult R = LookupName(S, Name, LookupTagName, 2912 /*RedeclarationOnly=*/(TK != TK_Reference)); 2913 if (R.isAmbiguous()) { 2914 DiagnoseAmbiguousLookup(R, Name, NameLoc); 2915 // FIXME: This is not best way to recover from case like: 2916 // 2917 // struct S s; 2918 // 2919 // causes needless err_ovl_no_viable_function_in_init latter. 2920 Name = 0; 2921 PrevDecl = 0; 2922 Invalid = true; 2923 } 2924 else 2925 PrevDecl = R; 2926 2927 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2928 // FIXME: This makes sure that we ignore the contexts associated 2929 // with C structs, unions, and enums when looking for a matching 2930 // tag declaration or definition. See the similar lookup tweak 2931 // in Sema::LookupName; is there a better way to deal with this? 2932 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2933 SearchDC = SearchDC->getParent(); 2934 } 2935 } 2936 2937 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2938 // Maybe we will complain about the shadowed template parameter. 2939 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2940 // Just pretend that we didn't see the previous declaration. 2941 PrevDecl = 0; 2942 } 2943 2944 if (PrevDecl) { 2945 // Check whether the previous declaration is usable. 2946 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 2947 2948 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2949 // If this is a use of a previous tag, or if the tag is already declared 2950 // in the same scope (so that the definition/declaration completes or 2951 // rementions the tag), reuse the decl. 2952 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2953 // Make sure that this wasn't declared as an enum and now used as a 2954 // struct or something similar. 2955 if (PrevTagDecl->getTagKind() != Kind) { 2956 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2957 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2958 // Recover by making this an anonymous redefinition. 2959 Name = 0; 2960 PrevDecl = 0; 2961 Invalid = true; 2962 } else { 2963 // If this is a use, just return the declaration we found. 2964 2965 // FIXME: In the future, return a variant or some other clue 2966 // for the consumer of this Decl to know it doesn't own it. 2967 // For our current ASTs this shouldn't be a problem, but will 2968 // need to be changed with DeclGroups. 2969 if (TK == TK_Reference) 2970 return PrevDecl; 2971 2972 // Diagnose attempts to redefine a tag. 2973 if (TK == TK_Definition) { 2974 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2975 Diag(NameLoc, diag::err_redefinition) << Name; 2976 Diag(Def->getLocation(), diag::note_previous_definition); 2977 // If this is a redefinition, recover by making this 2978 // struct be anonymous, which will make any later 2979 // references get the previous definition. 2980 Name = 0; 2981 PrevDecl = 0; 2982 Invalid = true; 2983 } else { 2984 // If the type is currently being defined, complain 2985 // about a nested redefinition. 2986 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 2987 if (Tag->isBeingDefined()) { 2988 Diag(NameLoc, diag::err_nested_redefinition) << Name; 2989 Diag(PrevTagDecl->getLocation(), 2990 diag::note_previous_definition); 2991 Name = 0; 2992 PrevDecl = 0; 2993 Invalid = true; 2994 } 2995 } 2996 2997 // Okay, this is definition of a previously declared or referenced 2998 // tag PrevDecl. We're going to create a new Decl for it. 2999 } 3000 } 3001 // If we get here we have (another) forward declaration or we 3002 // have a definition. Just create a new decl. 3003 } else { 3004 // If we get here, this is a definition of a new tag type in a nested 3005 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3006 // new decl/type. We set PrevDecl to NULL so that the entities 3007 // have distinct types. 3008 PrevDecl = 0; 3009 } 3010 // If we get here, we're going to create a new Decl. If PrevDecl 3011 // is non-NULL, it's a definition of the tag declared by 3012 // PrevDecl. If it's NULL, we have a new definition. 3013 } else { 3014 // PrevDecl is a namespace, template, or anything else 3015 // that lives in the IDNS_Tag identifier namespace. 3016 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3017 // The tag name clashes with a namespace name, issue an error and 3018 // recover by making this tag be anonymous. 3019 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3020 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3021 Name = 0; 3022 PrevDecl = 0; 3023 Invalid = true; 3024 } else { 3025 // The existing declaration isn't relevant to us; we're in a 3026 // new scope, so clear out the previous declaration. 3027 PrevDecl = 0; 3028 } 3029 } 3030 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3031 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3032 // C.scope.pdecl]p5: 3033 // -- for an elaborated-type-specifier of the form 3034 // 3035 // class-key identifier 3036 // 3037 // if the elaborated-type-specifier is used in the 3038 // decl-specifier-seq or parameter-declaration-clause of a 3039 // function defined in namespace scope, the identifier is 3040 // declared as a class-name in the namespace that contains 3041 // the declaration; otherwise, except as a friend 3042 // declaration, the identifier is declared in the smallest 3043 // non-class, non-function-prototype scope that contains the 3044 // declaration. 3045 // 3046 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3047 // C structs and unions. 3048 // 3049 // GNU C also supports this behavior as part of its incomplete 3050 // enum types extension, while GNU C++ does not. 3051 // 3052 // Find the context where we'll be declaring the tag. 3053 // FIXME: We would like to maintain the current DeclContext as the 3054 // lexical context, 3055 while (SearchDC->isRecord()) 3056 SearchDC = SearchDC->getParent(); 3057 3058 // Find the scope where we'll be declaring the tag. 3059 while (S->isClassScope() || 3060 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3061 ((S->getFlags() & Scope::DeclScope) == 0) || 3062 (S->getEntity() && 3063 ((DeclContext *)S->getEntity())->isTransparentContext())) 3064 S = S->getParent(); 3065 } 3066 3067CreateNewDecl: 3068 3069 // If there is an identifier, use the location of the identifier as the 3070 // location of the decl, otherwise use the location of the struct/union 3071 // keyword. 3072 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3073 3074 // Otherwise, create a new declaration. If there is a previous 3075 // declaration of the same entity, the two will be linked via 3076 // PrevDecl. 3077 TagDecl *New; 3078 3079 if (Kind == TagDecl::TK_enum) { 3080 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3081 // enum X { A, B, C } D; D should chain to X. 3082 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3083 cast_or_null<EnumDecl>(PrevDecl)); 3084 // If this is an undefined enum, warn. 3085 if (TK != TK_Definition && !Invalid) { 3086 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3087 : diag::ext_forward_ref_enum; 3088 Diag(Loc, DK); 3089 } 3090 } else { 3091 // struct/union/class 3092 3093 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3094 // struct X { int A; } D; D should chain to X. 3095 if (getLangOptions().CPlusPlus) 3096 // FIXME: Look for a way to use RecordDecl for simple structs. 3097 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3098 cast_or_null<CXXRecordDecl>(PrevDecl)); 3099 else 3100 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3101 cast_or_null<RecordDecl>(PrevDecl)); 3102 } 3103 3104 if (Kind != TagDecl::TK_enum) { 3105 // Handle #pragma pack: if the #pragma pack stack has non-default 3106 // alignment, make up a packed attribute for this decl. These 3107 // attributes are checked when the ASTContext lays out the 3108 // structure. 3109 // 3110 // It is important for implementing the correct semantics that this 3111 // happen here (in act on tag decl). The #pragma pack stack is 3112 // maintained as a result of parser callbacks which can occur at 3113 // many points during the parsing of a struct declaration (because 3114 // the #pragma tokens are effectively skipped over during the 3115 // parsing of the struct). 3116 if (unsigned Alignment = getPragmaPackAlignment()) 3117 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3118 } 3119 3120 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3121 // C++ [dcl.typedef]p3: 3122 // [...] Similarly, in a given scope, a class or enumeration 3123 // shall not be declared with the same name as a typedef-name 3124 // that is declared in that scope and refers to a type other 3125 // than the class or enumeration itself. 3126 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3127 TypedefDecl *PrevTypedef = 0; 3128 if (Lookup.getKind() == LookupResult::Found) 3129 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3130 3131 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3132 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3133 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3134 Diag(Loc, diag::err_tag_definition_of_typedef) 3135 << Context.getTypeDeclType(New) 3136 << PrevTypedef->getUnderlyingType(); 3137 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3138 Invalid = true; 3139 } 3140 } 3141 3142 if (Invalid) 3143 New->setInvalidDecl(); 3144 3145 if (Attr) 3146 ProcessDeclAttributeList(New, Attr); 3147 3148 // If we're declaring or defining a tag in function prototype scope 3149 // in C, note that this type can only be used within the function. 3150 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3151 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3152 3153 // Set the lexical context. If the tag has a C++ scope specifier, the 3154 // lexical context will be different from the semantic context. 3155 New->setLexicalDeclContext(CurContext); 3156 3157 if (TK == TK_Definition) 3158 New->startDefinition(); 3159 3160 // If this has an identifier, add it to the scope stack. 3161 if (Name) { 3162 S = getNonFieldDeclScope(S); 3163 PushOnScopeChains(New, S); 3164 } else { 3165 CurContext->addDecl(New); 3166 } 3167 3168 return New; 3169} 3170 3171void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3172 AdjustDeclIfTemplate(TagD); 3173 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3174 3175 // Enter the tag context. 3176 PushDeclContext(S, Tag); 3177 3178 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3179 FieldCollector->StartClass(); 3180 3181 if (Record->getIdentifier()) { 3182 // C++ [class]p2: 3183 // [...] The class-name is also inserted into the scope of the 3184 // class itself; this is known as the injected-class-name. For 3185 // purposes of access checking, the injected-class-name is treated 3186 // as if it were a public member name. 3187 RecordDecl *InjectedClassName 3188 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3189 CurContext, Record->getLocation(), 3190 Record->getIdentifier(), Record); 3191 InjectedClassName->setImplicit(); 3192 PushOnScopeChains(InjectedClassName, S); 3193 } 3194 } 3195} 3196 3197void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3198 AdjustDeclIfTemplate(TagD); 3199 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3200 3201 if (isa<CXXRecordDecl>(Tag)) 3202 FieldCollector->FinishClass(); 3203 3204 // Exit this scope of this tag's definition. 3205 PopDeclContext(); 3206 3207 // Notify the consumer that we've defined a tag. 3208 Consumer.HandleTagDeclDefinition(Tag); 3209} 3210 3211bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3212 QualType FieldTy, const Expr *BitWidth) { 3213 // C99 6.7.2.1p4 - verify the field type. 3214 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3215 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3216 // Handle incomplete types with specific error. 3217 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3218 return true; 3219 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3220 << FieldName << FieldTy << BitWidth->getSourceRange(); 3221 } 3222 3223 // If the bit-width is type- or value-dependent, don't try to check 3224 // it now. 3225 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3226 return false; 3227 3228 llvm::APSInt Value; 3229 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3230 return true; 3231 3232 // Zero-width bitfield is ok for anonymous field. 3233 if (Value == 0 && FieldName) 3234 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3235 3236 if (Value.isNegative()) 3237 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3238 3239 if (!FieldTy->isDependentType()) { 3240 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3241 // FIXME: We won't need the 0 size once we check that the field type is valid. 3242 if (TypeSize && Value.getZExtValue() > TypeSize) 3243 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3244 << FieldName << (unsigned)TypeSize; 3245 } 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 AS_public); 3258} 3259 3260/// HandleField - Analyze a field of a C struct or a C++ data member. 3261/// 3262FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3263 SourceLocation DeclStart, 3264 Declarator &D, Expr *BitWidth, 3265 AccessSpecifier AS) { 3266 IdentifierInfo *II = D.getIdentifier(); 3267 SourceLocation Loc = DeclStart; 3268 if (II) Loc = D.getIdentifierLoc(); 3269 3270 QualType T = GetTypeForDeclarator(D, S); 3271 3272 if (getLangOptions().CPlusPlus) 3273 CheckExtraCXXDefaultArguments(D); 3274 3275 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3276 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3277 PrevDecl = 0; 3278 3279 FieldDecl *NewFD 3280 = CheckFieldDecl(II, T, Record, Loc, 3281 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3282 BitWidth, AS, PrevDecl, &D); 3283 if (NewFD->isInvalidDecl() && PrevDecl) { 3284 // Don't introduce NewFD into scope; there's already something 3285 // with the same name in the same scope. 3286 } else if (II) { 3287 PushOnScopeChains(NewFD, S); 3288 } else 3289 Record->addDecl(NewFD); 3290 3291 return NewFD; 3292} 3293 3294/// \brief Build a new FieldDecl and check its well-formedness. 3295/// 3296/// This routine builds a new FieldDecl given the fields name, type, 3297/// record, etc. \p PrevDecl should refer to any previous declaration 3298/// with the same name and in the same scope as the field to be 3299/// created. 3300/// 3301/// \returns a new FieldDecl. 3302/// 3303/// \todo The Declarator argument is a hack. It will be removed once 3304FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3305 RecordDecl *Record, SourceLocation Loc, 3306 bool Mutable, Expr *BitWidth, 3307 AccessSpecifier AS, NamedDecl *PrevDecl, 3308 Declarator *D) { 3309 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3310 bool InvalidDecl = false; 3311 3312 // If we receive a broken type, recover by assuming 'int' and 3313 // marking this declaration as invalid. 3314 if (T.isNull()) { 3315 InvalidDecl = true; 3316 T = Context.IntTy; 3317 } 3318 3319 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3320 // than a variably modified type. 3321 if (T->isVariablyModifiedType()) { 3322 bool SizeIsNegative; 3323 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3324 SizeIsNegative); 3325 if (!FixedTy.isNull()) { 3326 Diag(Loc, diag::warn_illegal_constant_array_size); 3327 T = FixedTy; 3328 } else { 3329 if (SizeIsNegative) 3330 Diag(Loc, diag::err_typecheck_negative_array_size); 3331 else 3332 Diag(Loc, diag::err_typecheck_field_variable_size); 3333 T = Context.IntTy; 3334 InvalidDecl = true; 3335 } 3336 } 3337 3338 // If this is declared as a bit-field, check the bit-field. 3339 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3340 InvalidDecl = true; 3341 DeleteExpr(BitWidth); 3342 BitWidth = 0; 3343 } 3344 3345 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3346 Mutable); 3347 3348 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3349 Diag(Loc, diag::err_duplicate_member) << II; 3350 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3351 NewFD->setInvalidDecl(); 3352 Record->setInvalidDecl(); 3353 } 3354 3355 if (getLangOptions().CPlusPlus && !T->isPODType()) 3356 cast<CXXRecordDecl>(Record)->setPOD(false); 3357 3358 // FIXME: We need to pass in the attributes given an AST 3359 // representation, not a parser representation. 3360 if (D) 3361 ProcessDeclAttributes(NewFD, *D); 3362 3363 if (T.isObjCGCWeak()) 3364 Diag(Loc, diag::warn_attribute_weak_on_field); 3365 3366 if (InvalidDecl) 3367 NewFD->setInvalidDecl(); 3368 3369 NewFD->setAccess(AS); 3370 3371 // C++ [dcl.init.aggr]p1: 3372 // An aggregate is an array or a class (clause 9) with [...] no 3373 // private or protected non-static data members (clause 11). 3374 // A POD must be an aggregate. 3375 if (getLangOptions().CPlusPlus && 3376 (AS == AS_private || AS == AS_protected)) { 3377 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3378 CXXRecord->setAggregate(false); 3379 CXXRecord->setPOD(false); 3380 } 3381 3382 return NewFD; 3383} 3384 3385/// TranslateIvarVisibility - Translate visibility from a token ID to an 3386/// AST enum value. 3387static ObjCIvarDecl::AccessControl 3388TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3389 switch (ivarVisibility) { 3390 default: assert(0 && "Unknown visitibility kind"); 3391 case tok::objc_private: return ObjCIvarDecl::Private; 3392 case tok::objc_public: return ObjCIvarDecl::Public; 3393 case tok::objc_protected: return ObjCIvarDecl::Protected; 3394 case tok::objc_package: return ObjCIvarDecl::Package; 3395 } 3396} 3397 3398/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3399/// in order to create an IvarDecl object for it. 3400Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3401 SourceLocation DeclStart, 3402 Declarator &D, ExprTy *BitfieldWidth, 3403 tok::ObjCKeywordKind Visibility) { 3404 3405 IdentifierInfo *II = D.getIdentifier(); 3406 Expr *BitWidth = (Expr*)BitfieldWidth; 3407 SourceLocation Loc = DeclStart; 3408 if (II) Loc = D.getIdentifierLoc(); 3409 3410 // FIXME: Unnamed fields can be handled in various different ways, for 3411 // example, unnamed unions inject all members into the struct namespace! 3412 3413 QualType T = GetTypeForDeclarator(D, S); 3414 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3415 bool InvalidDecl = false; 3416 3417 if (BitWidth) { 3418 // 6.7.2.1p3, 6.7.2.1p4 3419 if (VerifyBitField(Loc, II, T, BitWidth)) { 3420 InvalidDecl = true; 3421 DeleteExpr(BitWidth); 3422 BitWidth = 0; 3423 } 3424 } else { 3425 // Not a bitfield. 3426 3427 // validate II. 3428 3429 } 3430 3431 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3432 // than a variably modified type. 3433 if (T->isVariablyModifiedType()) { 3434 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3435 InvalidDecl = true; 3436 } 3437 3438 // Get the visibility (access control) for this ivar. 3439 ObjCIvarDecl::AccessControl ac = 3440 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3441 : ObjCIvarDecl::None; 3442 3443 // Construct the decl. 3444 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3445 (Expr *)BitfieldWidth); 3446 3447 if (II) { 3448 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3449 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3450 && !isa<TagDecl>(PrevDecl)) { 3451 Diag(Loc, diag::err_duplicate_member) << II; 3452 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3453 NewID->setInvalidDecl(); 3454 } 3455 } 3456 3457 // Process attributes attached to the ivar. 3458 ProcessDeclAttributes(NewID, D); 3459 3460 if (D.getInvalidType() || InvalidDecl) 3461 NewID->setInvalidDecl(); 3462 3463 if (II) { 3464 // FIXME: When interfaces are DeclContexts, we'll need to add 3465 // these to the interface. 3466 S->AddDecl(NewID); 3467 IdResolver.AddDecl(NewID); 3468 } 3469 3470 return NewID; 3471} 3472 3473void Sema::ActOnFields(Scope* S, 3474 SourceLocation RecLoc, DeclTy *RecDecl, 3475 DeclTy **Fields, unsigned NumFields, 3476 SourceLocation LBrac, SourceLocation RBrac, 3477 AttributeList *Attr) { 3478 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3479 assert(EnclosingDecl && "missing record or interface decl"); 3480 3481 // If the decl this is being inserted into is invalid, then it may be a 3482 // redeclaration or some other bogus case. Don't try to add fields to it. 3483 if (EnclosingDecl->isInvalidDecl()) { 3484 // FIXME: Deallocate fields? 3485 return; 3486 } 3487 3488 3489 // Verify that all the fields are okay. 3490 unsigned NumNamedMembers = 0; 3491 llvm::SmallVector<FieldDecl*, 32> RecFields; 3492 3493 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3494 for (unsigned i = 0; i != NumFields; ++i) { 3495 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3496 assert(FD && "missing field decl"); 3497 3498 // Get the type for the field. 3499 Type *FDTy = FD->getType().getTypePtr(); 3500 3501 if (!FD->isAnonymousStructOrUnion()) { 3502 // Remember all fields written by the user. 3503 RecFields.push_back(FD); 3504 } 3505 3506 // If the field is already invalid for some reason, don't emit more 3507 // diagnostics about it. 3508 if (FD->isInvalidDecl()) 3509 continue; 3510 3511 // C99 6.7.2.1p2 - A field may not be a function type. 3512 if (FDTy->isFunctionType()) { 3513 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3514 << FD->getDeclName(); 3515 FD->setInvalidDecl(); 3516 EnclosingDecl->setInvalidDecl(); 3517 continue; 3518 } 3519 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3520 if (FDTy->isIncompleteType()) { 3521 if (!Record) { // Incomplete ivar type is always an error. 3522 RequireCompleteType(FD->getLocation(), FD->getType(), 3523 diag::err_field_incomplete); 3524 FD->setInvalidDecl(); 3525 EnclosingDecl->setInvalidDecl(); 3526 continue; 3527 } 3528 if (i != NumFields-1 || // ... that the last member ... 3529 !Record->isStruct() || // ... of a structure ... 3530 !FDTy->isArrayType()) { //... may have incomplete array type. 3531 RequireCompleteType(FD->getLocation(), FD->getType(), 3532 diag::err_field_incomplete); 3533 FD->setInvalidDecl(); 3534 EnclosingDecl->setInvalidDecl(); 3535 continue; 3536 } 3537 if (NumNamedMembers < 1) { //... must have more than named member ... 3538 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3539 << FD->getDeclName(); 3540 FD->setInvalidDecl(); 3541 EnclosingDecl->setInvalidDecl(); 3542 continue; 3543 } 3544 // Okay, we have a legal flexible array member at the end of the struct. 3545 if (Record) 3546 Record->setHasFlexibleArrayMember(true); 3547 } 3548 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3549 /// field of another structure or the element of an array. 3550 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3551 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3552 // If this is a member of a union, then entire union becomes "flexible". 3553 if (Record && Record->isUnion()) { 3554 Record->setHasFlexibleArrayMember(true); 3555 } else { 3556 // If this is a struct/class and this is not the last element, reject 3557 // it. Note that GCC supports variable sized arrays in the middle of 3558 // structures. 3559 if (i != NumFields-1) 3560 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3561 << FD->getDeclName(); 3562 else { 3563 // We support flexible arrays at the end of structs in 3564 // other structs as an extension. 3565 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3566 << FD->getDeclName(); 3567 if (Record) 3568 Record->setHasFlexibleArrayMember(true); 3569 } 3570 } 3571 } 3572 } 3573 /// A field cannot be an Objective-c object 3574 if (FDTy->isObjCInterfaceType()) { 3575 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3576 FD->setInvalidDecl(); 3577 EnclosingDecl->setInvalidDecl(); 3578 continue; 3579 } 3580 // Keep track of the number of named members. 3581 if (FD->getIdentifier()) 3582 ++NumNamedMembers; 3583 } 3584 3585 // Okay, we successfully defined 'Record'. 3586 if (Record) { 3587 Record->completeDefinition(Context); 3588 } else { 3589 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3590 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3591 ID->setIVarList(ClsFields, RecFields.size(), Context); 3592 ID->setLocEnd(RBrac); 3593 3594 // Must enforce the rule that ivars in the base classes may not be 3595 // duplicates. 3596 if (ID->getSuperClass()) { 3597 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3598 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3599 ObjCIvarDecl* Ivar = (*IVI); 3600 IdentifierInfo *II = Ivar->getIdentifier(); 3601 ObjCIvarDecl* prevIvar = 3602 ID->getSuperClass()->lookupInstanceVariable(II); 3603 if (prevIvar) { 3604 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3605 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3606 } 3607 } 3608 } 3609 } else if (ObjCImplementationDecl *IMPDecl = 3610 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3611 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3612 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3613 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3614 } 3615 } 3616 3617 if (Attr) 3618 ProcessDeclAttributeList(Record, Attr); 3619} 3620 3621Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3622 DeclTy *lastEnumConst, 3623 SourceLocation IdLoc, IdentifierInfo *Id, 3624 SourceLocation EqualLoc, ExprTy *val) { 3625 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3626 EnumConstantDecl *LastEnumConst = 3627 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3628 Expr *Val = static_cast<Expr*>(val); 3629 3630 // The scope passed in may not be a decl scope. Zip up the scope tree until 3631 // we find one that is. 3632 S = getNonFieldDeclScope(S); 3633 3634 // Verify that there isn't already something declared with this name in this 3635 // scope. 3636 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3637 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3638 // Maybe we will complain about the shadowed template parameter. 3639 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3640 // Just pretend that we didn't see the previous declaration. 3641 PrevDecl = 0; 3642 } 3643 3644 if (PrevDecl) { 3645 // When in C++, we may get a TagDecl with the same name; in this case the 3646 // enum constant will 'hide' the tag. 3647 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3648 "Received TagDecl when not in C++!"); 3649 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3650 if (isa<EnumConstantDecl>(PrevDecl)) 3651 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3652 else 3653 Diag(IdLoc, diag::err_redefinition) << Id; 3654 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3655 if (Val) Val->Destroy(Context); 3656 return 0; 3657 } 3658 } 3659 3660 llvm::APSInt EnumVal(32); 3661 QualType EltTy; 3662 if (Val) { 3663 // Make sure to promote the operand type to int. 3664 UsualUnaryConversions(Val); 3665 3666 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3667 SourceLocation ExpLoc; 3668 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3669 Val->Destroy(Context); 3670 Val = 0; // Just forget about it. 3671 } else { 3672 EltTy = Val->getType(); 3673 } 3674 } 3675 3676 if (!Val) { 3677 if (LastEnumConst) { 3678 // Assign the last value + 1. 3679 EnumVal = LastEnumConst->getInitVal(); 3680 ++EnumVal; 3681 3682 // Check for overflow on increment. 3683 if (EnumVal < LastEnumConst->getInitVal()) 3684 Diag(IdLoc, diag::warn_enum_value_overflow); 3685 3686 EltTy = LastEnumConst->getType(); 3687 } else { 3688 // First value, set to zero. 3689 EltTy = Context.IntTy; 3690 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3691 } 3692 } 3693 3694 EnumConstantDecl *New = 3695 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3696 Val, EnumVal); 3697 3698 // Register this decl in the current scope stack. 3699 PushOnScopeChains(New, S); 3700 3701 return New; 3702} 3703 3704// FIXME: For consistency with ActOnFields(), we should have the parser 3705// pass in the source location for the left/right braces. 3706void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3707 DeclTy **Elements, unsigned NumElements) { 3708 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3709 QualType EnumType = Context.getTypeDeclType(Enum); 3710 3711 // TODO: If the result value doesn't fit in an int, it must be a long or long 3712 // long value. ISO C does not support this, but GCC does as an extension, 3713 // emit a warning. 3714 unsigned IntWidth = Context.Target.getIntWidth(); 3715 3716 // Verify that all the values are okay, compute the size of the values, and 3717 // reverse the list. 3718 unsigned NumNegativeBits = 0; 3719 unsigned NumPositiveBits = 0; 3720 3721 // Keep track of whether all elements have type int. 3722 bool AllElementsInt = true; 3723 3724 for (unsigned i = 0; i != NumElements; ++i) { 3725 EnumConstantDecl *ECD = 3726 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3727 if (!ECD) continue; // Already issued a diagnostic. 3728 3729 // If the enum value doesn't fit in an int, emit an extension warning. 3730 const llvm::APSInt &InitVal = ECD->getInitVal(); 3731 assert(InitVal.getBitWidth() >= IntWidth && 3732 "Should have promoted value to int"); 3733 if (InitVal.getBitWidth() > IntWidth) { 3734 llvm::APSInt V(InitVal); 3735 V.trunc(IntWidth); 3736 V.extend(InitVal.getBitWidth()); 3737 if (V != InitVal) 3738 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3739 << InitVal.toString(10); 3740 } 3741 3742 // Keep track of the size of positive and negative values. 3743 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3744 NumPositiveBits = std::max(NumPositiveBits, 3745 (unsigned)InitVal.getActiveBits()); 3746 else 3747 NumNegativeBits = std::max(NumNegativeBits, 3748 (unsigned)InitVal.getMinSignedBits()); 3749 3750 // Keep track of whether every enum element has type int (very commmon). 3751 if (AllElementsInt) 3752 AllElementsInt = ECD->getType() == Context.IntTy; 3753 } 3754 3755 // Figure out the type that should be used for this enum. 3756 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3757 QualType BestType; 3758 unsigned BestWidth; 3759 3760 if (NumNegativeBits) { 3761 // If there is a negative value, figure out the smallest integer type (of 3762 // int/long/longlong) that fits. 3763 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3764 BestType = Context.IntTy; 3765 BestWidth = IntWidth; 3766 } else { 3767 BestWidth = Context.Target.getLongWidth(); 3768 3769 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3770 BestType = Context.LongTy; 3771 else { 3772 BestWidth = Context.Target.getLongLongWidth(); 3773 3774 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3775 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3776 BestType = Context.LongLongTy; 3777 } 3778 } 3779 } else { 3780 // If there is no negative value, figure out which of uint, ulong, ulonglong 3781 // fits. 3782 if (NumPositiveBits <= IntWidth) { 3783 BestType = Context.UnsignedIntTy; 3784 BestWidth = IntWidth; 3785 } else if (NumPositiveBits <= 3786 (BestWidth = Context.Target.getLongWidth())) { 3787 BestType = Context.UnsignedLongTy; 3788 } else { 3789 BestWidth = Context.Target.getLongLongWidth(); 3790 assert(NumPositiveBits <= BestWidth && 3791 "How could an initializer get larger than ULL?"); 3792 BestType = Context.UnsignedLongLongTy; 3793 } 3794 } 3795 3796 // Loop over all of the enumerator constants, changing their types to match 3797 // the type of the enum if needed. 3798 for (unsigned i = 0; i != NumElements; ++i) { 3799 EnumConstantDecl *ECD = 3800 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3801 if (!ECD) continue; // Already issued a diagnostic. 3802 3803 // Standard C says the enumerators have int type, but we allow, as an 3804 // extension, the enumerators to be larger than int size. If each 3805 // enumerator value fits in an int, type it as an int, otherwise type it the 3806 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3807 // that X has type 'int', not 'unsigned'. 3808 if (ECD->getType() == Context.IntTy) { 3809 // Make sure the init value is signed. 3810 llvm::APSInt IV = ECD->getInitVal(); 3811 IV.setIsSigned(true); 3812 ECD->setInitVal(IV); 3813 3814 if (getLangOptions().CPlusPlus) 3815 // C++ [dcl.enum]p4: Following the closing brace of an 3816 // enum-specifier, each enumerator has the type of its 3817 // enumeration. 3818 ECD->setType(EnumType); 3819 continue; // Already int type. 3820 } 3821 3822 // Determine whether the value fits into an int. 3823 llvm::APSInt InitVal = ECD->getInitVal(); 3824 bool FitsInInt; 3825 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3826 FitsInInt = InitVal.getActiveBits() < IntWidth; 3827 else 3828 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3829 3830 // If it fits into an integer type, force it. Otherwise force it to match 3831 // the enum decl type. 3832 QualType NewTy; 3833 unsigned NewWidth; 3834 bool NewSign; 3835 if (FitsInInt) { 3836 NewTy = Context.IntTy; 3837 NewWidth = IntWidth; 3838 NewSign = true; 3839 } else if (ECD->getType() == BestType) { 3840 // Already the right type! 3841 if (getLangOptions().CPlusPlus) 3842 // C++ [dcl.enum]p4: Following the closing brace of an 3843 // enum-specifier, each enumerator has the type of its 3844 // enumeration. 3845 ECD->setType(EnumType); 3846 continue; 3847 } else { 3848 NewTy = BestType; 3849 NewWidth = BestWidth; 3850 NewSign = BestType->isSignedIntegerType(); 3851 } 3852 3853 // Adjust the APSInt value. 3854 InitVal.extOrTrunc(NewWidth); 3855 InitVal.setIsSigned(NewSign); 3856 ECD->setInitVal(InitVal); 3857 3858 // Adjust the Expr initializer and type. 3859 if (ECD->getInitExpr()) 3860 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3861 /*isLvalue=*/false)); 3862 if (getLangOptions().CPlusPlus) 3863 // C++ [dcl.enum]p4: Following the closing brace of an 3864 // enum-specifier, each enumerator has the type of its 3865 // enumeration. 3866 ECD->setType(EnumType); 3867 else 3868 ECD->setType(NewTy); 3869 } 3870 3871 Enum->completeDefinition(Context, BestType); 3872} 3873 3874Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3875 ExprArg expr) { 3876 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3877 3878 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3879} 3880 3881