SemaDecl.cpp revision 85a5319ea4b5c916d7dd665e84af61e4a8a0b9c2
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/Parse/DeclSpec.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31using namespace clang; 32 33/// getDeclName - Return a pretty name for the specified decl if possible, or 34/// an empty string if not. This is used for pretty crash reporting. 35std::string Sema::getDeclName(DeclPtrTy d) { 36 Decl *D = d.getAs<Decl>(); 37 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 38 return DN->getQualifiedNameAsString(); 39 return ""; 40} 41 42Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 43 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 44} 45 46/// \brief If the identifier refers to a type name within this scope, 47/// return the declaration of that type. 48/// 49/// This routine performs ordinary name lookup of the identifier II 50/// within the given scope, with optional C++ scope specifier SS, to 51/// determine whether the name refers to a type. If so, returns an 52/// opaque pointer (actually a QualType) corresponding to that 53/// type. Otherwise, returns NULL. 54/// 55/// If name lookup results in an ambiguity, this routine will complain 56/// and then return NULL. 57Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 58 Scope *S, const CXXScopeSpec *SS) { 59 // C++ [temp.res]p3: 60 // A qualified-id that refers to a type and in which the 61 // nested-name-specifier depends on a template-parameter (14.6.2) 62 // shall be prefixed by the keyword typename to indicate that the 63 // qualified-id denotes a type, forming an 64 // elaborated-type-specifier (7.1.5.3). 65 // 66 // We therefore do not perform any name lookup up SS is a dependent 67 // scope name. FIXME: we will need to perform a special kind of 68 // lookup if the scope specifier names a member of the current 69 // instantiation. 70 if (SS && isDependentScopeSpecifier(*SS)) 71 return 0; 72 73 NamedDecl *IIDecl = 0; 74 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 75 false, false); 76 switch (Result.getKind()) { 77 case LookupResult::NotFound: 78 case LookupResult::FoundOverloaded: 79 return 0; 80 81 case LookupResult::AmbiguousBaseSubobjectTypes: 82 case LookupResult::AmbiguousBaseSubobjects: 83 case LookupResult::AmbiguousReference: { 84 // Look to see if we have a type anywhere in the list of results. 85 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 86 Res != ResEnd; ++Res) { 87 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 88 IIDecl = *Res; 89 break; 90 } 91 } 92 93 if (!IIDecl) { 94 // None of the entities we found is a type, so there is no way 95 // to even assume that the result is a type. In this case, don't 96 // complain about the ambiguity. The parser will either try to 97 // perform this lookup again (e.g., as an object name), which 98 // will produce the ambiguity, or will complain that it expected 99 // a type name. 100 Result.Destroy(); 101 return 0; 102 } 103 104 // We found a type within the ambiguous lookup; diagnose the 105 // ambiguity and then return that type. This might be the right 106 // answer, or it might not be, but it suppresses any attempt to 107 // perform the name lookup again. 108 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 109 break; 110 } 111 112 case LookupResult::Found: 113 IIDecl = Result.getAsDecl(); 114 break; 115 } 116 117 if (IIDecl) { 118 QualType T; 119 120 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 121 // Check whether we can use this type 122 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 123 124 T = Context.getTypeDeclType(TD); 125 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 126 // Check whether we can use this interface. 127 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 128 129 T = Context.getObjCInterfaceType(IDecl); 130 } else 131 return 0; 132 133 if (SS) 134 T = getQualifiedNameType(*SS, T); 135 136 return T.getAsOpaquePtr(); 137 } 138 139 return 0; 140} 141 142DeclContext *Sema::getContainingDC(DeclContext *DC) { 143 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 144 // A C++ out-of-line method will return to the file declaration context. 145 if (MD->isOutOfLineDefinition()) 146 return MD->getLexicalDeclContext(); 147 148 // A C++ inline method is parsed *after* the topmost class it was declared 149 // in is fully parsed (it's "complete"). 150 // The parsing of a C++ inline method happens at the declaration context of 151 // the topmost (non-nested) class it is lexically declared in. 152 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 153 DC = MD->getParent(); 154 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 155 DC = RD; 156 157 // Return the declaration context of the topmost class the inline method is 158 // declared in. 159 return DC; 160 } 161 162 if (isa<ObjCMethodDecl>(DC)) 163 return Context.getTranslationUnitDecl(); 164 165 return DC->getLexicalParent(); 166} 167 168void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 169 assert(getContainingDC(DC) == CurContext && 170 "The next DeclContext should be lexically contained in the current one."); 171 CurContext = DC; 172 S->setEntity(DC); 173} 174 175void Sema::PopDeclContext() { 176 assert(CurContext && "DeclContext imbalance!"); 177 178 CurContext = getContainingDC(CurContext); 179} 180 181/// \brief Determine whether we allow overloading of the function 182/// PrevDecl with another declaration. 183/// 184/// This routine determines whether overloading is possible, not 185/// whether some new function is actually an overload. It will return 186/// true in C++ (where we can always provide overloads) or, as an 187/// extension, in C when the previous function is already an 188/// overloaded function declaration or has the "overloadable" 189/// attribute. 190static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 191 if (Context.getLangOptions().CPlusPlus) 192 return true; 193 194 if (isa<OverloadedFunctionDecl>(PrevDecl)) 195 return true; 196 197 return PrevDecl->getAttr<OverloadableAttr>() != 0; 198} 199 200/// Add this decl to the scope shadowed decl chains. 201void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 202 // Move up the scope chain until we find the nearest enclosing 203 // non-transparent context. The declaration will be introduced into this 204 // scope. 205 while (S->getEntity() && 206 ((DeclContext *)S->getEntity())->isTransparentContext()) 207 S = S->getParent(); 208 209 S->AddDecl(DeclPtrTy::make(D)); 210 211 // Add scoped declarations into their context, so that they can be 212 // found later. Declarations without a context won't be inserted 213 // into any context. 214 CurContext->addDecl(D); 215 216 // C++ [basic.scope]p4: 217 // -- exactly one declaration shall declare a class name or 218 // enumeration name that is not a typedef name and the other 219 // declarations shall all refer to the same object or 220 // enumerator, or all refer to functions and function templates; 221 // in this case the class name or enumeration name is hidden. 222 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 223 // We are pushing the name of a tag (enum or class). 224 if (CurContext->getLookupContext() 225 == TD->getDeclContext()->getLookupContext()) { 226 // We're pushing the tag into the current context, which might 227 // require some reshuffling in the identifier resolver. 228 IdentifierResolver::iterator 229 I = IdResolver.begin(TD->getDeclName()), 230 IEnd = IdResolver.end(); 231 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 232 NamedDecl *PrevDecl = *I; 233 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 234 PrevDecl = *I, ++I) { 235 if (TD->declarationReplaces(*I)) { 236 // This is a redeclaration. Remove it from the chain and 237 // break out, so that we'll add in the shadowed 238 // declaration. 239 S->RemoveDecl(DeclPtrTy::make(*I)); 240 if (PrevDecl == *I) { 241 IdResolver.RemoveDecl(*I); 242 IdResolver.AddDecl(TD); 243 return; 244 } else { 245 IdResolver.RemoveDecl(*I); 246 break; 247 } 248 } 249 } 250 251 // There is already a declaration with the same name in the same 252 // scope, which is not a tag declaration. It must be found 253 // before we find the new declaration, so insert the new 254 // declaration at the end of the chain. 255 IdResolver.AddShadowedDecl(TD, PrevDecl); 256 257 return; 258 } 259 } 260 } else if (isa<FunctionDecl>(D) && 261 AllowOverloadingOfFunction(D, Context)) { 262 // We are pushing the name of a function, which might be an 263 // overloaded name. 264 FunctionDecl *FD = cast<FunctionDecl>(D); 265 IdentifierResolver::iterator Redecl 266 = std::find_if(IdResolver.begin(FD->getDeclName()), 267 IdResolver.end(), 268 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 269 FD)); 270 if (Redecl != IdResolver.end() && 271 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 272 // There is already a declaration of a function on our 273 // IdResolver chain. Replace it with this declaration. 274 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 275 IdResolver.RemoveDecl(*Redecl); 276 } 277 } 278 279 IdResolver.AddDecl(D); 280} 281 282void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 283 if (S->decl_empty()) return; 284 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 285 "Scope shouldn't contain decls!"); 286 287 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 288 I != E; ++I) { 289 Decl *TmpD = (*I).getAs<Decl>(); 290 assert(TmpD && "This decl didn't get pushed??"); 291 292 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 293 NamedDecl *D = cast<NamedDecl>(TmpD); 294 295 if (!D->getDeclName()) continue; 296 297 // Remove this name from our lexical scope. 298 IdResolver.RemoveDecl(D); 299 } 300} 301 302/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 303/// return 0 if one not found. 304ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 305 // The third "scope" argument is 0 since we aren't enabling lazy built-in 306 // creation from this context. 307 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 308 309 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 310} 311 312/// getNonFieldDeclScope - Retrieves the innermost scope, starting 313/// from S, where a non-field would be declared. This routine copes 314/// with the difference between C and C++ scoping rules in structs and 315/// unions. For example, the following code is well-formed in C but 316/// ill-formed in C++: 317/// @code 318/// struct S6 { 319/// enum { BAR } e; 320/// }; 321/// 322/// void test_S6() { 323/// struct S6 a; 324/// a.e = BAR; 325/// } 326/// @endcode 327/// For the declaration of BAR, this routine will return a different 328/// scope. The scope S will be the scope of the unnamed enumeration 329/// within S6. In C++, this routine will return the scope associated 330/// with S6, because the enumeration's scope is a transparent 331/// context but structures can contain non-field names. In C, this 332/// routine will return the translation unit scope, since the 333/// enumeration's scope is a transparent context and structures cannot 334/// contain non-field names. 335Scope *Sema::getNonFieldDeclScope(Scope *S) { 336 while (((S->getFlags() & Scope::DeclScope) == 0) || 337 (S->getEntity() && 338 ((DeclContext *)S->getEntity())->isTransparentContext()) || 339 (S->isClassScope() && !getLangOptions().CPlusPlus)) 340 S = S->getParent(); 341 return S; 342} 343 344void Sema::InitBuiltinVaListType() { 345 if (!Context.getBuiltinVaListType().isNull()) 346 return; 347 348 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 349 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 350 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 351 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 352} 353 354/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 355/// file scope. lazily create a decl for it. ForRedeclaration is true 356/// if we're creating this built-in in anticipation of redeclaring the 357/// built-in. 358NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 359 Scope *S, bool ForRedeclaration, 360 SourceLocation Loc) { 361 Builtin::ID BID = (Builtin::ID)bid; 362 363 if (Context.BuiltinInfo.hasVAListUse(BID)) 364 InitBuiltinVaListType(); 365 366 Builtin::Context::GetBuiltinTypeError Error; 367 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 368 switch (Error) { 369 case Builtin::Context::GE_None: 370 // Okay 371 break; 372 373 case Builtin::Context::GE_Missing_FILE: 374 if (ForRedeclaration) 375 Diag(Loc, diag::err_implicit_decl_requires_stdio) 376 << Context.BuiltinInfo.GetName(BID); 377 return 0; 378 } 379 380 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 381 Diag(Loc, diag::ext_implicit_lib_function_decl) 382 << Context.BuiltinInfo.GetName(BID) 383 << R; 384 if (Context.BuiltinInfo.getHeaderName(BID) && 385 Diags.getDiagnosticMapping(diag::ext_implicit_lib_function_decl) 386 != diag::MAP_IGNORE) 387 Diag(Loc, diag::note_please_include_header) 388 << Context.BuiltinInfo.getHeaderName(BID) 389 << Context.BuiltinInfo.GetName(BID); 390 } 391 392 FunctionDecl *New = FunctionDecl::Create(Context, 393 Context.getTranslationUnitDecl(), 394 Loc, II, R, 395 FunctionDecl::Extern, false, 396 /*hasPrototype=*/true); 397 New->setImplicit(); 398 399 // Create Decl objects for each parameter, adding them to the 400 // FunctionDecl. 401 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 402 llvm::SmallVector<ParmVarDecl*, 16> Params; 403 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 404 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 405 FT->getArgType(i), VarDecl::None, 0)); 406 New->setParams(Context, &Params[0], Params.size()); 407 } 408 409 AddKnownFunctionAttributes(New); 410 411 // TUScope is the translation-unit scope to insert this function into. 412 // FIXME: This is hideous. We need to teach PushOnScopeChains to 413 // relate Scopes to DeclContexts, and probably eliminate CurContext 414 // entirely, but we're not there yet. 415 DeclContext *SavedContext = CurContext; 416 CurContext = Context.getTranslationUnitDecl(); 417 PushOnScopeChains(New, TUScope); 418 CurContext = SavedContext; 419 return New; 420} 421 422/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 423/// everything from the standard library is defined. 424NamespaceDecl *Sema::GetStdNamespace() { 425 if (!StdNamespace) { 426 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 427 DeclContext *Global = Context.getTranslationUnitDecl(); 428 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 429 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 430 } 431 return StdNamespace; 432} 433 434/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 435/// same name and scope as a previous declaration 'Old'. Figure out 436/// how to resolve this situation, merging decls or emitting 437/// diagnostics as appropriate. Returns true if there was an error, 438/// false otherwise. 439/// 440bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 441 bool objc_types = false; 442 // Allow multiple definitions for ObjC built-in typedefs. 443 // FIXME: Verify the underlying types are equivalent! 444 if (getLangOptions().ObjC1) { 445 const IdentifierInfo *TypeID = New->getIdentifier(); 446 switch (TypeID->getLength()) { 447 default: break; 448 case 2: 449 if (!TypeID->isStr("id")) 450 break; 451 Context.setObjCIdType(New); 452 objc_types = true; 453 break; 454 case 5: 455 if (!TypeID->isStr("Class")) 456 break; 457 Context.setObjCClassType(New); 458 objc_types = true; 459 return false; 460 case 3: 461 if (!TypeID->isStr("SEL")) 462 break; 463 Context.setObjCSelType(New); 464 objc_types = true; 465 return false; 466 case 8: 467 if (!TypeID->isStr("Protocol")) 468 break; 469 Context.setObjCProtoType(New->getUnderlyingType()); 470 objc_types = true; 471 return false; 472 } 473 // Fall through - the typedef name was not a builtin type. 474 } 475 // Verify the old decl was also a type. 476 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 477 if (!Old) { 478 Diag(New->getLocation(), diag::err_redefinition_different_kind) 479 << New->getDeclName(); 480 if (!objc_types) 481 Diag(OldD->getLocation(), diag::note_previous_definition); 482 return true; 483 } 484 485 // Determine the "old" type we'll use for checking and diagnostics. 486 QualType OldType; 487 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 488 OldType = OldTypedef->getUnderlyingType(); 489 else 490 OldType = Context.getTypeDeclType(Old); 491 492 // If the typedef types are not identical, reject them in all languages and 493 // with any extensions enabled. 494 495 if (OldType != New->getUnderlyingType() && 496 Context.getCanonicalType(OldType) != 497 Context.getCanonicalType(New->getUnderlyingType())) { 498 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 499 << New->getUnderlyingType() << OldType; 500 if (!objc_types) 501 Diag(Old->getLocation(), diag::note_previous_definition); 502 return true; 503 } 504 if (objc_types) return false; 505 if (getLangOptions().Microsoft) return false; 506 507 // C++ [dcl.typedef]p2: 508 // In a given non-class scope, a typedef specifier can be used to 509 // redefine the name of any type declared in that scope to refer 510 // to the type to which it already refers. 511 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 512 return false; 513 514 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 515 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 516 // *either* declaration is in a system header. The code below implements 517 // this adhoc compatibility rule. FIXME: The following code will not 518 // work properly when compiling ".i" files (containing preprocessed output). 519 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 520 SourceManager &SrcMgr = Context.getSourceManager(); 521 if (SrcMgr.isInSystemHeader(Old->getLocation())) 522 return false; 523 if (SrcMgr.isInSystemHeader(New->getLocation())) 524 return false; 525 } 526 527 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 528 Diag(Old->getLocation(), diag::note_previous_definition); 529 return true; 530} 531 532/// DeclhasAttr - returns true if decl Declaration already has the target 533/// attribute. 534static bool DeclHasAttr(const Decl *decl, const Attr *target) { 535 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 536 if (attr->getKind() == target->getKind()) 537 return true; 538 539 return false; 540} 541 542/// MergeAttributes - append attributes from the Old decl to the New one. 543static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 544 Attr *attr = const_cast<Attr*>(Old->getAttrs()); 545 546 while (attr) { 547 Attr *tmp = attr; 548 attr = attr->getNext(); 549 550 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 551 tmp->setInherited(true); 552 New->addAttr(tmp); 553 } else { 554 tmp->setNext(0); 555 tmp->Destroy(C); 556 } 557 } 558 559 Old->invalidateAttrs(); 560} 561 562/// Used in MergeFunctionDecl to keep track of function parameters in 563/// C. 564struct GNUCompatibleParamWarning { 565 ParmVarDecl *OldParm; 566 ParmVarDecl *NewParm; 567 QualType PromotedType; 568}; 569 570/// MergeFunctionDecl - We just parsed a function 'New' from 571/// declarator D which has the same name and scope as a previous 572/// declaration 'Old'. Figure out how to resolve this situation, 573/// merging decls or emitting diagnostics as appropriate. 574/// 575/// In C++, New and Old must be declarations that are not 576/// overloaded. Use IsOverload to determine whether New and Old are 577/// overloaded, and to select the Old declaration that New should be 578/// merged with. 579/// 580/// Returns true if there was an error, false otherwise. 581bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 582 assert(!isa<OverloadedFunctionDecl>(OldD) && 583 "Cannot merge with an overloaded function declaration"); 584 585 // Verify the old decl was also a function. 586 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 587 if (!Old) { 588 Diag(New->getLocation(), diag::err_redefinition_different_kind) 589 << New->getDeclName(); 590 Diag(OldD->getLocation(), diag::note_previous_definition); 591 return true; 592 } 593 594 // Determine whether the previous declaration was a definition, 595 // implicit declaration, or a declaration. 596 diag::kind PrevDiag; 597 if (Old->isThisDeclarationADefinition()) 598 PrevDiag = diag::note_previous_definition; 599 else if (Old->isImplicit()) 600 PrevDiag = diag::note_previous_implicit_declaration; 601 else 602 PrevDiag = diag::note_previous_declaration; 603 604 QualType OldQType = Context.getCanonicalType(Old->getType()); 605 QualType NewQType = Context.getCanonicalType(New->getType()); 606 607 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 608 New->getStorageClass() == FunctionDecl::Static && 609 Old->getStorageClass() != FunctionDecl::Static) { 610 Diag(New->getLocation(), diag::err_static_non_static) 611 << New; 612 Diag(Old->getLocation(), PrevDiag); 613 return true; 614 } 615 616 if (getLangOptions().CPlusPlus) { 617 // (C++98 13.1p2): 618 // Certain function declarations cannot be overloaded: 619 // -- Function declarations that differ only in the return type 620 // cannot be overloaded. 621 QualType OldReturnType 622 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 623 QualType NewReturnType 624 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 625 if (OldReturnType != NewReturnType) { 626 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 627 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 628 return true; 629 } 630 631 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 632 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 633 if (OldMethod && NewMethod && 634 OldMethod->getLexicalDeclContext() == 635 NewMethod->getLexicalDeclContext()) { 636 // -- Member function declarations with the same name and the 637 // same parameter types cannot be overloaded if any of them 638 // is a static member function declaration. 639 if (OldMethod->isStatic() || NewMethod->isStatic()) { 640 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 641 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 642 return true; 643 } 644 645 // C++ [class.mem]p1: 646 // [...] A member shall not be declared twice in the 647 // member-specification, except that a nested class or member 648 // class template can be declared and then later defined. 649 unsigned NewDiag; 650 if (isa<CXXConstructorDecl>(OldMethod)) 651 NewDiag = diag::err_constructor_redeclared; 652 else if (isa<CXXDestructorDecl>(NewMethod)) 653 NewDiag = diag::err_destructor_redeclared; 654 else if (isa<CXXConversionDecl>(NewMethod)) 655 NewDiag = diag::err_conv_function_redeclared; 656 else 657 NewDiag = diag::err_member_redeclared; 658 659 Diag(New->getLocation(), NewDiag); 660 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 661 } 662 663 // (C++98 8.3.5p3): 664 // All declarations for a function shall agree exactly in both the 665 // return type and the parameter-type-list. 666 if (OldQType == NewQType) 667 return MergeCompatibleFunctionDecls(New, Old); 668 669 // Fall through for conflicting redeclarations and redefinitions. 670 } 671 672 // C: Function types need to be compatible, not identical. This handles 673 // duplicate function decls like "void f(int); void f(enum X);" properly. 674 if (!getLangOptions().CPlusPlus && 675 Context.typesAreCompatible(OldQType, NewQType)) { 676 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 677 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 678 const FunctionProtoType *OldProto = 0; 679 if (isa<FunctionNoProtoType>(NewFuncType) && 680 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 681 // The old declaration provided a function prototype, but the 682 // new declaration does not. Merge in the prototype. 683 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 684 OldProto->arg_type_end()); 685 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 686 &ParamTypes[0], ParamTypes.size(), 687 OldProto->isVariadic(), 688 OldProto->getTypeQuals()); 689 New->setType(NewQType); 690 New->setInheritedPrototype(); 691 692 // Synthesize a parameter for each argument type. 693 llvm::SmallVector<ParmVarDecl*, 16> Params; 694 for (FunctionProtoType::arg_type_iterator 695 ParamType = OldProto->arg_type_begin(), 696 ParamEnd = OldProto->arg_type_end(); 697 ParamType != ParamEnd; ++ParamType) { 698 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 699 SourceLocation(), 0, 700 *ParamType, VarDecl::None, 701 0); 702 Param->setImplicit(); 703 Params.push_back(Param); 704 } 705 706 New->setParams(Context, &Params[0], Params.size()); 707 } 708 709 return MergeCompatibleFunctionDecls(New, Old); 710 } 711 712 // GNU C permits a K&R definition to follow a prototype declaration 713 // if the declared types of the parameters in the K&R definition 714 // match the types in the prototype declaration, even when the 715 // promoted types of the parameters from the K&R definition differ 716 // from the types in the prototype. GCC then keeps the types from 717 // the prototype. 718 if (!getLangOptions().CPlusPlus && 719 !getLangOptions().NoExtensions && 720 Old->hasPrototype() && !New->hasPrototype() && 721 New->getType()->getAsFunctionProtoType() && 722 Old->getNumParams() == New->getNumParams()) { 723 llvm::SmallVector<QualType, 16> ArgTypes; 724 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 725 const FunctionProtoType *OldProto 726 = Old->getType()->getAsFunctionProtoType(); 727 const FunctionProtoType *NewProto 728 = New->getType()->getAsFunctionProtoType(); 729 730 // Determine whether this is the GNU C extension. 731 bool GNUCompatible = 732 Context.typesAreCompatible(OldProto->getResultType(), 733 NewProto->getResultType()) && 734 (OldProto->isVariadic() == NewProto->isVariadic()); 735 for (unsigned Idx = 0, End = Old->getNumParams(); 736 GNUCompatible && Idx != End; ++Idx) { 737 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 738 ParmVarDecl *NewParm = New->getParamDecl(Idx); 739 if (Context.typesAreCompatible(OldParm->getType(), 740 NewProto->getArgType(Idx))) { 741 ArgTypes.push_back(NewParm->getType()); 742 } else if (Context.typesAreCompatible(OldParm->getType(), 743 NewParm->getType())) { 744 GNUCompatibleParamWarning Warn 745 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 746 Warnings.push_back(Warn); 747 ArgTypes.push_back(NewParm->getType()); 748 } else 749 GNUCompatible = false; 750 } 751 752 if (GNUCompatible) { 753 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 754 Diag(Warnings[Warn].NewParm->getLocation(), 755 diag::ext_param_promoted_not_compatible_with_prototype) 756 << Warnings[Warn].PromotedType 757 << Warnings[Warn].OldParm->getType(); 758 Diag(Warnings[Warn].OldParm->getLocation(), 759 diag::note_previous_declaration); 760 } 761 762 New->setType(Context.getFunctionType(NewProto->getResultType(), 763 &ArgTypes[0], ArgTypes.size(), 764 NewProto->isVariadic(), 765 NewProto->getTypeQuals())); 766 return MergeCompatibleFunctionDecls(New, Old); 767 } 768 769 // Fall through to diagnose conflicting types. 770 } 771 772 // A function that has already been declared has been redeclared or defined 773 // with a different type- show appropriate diagnostic 774 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 775 // The user has declared a builtin function with an incompatible 776 // signature. 777 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 778 // The function the user is redeclaring is a library-defined 779 // function like 'malloc' or 'printf'. Warn about the 780 // redeclaration, then pretend that we don't know about this 781 // library built-in. 782 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 783 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 784 << Old << Old->getType(); 785 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 786 Old->setInvalidDecl(); 787 return false; 788 } 789 790 PrevDiag = diag::note_previous_builtin_declaration; 791 } 792 793 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 794 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 795 return true; 796} 797 798/// \brief Completes the merge of two function declarations that are 799/// known to be compatible. 800/// 801/// This routine handles the merging of attributes and other 802/// properties of function declarations form the old declaration to 803/// the new declaration, once we know that New is in fact a 804/// redeclaration of Old. 805/// 806/// \returns false 807bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 808 // Merge the attributes 809 MergeAttributes(New, Old, Context); 810 811 // Merge the storage class. 812 New->setStorageClass(Old->getStorageClass()); 813 814 // FIXME: need to implement inline semantics 815 816 // Merge "pure" flag. 817 if (Old->isPure()) 818 New->setPure(); 819 820 // Merge the "deleted" flag. 821 if (Old->isDeleted()) 822 New->setDeleted(); 823 824 if (getLangOptions().CPlusPlus) 825 return MergeCXXFunctionDecl(New, Old); 826 827 return false; 828} 829 830/// MergeVarDecl - We just parsed a variable 'New' which has the same name 831/// and scope as a previous declaration 'Old'. Figure out how to resolve this 832/// situation, merging decls or emitting diagnostics as appropriate. 833/// 834/// Tentative definition rules (C99 6.9.2p2) are checked by 835/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 836/// definitions here, since the initializer hasn't been attached. 837/// 838bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 839 // Verify the old decl was also a variable. 840 VarDecl *Old = dyn_cast<VarDecl>(OldD); 841 if (!Old) { 842 Diag(New->getLocation(), diag::err_redefinition_different_kind) 843 << New->getDeclName(); 844 Diag(OldD->getLocation(), diag::note_previous_definition); 845 return true; 846 } 847 848 MergeAttributes(New, Old, Context); 849 850 // Merge the types 851 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 852 if (MergedT.isNull()) { 853 Diag(New->getLocation(), diag::err_redefinition_different_type) 854 << New->getDeclName(); 855 Diag(Old->getLocation(), diag::note_previous_definition); 856 return true; 857 } 858 New->setType(MergedT); 859 860 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 861 if (New->getStorageClass() == VarDecl::Static && 862 (Old->getStorageClass() == VarDecl::None || 863 Old->getStorageClass() == VarDecl::Extern)) { 864 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 865 Diag(Old->getLocation(), diag::note_previous_definition); 866 return true; 867 } 868 // C99 6.2.2p4: 869 // For an identifier declared with the storage-class specifier 870 // extern in a scope in which a prior declaration of that 871 // identifier is visible,23) if the prior declaration specifies 872 // internal or external linkage, the linkage of the identifier at 873 // the later declaration is the same as the linkage specified at 874 // the prior declaration. If no prior declaration is visible, or 875 // if the prior declaration specifies no linkage, then the 876 // identifier has external linkage. 877 if (New->hasExternalStorage() && Old->hasLinkage()) 878 /* Okay */; 879 else if (New->getStorageClass() != VarDecl::Static && 880 Old->getStorageClass() == VarDecl::Static) { 881 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 882 Diag(Old->getLocation(), diag::note_previous_definition); 883 return true; 884 } 885 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 886 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl() && 887 // Don't complain about out-of-line definitions of static members. 888 !(Old->getLexicalDeclContext()->isRecord() && 889 !New->getLexicalDeclContext()->isRecord())) { 890 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 891 Diag(Old->getLocation(), diag::note_previous_definition); 892 return true; 893 } 894 895 // Keep a chain of previous declarations. 896 New->setPreviousDeclaration(Old); 897 898 return false; 899} 900 901/// CheckParmsForFunctionDef - Check that the parameters of the given 902/// function are appropriate for the definition of a function. This 903/// takes care of any checks that cannot be performed on the 904/// declaration itself, e.g., that the types of each of the function 905/// parameters are complete. 906bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 907 bool HasInvalidParm = false; 908 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 909 ParmVarDecl *Param = FD->getParamDecl(p); 910 911 // C99 6.7.5.3p4: the parameters in a parameter type list in a 912 // function declarator that is part of a function definition of 913 // that function shall not have incomplete type. 914 // 915 // This is also C++ [dcl.fct]p6. 916 if (!Param->isInvalidDecl() && 917 RequireCompleteType(Param->getLocation(), Param->getType(), 918 diag::err_typecheck_decl_incomplete_type)) { 919 Param->setInvalidDecl(); 920 HasInvalidParm = true; 921 } 922 923 // C99 6.9.1p5: If the declarator includes a parameter type list, the 924 // declaration of each parameter shall include an identifier. 925 if (Param->getIdentifier() == 0 && 926 !Param->isImplicit() && 927 !getLangOptions().CPlusPlus) 928 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 929 } 930 931 return HasInvalidParm; 932} 933 934/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 935/// no declarator (e.g. "struct foo;") is parsed. 936Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 937 TagDecl *Tag = 0; 938 if (DS.getTypeSpecType() == DeclSpec::TST_class || 939 DS.getTypeSpecType() == DeclSpec::TST_struct || 940 DS.getTypeSpecType() == DeclSpec::TST_union || 941 DS.getTypeSpecType() == DeclSpec::TST_enum) 942 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 943 944 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 945 if (!Record->getDeclName() && Record->isDefinition() && 946 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 947 if (getLangOptions().CPlusPlus || 948 Record->getDeclContext()->isRecord()) 949 return BuildAnonymousStructOrUnion(S, DS, Record); 950 951 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 952 << DS.getSourceRange(); 953 } 954 955 // Microsoft allows unnamed struct/union fields. Don't complain 956 // about them. 957 // FIXME: Should we support Microsoft's extensions in this area? 958 if (Record->getDeclName() && getLangOptions().Microsoft) 959 return DeclPtrTy::make(Tag); 960 } 961 962 if (!DS.isMissingDeclaratorOk() && 963 DS.getTypeSpecType() != DeclSpec::TST_error) { 964 // Warn about typedefs of enums without names, since this is an 965 // extension in both Microsoft an GNU. 966 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 967 Tag && isa<EnumDecl>(Tag)) { 968 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 969 << DS.getSourceRange(); 970 return DeclPtrTy::make(Tag); 971 } 972 973 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 974 << DS.getSourceRange(); 975 return DeclPtrTy(); 976 } 977 978 return DeclPtrTy::make(Tag); 979} 980 981/// InjectAnonymousStructOrUnionMembers - Inject the members of the 982/// anonymous struct or union AnonRecord into the owning context Owner 983/// and scope S. This routine will be invoked just after we realize 984/// that an unnamed union or struct is actually an anonymous union or 985/// struct, e.g., 986/// 987/// @code 988/// union { 989/// int i; 990/// float f; 991/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 992/// // f into the surrounding scope.x 993/// @endcode 994/// 995/// This routine is recursive, injecting the names of nested anonymous 996/// structs/unions into the owning context and scope as well. 997bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 998 RecordDecl *AnonRecord) { 999 bool Invalid = false; 1000 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1001 FEnd = AnonRecord->field_end(); 1002 F != FEnd; ++F) { 1003 if ((*F)->getDeclName()) { 1004 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1005 LookupOrdinaryName, true); 1006 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1007 // C++ [class.union]p2: 1008 // The names of the members of an anonymous union shall be 1009 // distinct from the names of any other entity in the 1010 // scope in which the anonymous union is declared. 1011 unsigned diagKind 1012 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1013 : diag::err_anonymous_struct_member_redecl; 1014 Diag((*F)->getLocation(), diagKind) 1015 << (*F)->getDeclName(); 1016 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1017 Invalid = true; 1018 } else { 1019 // C++ [class.union]p2: 1020 // For the purpose of name lookup, after the anonymous union 1021 // definition, the members of the anonymous union are 1022 // considered to have been defined in the scope in which the 1023 // anonymous union is declared. 1024 Owner->makeDeclVisibleInContext(*F); 1025 S->AddDecl(DeclPtrTy::make(*F)); 1026 IdResolver.AddDecl(*F); 1027 } 1028 } else if (const RecordType *InnerRecordType 1029 = (*F)->getType()->getAsRecordType()) { 1030 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1031 if (InnerRecord->isAnonymousStructOrUnion()) 1032 Invalid = Invalid || 1033 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1034 } 1035 } 1036 1037 return Invalid; 1038} 1039 1040/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1041/// anonymous structure or union. Anonymous unions are a C++ feature 1042/// (C++ [class.union]) and a GNU C extension; anonymous structures 1043/// are a GNU C and GNU C++ extension. 1044Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1045 RecordDecl *Record) { 1046 DeclContext *Owner = Record->getDeclContext(); 1047 1048 // Diagnose whether this anonymous struct/union is an extension. 1049 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1050 Diag(Record->getLocation(), diag::ext_anonymous_union); 1051 else if (!Record->isUnion()) 1052 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1053 1054 // C and C++ require different kinds of checks for anonymous 1055 // structs/unions. 1056 bool Invalid = false; 1057 if (getLangOptions().CPlusPlus) { 1058 const char* PrevSpec = 0; 1059 // C++ [class.union]p3: 1060 // Anonymous unions declared in a named namespace or in the 1061 // global namespace shall be declared static. 1062 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1063 (isa<TranslationUnitDecl>(Owner) || 1064 (isa<NamespaceDecl>(Owner) && 1065 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1066 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1067 Invalid = true; 1068 1069 // Recover by adding 'static'. 1070 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1071 } 1072 // C++ [class.union]p3: 1073 // A storage class is not allowed in a declaration of an 1074 // anonymous union in a class scope. 1075 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1076 isa<RecordDecl>(Owner)) { 1077 Diag(DS.getStorageClassSpecLoc(), 1078 diag::err_anonymous_union_with_storage_spec); 1079 Invalid = true; 1080 1081 // Recover by removing the storage specifier. 1082 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1083 PrevSpec); 1084 } 1085 1086 // C++ [class.union]p2: 1087 // The member-specification of an anonymous union shall only 1088 // define non-static data members. [Note: nested types and 1089 // functions cannot be declared within an anonymous union. ] 1090 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1091 MemEnd = Record->decls_end(); 1092 Mem != MemEnd; ++Mem) { 1093 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1094 // C++ [class.union]p3: 1095 // An anonymous union shall not have private or protected 1096 // members (clause 11). 1097 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1098 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1099 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1100 Invalid = true; 1101 } 1102 } else if ((*Mem)->isImplicit()) { 1103 // Any implicit members are fine. 1104 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1105 // This is a type that showed up in an 1106 // elaborated-type-specifier inside the anonymous struct or 1107 // union, but which actually declares a type outside of the 1108 // anonymous struct or union. It's okay. 1109 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1110 if (!MemRecord->isAnonymousStructOrUnion() && 1111 MemRecord->getDeclName()) { 1112 // This is a nested type declaration. 1113 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1114 << (int)Record->isUnion(); 1115 Invalid = true; 1116 } 1117 } else { 1118 // We have something that isn't a non-static data 1119 // member. Complain about it. 1120 unsigned DK = diag::err_anonymous_record_bad_member; 1121 if (isa<TypeDecl>(*Mem)) 1122 DK = diag::err_anonymous_record_with_type; 1123 else if (isa<FunctionDecl>(*Mem)) 1124 DK = diag::err_anonymous_record_with_function; 1125 else if (isa<VarDecl>(*Mem)) 1126 DK = diag::err_anonymous_record_with_static; 1127 Diag((*Mem)->getLocation(), DK) 1128 << (int)Record->isUnion(); 1129 Invalid = true; 1130 } 1131 } 1132 } 1133 1134 if (!Record->isUnion() && !Owner->isRecord()) { 1135 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1136 << (int)getLangOptions().CPlusPlus; 1137 Invalid = true; 1138 } 1139 1140 // Create a declaration for this anonymous struct/union. 1141 NamedDecl *Anon = 0; 1142 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1143 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1144 /*IdentifierInfo=*/0, 1145 Context.getTypeDeclType(Record), 1146 /*BitWidth=*/0, /*Mutable=*/false); 1147 Anon->setAccess(AS_public); 1148 if (getLangOptions().CPlusPlus) 1149 FieldCollector->Add(cast<FieldDecl>(Anon)); 1150 } else { 1151 VarDecl::StorageClass SC; 1152 switch (DS.getStorageClassSpec()) { 1153 default: assert(0 && "Unknown storage class!"); 1154 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1155 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1156 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1157 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1158 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1159 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1160 case DeclSpec::SCS_mutable: 1161 // mutable can only appear on non-static class members, so it's always 1162 // an error here 1163 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1164 Invalid = true; 1165 SC = VarDecl::None; 1166 break; 1167 } 1168 1169 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1170 /*IdentifierInfo=*/0, 1171 Context.getTypeDeclType(Record), 1172 SC, DS.getSourceRange().getBegin()); 1173 } 1174 Anon->setImplicit(); 1175 1176 // Add the anonymous struct/union object to the current 1177 // context. We'll be referencing this object when we refer to one of 1178 // its members. 1179 Owner->addDecl(Anon); 1180 1181 // Inject the members of the anonymous struct/union into the owning 1182 // context and into the identifier resolver chain for name lookup 1183 // purposes. 1184 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1185 Invalid = true; 1186 1187 // Mark this as an anonymous struct/union type. Note that we do not 1188 // do this until after we have already checked and injected the 1189 // members of this anonymous struct/union type, because otherwise 1190 // the members could be injected twice: once by DeclContext when it 1191 // builds its lookup table, and once by 1192 // InjectAnonymousStructOrUnionMembers. 1193 Record->setAnonymousStructOrUnion(true); 1194 1195 if (Invalid) 1196 Anon->setInvalidDecl(); 1197 1198 return DeclPtrTy::make(Anon); 1199} 1200 1201 1202/// GetNameForDeclarator - Determine the full declaration name for the 1203/// given Declarator. 1204DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1205 switch (D.getKind()) { 1206 case Declarator::DK_Abstract: 1207 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1208 return DeclarationName(); 1209 1210 case Declarator::DK_Normal: 1211 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1212 return DeclarationName(D.getIdentifier()); 1213 1214 case Declarator::DK_Constructor: { 1215 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1216 Ty = Context.getCanonicalType(Ty); 1217 return Context.DeclarationNames.getCXXConstructorName(Ty); 1218 } 1219 1220 case Declarator::DK_Destructor: { 1221 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1222 Ty = Context.getCanonicalType(Ty); 1223 return Context.DeclarationNames.getCXXDestructorName(Ty); 1224 } 1225 1226 case Declarator::DK_Conversion: { 1227 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1228 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1229 Ty = Context.getCanonicalType(Ty); 1230 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1231 } 1232 1233 case Declarator::DK_Operator: 1234 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1235 return Context.DeclarationNames.getCXXOperatorName( 1236 D.getOverloadedOperator()); 1237 } 1238 1239 assert(false && "Unknown name kind"); 1240 return DeclarationName(); 1241} 1242 1243/// isNearlyMatchingFunction - Determine whether the C++ functions 1244/// Declaration and Definition are "nearly" matching. This heuristic 1245/// is used to improve diagnostics in the case where an out-of-line 1246/// function definition doesn't match any declaration within 1247/// the class or namespace. 1248static bool isNearlyMatchingFunction(ASTContext &Context, 1249 FunctionDecl *Declaration, 1250 FunctionDecl *Definition) { 1251 if (Declaration->param_size() != Definition->param_size()) 1252 return false; 1253 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1254 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1255 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1256 1257 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1258 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1259 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1260 return false; 1261 } 1262 1263 return true; 1264} 1265 1266Sema::DeclPtrTy 1267Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1268 DeclarationName Name = GetNameForDeclarator(D); 1269 1270 // All of these full declarators require an identifier. If it doesn't have 1271 // one, the ParsedFreeStandingDeclSpec action should be used. 1272 if (!Name) { 1273 if (!D.getInvalidType()) // Reject this if we think it is valid. 1274 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1275 diag::err_declarator_need_ident) 1276 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1277 return DeclPtrTy(); 1278 } 1279 1280 // The scope passed in may not be a decl scope. Zip up the scope tree until 1281 // we find one that is. 1282 while ((S->getFlags() & Scope::DeclScope) == 0 || 1283 (S->getFlags() & Scope::TemplateParamScope) != 0) 1284 S = S->getParent(); 1285 1286 DeclContext *DC; 1287 NamedDecl *PrevDecl; 1288 NamedDecl *New; 1289 bool InvalidDecl = false; 1290 1291 QualType R = GetTypeForDeclarator(D, S); 1292 if (R.isNull()) { 1293 InvalidDecl = true; 1294 R = Context.IntTy; 1295 } 1296 1297 // See if this is a redefinition of a variable in the same scope. 1298 if (D.getCXXScopeSpec().isInvalid()) { 1299 DC = CurContext; 1300 PrevDecl = 0; 1301 InvalidDecl = true; 1302 } else if (!D.getCXXScopeSpec().isSet()) { 1303 LookupNameKind NameKind = LookupOrdinaryName; 1304 1305 // If the declaration we're planning to build will be a function 1306 // or object with linkage, then look for another declaration with 1307 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1308 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1309 /* Do nothing*/; 1310 else if (R->isFunctionType()) { 1311 if (CurContext->isFunctionOrMethod()) 1312 NameKind = LookupRedeclarationWithLinkage; 1313 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1314 NameKind = LookupRedeclarationWithLinkage; 1315 1316 DC = CurContext; 1317 PrevDecl = LookupName(S, Name, NameKind, true, 1318 D.getDeclSpec().getStorageClassSpec() != 1319 DeclSpec::SCS_static, 1320 D.getIdentifierLoc()); 1321 } else { // Something like "int foo::x;" 1322 DC = computeDeclContext(D.getCXXScopeSpec()); 1323 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1324 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1325 1326 // C++ 7.3.1.2p2: 1327 // Members (including explicit specializations of templates) of a named 1328 // namespace can also be defined outside that namespace by explicit 1329 // qualification of the name being defined, provided that the entity being 1330 // defined was already declared in the namespace and the definition appears 1331 // after the point of declaration in a namespace that encloses the 1332 // declarations namespace. 1333 // 1334 // Note that we only check the context at this point. We don't yet 1335 // have enough information to make sure that PrevDecl is actually 1336 // the declaration we want to match. For example, given: 1337 // 1338 // class X { 1339 // void f(); 1340 // void f(float); 1341 // }; 1342 // 1343 // void X::f(int) { } // ill-formed 1344 // 1345 // In this case, PrevDecl will point to the overload set 1346 // containing the two f's declared in X, but neither of them 1347 // matches. 1348 1349 // First check whether we named the global scope. 1350 if (isa<TranslationUnitDecl>(DC)) { 1351 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1352 << Name << D.getCXXScopeSpec().getRange(); 1353 } else if (!CurContext->Encloses(DC)) { 1354 // The qualifying scope doesn't enclose the original declaration. 1355 // Emit diagnostic based on current scope. 1356 SourceLocation L = D.getIdentifierLoc(); 1357 SourceRange R = D.getCXXScopeSpec().getRange(); 1358 if (isa<FunctionDecl>(CurContext)) 1359 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1360 else 1361 Diag(L, diag::err_invalid_declarator_scope) 1362 << Name << cast<NamedDecl>(DC) << R; 1363 InvalidDecl = true; 1364 } 1365 } 1366 1367 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1368 // Maybe we will complain about the shadowed template parameter. 1369 InvalidDecl = InvalidDecl 1370 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1371 // Just pretend that we didn't see the previous declaration. 1372 PrevDecl = 0; 1373 } 1374 1375 // In C++, the previous declaration we find might be a tag type 1376 // (class or enum). In this case, the new declaration will hide the 1377 // tag type. Note that this does does not apply if we're declaring a 1378 // typedef (C++ [dcl.typedef]p4). 1379 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1380 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1381 PrevDecl = 0; 1382 1383 bool Redeclaration = false; 1384 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1385 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, 1386 InvalidDecl, Redeclaration); 1387 } else if (R->isFunctionType()) { 1388 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1389 IsFunctionDefinition, InvalidDecl, 1390 Redeclaration); 1391 } else { 1392 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, 1393 InvalidDecl, Redeclaration); 1394 } 1395 1396 if (New == 0) 1397 return DeclPtrTy(); 1398 1399 // If this has an identifier and is not an invalid redeclaration, 1400 // add it to the scope stack. 1401 if (Name && !(Redeclaration && InvalidDecl)) 1402 PushOnScopeChains(New, S); 1403 // If any semantic error occurred, mark the decl as invalid. 1404 if (D.getInvalidType() || InvalidDecl) 1405 New->setInvalidDecl(); 1406 1407 return DeclPtrTy::make(New); 1408} 1409 1410/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1411/// types into constant array types in certain situations which would otherwise 1412/// be errors (for GCC compatibility). 1413static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1414 ASTContext &Context, 1415 bool &SizeIsNegative) { 1416 // This method tries to turn a variable array into a constant 1417 // array even when the size isn't an ICE. This is necessary 1418 // for compatibility with code that depends on gcc's buggy 1419 // constant expression folding, like struct {char x[(int)(char*)2];} 1420 SizeIsNegative = false; 1421 1422 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1423 QualType Pointee = PTy->getPointeeType(); 1424 QualType FixedType = 1425 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1426 if (FixedType.isNull()) return FixedType; 1427 FixedType = Context.getPointerType(FixedType); 1428 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1429 return FixedType; 1430 } 1431 1432 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1433 if (!VLATy) 1434 return QualType(); 1435 // FIXME: We should probably handle this case 1436 if (VLATy->getElementType()->isVariablyModifiedType()) 1437 return QualType(); 1438 1439 Expr::EvalResult EvalResult; 1440 if (!VLATy->getSizeExpr() || 1441 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1442 !EvalResult.Val.isInt()) 1443 return QualType(); 1444 1445 llvm::APSInt &Res = EvalResult.Val.getInt(); 1446 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1447 return Context.getConstantArrayType(VLATy->getElementType(), 1448 Res, ArrayType::Normal, 0); 1449 1450 SizeIsNegative = true; 1451 return QualType(); 1452} 1453 1454/// \brief Register the given locally-scoped external C declaration so 1455/// that it can be found later for redeclarations 1456void 1457Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1458 Scope *S) { 1459 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1460 "Decl is not a locally-scoped decl!"); 1461 // Note that we have a locally-scoped external with this name. 1462 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1463 1464 if (!PrevDecl) 1465 return; 1466 1467 // If there was a previous declaration of this variable, it may be 1468 // in our identifier chain. Update the identifier chain with the new 1469 // declaration. 1470 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1471 // The previous declaration was found on the identifer resolver 1472 // chain, so remove it from its scope. 1473 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1474 S = S->getParent(); 1475 1476 if (S) 1477 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1478 } 1479} 1480 1481/// \brief Diagnose function specifiers on a declaration of an identifier that 1482/// does not identify a function. 1483void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1484 // FIXME: We should probably indicate the identifier in question to avoid 1485 // confusion for constructs like "inline int a(), b;" 1486 if (D.getDeclSpec().isInlineSpecified()) 1487 Diag(D.getDeclSpec().getInlineSpecLoc(), 1488 diag::err_inline_non_function); 1489 1490 if (D.getDeclSpec().isVirtualSpecified()) 1491 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1492 diag::err_virtual_non_function); 1493 1494 if (D.getDeclSpec().isExplicitSpecified()) 1495 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1496 diag::err_explicit_non_function); 1497} 1498 1499NamedDecl* 1500Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1501 QualType R, Decl* PrevDecl, bool& InvalidDecl, 1502 bool &Redeclaration) { 1503 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1504 if (D.getCXXScopeSpec().isSet()) { 1505 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1506 << D.getCXXScopeSpec().getRange(); 1507 InvalidDecl = true; 1508 // Pretend we didn't see the scope specifier. 1509 DC = 0; 1510 } 1511 1512 if (getLangOptions().CPlusPlus) { 1513 // Check that there are no default arguments (C++ only). 1514 CheckExtraCXXDefaultArguments(D); 1515 } 1516 1517 DiagnoseFunctionSpecifiers(D); 1518 1519 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1520 if (!NewTD) return 0; 1521 1522 // Handle attributes prior to checking for duplicates in MergeVarDecl 1523 ProcessDeclAttributes(NewTD, D); 1524 // Merge the decl with the existing one if appropriate. If the decl is 1525 // in an outer scope, it isn't the same thing. 1526 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1527 Redeclaration = true; 1528 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1529 InvalidDecl = true; 1530 } 1531 1532 if (S->getFnParent() == 0) { 1533 QualType T = NewTD->getUnderlyingType(); 1534 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1535 // then it shall have block scope. 1536 if (T->isVariablyModifiedType()) { 1537 bool SizeIsNegative; 1538 QualType FixedTy = 1539 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1540 if (!FixedTy.isNull()) { 1541 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1542 NewTD->setUnderlyingType(FixedTy); 1543 } else { 1544 if (SizeIsNegative) 1545 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1546 else if (T->isVariableArrayType()) 1547 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1548 else 1549 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1550 InvalidDecl = true; 1551 } 1552 } 1553 } 1554 return NewTD; 1555} 1556 1557/// \brief Determines whether the given declaration is an out-of-scope 1558/// previous declaration. 1559/// 1560/// This routine should be invoked when name lookup has found a 1561/// previous declaration (PrevDecl) that is not in the scope where a 1562/// new declaration by the same name is being introduced. If the new 1563/// declaration occurs in a local scope, previous declarations with 1564/// linkage may still be considered previous declarations (C99 1565/// 6.2.2p4-5, C++ [basic.link]p6). 1566/// 1567/// \param PrevDecl the previous declaration found by name 1568/// lookup 1569/// 1570/// \param DC the context in which the new declaration is being 1571/// declared. 1572/// 1573/// \returns true if PrevDecl is an out-of-scope previous declaration 1574/// for a new delcaration with the same name. 1575static bool 1576isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1577 ASTContext &Context) { 1578 if (!PrevDecl) 1579 return 0; 1580 1581 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1582 // case we need to check each of the overloaded functions. 1583 if (!PrevDecl->hasLinkage()) 1584 return false; 1585 1586 if (Context.getLangOptions().CPlusPlus) { 1587 // C++ [basic.link]p6: 1588 // If there is a visible declaration of an entity with linkage 1589 // having the same name and type, ignoring entities declared 1590 // outside the innermost enclosing namespace scope, the block 1591 // scope declaration declares that same entity and receives the 1592 // linkage of the previous declaration. 1593 DeclContext *OuterContext = DC->getLookupContext(); 1594 if (!OuterContext->isFunctionOrMethod()) 1595 // This rule only applies to block-scope declarations. 1596 return false; 1597 else { 1598 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1599 if (PrevOuterContext->isRecord()) 1600 // We found a member function: ignore it. 1601 return false; 1602 else { 1603 // Find the innermost enclosing namespace for the new and 1604 // previous declarations. 1605 while (!OuterContext->isFileContext()) 1606 OuterContext = OuterContext->getParent(); 1607 while (!PrevOuterContext->isFileContext()) 1608 PrevOuterContext = PrevOuterContext->getParent(); 1609 1610 // The previous declaration is in a different namespace, so it 1611 // isn't the same function. 1612 if (OuterContext->getPrimaryContext() != 1613 PrevOuterContext->getPrimaryContext()) 1614 return false; 1615 } 1616 } 1617 } 1618 1619 return true; 1620} 1621 1622NamedDecl* 1623Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1624 QualType R,NamedDecl* PrevDecl, bool& InvalidDecl, 1625 bool &Redeclaration) { 1626 DeclarationName Name = GetNameForDeclarator(D); 1627 1628 // Check that there are no default arguments (C++ only). 1629 if (getLangOptions().CPlusPlus) 1630 CheckExtraCXXDefaultArguments(D); 1631 1632 VarDecl *NewVD; 1633 VarDecl::StorageClass SC; 1634 switch (D.getDeclSpec().getStorageClassSpec()) { 1635 default: assert(0 && "Unknown storage class!"); 1636 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1637 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1638 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1639 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1640 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1641 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1642 case DeclSpec::SCS_mutable: 1643 // mutable can only appear on non-static class members, so it's always 1644 // an error here 1645 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1646 InvalidDecl = true; 1647 SC = VarDecl::None; 1648 break; 1649 } 1650 1651 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1652 if (!II) { 1653 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1654 << Name.getAsString(); 1655 return 0; 1656 } 1657 1658 DiagnoseFunctionSpecifiers(D); 1659 1660 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1661 if (!DC->isRecord() && S->getFnParent() == 0) { 1662 // C99 6.9p2: The storage-class specifiers auto and register shall not 1663 // appear in the declaration specifiers in an external declaration. 1664 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1665 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1666 InvalidDecl = true; 1667 } 1668 } 1669 if (DC->isRecord() && !CurContext->isRecord()) { 1670 // This is an out-of-line definition of a static data member. 1671 if (SC == VarDecl::Static) { 1672 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1673 diag::err_static_out_of_line) 1674 << CodeModificationHint::CreateRemoval( 1675 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1676 } else if (SC == VarDecl::None) 1677 SC = VarDecl::Static; 1678 } 1679 1680 // The variable can not 1681 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1682 II, R, SC, 1683 // FIXME: Move to DeclGroup... 1684 D.getDeclSpec().getSourceRange().getBegin()); 1685 NewVD->setThreadSpecified(ThreadSpecified); 1686 1687 // Set the lexical context. If the declarator has a C++ scope specifier, the 1688 // lexical context will be different from the semantic context. 1689 NewVD->setLexicalDeclContext(CurContext); 1690 1691 // Handle attributes prior to checking for duplicates in MergeVarDecl 1692 ProcessDeclAttributes(NewVD, D); 1693 1694 // Handle GNU asm-label extension (encoded as an attribute). 1695 if (Expr *E = (Expr*) D.getAsmLabel()) { 1696 // The parser guarantees this is a string. 1697 StringLiteral *SE = cast<StringLiteral>(E); 1698 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1699 SE->getByteLength()))); 1700 } 1701 1702 // If name lookup finds a previous declaration that is not in the 1703 // same scope as the new declaration, this may still be an 1704 // acceptable redeclaration. 1705 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1706 !(NewVD->hasLinkage() && 1707 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1708 PrevDecl = 0; 1709 1710 // Merge the decl with the existing one if appropriate. 1711 if (PrevDecl) { 1712 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1713 // The user tried to define a non-static data member 1714 // out-of-line (C++ [dcl.meaning]p1). 1715 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1716 << D.getCXXScopeSpec().getRange(); 1717 PrevDecl = 0; 1718 InvalidDecl = true; 1719 } 1720 } else if (D.getCXXScopeSpec().isSet()) { 1721 // No previous declaration in the qualifying scope. 1722 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1723 << Name << D.getCXXScopeSpec().getRange(); 1724 InvalidDecl = true; 1725 } 1726 1727 if (CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration)) 1728 InvalidDecl = true; 1729 1730 // If this is a locally-scoped extern C variable, update the map of 1731 // such variables. 1732 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1733 !InvalidDecl) 1734 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1735 1736 return NewVD; 1737} 1738 1739/// \brief Perform semantic checking on a newly-created variable 1740/// declaration. 1741/// 1742/// This routine performs all of the type-checking required for a 1743/// variable declaration once it has been build. It is used both to 1744/// check variables after they have been parsed and their declarators 1745/// have been translated into a declaration, and to check 1746/// 1747/// \returns true if an error was encountered, false otherwise. 1748bool Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1749 bool &Redeclaration) { 1750 bool Invalid = false; 1751 1752 QualType T = NewVD->getType(); 1753 1754 if (T->isObjCInterfaceType()) { 1755 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1756 Invalid = true; 1757 } 1758 1759 // The variable can not have an abstract class type. 1760 if (RequireNonAbstractType(NewVD->getLocation(), T, 1761 diag::err_abstract_type_in_decl, 1762 AbstractVariableType)) 1763 Invalid = true; 1764 1765 // Emit an error if an address space was applied to decl with local storage. 1766 // This includes arrays of objects with address space qualifiers, but not 1767 // automatic variables that point to other address spaces. 1768 // ISO/IEC TR 18037 S5.1.2 1769 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1770 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1771 Invalid = true; 1772 } 1773 1774 if (NewVD->hasLocalStorage() && T.isObjCGCWeak()) 1775 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1776 1777 bool isIllegalVLA = T->isVariableArrayType() && NewVD->hasGlobalStorage(); 1778 bool isIllegalVM = T->isVariablyModifiedType() && NewVD->hasLinkage(); 1779 if (isIllegalVLA || isIllegalVM) { 1780 bool SizeIsNegative; 1781 QualType FixedTy = 1782 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1783 if (!FixedTy.isNull()) { 1784 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1785 NewVD->setType(FixedTy); 1786 } else if (T->isVariableArrayType()) { 1787 Invalid = true; 1788 1789 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1790 // FIXME: This won't give the correct result for 1791 // int a[10][n]; 1792 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1793 1794 if (NewVD->isFileVarDecl()) 1795 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1796 << SizeRange; 1797 else if (NewVD->getStorageClass() == VarDecl::Static) 1798 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1799 << SizeRange; 1800 else 1801 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1802 << SizeRange; 1803 } else { 1804 Invalid = true; 1805 1806 if (NewVD->isFileVarDecl()) 1807 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1808 else 1809 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1810 } 1811 } 1812 1813 if (!PrevDecl && NewVD->isExternC(Context)) { 1814 // Since we did not find anything by this name and we're declaring 1815 // an extern "C" variable, look for a non-visible extern "C" 1816 // declaration with the same name. 1817 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1818 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1819 if (Pos != LocallyScopedExternalDecls.end()) 1820 PrevDecl = Pos->second; 1821 } 1822 1823 if (!Invalid && T->isVoidType() && !NewVD->hasExternalStorage()) { 1824 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1825 << T; 1826 Invalid = true; 1827 } 1828 1829 if (PrevDecl) { 1830 Redeclaration = true; 1831 if (MergeVarDecl(NewVD, PrevDecl)) 1832 Invalid = true; 1833 } 1834 1835 return NewVD->isInvalidDecl() || Invalid; 1836} 1837 1838NamedDecl* 1839Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1840 QualType R, NamedDecl* PrevDecl, 1841 bool IsFunctionDefinition, 1842 bool& InvalidDecl, bool &Redeclaration) { 1843 assert(R.getTypePtr()->isFunctionType()); 1844 1845 DeclarationName Name = GetNameForDeclarator(D); 1846 FunctionDecl::StorageClass SC = FunctionDecl::None; 1847 switch (D.getDeclSpec().getStorageClassSpec()) { 1848 default: assert(0 && "Unknown storage class!"); 1849 case DeclSpec::SCS_auto: 1850 case DeclSpec::SCS_register: 1851 case DeclSpec::SCS_mutable: 1852 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1853 diag::err_typecheck_sclass_func); 1854 InvalidDecl = true; 1855 break; 1856 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1857 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1858 case DeclSpec::SCS_static: { 1859 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1860 // C99 6.7.1p5: 1861 // The declaration of an identifier for a function that has 1862 // block scope shall have no explicit storage-class specifier 1863 // other than extern 1864 // See also (C++ [dcl.stc]p4). 1865 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1866 diag::err_static_block_func); 1867 SC = FunctionDecl::None; 1868 } else 1869 SC = FunctionDecl::Static; 1870 break; 1871 } 1872 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1873 } 1874 1875 bool isInline = D.getDeclSpec().isInlineSpecified(); 1876 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1877 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1878 1879 // Check that the return type is not an abstract class type. 1880 // For record types, this is done by the AbstractClassUsageDiagnoser once 1881 // the class has been completely parsed. 1882 if (!DC->isRecord() && 1883 RequireNonAbstractType(D.getIdentifierLoc(), 1884 R->getAsFunctionType()->getResultType(), 1885 diag::err_abstract_type_in_decl, 1886 AbstractReturnType)) 1887 InvalidDecl = true; 1888 1889 bool isVirtualOkay = false; 1890 FunctionDecl *NewFD; 1891 if (D.getKind() == Declarator::DK_Constructor) { 1892 // This is a C++ constructor declaration. 1893 assert(DC->isRecord() && 1894 "Constructors can only be declared in a member context"); 1895 1896 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1897 1898 // Create the new declaration 1899 NewFD = CXXConstructorDecl::Create(Context, 1900 cast<CXXRecordDecl>(DC), 1901 D.getIdentifierLoc(), Name, R, 1902 isExplicit, isInline, 1903 /*isImplicitlyDeclared=*/false); 1904 1905 if (InvalidDecl) 1906 NewFD->setInvalidDecl(); 1907 } else if (D.getKind() == Declarator::DK_Destructor) { 1908 // This is a C++ destructor declaration. 1909 if (DC->isRecord()) { 1910 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1911 1912 NewFD = CXXDestructorDecl::Create(Context, 1913 cast<CXXRecordDecl>(DC), 1914 D.getIdentifierLoc(), Name, R, 1915 isInline, 1916 /*isImplicitlyDeclared=*/false); 1917 1918 if (InvalidDecl) 1919 NewFD->setInvalidDecl(); 1920 1921 isVirtualOkay = true; 1922 } else { 1923 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1924 1925 // Create a FunctionDecl to satisfy the function definition parsing 1926 // code path. 1927 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1928 Name, R, SC, isInline, 1929 /*hasPrototype=*/true, 1930 // FIXME: Move to DeclGroup... 1931 D.getDeclSpec().getSourceRange().getBegin()); 1932 InvalidDecl = true; 1933 NewFD->setInvalidDecl(); 1934 } 1935 } else if (D.getKind() == Declarator::DK_Conversion) { 1936 if (!DC->isRecord()) { 1937 Diag(D.getIdentifierLoc(), 1938 diag::err_conv_function_not_member); 1939 return 0; 1940 } else { 1941 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1942 1943 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1944 D.getIdentifierLoc(), Name, R, 1945 isInline, isExplicit); 1946 1947 if (InvalidDecl) 1948 NewFD->setInvalidDecl(); 1949 1950 isVirtualOkay = true; 1951 } 1952 } else if (DC->isRecord()) { 1953 // This is a C++ method declaration. 1954 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1955 D.getIdentifierLoc(), Name, R, 1956 (SC == FunctionDecl::Static), isInline); 1957 1958 isVirtualOkay = (SC != FunctionDecl::Static); 1959 } else { 1960 // Determine whether the function was written with a 1961 // prototype. This true when: 1962 // - we're in C++ (where every function has a prototype), 1963 // - there is a prototype in the declarator, or 1964 // - the type R of the function is some kind of typedef or other reference 1965 // to a type name (which eventually refers to a function type). 1966 bool HasPrototype = 1967 getLangOptions().CPlusPlus || 1968 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 1969 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 1970 1971 NewFD = FunctionDecl::Create(Context, DC, 1972 D.getIdentifierLoc(), 1973 Name, R, SC, isInline, HasPrototype, 1974 // FIXME: Move to DeclGroup... 1975 D.getDeclSpec().getSourceRange().getBegin()); 1976 } 1977 1978 // Set the lexical context. If the declarator has a C++ 1979 // scope specifier, the lexical context will be different 1980 // from the semantic context. 1981 NewFD->setLexicalDeclContext(CurContext); 1982 1983 // C++ [dcl.fct.spec]p5: 1984 // The virtual specifier shall only be used in declarations of 1985 // nonstatic class member functions that appear within a 1986 // member-specification of a class declaration; see 10.3. 1987 // 1988 // FIXME: Checking the 'virtual' specifier is not sufficient. A 1989 // function is also virtual if it overrides an already virtual 1990 // function. This is important to do here because it's part of the 1991 // declaration. 1992 if (isVirtual && !InvalidDecl) { 1993 if (!isVirtualOkay) { 1994 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1995 diag::err_virtual_non_function); 1996 } else if (!CurContext->isRecord()) { 1997 // 'virtual' was specified outside of the class. 1998 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 1999 << CodeModificationHint::CreateRemoval( 2000 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2001 } else { 2002 // Okay: Add virtual to the method. 2003 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2004 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2005 CurClass->setAggregate(false); 2006 CurClass->setPOD(false); 2007 CurClass->setPolymorphic(true); 2008 } 2009 } 2010 2011 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2012 !CurContext->isRecord()) { 2013 // C++ [class.static]p1: 2014 // A data or function member of a class may be declared static 2015 // in a class definition, in which case it is a static member of 2016 // the class. 2017 2018 // Complain about the 'static' specifier if it's on an out-of-line 2019 // member function definition. 2020 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2021 diag::err_static_out_of_line) 2022 << CodeModificationHint::CreateRemoval( 2023 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2024 } 2025 2026 // Handle GNU asm-label extension (encoded as an attribute). 2027 if (Expr *E = (Expr*) D.getAsmLabel()) { 2028 // The parser guarantees this is a string. 2029 StringLiteral *SE = cast<StringLiteral>(E); 2030 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2031 SE->getByteLength()))); 2032 } 2033 2034 // Copy the parameter declarations from the declarator D to 2035 // the function declaration NewFD, if they are available. 2036 if (D.getNumTypeObjects() > 0) { 2037 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2038 2039 // Create Decl objects for each parameter, adding them to the 2040 // FunctionDecl. 2041 llvm::SmallVector<ParmVarDecl*, 16> Params; 2042 2043 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2044 // function that takes no arguments, not a function that takes a 2045 // single void argument. 2046 // We let through "const void" here because Sema::GetTypeForDeclarator 2047 // already checks for that case. 2048 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2049 FTI.ArgInfo[0].Param && 2050 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2051 // empty arg list, don't push any params. 2052 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2053 2054 // In C++, the empty parameter-type-list must be spelled "void"; a 2055 // typedef of void is not permitted. 2056 if (getLangOptions().CPlusPlus && 2057 Param->getType().getUnqualifiedType() != Context.VoidTy) { 2058 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2059 } 2060 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2061 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2062 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2063 } 2064 2065 NewFD->setParams(Context, &Params[0], Params.size()); 2066 } else if (R->getAsTypedefType()) { 2067 // When we're declaring a function with a typedef, as in the 2068 // following example, we'll need to synthesize (unnamed) 2069 // parameters for use in the declaration. 2070 // 2071 // @code 2072 // typedef void fn(int); 2073 // fn f; 2074 // @endcode 2075 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 2076 if (!FT) { 2077 // This is a typedef of a function with no prototype, so we 2078 // don't need to do anything. 2079 } else if ((FT->getNumArgs() == 0) || 2080 (FT->getNumArgs() == 1 && !FT->isVariadic() && 2081 FT->getArgType(0)->isVoidType())) { 2082 // This is a zero-argument function. We don't need to do anything. 2083 } else { 2084 // Synthesize a parameter for each argument type. 2085 llvm::SmallVector<ParmVarDecl*, 16> Params; 2086 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 2087 ArgType != FT->arg_type_end(); ++ArgType) { 2088 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2089 SourceLocation(), 0, 2090 *ArgType, VarDecl::None, 2091 0); 2092 Param->setImplicit(); 2093 Params.push_back(Param); 2094 } 2095 2096 NewFD->setParams(Context, &Params[0], Params.size()); 2097 } 2098 } 2099 2100 // If name lookup finds a previous declaration that is not in the 2101 // same scope as the new declaration, this may still be an 2102 // acceptable redeclaration. 2103 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2104 !(NewFD->hasLinkage() && 2105 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2106 PrevDecl = 0; 2107 2108 // Perform semantic checking on the function declaration. 2109 bool OverloadableAttrRequired = false; // FIXME: HACK! 2110 if (CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2111 /*FIXME:*/OverloadableAttrRequired)) 2112 InvalidDecl = true; 2113 2114 if (D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2115 // An out-of-line member function declaration must also be a 2116 // definition (C++ [dcl.meaning]p1). 2117 if (!IsFunctionDefinition) { 2118 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2119 << D.getCXXScopeSpec().getRange(); 2120 InvalidDecl = true; 2121 } else if (!Redeclaration) { 2122 // The user tried to provide an out-of-line definition for a 2123 // function that is a member of a class or namespace, but there 2124 // was no such member function declared (C++ [class.mfct]p2, 2125 // C++ [namespace.memdef]p2). For example: 2126 // 2127 // class X { 2128 // void f() const; 2129 // }; 2130 // 2131 // void X::f() { } // ill-formed 2132 // 2133 // Complain about this problem, and attempt to suggest close 2134 // matches (e.g., those that differ only in cv-qualifiers and 2135 // whether the parameter types are references). 2136 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2137 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2138 InvalidDecl = true; 2139 2140 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2141 true); 2142 assert(!Prev.isAmbiguous() && 2143 "Cannot have an ambiguity in previous-declaration lookup"); 2144 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2145 Func != FuncEnd; ++Func) { 2146 if (isa<FunctionDecl>(*Func) && 2147 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2148 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2149 } 2150 2151 PrevDecl = 0; 2152 } 2153 } 2154 2155 // Handle attributes. We need to have merged decls when handling attributes 2156 // (for example to check for conflicts, etc). 2157 // FIXME: This needs to happen before we merge declarations. Then, 2158 // let attribute merging cope with attribute conflicts. 2159 ProcessDeclAttributes(NewFD, D); 2160 AddKnownFunctionAttributes(NewFD); 2161 2162 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2163 // If a function name is overloadable in C, then every function 2164 // with that name must be marked "overloadable". 2165 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2166 << Redeclaration << NewFD; 2167 if (PrevDecl) 2168 Diag(PrevDecl->getLocation(), 2169 diag::note_attribute_overloadable_prev_overload); 2170 NewFD->addAttr(::new (Context) OverloadableAttr()); 2171 } 2172 2173 // If this is a locally-scoped extern C function, update the 2174 // map of such names. 2175 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2176 && !InvalidDecl) 2177 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2178 2179 return NewFD; 2180} 2181 2182/// \brief Perform semantic checking of a new function declaration. 2183/// 2184/// Performs semantic analysis of the new function declaration 2185/// NewFD. This routine performs all semantic checking that does not 2186/// require the actual declarator involved in the declaration, and is 2187/// used both for the declaration of functions as they are parsed 2188/// (called via ActOnDeclarator) and for the declaration of functions 2189/// that have been instantiated via C++ template instantiation (called 2190/// via InstantiateDecl). 2191/// 2192/// \returns true if there was an error, false otherwise. 2193bool Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2194 bool &Redeclaration, 2195 bool &OverloadableAttrRequired) { 2196 bool InvalidDecl = false; 2197 2198 // Semantic checking for this function declaration (in isolation). 2199 if (getLangOptions().CPlusPlus) { 2200 // C++-specific checks. 2201 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 2202 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 2203 else if (isa<CXXDestructorDecl>(NewFD)) { 2204 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2205 Record->setUserDeclaredDestructor(true); 2206 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2207 // user-defined destructor. 2208 Record->setPOD(false); 2209 } else if (CXXConversionDecl *Conversion 2210 = dyn_cast<CXXConversionDecl>(NewFD)) 2211 ActOnConversionDeclarator(Conversion); 2212 2213 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2214 if (NewFD->isOverloadedOperator() && 2215 CheckOverloadedOperatorDeclaration(NewFD)) 2216 InvalidDecl = true; 2217 } 2218 2219 // Check for a previous declaration of this name. 2220 if (!PrevDecl && NewFD->isExternC(Context)) { 2221 // Since we did not find anything by this name and we're declaring 2222 // an extern "C" function, look for a non-visible extern "C" 2223 // declaration with the same name. 2224 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2225 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2226 if (Pos != LocallyScopedExternalDecls.end()) 2227 PrevDecl = Pos->second; 2228 } 2229 2230 // Merge or overload the declaration with an existing declaration of 2231 // the same name, if appropriate. 2232 if (PrevDecl) { 2233 // Determine whether NewFD is an overload of PrevDecl or 2234 // a declaration that requires merging. If it's an overload, 2235 // there's no more work to do here; we'll just add the new 2236 // function to the scope. 2237 OverloadedFunctionDecl::function_iterator MatchedDecl; 2238 2239 if (!getLangOptions().CPlusPlus && 2240 AllowOverloadingOfFunction(PrevDecl, Context)) { 2241 OverloadableAttrRequired = true; 2242 2243 // Functions marked "overloadable" must have a prototype (that 2244 // we can't get through declaration merging). 2245 if (!NewFD->getType()->getAsFunctionProtoType()) { 2246 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2247 << NewFD; 2248 InvalidDecl = true; 2249 Redeclaration = true; 2250 2251 // Turn this into a variadic function with no parameters. 2252 QualType R = Context.getFunctionType( 2253 NewFD->getType()->getAsFunctionType()->getResultType(), 2254 0, 0, true, 0); 2255 NewFD->setType(R); 2256 } 2257 } 2258 2259 if (PrevDecl && 2260 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2261 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2262 Redeclaration = true; 2263 Decl *OldDecl = PrevDecl; 2264 2265 // If PrevDecl was an overloaded function, extract the 2266 // FunctionDecl that matched. 2267 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2268 OldDecl = *MatchedDecl; 2269 2270 // NewFD and OldDecl represent declarations that need to be 2271 // merged. 2272 if (MergeFunctionDecl(NewFD, OldDecl)) 2273 InvalidDecl = true; 2274 2275 if (!InvalidDecl) 2276 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2277 } 2278 } 2279 2280 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) { 2281 // In C++, check default arguments now that we have merged decls. Unless 2282 // the lexical context is the class, because in this case this is done 2283 // during delayed parsing anyway. 2284 CheckCXXDefaultArguments(NewFD); 2285 } 2286 2287 return InvalidDecl || NewFD->isInvalidDecl(); 2288} 2289 2290bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2291 // FIXME: Need strict checking. In C89, we need to check for 2292 // any assignment, increment, decrement, function-calls, or 2293 // commas outside of a sizeof. In C99, it's the same list, 2294 // except that the aforementioned are allowed in unevaluated 2295 // expressions. Everything else falls under the 2296 // "may accept other forms of constant expressions" exception. 2297 // (We never end up here for C++, so the constant expression 2298 // rules there don't matter.) 2299 if (Init->isConstantInitializer(Context)) 2300 return false; 2301 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2302 << Init->getSourceRange(); 2303 return true; 2304} 2305 2306void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2307 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2308} 2309 2310/// AddInitializerToDecl - Adds the initializer Init to the 2311/// declaration dcl. If DirectInit is true, this is C++ direct 2312/// initialization rather than copy initialization. 2313void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2314 Decl *RealDecl = dcl.getAs<Decl>(); 2315 // If there is no declaration, there was an error parsing it. Just ignore 2316 // the initializer. 2317 if (RealDecl == 0) 2318 return; 2319 2320 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2321 // With declarators parsed the way they are, the parser cannot 2322 // distinguish between a normal initializer and a pure-specifier. 2323 // Thus this grotesque test. 2324 IntegerLiteral *IL; 2325 Expr *Init = static_cast<Expr *>(init.get()); 2326 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2327 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2328 if (Method->isVirtual()) { 2329 Method->setPure(); 2330 2331 // A class is abstract if at least one function is pure virtual. 2332 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2333 } else if (!Method->isInvalidDecl()) { 2334 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2335 << Method->getDeclName() << Init->getSourceRange(); 2336 Method->setInvalidDecl(); 2337 } 2338 } else { 2339 Diag(Method->getLocation(), diag::err_member_function_initialization) 2340 << Method->getDeclName() << Init->getSourceRange(); 2341 Method->setInvalidDecl(); 2342 } 2343 return; 2344 } 2345 2346 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2347 if (!VDecl) { 2348 if (getLangOptions().CPlusPlus && 2349 RealDecl->getLexicalDeclContext()->isRecord() && 2350 isa<NamedDecl>(RealDecl)) 2351 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2352 << cast<NamedDecl>(RealDecl)->getDeclName(); 2353 else 2354 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2355 RealDecl->setInvalidDecl(); 2356 return; 2357 } 2358 2359 const VarDecl *Def = 0; 2360 if (VDecl->getDefinition(Def)) { 2361 Diag(VDecl->getLocation(), diag::err_redefinition) 2362 << VDecl->getDeclName(); 2363 Diag(Def->getLocation(), diag::note_previous_definition); 2364 VDecl->setInvalidDecl(); 2365 return; 2366 } 2367 2368 // Take ownership of the expression, now that we're sure we have somewhere 2369 // to put it. 2370 Expr *Init = static_cast<Expr *>(init.release()); 2371 assert(Init && "missing initializer"); 2372 2373 // Get the decls type and save a reference for later, since 2374 // CheckInitializerTypes may change it. 2375 QualType DclT = VDecl->getType(), SavT = DclT; 2376 if (VDecl->isBlockVarDecl()) { 2377 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2378 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2379 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2380 VDecl->setInvalidDecl(); 2381 } else if (!VDecl->isInvalidDecl()) { 2382 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2383 VDecl->getDeclName(), DirectInit)) 2384 VDecl->setInvalidDecl(); 2385 2386 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2387 // Don't check invalid declarations to avoid emitting useless diagnostics. 2388 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2389 if (SC == VarDecl::Static) // C99 6.7.8p4. 2390 CheckForConstantInitializer(Init, DclT); 2391 } 2392 } 2393 } else if (VDecl->isStaticDataMember() && 2394 VDecl->getLexicalDeclContext()->isRecord()) { 2395 // This is an in-class initialization for a static data member, e.g., 2396 // 2397 // struct S { 2398 // static const int value = 17; 2399 // }; 2400 2401 // Attach the initializer 2402 VDecl->setInit(Init); 2403 2404 // C++ [class.mem]p4: 2405 // A member-declarator can contain a constant-initializer only 2406 // if it declares a static member (9.4) of const integral or 2407 // const enumeration type, see 9.4.2. 2408 QualType T = VDecl->getType(); 2409 if (!T->isDependentType() && 2410 (!Context.getCanonicalType(T).isConstQualified() || 2411 !T->isIntegralType())) { 2412 Diag(VDecl->getLocation(), diag::err_member_initialization) 2413 << VDecl->getDeclName() << Init->getSourceRange(); 2414 VDecl->setInvalidDecl(); 2415 } else { 2416 // C++ [class.static.data]p4: 2417 // If a static data member is of const integral or const 2418 // enumeration type, its declaration in the class definition 2419 // can specify a constant-initializer which shall be an 2420 // integral constant expression (5.19). 2421 if (!Init->isTypeDependent() && 2422 !Init->getType()->isIntegralType()) { 2423 // We have a non-dependent, non-integral or enumeration type. 2424 Diag(Init->getSourceRange().getBegin(), 2425 diag::err_in_class_initializer_non_integral_type) 2426 << Init->getType() << Init->getSourceRange(); 2427 VDecl->setInvalidDecl(); 2428 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2429 // Check whether the expression is a constant expression. 2430 llvm::APSInt Value; 2431 SourceLocation Loc; 2432 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2433 Diag(Loc, diag::err_in_class_initializer_non_constant) 2434 << Init->getSourceRange(); 2435 VDecl->setInvalidDecl(); 2436 } else if (!VDecl->getType()->isDependentType()) 2437 ImpCastExprToType(Init, VDecl->getType()); 2438 } 2439 } 2440 } else if (VDecl->isFileVarDecl()) { 2441 if (VDecl->getStorageClass() == VarDecl::Extern) 2442 Diag(VDecl->getLocation(), diag::warn_extern_init); 2443 if (!VDecl->isInvalidDecl()) 2444 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2445 VDecl->getDeclName(), DirectInit)) 2446 VDecl->setInvalidDecl(); 2447 2448 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2449 // Don't check invalid declarations to avoid emitting useless diagnostics. 2450 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2451 // C99 6.7.8p4. All file scoped initializers need to be constant. 2452 CheckForConstantInitializer(Init, DclT); 2453 } 2454 } 2455 // If the type changed, it means we had an incomplete type that was 2456 // completed by the initializer. For example: 2457 // int ary[] = { 1, 3, 5 }; 2458 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2459 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2460 VDecl->setType(DclT); 2461 Init->setType(DclT); 2462 } 2463 2464 // Attach the initializer to the decl. 2465 VDecl->setInit(Init); 2466 return; 2467} 2468 2469void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2470 Decl *RealDecl = dcl.getAs<Decl>(); 2471 2472 // If there is no declaration, there was an error parsing it. Just ignore it. 2473 if (RealDecl == 0) 2474 return; 2475 2476 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2477 QualType Type = Var->getType(); 2478 // C++ [dcl.init.ref]p3: 2479 // The initializer can be omitted for a reference only in a 2480 // parameter declaration (8.3.5), in the declaration of a 2481 // function return type, in the declaration of a class member 2482 // within its class declaration (9.2), and where the extern 2483 // specifier is explicitly used. 2484 if (Type->isReferenceType() && 2485 Var->getStorageClass() != VarDecl::Extern && 2486 Var->getStorageClass() != VarDecl::PrivateExtern) { 2487 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2488 << Var->getDeclName() 2489 << SourceRange(Var->getLocation(), Var->getLocation()); 2490 Var->setInvalidDecl(); 2491 return; 2492 } 2493 2494 // C++ [dcl.init]p9: 2495 // 2496 // If no initializer is specified for an object, and the object 2497 // is of (possibly cv-qualified) non-POD class type (or array 2498 // thereof), the object shall be default-initialized; if the 2499 // object is of const-qualified type, the underlying class type 2500 // shall have a user-declared default constructor. 2501 if (getLangOptions().CPlusPlus) { 2502 QualType InitType = Type; 2503 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2504 InitType = Array->getElementType(); 2505 if (Var->getStorageClass() != VarDecl::Extern && 2506 Var->getStorageClass() != VarDecl::PrivateExtern && 2507 InitType->isRecordType()) { 2508 const CXXConstructorDecl *Constructor = 0; 2509 if (!RequireCompleteType(Var->getLocation(), InitType, 2510 diag::err_invalid_incomplete_type_use)) 2511 Constructor 2512 = PerformInitializationByConstructor(InitType, 0, 0, 2513 Var->getLocation(), 2514 SourceRange(Var->getLocation(), 2515 Var->getLocation()), 2516 Var->getDeclName(), 2517 IK_Default); 2518 if (!Constructor) 2519 Var->setInvalidDecl(); 2520 } 2521 } 2522 2523#if 0 2524 // FIXME: Temporarily disabled because we are not properly parsing 2525 // linkage specifications on declarations, e.g., 2526 // 2527 // extern "C" const CGPoint CGPointerZero; 2528 // 2529 // C++ [dcl.init]p9: 2530 // 2531 // If no initializer is specified for an object, and the 2532 // object is of (possibly cv-qualified) non-POD class type (or 2533 // array thereof), the object shall be default-initialized; if 2534 // the object is of const-qualified type, the underlying class 2535 // type shall have a user-declared default 2536 // constructor. Otherwise, if no initializer is specified for 2537 // an object, the object and its subobjects, if any, have an 2538 // indeterminate initial value; if the object or any of its 2539 // subobjects are of const-qualified type, the program is 2540 // ill-formed. 2541 // 2542 // This isn't technically an error in C, so we don't diagnose it. 2543 // 2544 // FIXME: Actually perform the POD/user-defined default 2545 // constructor check. 2546 if (getLangOptions().CPlusPlus && 2547 Context.getCanonicalType(Type).isConstQualified() && 2548 Var->getStorageClass() != VarDecl::Extern) 2549 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2550 << Var->getName() 2551 << SourceRange(Var->getLocation(), Var->getLocation()); 2552#endif 2553 } 2554} 2555 2556Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2557 unsigned NumDecls) { 2558 llvm::SmallVector<Decl*, 8> Decls; 2559 2560 for (unsigned i = 0; i != NumDecls; ++i) 2561 if (Decl *D = Group[i].getAs<Decl>()) 2562 Decls.push_back(D); 2563 2564 // Perform semantic analysis that depends on having fully processed both 2565 // the declarator and initializer. 2566 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2567 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2568 if (!IDecl) 2569 continue; 2570 QualType T = IDecl->getType(); 2571 2572 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2573 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2574 if (IDecl->isBlockVarDecl() && 2575 IDecl->getStorageClass() != VarDecl::Extern) { 2576 if (!IDecl->isInvalidDecl() && 2577 RequireCompleteType(IDecl->getLocation(), T, 2578 diag::err_typecheck_decl_incomplete_type)) 2579 IDecl->setInvalidDecl(); 2580 } 2581 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2582 // object that has file scope without an initializer, and without a 2583 // storage-class specifier or with the storage-class specifier "static", 2584 // constitutes a tentative definition. Note: A tentative definition with 2585 // external linkage is valid (C99 6.2.2p5). 2586 if (IDecl->isTentativeDefinition(Context)) { 2587 QualType CheckType = T; 2588 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2589 2590 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2591 if (ArrayT) { 2592 CheckType = ArrayT->getElementType(); 2593 DiagID = diag::err_illegal_decl_array_incomplete_type; 2594 } 2595 2596 if (IDecl->isInvalidDecl()) { 2597 // Do nothing with invalid declarations 2598 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2599 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2600 // C99 6.9.2p3: If the declaration of an identifier for an object is 2601 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2602 // declared type shall not be an incomplete type. 2603 IDecl->setInvalidDecl(); 2604 } 2605 } 2606 } 2607 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2608 &Decls[0], NumDecls)); 2609} 2610 2611 2612/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2613/// to introduce parameters into function prototype scope. 2614Sema::DeclPtrTy 2615Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2616 const DeclSpec &DS = D.getDeclSpec(); 2617 2618 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2619 VarDecl::StorageClass StorageClass = VarDecl::None; 2620 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2621 StorageClass = VarDecl::Register; 2622 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2623 Diag(DS.getStorageClassSpecLoc(), 2624 diag::err_invalid_storage_class_in_func_decl); 2625 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2626 } 2627 if (DS.isThreadSpecified()) { 2628 Diag(DS.getThreadSpecLoc(), 2629 diag::err_invalid_storage_class_in_func_decl); 2630 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2631 } 2632 DiagnoseFunctionSpecifiers(D); 2633 2634 // Check that there are no default arguments inside the type of this 2635 // parameter (C++ only). 2636 if (getLangOptions().CPlusPlus) 2637 CheckExtraCXXDefaultArguments(D); 2638 2639 // In this context, we *do not* check D.getInvalidType(). If the declarator 2640 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2641 // though it will not reflect the user specified type. 2642 QualType parmDeclType = GetTypeForDeclarator(D, S); 2643 2644 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2645 2646 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2647 // Can this happen for params? We already checked that they don't conflict 2648 // among each other. Here they can only shadow globals, which is ok. 2649 IdentifierInfo *II = D.getIdentifier(); 2650 if (II) { 2651 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2652 if (PrevDecl->isTemplateParameter()) { 2653 // Maybe we will complain about the shadowed template parameter. 2654 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2655 // Just pretend that we didn't see the previous declaration. 2656 PrevDecl = 0; 2657 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2658 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2659 2660 // Recover by removing the name 2661 II = 0; 2662 D.SetIdentifier(0, D.getIdentifierLoc()); 2663 } 2664 } 2665 } 2666 2667 // Parameters can not be abstract class types. 2668 // For record types, this is done by the AbstractClassUsageDiagnoser once 2669 // the class has been completely parsed. 2670 if (!CurContext->isRecord() && 2671 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2672 diag::err_abstract_type_in_decl, 2673 AbstractParamType)) 2674 D.setInvalidType(true); 2675 2676 QualType T = adjustParameterType(parmDeclType); 2677 2678 ParmVarDecl *New; 2679 if (T == parmDeclType) // parameter type did not need adjustment 2680 New = ParmVarDecl::Create(Context, CurContext, 2681 D.getIdentifierLoc(), II, 2682 parmDeclType, StorageClass, 2683 0); 2684 else // keep track of both the adjusted and unadjusted types 2685 New = OriginalParmVarDecl::Create(Context, CurContext, 2686 D.getIdentifierLoc(), II, T, 2687 parmDeclType, StorageClass, 0); 2688 2689 if (D.getInvalidType()) 2690 New->setInvalidDecl(); 2691 2692 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2693 if (D.getCXXScopeSpec().isSet()) { 2694 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2695 << D.getCXXScopeSpec().getRange(); 2696 New->setInvalidDecl(); 2697 } 2698 // Parameter declarators cannot be interface types. All ObjC objects are 2699 // passed by reference. 2700 if (T->isObjCInterfaceType()) { 2701 Diag(D.getIdentifierLoc(), diag::err_object_cannot_be_by_value) 2702 << "passed"; 2703 New->setInvalidDecl(); 2704 } 2705 2706 // Add the parameter declaration into this scope. 2707 S->AddDecl(DeclPtrTy::make(New)); 2708 if (II) 2709 IdResolver.AddDecl(New); 2710 2711 ProcessDeclAttributes(New, D); 2712 return DeclPtrTy::make(New); 2713} 2714 2715void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2716 SourceLocation LocAfterDecls) { 2717 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2718 "Not a function declarator!"); 2719 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2720 2721 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2722 // for a K&R function. 2723 if (!FTI.hasPrototype) { 2724 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2725 --i; 2726 if (FTI.ArgInfo[i].Param == 0) { 2727 std::string Code = " int "; 2728 Code += FTI.ArgInfo[i].Ident->getName(); 2729 Code += ";\n"; 2730 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2731 << FTI.ArgInfo[i].Ident 2732 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2733 2734 // Implicitly declare the argument as type 'int' for lack of a better 2735 // type. 2736 DeclSpec DS; 2737 const char* PrevSpec; // unused 2738 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2739 PrevSpec); 2740 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2741 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2742 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2743 } 2744 } 2745 } 2746} 2747 2748Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2749 Declarator &D) { 2750 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2751 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2752 "Not a function declarator!"); 2753 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2754 2755 if (FTI.hasPrototype) { 2756 // FIXME: Diagnose arguments without names in C. 2757 } 2758 2759 Scope *ParentScope = FnBodyScope->getParent(); 2760 2761 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2762 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2763} 2764 2765Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2766 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2767 2768 // See if this is a redefinition. 2769 const FunctionDecl *Definition; 2770 if (FD->getBody(Definition)) { 2771 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2772 Diag(Definition->getLocation(), diag::note_previous_definition); 2773 } 2774 2775 // Builtin functions cannot be defined. 2776 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2777 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2778 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2779 FD->setInvalidDecl(); 2780 } 2781 } 2782 2783 // The return type of a function definition must be complete 2784 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2785 QualType ResultType = FD->getResultType(); 2786 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2787 RequireCompleteType(FD->getLocation(), ResultType, 2788 diag::err_func_def_incomplete_result)) 2789 FD->setInvalidDecl(); 2790 2791 // GNU warning -Wmissing-prototypes: 2792 // Warn if a global function is defined without a previous 2793 // prototype declaration. This warning is issued even if the 2794 // definition itself provides a prototype. The aim is to detect 2795 // global functions that fail to be declared in header files. 2796 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD)) { 2797 bool MissingPrototype = true; 2798 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2799 Prev; Prev = Prev->getPreviousDeclaration()) { 2800 // Ignore any declarations that occur in function or method 2801 // scope, because they aren't visible from the header. 2802 if (Prev->getDeclContext()->isFunctionOrMethod()) 2803 continue; 2804 2805 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2806 break; 2807 } 2808 2809 if (MissingPrototype) 2810 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2811 } 2812 2813 PushDeclContext(FnBodyScope, FD); 2814 2815 // Check the validity of our function parameters 2816 CheckParmsForFunctionDef(FD); 2817 2818 // Introduce our parameters into the function scope 2819 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2820 ParmVarDecl *Param = FD->getParamDecl(p); 2821 Param->setOwningFunction(FD); 2822 2823 // If this has an identifier, add it to the scope stack. 2824 if (Param->getIdentifier()) 2825 PushOnScopeChains(Param, FnBodyScope); 2826 } 2827 2828 // Checking attributes of current function definition 2829 // dllimport attribute. 2830 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2831 // dllimport attribute cannot be applied to definition. 2832 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2833 Diag(FD->getLocation(), 2834 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2835 << "dllimport"; 2836 FD->setInvalidDecl(); 2837 return DeclPtrTy::make(FD); 2838 } else { 2839 // If a symbol previously declared dllimport is later defined, the 2840 // attribute is ignored in subsequent references, and a warning is 2841 // emitted. 2842 Diag(FD->getLocation(), 2843 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2844 << FD->getNameAsCString() << "dllimport"; 2845 } 2846 } 2847 return DeclPtrTy::make(FD); 2848} 2849 2850static bool StatementCreatesScope(Stmt* S) { 2851 bool result = false; 2852 if (DeclStmt* DS = dyn_cast<DeclStmt>(S)) { 2853 for (DeclStmt::decl_iterator i = DS->decl_begin(); 2854 i != DS->decl_end(); ++i) { 2855 if (VarDecl* D = dyn_cast<VarDecl>(*i)) { 2856 result |= D->getType()->isVariablyModifiedType(); 2857 result |= !!D->getAttr<CleanupAttr>(); 2858 } else if (TypedefDecl* D = dyn_cast<TypedefDecl>(*i)) { 2859 result |= D->getUnderlyingType()->isVariablyModifiedType(); 2860 } 2861 } 2862 } 2863 2864 return result; 2865} 2866 2867void Sema::RecursiveCalcLabelScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2868 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2869 std::vector<void*>& ScopeStack, 2870 Stmt* CurStmt, 2871 Stmt* ParentCompoundStmt) { 2872 for (Stmt::child_iterator i = CurStmt->child_begin(); 2873 i != CurStmt->child_end(); ++i) { 2874 if (!*i) continue; 2875 if (StatementCreatesScope(*i)) { 2876 ScopeStack.push_back(*i); 2877 PopScopeMap[*i] = ParentCompoundStmt; 2878 } else if (isa<LabelStmt>(CurStmt)) { 2879 LabelScopeMap[CurStmt] = ScopeStack.size() ? ScopeStack.back() : 0; 2880 } 2881 if (isa<DeclStmt>(*i)) continue; 2882 Stmt* CurCompound = isa<CompoundStmt>(*i) ? *i : ParentCompoundStmt; 2883 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, 2884 *i, CurCompound); 2885 } 2886 2887 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2888 ScopeStack.pop_back(); 2889 } 2890} 2891 2892void Sema::RecursiveCalcJumpScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2893 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2894 llvm::DenseMap<Stmt*, void*>& GotoScopeMap, 2895 std::vector<void*>& ScopeStack, 2896 Stmt* CurStmt) { 2897 for (Stmt::child_iterator i = CurStmt->child_begin(); 2898 i != CurStmt->child_end(); ++i) { 2899 if (!*i) continue; 2900 if (StatementCreatesScope(*i)) { 2901 ScopeStack.push_back(*i); 2902 } else if (GotoStmt* GS = dyn_cast<GotoStmt>(*i)) { 2903 void* LScope = LabelScopeMap[GS->getLabel()]; 2904 if (LScope) { 2905 bool foundScopeInStack = false; 2906 for (unsigned i = ScopeStack.size(); i > 0; --i) { 2907 if (LScope == ScopeStack[i-1]) { 2908 foundScopeInStack = true; 2909 break; 2910 } 2911 } 2912 if (!foundScopeInStack) { 2913 Diag(GS->getSourceRange().getBegin(), diag::err_goto_into_scope); 2914 } 2915 } 2916 } 2917 if (isa<DeclStmt>(*i)) continue; 2918 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, 2919 ScopeStack, *i); 2920 } 2921 2922 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2923 ScopeStack.pop_back(); 2924 } 2925} 2926 2927Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 2928 Decl *dcl = D.getAs<Decl>(); 2929 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2930 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2931 FD->setBody(cast<CompoundStmt>(Body)); 2932 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2933 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2934 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2935 MD->setBody(cast<CompoundStmt>(Body)); 2936 } else { 2937 Body->Destroy(Context); 2938 return DeclPtrTy(); 2939 } 2940 PopDeclContext(); 2941 // Verify and clean out per-function state. 2942 2943 bool HaveLabels = !LabelMap.empty(); 2944 // Check goto/label use. 2945 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2946 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2947 // Verify that we have no forward references left. If so, there was a goto 2948 // or address of a label taken, but no definition of it. Label fwd 2949 // definitions are indicated with a null substmt. 2950 if (I->second->getSubStmt() == 0) { 2951 LabelStmt *L = I->second; 2952 // Emit error. 2953 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2954 2955 // At this point, we have gotos that use the bogus label. Stitch it into 2956 // the function body so that they aren't leaked and that the AST is well 2957 // formed. 2958 if (Body) { 2959#if 0 2960 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2961 // and the AST is malformed anyway. We should just blow away 'L'. 2962 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2963 cast<CompoundStmt>(Body)->push_back(L); 2964#else 2965 L->Destroy(Context); 2966#endif 2967 } else { 2968 // The whole function wasn't parsed correctly, just delete this. 2969 L->Destroy(Context); 2970 } 2971 } 2972 } 2973 LabelMap.clear(); 2974 2975 if (!Body) return D; 2976 2977 if (HaveLabels) { 2978 llvm::DenseMap<Stmt*, void*> LabelScopeMap; 2979 llvm::DenseMap<void*, Stmt*> PopScopeMap; 2980 llvm::DenseMap<Stmt*, void*> GotoScopeMap; 2981 std::vector<void*> ScopeStack; 2982 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, Body, Body); 2983 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, ScopeStack, Body); 2984 } 2985 2986 return D; 2987} 2988 2989/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2990/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2991NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2992 IdentifierInfo &II, Scope *S) { 2993 // Before we produce a declaration for an implicitly defined 2994 // function, see whether there was a locally-scoped declaration of 2995 // this name as a function or variable. If so, use that 2996 // (non-visible) declaration, and complain about it. 2997 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2998 = LocallyScopedExternalDecls.find(&II); 2999 if (Pos != LocallyScopedExternalDecls.end()) { 3000 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3001 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3002 return Pos->second; 3003 } 3004 3005 // Extension in C99. Legal in C90, but warn about it. 3006 if (getLangOptions().C99) 3007 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3008 else 3009 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3010 3011 // FIXME: handle stuff like: 3012 // void foo() { extern float X(); } 3013 // void bar() { X(); } <-- implicit decl for X in another scope. 3014 3015 // Set a Declarator for the implicit definition: int foo(); 3016 const char *Dummy; 3017 DeclSpec DS; 3018 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3019 Error = Error; // Silence warning. 3020 assert(!Error && "Error setting up implicit decl!"); 3021 Declarator D(DS, Declarator::BlockContext); 3022 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3023 0, 0, 0, Loc, D), 3024 SourceLocation()); 3025 D.SetIdentifier(&II, Loc); 3026 3027 // Insert this function into translation-unit scope. 3028 3029 DeclContext *PrevDC = CurContext; 3030 CurContext = Context.getTranslationUnitDecl(); 3031 3032 FunctionDecl *FD = 3033 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3034 FD->setImplicit(); 3035 3036 CurContext = PrevDC; 3037 3038 AddKnownFunctionAttributes(FD); 3039 3040 return FD; 3041} 3042 3043/// \brief Adds any function attributes that we know a priori based on 3044/// the declaration of this function. 3045/// 3046/// These attributes can apply both to implicitly-declared builtins 3047/// (like __builtin___printf_chk) or to library-declared functions 3048/// like NSLog or printf. 3049void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3050 if (FD->isInvalidDecl()) 3051 return; 3052 3053 // If this is a built-in function, map its builtin attributes to 3054 // actual attributes. 3055 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3056 // Handle printf-formatting attributes. 3057 unsigned FormatIdx; 3058 bool HasVAListArg; 3059 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3060 if (!FD->getAttr<FormatAttr>()) 3061 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3062 FormatIdx + 2)); 3063 } 3064 3065 // Mark const if we don't care about errno and that is the only 3066 // thing preventing the function from being const. This allows 3067 // IRgen to use LLVM intrinsics for such functions. 3068 if (!getLangOptions().MathErrno && 3069 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3070 if (!FD->getAttr<ConstAttr>()) 3071 FD->addAttr(::new (Context) ConstAttr()); 3072 } 3073 } 3074 3075 IdentifierInfo *Name = FD->getIdentifier(); 3076 if (!Name) 3077 return; 3078 if ((!getLangOptions().CPlusPlus && 3079 FD->getDeclContext()->isTranslationUnit()) || 3080 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3081 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3082 LinkageSpecDecl::lang_c)) { 3083 // Okay: this could be a libc/libm/Objective-C function we know 3084 // about. 3085 } else 3086 return; 3087 3088 unsigned KnownID; 3089 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3090 if (KnownFunctionIDs[KnownID] == Name) 3091 break; 3092 3093 switch (KnownID) { 3094 case id_NSLog: 3095 case id_NSLogv: 3096 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3097 // FIXME: We known better than our headers. 3098 const_cast<FormatAttr *>(Format)->setType("printf"); 3099 } else 3100 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3101 break; 3102 3103 case id_asprintf: 3104 case id_vasprintf: 3105 if (!FD->getAttr<FormatAttr>()) 3106 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3107 break; 3108 3109 default: 3110 // Unknown function or known function without any attributes to 3111 // add. Do nothing. 3112 break; 3113 } 3114} 3115 3116TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3117 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3118 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3119 3120 // Scope manipulation handled by caller. 3121 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3122 D.getIdentifierLoc(), 3123 D.getIdentifier(), 3124 T); 3125 3126 if (TagType *TT = dyn_cast<TagType>(T)) { 3127 TagDecl *TD = TT->getDecl(); 3128 3129 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3130 // keep track of the TypedefDecl. 3131 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3132 TD->setTypedefForAnonDecl(NewTD); 3133 } 3134 3135 if (D.getInvalidType()) 3136 NewTD->setInvalidDecl(); 3137 return NewTD; 3138} 3139 3140/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3141/// former case, Name will be non-null. In the later case, Name will be null. 3142/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3143/// reference/declaration/definition of a tag. 3144Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3145 SourceLocation KWLoc, const CXXScopeSpec &SS, 3146 IdentifierInfo *Name, SourceLocation NameLoc, 3147 AttributeList *Attr, AccessSpecifier AS) { 3148 // If this is not a definition, it must have a name. 3149 assert((Name != 0 || TK == TK_Definition) && 3150 "Nameless record must be a definition!"); 3151 3152 TagDecl::TagKind Kind; 3153 switch (TagSpec) { 3154 default: assert(0 && "Unknown tag type!"); 3155 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3156 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3157 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3158 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3159 } 3160 3161 DeclContext *SearchDC = CurContext; 3162 DeclContext *DC = CurContext; 3163 NamedDecl *PrevDecl = 0; 3164 3165 bool Invalid = false; 3166 3167 if (Name && SS.isNotEmpty()) { 3168 // We have a nested-name tag ('struct foo::bar'). 3169 3170 // Check for invalid 'foo::'. 3171 if (SS.isInvalid()) { 3172 Name = 0; 3173 goto CreateNewDecl; 3174 } 3175 3176 // FIXME: RequireCompleteDeclContext(SS)? 3177 DC = computeDeclContext(SS); 3178 SearchDC = DC; 3179 // Look-up name inside 'foo::'. 3180 PrevDecl = dyn_cast_or_null<TagDecl>( 3181 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3182 3183 // A tag 'foo::bar' must already exist. 3184 if (PrevDecl == 0) { 3185 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3186 Name = 0; 3187 goto CreateNewDecl; 3188 } 3189 } else if (Name) { 3190 // If this is a named struct, check to see if there was a previous forward 3191 // declaration or definition. 3192 // FIXME: We're looking into outer scopes here, even when we 3193 // shouldn't be. Doing so can result in ambiguities that we 3194 // shouldn't be diagnosing. 3195 LookupResult R = LookupName(S, Name, LookupTagName, 3196 /*RedeclarationOnly=*/(TK != TK_Reference)); 3197 if (R.isAmbiguous()) { 3198 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3199 // FIXME: This is not best way to recover from case like: 3200 // 3201 // struct S s; 3202 // 3203 // causes needless "incomplete type" error later. 3204 Name = 0; 3205 PrevDecl = 0; 3206 Invalid = true; 3207 } 3208 else 3209 PrevDecl = R; 3210 3211 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3212 // FIXME: This makes sure that we ignore the contexts associated 3213 // with C structs, unions, and enums when looking for a matching 3214 // tag declaration or definition. See the similar lookup tweak 3215 // in Sema::LookupName; is there a better way to deal with this? 3216 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3217 SearchDC = SearchDC->getParent(); 3218 } 3219 } 3220 3221 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3222 // Maybe we will complain about the shadowed template parameter. 3223 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3224 // Just pretend that we didn't see the previous declaration. 3225 PrevDecl = 0; 3226 } 3227 3228 if (PrevDecl) { 3229 // Check whether the previous declaration is usable. 3230 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3231 3232 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3233 // If this is a use of a previous tag, or if the tag is already declared 3234 // in the same scope (so that the definition/declaration completes or 3235 // rementions the tag), reuse the decl. 3236 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3237 // Make sure that this wasn't declared as an enum and now used as a 3238 // struct or something similar. 3239 if (PrevTagDecl->getTagKind() != Kind) { 3240 bool SafeToContinue 3241 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3242 Kind != TagDecl::TK_enum); 3243 if (SafeToContinue) 3244 Diag(KWLoc, diag::err_use_with_wrong_tag) 3245 << Name 3246 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3247 PrevTagDecl->getKindName()); 3248 else 3249 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3250 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3251 3252 if (SafeToContinue) 3253 Kind = PrevTagDecl->getTagKind(); 3254 else { 3255 // Recover by making this an anonymous redefinition. 3256 Name = 0; 3257 PrevDecl = 0; 3258 Invalid = true; 3259 } 3260 } 3261 3262 if (!Invalid) { 3263 // If this is a use, just return the declaration we found. 3264 3265 // FIXME: In the future, return a variant or some other clue 3266 // for the consumer of this Decl to know it doesn't own it. 3267 // For our current ASTs this shouldn't be a problem, but will 3268 // need to be changed with DeclGroups. 3269 if (TK == TK_Reference) 3270 return DeclPtrTy::make(PrevDecl); 3271 3272 // Diagnose attempts to redefine a tag. 3273 if (TK == TK_Definition) { 3274 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3275 Diag(NameLoc, diag::err_redefinition) << Name; 3276 Diag(Def->getLocation(), diag::note_previous_definition); 3277 // If this is a redefinition, recover by making this 3278 // struct be anonymous, which will make any later 3279 // references get the previous definition. 3280 Name = 0; 3281 PrevDecl = 0; 3282 Invalid = true; 3283 } else { 3284 // If the type is currently being defined, complain 3285 // about a nested redefinition. 3286 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3287 if (Tag->isBeingDefined()) { 3288 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3289 Diag(PrevTagDecl->getLocation(), 3290 diag::note_previous_definition); 3291 Name = 0; 3292 PrevDecl = 0; 3293 Invalid = true; 3294 } 3295 } 3296 3297 // Okay, this is definition of a previously declared or referenced 3298 // tag PrevDecl. We're going to create a new Decl for it. 3299 } 3300 } 3301 // If we get here we have (another) forward declaration or we 3302 // have a definition. Just create a new decl. 3303 } else { 3304 // If we get here, this is a definition of a new tag type in a nested 3305 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3306 // new decl/type. We set PrevDecl to NULL so that the entities 3307 // have distinct types. 3308 PrevDecl = 0; 3309 } 3310 // If we get here, we're going to create a new Decl. If PrevDecl 3311 // is non-NULL, it's a definition of the tag declared by 3312 // PrevDecl. If it's NULL, we have a new definition. 3313 } else { 3314 // PrevDecl is a namespace, template, or anything else 3315 // that lives in the IDNS_Tag identifier namespace. 3316 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3317 // The tag name clashes with a namespace name, issue an error and 3318 // recover by making this tag be anonymous. 3319 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3320 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3321 Name = 0; 3322 PrevDecl = 0; 3323 Invalid = true; 3324 } else { 3325 // The existing declaration isn't relevant to us; we're in a 3326 // new scope, so clear out the previous declaration. 3327 PrevDecl = 0; 3328 } 3329 } 3330 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3331 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3332 // C.scope.pdecl]p5: 3333 // -- for an elaborated-type-specifier of the form 3334 // 3335 // class-key identifier 3336 // 3337 // if the elaborated-type-specifier is used in the 3338 // decl-specifier-seq or parameter-declaration-clause of a 3339 // function defined in namespace scope, the identifier is 3340 // declared as a class-name in the namespace that contains 3341 // the declaration; otherwise, except as a friend 3342 // declaration, the identifier is declared in the smallest 3343 // non-class, non-function-prototype scope that contains the 3344 // declaration. 3345 // 3346 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3347 // C structs and unions. 3348 // 3349 // GNU C also supports this behavior as part of its incomplete 3350 // enum types extension, while GNU C++ does not. 3351 // 3352 // Find the context where we'll be declaring the tag. 3353 // FIXME: We would like to maintain the current DeclContext as the 3354 // lexical context, 3355 while (SearchDC->isRecord()) 3356 SearchDC = SearchDC->getParent(); 3357 3358 // Find the scope where we'll be declaring the tag. 3359 while (S->isClassScope() || 3360 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3361 ((S->getFlags() & Scope::DeclScope) == 0) || 3362 (S->getEntity() && 3363 ((DeclContext *)S->getEntity())->isTransparentContext())) 3364 S = S->getParent(); 3365 } 3366 3367CreateNewDecl: 3368 3369 // If there is an identifier, use the location of the identifier as the 3370 // location of the decl, otherwise use the location of the struct/union 3371 // keyword. 3372 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3373 3374 // Otherwise, create a new declaration. If there is a previous 3375 // declaration of the same entity, the two will be linked via 3376 // PrevDecl. 3377 TagDecl *New; 3378 3379 if (Kind == TagDecl::TK_enum) { 3380 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3381 // enum X { A, B, C } D; D should chain to X. 3382 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3383 cast_or_null<EnumDecl>(PrevDecl)); 3384 // If this is an undefined enum, warn. 3385 if (TK != TK_Definition && !Invalid) { 3386 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3387 : diag::ext_forward_ref_enum; 3388 Diag(Loc, DK); 3389 } 3390 } else { 3391 // struct/union/class 3392 3393 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3394 // struct X { int A; } D; D should chain to X. 3395 if (getLangOptions().CPlusPlus) 3396 // FIXME: Look for a way to use RecordDecl for simple structs. 3397 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3398 cast_or_null<CXXRecordDecl>(PrevDecl)); 3399 else 3400 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3401 cast_or_null<RecordDecl>(PrevDecl)); 3402 } 3403 3404 if (Kind != TagDecl::TK_enum) { 3405 // Handle #pragma pack: if the #pragma pack stack has non-default 3406 // alignment, make up a packed attribute for this decl. These 3407 // attributes are checked when the ASTContext lays out the 3408 // structure. 3409 // 3410 // It is important for implementing the correct semantics that this 3411 // happen here (in act on tag decl). The #pragma pack stack is 3412 // maintained as a result of parser callbacks which can occur at 3413 // many points during the parsing of a struct declaration (because 3414 // the #pragma tokens are effectively skipped over during the 3415 // parsing of the struct). 3416 if (unsigned Alignment = getPragmaPackAlignment()) 3417 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3418 } 3419 3420 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3421 // C++ [dcl.typedef]p3: 3422 // [...] Similarly, in a given scope, a class or enumeration 3423 // shall not be declared with the same name as a typedef-name 3424 // that is declared in that scope and refers to a type other 3425 // than the class or enumeration itself. 3426 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3427 TypedefDecl *PrevTypedef = 0; 3428 if (Lookup.getKind() == LookupResult::Found) 3429 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3430 3431 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3432 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3433 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3434 Diag(Loc, diag::err_tag_definition_of_typedef) 3435 << Context.getTypeDeclType(New) 3436 << PrevTypedef->getUnderlyingType(); 3437 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3438 Invalid = true; 3439 } 3440 } 3441 3442 if (Invalid) 3443 New->setInvalidDecl(); 3444 3445 if (Attr) 3446 ProcessDeclAttributeList(New, Attr); 3447 3448 // If we're declaring or defining a tag in function prototype scope 3449 // in C, note that this type can only be used within the function. 3450 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3451 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3452 3453 // Set the lexical context. If the tag has a C++ scope specifier, the 3454 // lexical context will be different from the semantic context. 3455 New->setLexicalDeclContext(CurContext); 3456 3457 // Set the access specifier. 3458 SetMemberAccessSpecifier(New, PrevDecl, AS); 3459 3460 if (TK == TK_Definition) 3461 New->startDefinition(); 3462 3463 // If this has an identifier, add it to the scope stack. 3464 if (Name) { 3465 S = getNonFieldDeclScope(S); 3466 PushOnScopeChains(New, S); 3467 } else { 3468 CurContext->addDecl(New); 3469 } 3470 3471 return DeclPtrTy::make(New); 3472} 3473 3474void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3475 AdjustDeclIfTemplate(TagD); 3476 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3477 3478 // Enter the tag context. 3479 PushDeclContext(S, Tag); 3480 3481 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3482 FieldCollector->StartClass(); 3483 3484 if (Record->getIdentifier()) { 3485 // C++ [class]p2: 3486 // [...] The class-name is also inserted into the scope of the 3487 // class itself; this is known as the injected-class-name. For 3488 // purposes of access checking, the injected-class-name is treated 3489 // as if it were a public member name. 3490 CXXRecordDecl *InjectedClassName 3491 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3492 CurContext, Record->getLocation(), 3493 Record->getIdentifier(), Record); 3494 InjectedClassName->setImplicit(); 3495 InjectedClassName->setAccess(AS_public); 3496 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3497 InjectedClassName->setDescribedClassTemplate(Template); 3498 PushOnScopeChains(InjectedClassName, S); 3499 assert(InjectedClassName->isInjectedClassName() && 3500 "Broken injected-class-name"); 3501 } 3502 } 3503} 3504 3505void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3506 AdjustDeclIfTemplate(TagD); 3507 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3508 3509 if (isa<CXXRecordDecl>(Tag)) 3510 FieldCollector->FinishClass(); 3511 3512 // Exit this scope of this tag's definition. 3513 PopDeclContext(); 3514 3515 // Notify the consumer that we've defined a tag. 3516 Consumer.HandleTagDeclDefinition(Tag); 3517} 3518 3519bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3520 QualType FieldTy, const Expr *BitWidth) { 3521 // C99 6.7.2.1p4 - verify the field type. 3522 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3523 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3524 // Handle incomplete types with specific error. 3525 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3526 return true; 3527 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3528 << FieldName << FieldTy << BitWidth->getSourceRange(); 3529 } 3530 3531 // If the bit-width is type- or value-dependent, don't try to check 3532 // it now. 3533 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3534 return false; 3535 3536 llvm::APSInt Value; 3537 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3538 return true; 3539 3540 // Zero-width bitfield is ok for anonymous field. 3541 if (Value == 0 && FieldName) 3542 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3543 3544 if (Value.isSigned() && Value.isNegative()) 3545 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3546 << FieldName << Value.toString(10); 3547 3548 if (!FieldTy->isDependentType()) { 3549 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3550 // FIXME: We won't need the 0 size once we check that the field type is valid. 3551 if (TypeSize && Value.getZExtValue() > TypeSize) 3552 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3553 << FieldName << (unsigned)TypeSize; 3554 } 3555 3556 return false; 3557} 3558 3559/// ActOnField - Each field of a struct/union/class is passed into this in order 3560/// to create a FieldDecl object for it. 3561Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3562 SourceLocation DeclStart, 3563 Declarator &D, ExprTy *BitfieldWidth) { 3564 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3565 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3566 AS_public); 3567 return DeclPtrTy::make(Res); 3568} 3569 3570/// HandleField - Analyze a field of a C struct or a C++ data member. 3571/// 3572FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3573 SourceLocation DeclStart, 3574 Declarator &D, Expr *BitWidth, 3575 AccessSpecifier AS) { 3576 IdentifierInfo *II = D.getIdentifier(); 3577 SourceLocation Loc = DeclStart; 3578 if (II) Loc = D.getIdentifierLoc(); 3579 3580 QualType T = GetTypeForDeclarator(D, S); 3581 3582 if (getLangOptions().CPlusPlus) { 3583 CheckExtraCXXDefaultArguments(D); 3584 } 3585 3586 DiagnoseFunctionSpecifiers(D); 3587 3588 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3589 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3590 PrevDecl = 0; 3591 3592 FieldDecl *NewFD 3593 = CheckFieldDecl(II, T, Record, Loc, 3594 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3595 BitWidth, AS, PrevDecl, &D); 3596 if (NewFD->isInvalidDecl() && PrevDecl) { 3597 // Don't introduce NewFD into scope; there's already something 3598 // with the same name in the same scope. 3599 } else if (II) { 3600 PushOnScopeChains(NewFD, S); 3601 } else 3602 Record->addDecl(NewFD); 3603 3604 return NewFD; 3605} 3606 3607/// \brief Build a new FieldDecl and check its well-formedness. 3608/// 3609/// This routine builds a new FieldDecl given the fields name, type, 3610/// record, etc. \p PrevDecl should refer to any previous declaration 3611/// with the same name and in the same scope as the field to be 3612/// created. 3613/// 3614/// \returns a new FieldDecl. 3615/// 3616/// \todo The Declarator argument is a hack. It will be removed once 3617FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3618 RecordDecl *Record, SourceLocation Loc, 3619 bool Mutable, Expr *BitWidth, 3620 AccessSpecifier AS, NamedDecl *PrevDecl, 3621 Declarator *D) { 3622 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3623 bool InvalidDecl = false; 3624 3625 // If we receive a broken type, recover by assuming 'int' and 3626 // marking this declaration as invalid. 3627 if (T.isNull()) { 3628 InvalidDecl = true; 3629 T = Context.IntTy; 3630 } 3631 3632 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3633 // than a variably modified type. 3634 if (T->isVariablyModifiedType()) { 3635 bool SizeIsNegative; 3636 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3637 SizeIsNegative); 3638 if (!FixedTy.isNull()) { 3639 Diag(Loc, diag::warn_illegal_constant_array_size); 3640 T = FixedTy; 3641 } else { 3642 if (SizeIsNegative) 3643 Diag(Loc, diag::err_typecheck_negative_array_size); 3644 else 3645 Diag(Loc, diag::err_typecheck_field_variable_size); 3646 T = Context.IntTy; 3647 InvalidDecl = true; 3648 } 3649 } 3650 3651 // Fields can not have abstract class types 3652 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3653 AbstractFieldType)) 3654 InvalidDecl = true; 3655 3656 // If this is declared as a bit-field, check the bit-field. 3657 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3658 InvalidDecl = true; 3659 DeleteExpr(BitWidth); 3660 BitWidth = 0; 3661 } 3662 3663 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3664 Mutable); 3665 3666 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3667 Diag(Loc, diag::err_duplicate_member) << II; 3668 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3669 NewFD->setInvalidDecl(); 3670 Record->setInvalidDecl(); 3671 } 3672 3673 if (getLangOptions().CPlusPlus && !T->isPODType()) 3674 cast<CXXRecordDecl>(Record)->setPOD(false); 3675 3676 // FIXME: We need to pass in the attributes given an AST 3677 // representation, not a parser representation. 3678 if (D) 3679 ProcessDeclAttributes(NewFD, *D); 3680 3681 if (T.isObjCGCWeak()) 3682 Diag(Loc, diag::warn_attribute_weak_on_field); 3683 3684 if (InvalidDecl) 3685 NewFD->setInvalidDecl(); 3686 3687 NewFD->setAccess(AS); 3688 3689 // C++ [dcl.init.aggr]p1: 3690 // An aggregate is an array or a class (clause 9) with [...] no 3691 // private or protected non-static data members (clause 11). 3692 // A POD must be an aggregate. 3693 if (getLangOptions().CPlusPlus && 3694 (AS == AS_private || AS == AS_protected)) { 3695 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3696 CXXRecord->setAggregate(false); 3697 CXXRecord->setPOD(false); 3698 } 3699 3700 return NewFD; 3701} 3702 3703/// TranslateIvarVisibility - Translate visibility from a token ID to an 3704/// AST enum value. 3705static ObjCIvarDecl::AccessControl 3706TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3707 switch (ivarVisibility) { 3708 default: assert(0 && "Unknown visitibility kind"); 3709 case tok::objc_private: return ObjCIvarDecl::Private; 3710 case tok::objc_public: return ObjCIvarDecl::Public; 3711 case tok::objc_protected: return ObjCIvarDecl::Protected; 3712 case tok::objc_package: return ObjCIvarDecl::Package; 3713 } 3714} 3715 3716/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3717/// in order to create an IvarDecl object for it. 3718Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3719 SourceLocation DeclStart, 3720 Declarator &D, ExprTy *BitfieldWidth, 3721 tok::ObjCKeywordKind Visibility) { 3722 3723 IdentifierInfo *II = D.getIdentifier(); 3724 Expr *BitWidth = (Expr*)BitfieldWidth; 3725 SourceLocation Loc = DeclStart; 3726 if (II) Loc = D.getIdentifierLoc(); 3727 3728 // FIXME: Unnamed fields can be handled in various different ways, for 3729 // example, unnamed unions inject all members into the struct namespace! 3730 3731 QualType T = GetTypeForDeclarator(D, S); 3732 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3733 bool InvalidDecl = false; 3734 3735 if (BitWidth) { 3736 // 6.7.2.1p3, 6.7.2.1p4 3737 if (VerifyBitField(Loc, II, T, BitWidth)) { 3738 InvalidDecl = true; 3739 DeleteExpr(BitWidth); 3740 BitWidth = 0; 3741 } 3742 } else { 3743 // Not a bitfield. 3744 3745 // validate II. 3746 3747 } 3748 3749 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3750 // than a variably modified type. 3751 if (T->isVariablyModifiedType()) { 3752 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3753 InvalidDecl = true; 3754 } 3755 3756 // Get the visibility (access control) for this ivar. 3757 ObjCIvarDecl::AccessControl ac = 3758 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3759 : ObjCIvarDecl::None; 3760 3761 // Construct the decl. 3762 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3763 (Expr *)BitfieldWidth); 3764 3765 if (II) { 3766 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3767 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3768 && !isa<TagDecl>(PrevDecl)) { 3769 Diag(Loc, diag::err_duplicate_member) << II; 3770 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3771 NewID->setInvalidDecl(); 3772 } 3773 } 3774 3775 // Process attributes attached to the ivar. 3776 ProcessDeclAttributes(NewID, D); 3777 3778 if (D.getInvalidType() || InvalidDecl) 3779 NewID->setInvalidDecl(); 3780 3781 if (II) { 3782 // FIXME: When interfaces are DeclContexts, we'll need to add 3783 // these to the interface. 3784 S->AddDecl(DeclPtrTy::make(NewID)); 3785 IdResolver.AddDecl(NewID); 3786 } 3787 3788 return DeclPtrTy::make(NewID); 3789} 3790 3791void Sema::ActOnFields(Scope* S, 3792 SourceLocation RecLoc, DeclPtrTy RecDecl, 3793 DeclPtrTy *Fields, unsigned NumFields, 3794 SourceLocation LBrac, SourceLocation RBrac, 3795 AttributeList *Attr) { 3796 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3797 assert(EnclosingDecl && "missing record or interface decl"); 3798 3799 // If the decl this is being inserted into is invalid, then it may be a 3800 // redeclaration or some other bogus case. Don't try to add fields to it. 3801 if (EnclosingDecl->isInvalidDecl()) { 3802 // FIXME: Deallocate fields? 3803 return; 3804 } 3805 3806 3807 // Verify that all the fields are okay. 3808 unsigned NumNamedMembers = 0; 3809 llvm::SmallVector<FieldDecl*, 32> RecFields; 3810 3811 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3812 for (unsigned i = 0; i != NumFields; ++i) { 3813 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3814 3815 // Get the type for the field. 3816 Type *FDTy = FD->getType().getTypePtr(); 3817 3818 if (!FD->isAnonymousStructOrUnion()) { 3819 // Remember all fields written by the user. 3820 RecFields.push_back(FD); 3821 } 3822 3823 // If the field is already invalid for some reason, don't emit more 3824 // diagnostics about it. 3825 if (FD->isInvalidDecl()) 3826 continue; 3827 3828 // C99 6.7.2.1p2: 3829 // A structure or union shall not contain a member with 3830 // incomplete or function type (hence, a structure shall not 3831 // contain an instance of itself, but may contain a pointer to 3832 // an instance of itself), except that the last member of a 3833 // structure with more than one named member may have incomplete 3834 // array type; such a structure (and any union containing, 3835 // possibly recursively, a member that is such a structure) 3836 // shall not be a member of a structure or an element of an 3837 // array. 3838 if (FDTy->isFunctionType()) { 3839 // Field declared as a function. 3840 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3841 << FD->getDeclName(); 3842 FD->setInvalidDecl(); 3843 EnclosingDecl->setInvalidDecl(); 3844 continue; 3845 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3846 Record && Record->isStruct()) { 3847 // Flexible array member. 3848 if (NumNamedMembers < 1) { 3849 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3850 << FD->getDeclName(); 3851 FD->setInvalidDecl(); 3852 EnclosingDecl->setInvalidDecl(); 3853 continue; 3854 } 3855 // Okay, we have a legal flexible array member at the end of the struct. 3856 if (Record) 3857 Record->setHasFlexibleArrayMember(true); 3858 } else if (!FDTy->isDependentType() && 3859 RequireCompleteType(FD->getLocation(), FD->getType(), 3860 diag::err_field_incomplete)) { 3861 // Incomplete type 3862 FD->setInvalidDecl(); 3863 EnclosingDecl->setInvalidDecl(); 3864 continue; 3865 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3866 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3867 // If this is a member of a union, then entire union becomes "flexible". 3868 if (Record && Record->isUnion()) { 3869 Record->setHasFlexibleArrayMember(true); 3870 } else { 3871 // If this is a struct/class and this is not the last element, reject 3872 // it. Note that GCC supports variable sized arrays in the middle of 3873 // structures. 3874 if (i != NumFields-1) 3875 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3876 << FD->getDeclName(); 3877 else { 3878 // We support flexible arrays at the end of structs in 3879 // other structs as an extension. 3880 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3881 << FD->getDeclName(); 3882 if (Record) 3883 Record->setHasFlexibleArrayMember(true); 3884 } 3885 } 3886 } 3887 } else if (FDTy->isObjCInterfaceType()) { 3888 /// A field cannot be an Objective-c object 3889 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3890 FD->setInvalidDecl(); 3891 EnclosingDecl->setInvalidDecl(); 3892 continue; 3893 } 3894 // Keep track of the number of named members. 3895 if (FD->getIdentifier()) 3896 ++NumNamedMembers; 3897 } 3898 3899 // Okay, we successfully defined 'Record'. 3900 if (Record) { 3901 Record->completeDefinition(Context); 3902 } else { 3903 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3904 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3905 ID->setIVarList(ClsFields, RecFields.size(), Context); 3906 ID->setLocEnd(RBrac); 3907 3908 // Must enforce the rule that ivars in the base classes may not be 3909 // duplicates. 3910 if (ID->getSuperClass()) { 3911 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3912 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3913 ObjCIvarDecl* Ivar = (*IVI); 3914 IdentifierInfo *II = Ivar->getIdentifier(); 3915 ObjCIvarDecl* prevIvar = 3916 ID->getSuperClass()->lookupInstanceVariable(II); 3917 if (prevIvar) { 3918 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3919 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3920 } 3921 } 3922 } 3923 } else if (ObjCImplementationDecl *IMPDecl = 3924 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3925 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3926 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3927 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3928 } 3929 } 3930 3931 if (Attr) 3932 ProcessDeclAttributeList(Record, Attr); 3933} 3934 3935EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 3936 EnumConstantDecl *LastEnumConst, 3937 SourceLocation IdLoc, 3938 IdentifierInfo *Id, 3939 ExprArg val) { 3940 Expr *Val = (Expr *)val.get(); 3941 3942 llvm::APSInt EnumVal(32); 3943 QualType EltTy; 3944 if (Val && !Val->isTypeDependent()) { 3945 // Make sure to promote the operand type to int. 3946 UsualUnaryConversions(Val); 3947 if (Val != val.get()) { 3948 val.release(); 3949 val = Val; 3950 } 3951 3952 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3953 SourceLocation ExpLoc; 3954 if (!Val->isValueDependent() && 3955 VerifyIntegerConstantExpression(Val, &EnumVal)) { 3956 Val = 0; 3957 } else { 3958 EltTy = Val->getType(); 3959 } 3960 } 3961 3962 if (!Val) { 3963 if (LastEnumConst) { 3964 // Assign the last value + 1. 3965 EnumVal = LastEnumConst->getInitVal(); 3966 ++EnumVal; 3967 3968 // Check for overflow on increment. 3969 if (EnumVal < LastEnumConst->getInitVal()) 3970 Diag(IdLoc, diag::warn_enum_value_overflow); 3971 3972 EltTy = LastEnumConst->getType(); 3973 } else { 3974 // First value, set to zero. 3975 EltTy = Context.IntTy; 3976 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3977 } 3978 } 3979 3980 val.release(); 3981 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 3982 Val, EnumVal); 3983} 3984 3985 3986Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 3987 DeclPtrTy lastEnumConst, 3988 SourceLocation IdLoc, 3989 IdentifierInfo *Id, 3990 SourceLocation EqualLoc, ExprTy *val) { 3991 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 3992 EnumConstantDecl *LastEnumConst = 3993 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 3994 Expr *Val = static_cast<Expr*>(val); 3995 3996 // The scope passed in may not be a decl scope. Zip up the scope tree until 3997 // we find one that is. 3998 S = getNonFieldDeclScope(S); 3999 4000 // Verify that there isn't already something declared with this name in this 4001 // scope. 4002 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4003 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4004 // Maybe we will complain about the shadowed template parameter. 4005 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4006 // Just pretend that we didn't see the previous declaration. 4007 PrevDecl = 0; 4008 } 4009 4010 if (PrevDecl) { 4011 // When in C++, we may get a TagDecl with the same name; in this case the 4012 // enum constant will 'hide' the tag. 4013 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4014 "Received TagDecl when not in C++!"); 4015 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4016 if (isa<EnumConstantDecl>(PrevDecl)) 4017 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4018 else 4019 Diag(IdLoc, diag::err_redefinition) << Id; 4020 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4021 if (Val) Val->Destroy(Context); 4022 return DeclPtrTy(); 4023 } 4024 } 4025 4026 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4027 IdLoc, Id, Owned(Val)); 4028 4029 // Register this decl in the current scope stack. 4030 if (New) 4031 PushOnScopeChains(New, S); 4032 4033 return DeclPtrTy::make(New); 4034} 4035 4036// FIXME: For consistency with ActOnFields(), we should have the parser 4037// pass in the source location for the left/right braces. 4038void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4039 DeclPtrTy *Elements, unsigned NumElements) { 4040 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4041 QualType EnumType = Context.getTypeDeclType(Enum); 4042 4043 // TODO: If the result value doesn't fit in an int, it must be a long or long 4044 // long value. ISO C does not support this, but GCC does as an extension, 4045 // emit a warning. 4046 unsigned IntWidth = Context.Target.getIntWidth(); 4047 4048 // Verify that all the values are okay, compute the size of the values, and 4049 // reverse the list. 4050 unsigned NumNegativeBits = 0; 4051 unsigned NumPositiveBits = 0; 4052 4053 // Keep track of whether all elements have type int. 4054 bool AllElementsInt = true; 4055 4056 for (unsigned i = 0; i != NumElements; ++i) { 4057 EnumConstantDecl *ECD = 4058 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4059 if (!ECD) continue; // Already issued a diagnostic. 4060 4061 // If the enum value doesn't fit in an int, emit an extension warning. 4062 const llvm::APSInt &InitVal = ECD->getInitVal(); 4063 assert(InitVal.getBitWidth() >= IntWidth && 4064 "Should have promoted value to int"); 4065 if (InitVal.getBitWidth() > IntWidth) { 4066 llvm::APSInt V(InitVal); 4067 V.trunc(IntWidth); 4068 V.extend(InitVal.getBitWidth()); 4069 if (V != InitVal) 4070 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4071 << InitVal.toString(10); 4072 } 4073 4074 // Keep track of the size of positive and negative values. 4075 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4076 NumPositiveBits = std::max(NumPositiveBits, 4077 (unsigned)InitVal.getActiveBits()); 4078 else 4079 NumNegativeBits = std::max(NumNegativeBits, 4080 (unsigned)InitVal.getMinSignedBits()); 4081 4082 // Keep track of whether every enum element has type int (very commmon). 4083 if (AllElementsInt) 4084 AllElementsInt = ECD->getType() == Context.IntTy; 4085 } 4086 4087 // Figure out the type that should be used for this enum. 4088 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4089 QualType BestType; 4090 unsigned BestWidth; 4091 4092 if (NumNegativeBits) { 4093 // If there is a negative value, figure out the smallest integer type (of 4094 // int/long/longlong) that fits. 4095 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4096 BestType = Context.IntTy; 4097 BestWidth = IntWidth; 4098 } else { 4099 BestWidth = Context.Target.getLongWidth(); 4100 4101 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4102 BestType = Context.LongTy; 4103 else { 4104 BestWidth = Context.Target.getLongLongWidth(); 4105 4106 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4107 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4108 BestType = Context.LongLongTy; 4109 } 4110 } 4111 } else { 4112 // If there is no negative value, figure out which of uint, ulong, ulonglong 4113 // fits. 4114 if (NumPositiveBits <= IntWidth) { 4115 BestType = Context.UnsignedIntTy; 4116 BestWidth = IntWidth; 4117 } else if (NumPositiveBits <= 4118 (BestWidth = Context.Target.getLongWidth())) { 4119 BestType = Context.UnsignedLongTy; 4120 } else { 4121 BestWidth = Context.Target.getLongLongWidth(); 4122 assert(NumPositiveBits <= BestWidth && 4123 "How could an initializer get larger than ULL?"); 4124 BestType = Context.UnsignedLongLongTy; 4125 } 4126 } 4127 4128 // Loop over all of the enumerator constants, changing their types to match 4129 // the type of the enum if needed. 4130 for (unsigned i = 0; i != NumElements; ++i) { 4131 EnumConstantDecl *ECD = 4132 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4133 if (!ECD) continue; // Already issued a diagnostic. 4134 4135 // Standard C says the enumerators have int type, but we allow, as an 4136 // extension, the enumerators to be larger than int size. If each 4137 // enumerator value fits in an int, type it as an int, otherwise type it the 4138 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4139 // that X has type 'int', not 'unsigned'. 4140 if (ECD->getType() == Context.IntTy) { 4141 // Make sure the init value is signed. 4142 llvm::APSInt IV = ECD->getInitVal(); 4143 IV.setIsSigned(true); 4144 ECD->setInitVal(IV); 4145 4146 if (getLangOptions().CPlusPlus) 4147 // C++ [dcl.enum]p4: Following the closing brace of an 4148 // enum-specifier, each enumerator has the type of its 4149 // enumeration. 4150 ECD->setType(EnumType); 4151 continue; // Already int type. 4152 } 4153 4154 // Determine whether the value fits into an int. 4155 llvm::APSInt InitVal = ECD->getInitVal(); 4156 bool FitsInInt; 4157 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4158 FitsInInt = InitVal.getActiveBits() < IntWidth; 4159 else 4160 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4161 4162 // If it fits into an integer type, force it. Otherwise force it to match 4163 // the enum decl type. 4164 QualType NewTy; 4165 unsigned NewWidth; 4166 bool NewSign; 4167 if (FitsInInt) { 4168 NewTy = Context.IntTy; 4169 NewWidth = IntWidth; 4170 NewSign = true; 4171 } else if (ECD->getType() == BestType) { 4172 // Already the right type! 4173 if (getLangOptions().CPlusPlus) 4174 // C++ [dcl.enum]p4: Following the closing brace of an 4175 // enum-specifier, each enumerator has the type of its 4176 // enumeration. 4177 ECD->setType(EnumType); 4178 continue; 4179 } else { 4180 NewTy = BestType; 4181 NewWidth = BestWidth; 4182 NewSign = BestType->isSignedIntegerType(); 4183 } 4184 4185 // Adjust the APSInt value. 4186 InitVal.extOrTrunc(NewWidth); 4187 InitVal.setIsSigned(NewSign); 4188 ECD->setInitVal(InitVal); 4189 4190 // Adjust the Expr initializer and type. 4191 if (ECD->getInitExpr()) 4192 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4193 /*isLvalue=*/false)); 4194 if (getLangOptions().CPlusPlus) 4195 // C++ [dcl.enum]p4: Following the closing brace of an 4196 // enum-specifier, each enumerator has the type of its 4197 // enumeration. 4198 ECD->setType(EnumType); 4199 else 4200 ECD->setType(NewTy); 4201 } 4202 4203 Enum->completeDefinition(Context, BestType); 4204} 4205 4206Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4207 ExprArg expr) { 4208 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4209 4210 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4211 Loc, AsmString)); 4212} 4213 4214