SemaDecl.cpp revision 5186872629d6c9a48433bafe62dc06975bbbf7af
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(Context, 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 // FIXME: Error on auto/register at file scope 938 // FIXME: Error on inline/virtual/explicit 939 // FIXME: Error on invalid restrict 940 // FIXME: Warn on useless const/volatile 941 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 942 // FIXME: Warn on useless attributes 943 944 TagDecl *Tag = 0; 945 if (DS.getTypeSpecType() == DeclSpec::TST_class || 946 DS.getTypeSpecType() == DeclSpec::TST_struct || 947 DS.getTypeSpecType() == DeclSpec::TST_union || 948 DS.getTypeSpecType() == DeclSpec::TST_enum) 949 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 950 951 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 952 if (!Record->getDeclName() && Record->isDefinition() && 953 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 954 if (getLangOptions().CPlusPlus || 955 Record->getDeclContext()->isRecord()) 956 return BuildAnonymousStructOrUnion(S, DS, Record); 957 958 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 959 << DS.getSourceRange(); 960 } 961 962 // Microsoft allows unnamed struct/union fields. Don't complain 963 // about them. 964 // FIXME: Should we support Microsoft's extensions in this area? 965 if (Record->getDeclName() && getLangOptions().Microsoft) 966 return DeclPtrTy::make(Tag); 967 } 968 969 if (!DS.isMissingDeclaratorOk() && 970 DS.getTypeSpecType() != DeclSpec::TST_error) { 971 // Warn about typedefs of enums without names, since this is an 972 // extension in both Microsoft an GNU. 973 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 974 Tag && isa<EnumDecl>(Tag)) { 975 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 976 << DS.getSourceRange(); 977 return DeclPtrTy::make(Tag); 978 } 979 980 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 981 << DS.getSourceRange(); 982 return DeclPtrTy(); 983 } 984 985 return DeclPtrTy::make(Tag); 986} 987 988/// InjectAnonymousStructOrUnionMembers - Inject the members of the 989/// anonymous struct or union AnonRecord into the owning context Owner 990/// and scope S. This routine will be invoked just after we realize 991/// that an unnamed union or struct is actually an anonymous union or 992/// struct, e.g., 993/// 994/// @code 995/// union { 996/// int i; 997/// float f; 998/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 999/// // f into the surrounding scope.x 1000/// @endcode 1001/// 1002/// This routine is recursive, injecting the names of nested anonymous 1003/// structs/unions into the owning context and scope as well. 1004bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1005 RecordDecl *AnonRecord) { 1006 bool Invalid = false; 1007 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1008 FEnd = AnonRecord->field_end(Context); 1009 F != FEnd; ++F) { 1010 if ((*F)->getDeclName()) { 1011 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1012 LookupOrdinaryName, true); 1013 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1014 // C++ [class.union]p2: 1015 // The names of the members of an anonymous union shall be 1016 // distinct from the names of any other entity in the 1017 // scope in which the anonymous union is declared. 1018 unsigned diagKind 1019 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1020 : diag::err_anonymous_struct_member_redecl; 1021 Diag((*F)->getLocation(), diagKind) 1022 << (*F)->getDeclName(); 1023 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1024 Invalid = true; 1025 } else { 1026 // C++ [class.union]p2: 1027 // For the purpose of name lookup, after the anonymous union 1028 // definition, the members of the anonymous union are 1029 // considered to have been defined in the scope in which the 1030 // anonymous union is declared. 1031 Owner->makeDeclVisibleInContext(Context, *F); 1032 S->AddDecl(DeclPtrTy::make(*F)); 1033 IdResolver.AddDecl(*F); 1034 } 1035 } else if (const RecordType *InnerRecordType 1036 = (*F)->getType()->getAsRecordType()) { 1037 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1038 if (InnerRecord->isAnonymousStructOrUnion()) 1039 Invalid = Invalid || 1040 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1041 } 1042 } 1043 1044 return Invalid; 1045} 1046 1047/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1048/// anonymous structure or union. Anonymous unions are a C++ feature 1049/// (C++ [class.union]) and a GNU C extension; anonymous structures 1050/// are a GNU C and GNU C++ extension. 1051Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1052 RecordDecl *Record) { 1053 DeclContext *Owner = Record->getDeclContext(); 1054 1055 // Diagnose whether this anonymous struct/union is an extension. 1056 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1057 Diag(Record->getLocation(), diag::ext_anonymous_union); 1058 else if (!Record->isUnion()) 1059 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1060 1061 // C and C++ require different kinds of checks for anonymous 1062 // structs/unions. 1063 bool Invalid = false; 1064 if (getLangOptions().CPlusPlus) { 1065 const char* PrevSpec = 0; 1066 // C++ [class.union]p3: 1067 // Anonymous unions declared in a named namespace or in the 1068 // global namespace shall be declared static. 1069 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1070 (isa<TranslationUnitDecl>(Owner) || 1071 (isa<NamespaceDecl>(Owner) && 1072 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1073 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1074 Invalid = true; 1075 1076 // Recover by adding 'static'. 1077 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1078 } 1079 // C++ [class.union]p3: 1080 // A storage class is not allowed in a declaration of an 1081 // anonymous union in a class scope. 1082 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1083 isa<RecordDecl>(Owner)) { 1084 Diag(DS.getStorageClassSpecLoc(), 1085 diag::err_anonymous_union_with_storage_spec); 1086 Invalid = true; 1087 1088 // Recover by removing the storage specifier. 1089 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1090 PrevSpec); 1091 } 1092 1093 // C++ [class.union]p2: 1094 // The member-specification of an anonymous union shall only 1095 // define non-static data members. [Note: nested types and 1096 // functions cannot be declared within an anonymous union. ] 1097 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1098 MemEnd = Record->decls_end(Context); 1099 Mem != MemEnd; ++Mem) { 1100 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1101 // C++ [class.union]p3: 1102 // An anonymous union shall not have private or protected 1103 // members (clause 11). 1104 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1105 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1106 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1107 Invalid = true; 1108 } 1109 } else if ((*Mem)->isImplicit()) { 1110 // Any implicit members are fine. 1111 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1112 // This is a type that showed up in an 1113 // elaborated-type-specifier inside the anonymous struct or 1114 // union, but which actually declares a type outside of the 1115 // anonymous struct or union. It's okay. 1116 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1117 if (!MemRecord->isAnonymousStructOrUnion() && 1118 MemRecord->getDeclName()) { 1119 // This is a nested type declaration. 1120 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1121 << (int)Record->isUnion(); 1122 Invalid = true; 1123 } 1124 } else { 1125 // We have something that isn't a non-static data 1126 // member. Complain about it. 1127 unsigned DK = diag::err_anonymous_record_bad_member; 1128 if (isa<TypeDecl>(*Mem)) 1129 DK = diag::err_anonymous_record_with_type; 1130 else if (isa<FunctionDecl>(*Mem)) 1131 DK = diag::err_anonymous_record_with_function; 1132 else if (isa<VarDecl>(*Mem)) 1133 DK = diag::err_anonymous_record_with_static; 1134 Diag((*Mem)->getLocation(), DK) 1135 << (int)Record->isUnion(); 1136 Invalid = true; 1137 } 1138 } 1139 } 1140 1141 if (!Record->isUnion() && !Owner->isRecord()) { 1142 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1143 << (int)getLangOptions().CPlusPlus; 1144 Invalid = true; 1145 } 1146 1147 // Create a declaration for this anonymous struct/union. 1148 NamedDecl *Anon = 0; 1149 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1150 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1151 /*IdentifierInfo=*/0, 1152 Context.getTypeDeclType(Record), 1153 /*BitWidth=*/0, /*Mutable=*/false); 1154 Anon->setAccess(AS_public); 1155 if (getLangOptions().CPlusPlus) 1156 FieldCollector->Add(cast<FieldDecl>(Anon)); 1157 } else { 1158 VarDecl::StorageClass SC; 1159 switch (DS.getStorageClassSpec()) { 1160 default: assert(0 && "Unknown storage class!"); 1161 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1162 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1163 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1164 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1165 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1166 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1167 case DeclSpec::SCS_mutable: 1168 // mutable can only appear on non-static class members, so it's always 1169 // an error here 1170 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1171 Invalid = true; 1172 SC = VarDecl::None; 1173 break; 1174 } 1175 1176 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1177 /*IdentifierInfo=*/0, 1178 Context.getTypeDeclType(Record), 1179 SC, DS.getSourceRange().getBegin()); 1180 } 1181 Anon->setImplicit(); 1182 1183 // Add the anonymous struct/union object to the current 1184 // context. We'll be referencing this object when we refer to one of 1185 // its members. 1186 Owner->addDecl(Context, Anon); 1187 1188 // Inject the members of the anonymous struct/union into the owning 1189 // context and into the identifier resolver chain for name lookup 1190 // purposes. 1191 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1192 Invalid = true; 1193 1194 // Mark this as an anonymous struct/union type. Note that we do not 1195 // do this until after we have already checked and injected the 1196 // members of this anonymous struct/union type, because otherwise 1197 // the members could be injected twice: once by DeclContext when it 1198 // builds its lookup table, and once by 1199 // InjectAnonymousStructOrUnionMembers. 1200 Record->setAnonymousStructOrUnion(true); 1201 1202 if (Invalid) 1203 Anon->setInvalidDecl(); 1204 1205 return DeclPtrTy::make(Anon); 1206} 1207 1208 1209/// GetNameForDeclarator - Determine the full declaration name for the 1210/// given Declarator. 1211DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1212 switch (D.getKind()) { 1213 case Declarator::DK_Abstract: 1214 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1215 return DeclarationName(); 1216 1217 case Declarator::DK_Normal: 1218 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1219 return DeclarationName(D.getIdentifier()); 1220 1221 case Declarator::DK_Constructor: { 1222 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1223 Ty = Context.getCanonicalType(Ty); 1224 return Context.DeclarationNames.getCXXConstructorName(Ty); 1225 } 1226 1227 case Declarator::DK_Destructor: { 1228 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1229 Ty = Context.getCanonicalType(Ty); 1230 return Context.DeclarationNames.getCXXDestructorName(Ty); 1231 } 1232 1233 case Declarator::DK_Conversion: { 1234 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1235 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1236 Ty = Context.getCanonicalType(Ty); 1237 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1238 } 1239 1240 case Declarator::DK_Operator: 1241 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1242 return Context.DeclarationNames.getCXXOperatorName( 1243 D.getOverloadedOperator()); 1244 } 1245 1246 assert(false && "Unknown name kind"); 1247 return DeclarationName(); 1248} 1249 1250/// isNearlyMatchingFunction - Determine whether the C++ functions 1251/// Declaration and Definition are "nearly" matching. This heuristic 1252/// is used to improve diagnostics in the case where an out-of-line 1253/// function definition doesn't match any declaration within 1254/// the class or namespace. 1255static bool isNearlyMatchingFunction(ASTContext &Context, 1256 FunctionDecl *Declaration, 1257 FunctionDecl *Definition) { 1258 if (Declaration->param_size() != Definition->param_size()) 1259 return false; 1260 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1261 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1262 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1263 1264 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1265 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1266 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1267 return false; 1268 } 1269 1270 return true; 1271} 1272 1273Sema::DeclPtrTy 1274Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1275 DeclarationName Name = GetNameForDeclarator(D); 1276 1277 // All of these full declarators require an identifier. If it doesn't have 1278 // one, the ParsedFreeStandingDeclSpec action should be used. 1279 if (!Name) { 1280 if (!D.getInvalidType()) // Reject this if we think it is valid. 1281 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1282 diag::err_declarator_need_ident) 1283 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1284 return DeclPtrTy(); 1285 } 1286 1287 // The scope passed in may not be a decl scope. Zip up the scope tree until 1288 // we find one that is. 1289 while ((S->getFlags() & Scope::DeclScope) == 0 || 1290 (S->getFlags() & Scope::TemplateParamScope) != 0) 1291 S = S->getParent(); 1292 1293 DeclContext *DC; 1294 NamedDecl *PrevDecl; 1295 NamedDecl *New; 1296 bool InvalidDecl = false; 1297 1298 QualType R = GetTypeForDeclarator(D, S); 1299 if (R.isNull()) { 1300 InvalidDecl = true; 1301 R = Context.IntTy; 1302 } 1303 1304 // See if this is a redefinition of a variable in the same scope. 1305 if (D.getCXXScopeSpec().isInvalid()) { 1306 DC = CurContext; 1307 PrevDecl = 0; 1308 InvalidDecl = true; 1309 } else if (!D.getCXXScopeSpec().isSet()) { 1310 LookupNameKind NameKind = LookupOrdinaryName; 1311 1312 // If the declaration we're planning to build will be a function 1313 // or object with linkage, then look for another declaration with 1314 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1315 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1316 /* Do nothing*/; 1317 else if (R->isFunctionType()) { 1318 if (CurContext->isFunctionOrMethod()) 1319 NameKind = LookupRedeclarationWithLinkage; 1320 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1321 NameKind = LookupRedeclarationWithLinkage; 1322 1323 DC = CurContext; 1324 PrevDecl = LookupName(S, Name, NameKind, true, 1325 D.getDeclSpec().getStorageClassSpec() != 1326 DeclSpec::SCS_static, 1327 D.getIdentifierLoc()); 1328 } else { // Something like "int foo::x;" 1329 DC = computeDeclContext(D.getCXXScopeSpec()); 1330 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1331 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1332 1333 // C++ 7.3.1.2p2: 1334 // Members (including explicit specializations of templates) of a named 1335 // namespace can also be defined outside that namespace by explicit 1336 // qualification of the name being defined, provided that the entity being 1337 // defined was already declared in the namespace and the definition appears 1338 // after the point of declaration in a namespace that encloses the 1339 // declarations namespace. 1340 // 1341 // Note that we only check the context at this point. We don't yet 1342 // have enough information to make sure that PrevDecl is actually 1343 // the declaration we want to match. For example, given: 1344 // 1345 // class X { 1346 // void f(); 1347 // void f(float); 1348 // }; 1349 // 1350 // void X::f(int) { } // ill-formed 1351 // 1352 // In this case, PrevDecl will point to the overload set 1353 // containing the two f's declared in X, but neither of them 1354 // matches. 1355 1356 // First check whether we named the global scope. 1357 if (isa<TranslationUnitDecl>(DC)) { 1358 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1359 << Name << D.getCXXScopeSpec().getRange(); 1360 } else if (!CurContext->Encloses(DC)) { 1361 // The qualifying scope doesn't enclose the original declaration. 1362 // Emit diagnostic based on current scope. 1363 SourceLocation L = D.getIdentifierLoc(); 1364 SourceRange R = D.getCXXScopeSpec().getRange(); 1365 if (isa<FunctionDecl>(CurContext)) 1366 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1367 else 1368 Diag(L, diag::err_invalid_declarator_scope) 1369 << Name << cast<NamedDecl>(DC) << R; 1370 InvalidDecl = true; 1371 } 1372 } 1373 1374 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1375 // Maybe we will complain about the shadowed template parameter. 1376 InvalidDecl = InvalidDecl 1377 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1378 // Just pretend that we didn't see the previous declaration. 1379 PrevDecl = 0; 1380 } 1381 1382 // In C++, the previous declaration we find might be a tag type 1383 // (class or enum). In this case, the new declaration will hide the 1384 // tag type. Note that this does does not apply if we're declaring a 1385 // typedef (C++ [dcl.typedef]p4). 1386 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1387 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1388 PrevDecl = 0; 1389 1390 bool Redeclaration = false; 1391 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1392 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, 1393 InvalidDecl, Redeclaration); 1394 } else if (R->isFunctionType()) { 1395 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1396 IsFunctionDefinition, InvalidDecl, 1397 Redeclaration); 1398 } else { 1399 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, 1400 InvalidDecl, Redeclaration); 1401 } 1402 1403 if (New == 0) 1404 return DeclPtrTy(); 1405 1406 // If this has an identifier and is not an invalid redeclaration, 1407 // add it to the scope stack. 1408 if (Name && !(Redeclaration && InvalidDecl)) 1409 PushOnScopeChains(New, S); 1410 // If any semantic error occurred, mark the decl as invalid. 1411 if (D.getInvalidType() || InvalidDecl) 1412 New->setInvalidDecl(); 1413 1414 return DeclPtrTy::make(New); 1415} 1416 1417/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1418/// types into constant array types in certain situations which would otherwise 1419/// be errors (for GCC compatibility). 1420static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1421 ASTContext &Context, 1422 bool &SizeIsNegative) { 1423 // This method tries to turn a variable array into a constant 1424 // array even when the size isn't an ICE. This is necessary 1425 // for compatibility with code that depends on gcc's buggy 1426 // constant expression folding, like struct {char x[(int)(char*)2];} 1427 SizeIsNegative = false; 1428 1429 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1430 QualType Pointee = PTy->getPointeeType(); 1431 QualType FixedType = 1432 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1433 if (FixedType.isNull()) return FixedType; 1434 FixedType = Context.getPointerType(FixedType); 1435 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1436 return FixedType; 1437 } 1438 1439 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1440 if (!VLATy) 1441 return QualType(); 1442 // FIXME: We should probably handle this case 1443 if (VLATy->getElementType()->isVariablyModifiedType()) 1444 return QualType(); 1445 1446 Expr::EvalResult EvalResult; 1447 if (!VLATy->getSizeExpr() || 1448 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1449 !EvalResult.Val.isInt()) 1450 return QualType(); 1451 1452 llvm::APSInt &Res = EvalResult.Val.getInt(); 1453 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1454 return Context.getConstantArrayType(VLATy->getElementType(), 1455 Res, ArrayType::Normal, 0); 1456 1457 SizeIsNegative = true; 1458 return QualType(); 1459} 1460 1461/// \brief Register the given locally-scoped external C declaration so 1462/// that it can be found later for redeclarations 1463void 1464Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1465 Scope *S) { 1466 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1467 "Decl is not a locally-scoped decl!"); 1468 // Note that we have a locally-scoped external with this name. 1469 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1470 1471 if (!PrevDecl) 1472 return; 1473 1474 // If there was a previous declaration of this variable, it may be 1475 // in our identifier chain. Update the identifier chain with the new 1476 // declaration. 1477 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1478 // The previous declaration was found on the identifer resolver 1479 // chain, so remove it from its scope. 1480 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1481 S = S->getParent(); 1482 1483 if (S) 1484 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1485 } 1486} 1487 1488/// \brief Diagnose function specifiers on a declaration of an identifier that 1489/// does not identify a function. 1490void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1491 // FIXME: We should probably indicate the identifier in question to avoid 1492 // confusion for constructs like "inline int a(), b;" 1493 if (D.getDeclSpec().isInlineSpecified()) 1494 Diag(D.getDeclSpec().getInlineSpecLoc(), 1495 diag::err_inline_non_function); 1496 1497 if (D.getDeclSpec().isVirtualSpecified()) 1498 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1499 diag::err_virtual_non_function); 1500 1501 if (D.getDeclSpec().isExplicitSpecified()) 1502 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1503 diag::err_explicit_non_function); 1504} 1505 1506NamedDecl* 1507Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1508 QualType R, Decl* PrevDecl, bool& InvalidDecl, 1509 bool &Redeclaration) { 1510 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1511 if (D.getCXXScopeSpec().isSet()) { 1512 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1513 << D.getCXXScopeSpec().getRange(); 1514 InvalidDecl = true; 1515 // Pretend we didn't see the scope specifier. 1516 DC = 0; 1517 } 1518 1519 if (getLangOptions().CPlusPlus) { 1520 // Check that there are no default arguments (C++ only). 1521 CheckExtraCXXDefaultArguments(D); 1522 } 1523 1524 DiagnoseFunctionSpecifiers(D); 1525 1526 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1527 if (!NewTD) return 0; 1528 1529 // Handle attributes prior to checking for duplicates in MergeVarDecl 1530 ProcessDeclAttributes(NewTD, D); 1531 // Merge the decl with the existing one if appropriate. If the decl is 1532 // in an outer scope, it isn't the same thing. 1533 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1534 Redeclaration = true; 1535 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1536 InvalidDecl = true; 1537 } 1538 1539 if (S->getFnParent() == 0) { 1540 QualType T = NewTD->getUnderlyingType(); 1541 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1542 // then it shall have block scope. 1543 if (T->isVariablyModifiedType()) { 1544 bool SizeIsNegative; 1545 QualType FixedTy = 1546 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1547 if (!FixedTy.isNull()) { 1548 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1549 NewTD->setUnderlyingType(FixedTy); 1550 } else { 1551 if (SizeIsNegative) 1552 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1553 else if (T->isVariableArrayType()) 1554 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1555 else 1556 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1557 InvalidDecl = true; 1558 } 1559 } 1560 } 1561 return NewTD; 1562} 1563 1564/// \brief Determines whether the given declaration is an out-of-scope 1565/// previous declaration. 1566/// 1567/// This routine should be invoked when name lookup has found a 1568/// previous declaration (PrevDecl) that is not in the scope where a 1569/// new declaration by the same name is being introduced. If the new 1570/// declaration occurs in a local scope, previous declarations with 1571/// linkage may still be considered previous declarations (C99 1572/// 6.2.2p4-5, C++ [basic.link]p6). 1573/// 1574/// \param PrevDecl the previous declaration found by name 1575/// lookup 1576/// 1577/// \param DC the context in which the new declaration is being 1578/// declared. 1579/// 1580/// \returns true if PrevDecl is an out-of-scope previous declaration 1581/// for a new delcaration with the same name. 1582static bool 1583isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1584 ASTContext &Context) { 1585 if (!PrevDecl) 1586 return 0; 1587 1588 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1589 // case we need to check each of the overloaded functions. 1590 if (!PrevDecl->hasLinkage()) 1591 return false; 1592 1593 if (Context.getLangOptions().CPlusPlus) { 1594 // C++ [basic.link]p6: 1595 // If there is a visible declaration of an entity with linkage 1596 // having the same name and type, ignoring entities declared 1597 // outside the innermost enclosing namespace scope, the block 1598 // scope declaration declares that same entity and receives the 1599 // linkage of the previous declaration. 1600 DeclContext *OuterContext = DC->getLookupContext(); 1601 if (!OuterContext->isFunctionOrMethod()) 1602 // This rule only applies to block-scope declarations. 1603 return false; 1604 else { 1605 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1606 if (PrevOuterContext->isRecord()) 1607 // We found a member function: ignore it. 1608 return false; 1609 else { 1610 // Find the innermost enclosing namespace for the new and 1611 // previous declarations. 1612 while (!OuterContext->isFileContext()) 1613 OuterContext = OuterContext->getParent(); 1614 while (!PrevOuterContext->isFileContext()) 1615 PrevOuterContext = PrevOuterContext->getParent(); 1616 1617 // The previous declaration is in a different namespace, so it 1618 // isn't the same function. 1619 if (OuterContext->getPrimaryContext() != 1620 PrevOuterContext->getPrimaryContext()) 1621 return false; 1622 } 1623 } 1624 } 1625 1626 return true; 1627} 1628 1629NamedDecl* 1630Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1631 QualType R,NamedDecl* PrevDecl, bool& InvalidDecl, 1632 bool &Redeclaration) { 1633 DeclarationName Name = GetNameForDeclarator(D); 1634 1635 // Check that there are no default arguments (C++ only). 1636 if (getLangOptions().CPlusPlus) 1637 CheckExtraCXXDefaultArguments(D); 1638 1639 VarDecl *NewVD; 1640 VarDecl::StorageClass SC; 1641 switch (D.getDeclSpec().getStorageClassSpec()) { 1642 default: assert(0 && "Unknown storage class!"); 1643 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1644 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1645 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1646 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1647 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1648 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1649 case DeclSpec::SCS_mutable: 1650 // mutable can only appear on non-static class members, so it's always 1651 // an error here 1652 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1653 InvalidDecl = true; 1654 SC = VarDecl::None; 1655 break; 1656 } 1657 1658 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1659 if (!II) { 1660 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1661 << Name.getAsString(); 1662 return 0; 1663 } 1664 1665 DiagnoseFunctionSpecifiers(D); 1666 1667 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1668 if (!DC->isRecord() && S->getFnParent() == 0) { 1669 // C99 6.9p2: The storage-class specifiers auto and register shall not 1670 // appear in the declaration specifiers in an external declaration. 1671 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1672 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1673 InvalidDecl = true; 1674 } 1675 } 1676 if (DC->isRecord() && !CurContext->isRecord()) { 1677 // This is an out-of-line definition of a static data member. 1678 if (SC == VarDecl::Static) { 1679 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1680 diag::err_static_out_of_line) 1681 << CodeModificationHint::CreateRemoval( 1682 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1683 } else if (SC == VarDecl::None) 1684 SC = VarDecl::Static; 1685 } 1686 1687 // The variable can not 1688 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1689 II, R, SC, 1690 // FIXME: Move to DeclGroup... 1691 D.getDeclSpec().getSourceRange().getBegin()); 1692 NewVD->setThreadSpecified(ThreadSpecified); 1693 1694 // Set the lexical context. If the declarator has a C++ scope specifier, the 1695 // lexical context will be different from the semantic context. 1696 NewVD->setLexicalDeclContext(CurContext); 1697 1698 // Handle attributes prior to checking for duplicates in MergeVarDecl 1699 ProcessDeclAttributes(NewVD, D); 1700 1701 // Handle GNU asm-label extension (encoded as an attribute). 1702 if (Expr *E = (Expr*) D.getAsmLabel()) { 1703 // The parser guarantees this is a string. 1704 StringLiteral *SE = cast<StringLiteral>(E); 1705 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1706 SE->getByteLength()))); 1707 } 1708 1709 // If name lookup finds a previous declaration that is not in the 1710 // same scope as the new declaration, this may still be an 1711 // acceptable redeclaration. 1712 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1713 !(NewVD->hasLinkage() && 1714 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1715 PrevDecl = 0; 1716 1717 // Merge the decl with the existing one if appropriate. 1718 if (PrevDecl) { 1719 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1720 // The user tried to define a non-static data member 1721 // out-of-line (C++ [dcl.meaning]p1). 1722 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1723 << D.getCXXScopeSpec().getRange(); 1724 PrevDecl = 0; 1725 InvalidDecl = true; 1726 } 1727 } else if (D.getCXXScopeSpec().isSet()) { 1728 // No previous declaration in the qualifying scope. 1729 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1730 << Name << D.getCXXScopeSpec().getRange(); 1731 InvalidDecl = true; 1732 } 1733 1734 if (CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration)) 1735 InvalidDecl = true; 1736 1737 // If this is a locally-scoped extern C variable, update the map of 1738 // such variables. 1739 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1740 !InvalidDecl) 1741 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1742 1743 return NewVD; 1744} 1745 1746/// \brief Perform semantic checking on a newly-created variable 1747/// declaration. 1748/// 1749/// This routine performs all of the type-checking required for a 1750/// variable declaration once it has been build. It is used both to 1751/// check variables after they have been parsed and their declarators 1752/// have been translated into a declaration, and to check 1753/// 1754/// \returns true if an error was encountered, false otherwise. 1755bool Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1756 bool &Redeclaration) { 1757 bool Invalid = false; 1758 1759 QualType T = NewVD->getType(); 1760 1761 if (T->isObjCInterfaceType()) { 1762 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1763 Invalid = true; 1764 } 1765 1766 // The variable can not have an abstract class type. 1767 if (RequireNonAbstractType(NewVD->getLocation(), T, 1768 diag::err_abstract_type_in_decl, 1769 AbstractVariableType)) 1770 Invalid = true; 1771 1772 // Emit an error if an address space was applied to decl with local storage. 1773 // This includes arrays of objects with address space qualifiers, but not 1774 // automatic variables that point to other address spaces. 1775 // ISO/IEC TR 18037 S5.1.2 1776 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1777 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1778 Invalid = true; 1779 } 1780 1781 if (NewVD->hasLocalStorage() && T.isObjCGCWeak()) 1782 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1783 1784 bool isIllegalVLA = T->isVariableArrayType() && NewVD->hasGlobalStorage(); 1785 bool isIllegalVM = T->isVariablyModifiedType() && NewVD->hasLinkage(); 1786 if (isIllegalVLA || isIllegalVM) { 1787 bool SizeIsNegative; 1788 QualType FixedTy = 1789 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1790 if (!FixedTy.isNull()) { 1791 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1792 NewVD->setType(FixedTy); 1793 } else if (T->isVariableArrayType()) { 1794 Invalid = true; 1795 1796 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1797 // FIXME: This won't give the correct result for 1798 // int a[10][n]; 1799 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1800 1801 if (NewVD->isFileVarDecl()) 1802 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1803 << SizeRange; 1804 else if (NewVD->getStorageClass() == VarDecl::Static) 1805 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1806 << SizeRange; 1807 else 1808 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1809 << SizeRange; 1810 } else { 1811 Invalid = true; 1812 1813 if (NewVD->isFileVarDecl()) 1814 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1815 else 1816 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1817 } 1818 } 1819 1820 if (!PrevDecl && NewVD->isExternC(Context)) { 1821 // Since we did not find anything by this name and we're declaring 1822 // an extern "C" variable, look for a non-visible extern "C" 1823 // declaration with the same name. 1824 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1825 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1826 if (Pos != LocallyScopedExternalDecls.end()) 1827 PrevDecl = Pos->second; 1828 } 1829 1830 if (!Invalid && T->isVoidType() && !NewVD->hasExternalStorage()) { 1831 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1832 << T; 1833 Invalid = true; 1834 } 1835 1836 if (PrevDecl) { 1837 Redeclaration = true; 1838 if (MergeVarDecl(NewVD, PrevDecl)) 1839 Invalid = true; 1840 } 1841 1842 return NewVD->isInvalidDecl() || Invalid; 1843} 1844 1845NamedDecl* 1846Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1847 QualType R, NamedDecl* PrevDecl, 1848 bool IsFunctionDefinition, 1849 bool& InvalidDecl, bool &Redeclaration) { 1850 assert(R.getTypePtr()->isFunctionType()); 1851 1852 DeclarationName Name = GetNameForDeclarator(D); 1853 FunctionDecl::StorageClass SC = FunctionDecl::None; 1854 switch (D.getDeclSpec().getStorageClassSpec()) { 1855 default: assert(0 && "Unknown storage class!"); 1856 case DeclSpec::SCS_auto: 1857 case DeclSpec::SCS_register: 1858 case DeclSpec::SCS_mutable: 1859 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1860 diag::err_typecheck_sclass_func); 1861 InvalidDecl = true; 1862 break; 1863 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1864 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1865 case DeclSpec::SCS_static: { 1866 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1867 // C99 6.7.1p5: 1868 // The declaration of an identifier for a function that has 1869 // block scope shall have no explicit storage-class specifier 1870 // other than extern 1871 // See also (C++ [dcl.stc]p4). 1872 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1873 diag::err_static_block_func); 1874 SC = FunctionDecl::None; 1875 } else 1876 SC = FunctionDecl::Static; 1877 break; 1878 } 1879 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1880 } 1881 1882 bool isInline = D.getDeclSpec().isInlineSpecified(); 1883 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1884 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1885 1886 // Check that the return type is not an abstract class type. 1887 // For record types, this is done by the AbstractClassUsageDiagnoser once 1888 // the class has been completely parsed. 1889 if (!DC->isRecord() && 1890 RequireNonAbstractType(D.getIdentifierLoc(), 1891 R->getAsFunctionType()->getResultType(), 1892 diag::err_abstract_type_in_decl, 1893 AbstractReturnType)) 1894 InvalidDecl = true; 1895 1896 // Do not allow returning a objc interface by-value. 1897 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1898 Diag(D.getIdentifierLoc(), 1899 diag::err_object_cannot_be_passed_returned_by_value) << 0 1900 << R->getAsFunctionType()->getResultType(); 1901 InvalidDecl = true; 1902 } 1903 1904 bool isVirtualOkay = false; 1905 FunctionDecl *NewFD; 1906 if (D.getKind() == Declarator::DK_Constructor) { 1907 // This is a C++ constructor declaration. 1908 assert(DC->isRecord() && 1909 "Constructors can only be declared in a member context"); 1910 1911 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1912 1913 // Create the new declaration 1914 NewFD = CXXConstructorDecl::Create(Context, 1915 cast<CXXRecordDecl>(DC), 1916 D.getIdentifierLoc(), Name, R, 1917 isExplicit, isInline, 1918 /*isImplicitlyDeclared=*/false); 1919 1920 if (InvalidDecl) 1921 NewFD->setInvalidDecl(); 1922 } else if (D.getKind() == Declarator::DK_Destructor) { 1923 // This is a C++ destructor declaration. 1924 if (DC->isRecord()) { 1925 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1926 1927 NewFD = CXXDestructorDecl::Create(Context, 1928 cast<CXXRecordDecl>(DC), 1929 D.getIdentifierLoc(), Name, R, 1930 isInline, 1931 /*isImplicitlyDeclared=*/false); 1932 1933 if (InvalidDecl) 1934 NewFD->setInvalidDecl(); 1935 1936 isVirtualOkay = true; 1937 } else { 1938 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1939 1940 // Create a FunctionDecl to satisfy the function definition parsing 1941 // code path. 1942 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1943 Name, R, SC, isInline, 1944 /*hasPrototype=*/true, 1945 // FIXME: Move to DeclGroup... 1946 D.getDeclSpec().getSourceRange().getBegin()); 1947 InvalidDecl = true; 1948 NewFD->setInvalidDecl(); 1949 } 1950 } else if (D.getKind() == Declarator::DK_Conversion) { 1951 if (!DC->isRecord()) { 1952 Diag(D.getIdentifierLoc(), 1953 diag::err_conv_function_not_member); 1954 return 0; 1955 } else { 1956 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1957 1958 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1959 D.getIdentifierLoc(), Name, R, 1960 isInline, isExplicit); 1961 1962 if (InvalidDecl) 1963 NewFD->setInvalidDecl(); 1964 1965 isVirtualOkay = true; 1966 } 1967 } else if (DC->isRecord()) { 1968 // This is a C++ method declaration. 1969 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1970 D.getIdentifierLoc(), Name, R, 1971 (SC == FunctionDecl::Static), isInline); 1972 1973 isVirtualOkay = (SC != FunctionDecl::Static); 1974 } else { 1975 // Determine whether the function was written with a 1976 // prototype. This true when: 1977 // - we're in C++ (where every function has a prototype), 1978 // - there is a prototype in the declarator, or 1979 // - the type R of the function is some kind of typedef or other reference 1980 // to a type name (which eventually refers to a function type). 1981 bool HasPrototype = 1982 getLangOptions().CPlusPlus || 1983 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 1984 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 1985 1986 NewFD = FunctionDecl::Create(Context, DC, 1987 D.getIdentifierLoc(), 1988 Name, R, SC, isInline, HasPrototype, 1989 // FIXME: Move to DeclGroup... 1990 D.getDeclSpec().getSourceRange().getBegin()); 1991 } 1992 1993 // Set the lexical context. If the declarator has a C++ 1994 // scope specifier, the lexical context will be different 1995 // from the semantic context. 1996 NewFD->setLexicalDeclContext(CurContext); 1997 1998 // C++ [dcl.fct.spec]p5: 1999 // The virtual specifier shall only be used in declarations of 2000 // nonstatic class member functions that appear within a 2001 // member-specification of a class declaration; see 10.3. 2002 // 2003 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2004 // function is also virtual if it overrides an already virtual 2005 // function. This is important to do here because it's part of the 2006 // declaration. 2007 if (isVirtual && !InvalidDecl) { 2008 if (!isVirtualOkay) { 2009 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2010 diag::err_virtual_non_function); 2011 } else if (!CurContext->isRecord()) { 2012 // 'virtual' was specified outside of the class. 2013 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2014 << CodeModificationHint::CreateRemoval( 2015 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2016 } else { 2017 // Okay: Add virtual to the method. 2018 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2019 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2020 CurClass->setAggregate(false); 2021 CurClass->setPOD(false); 2022 CurClass->setPolymorphic(true); 2023 } 2024 } 2025 2026 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2027 !CurContext->isRecord()) { 2028 // C++ [class.static]p1: 2029 // A data or function member of a class may be declared static 2030 // in a class definition, in which case it is a static member of 2031 // the class. 2032 2033 // Complain about the 'static' specifier if it's on an out-of-line 2034 // member function definition. 2035 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2036 diag::err_static_out_of_line) 2037 << CodeModificationHint::CreateRemoval( 2038 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2039 } 2040 2041 // Handle GNU asm-label extension (encoded as an attribute). 2042 if (Expr *E = (Expr*) D.getAsmLabel()) { 2043 // The parser guarantees this is a string. 2044 StringLiteral *SE = cast<StringLiteral>(E); 2045 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2046 SE->getByteLength()))); 2047 } 2048 2049 // Copy the parameter declarations from the declarator D to 2050 // the function declaration NewFD, if they are available. 2051 if (D.getNumTypeObjects() > 0) { 2052 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2053 2054 // Create Decl objects for each parameter, adding them to the 2055 // FunctionDecl. 2056 llvm::SmallVector<ParmVarDecl*, 16> Params; 2057 2058 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2059 // function that takes no arguments, not a function that takes a 2060 // single void argument. 2061 // We let through "const void" here because Sema::GetTypeForDeclarator 2062 // already checks for that case. 2063 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2064 FTI.ArgInfo[0].Param && 2065 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2066 // empty arg list, don't push any params. 2067 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2068 2069 // In C++, the empty parameter-type-list must be spelled "void"; a 2070 // typedef of void is not permitted. 2071 if (getLangOptions().CPlusPlus && 2072 Param->getType().getUnqualifiedType() != Context.VoidTy) { 2073 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2074 } 2075 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2076 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2077 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2078 } 2079 2080 NewFD->setParams(Context, &Params[0], Params.size()); 2081 } else if (R->getAsTypedefType()) { 2082 // When we're declaring a function with a typedef, as in the 2083 // following example, we'll need to synthesize (unnamed) 2084 // parameters for use in the declaration. 2085 // 2086 // @code 2087 // typedef void fn(int); 2088 // fn f; 2089 // @endcode 2090 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 2091 if (!FT) { 2092 // This is a typedef of a function with no prototype, so we 2093 // don't need to do anything. 2094 } else if ((FT->getNumArgs() == 0) || 2095 (FT->getNumArgs() == 1 && !FT->isVariadic() && 2096 FT->getArgType(0)->isVoidType())) { 2097 // This is a zero-argument function. We don't need to do anything. 2098 } else { 2099 // Synthesize a parameter for each argument type. 2100 llvm::SmallVector<ParmVarDecl*, 16> Params; 2101 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 2102 ArgType != FT->arg_type_end(); ++ArgType) { 2103 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2104 SourceLocation(), 0, 2105 *ArgType, VarDecl::None, 2106 0); 2107 Param->setImplicit(); 2108 Params.push_back(Param); 2109 } 2110 2111 NewFD->setParams(Context, &Params[0], Params.size()); 2112 } 2113 } 2114 2115 // If name lookup finds a previous declaration that is not in the 2116 // same scope as the new declaration, this may still be an 2117 // acceptable redeclaration. 2118 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2119 !(NewFD->hasLinkage() && 2120 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2121 PrevDecl = 0; 2122 2123 // Perform semantic checking on the function declaration. 2124 bool OverloadableAttrRequired = false; // FIXME: HACK! 2125 if (CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2126 /*FIXME:*/OverloadableAttrRequired)) 2127 InvalidDecl = true; 2128 2129 if (D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2130 // An out-of-line member function declaration must also be a 2131 // definition (C++ [dcl.meaning]p1). 2132 if (!IsFunctionDefinition) { 2133 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2134 << D.getCXXScopeSpec().getRange(); 2135 InvalidDecl = true; 2136 } else if (!Redeclaration) { 2137 // The user tried to provide an out-of-line definition for a 2138 // function that is a member of a class or namespace, but there 2139 // was no such member function declared (C++ [class.mfct]p2, 2140 // C++ [namespace.memdef]p2). For example: 2141 // 2142 // class X { 2143 // void f() const; 2144 // }; 2145 // 2146 // void X::f() { } // ill-formed 2147 // 2148 // Complain about this problem, and attempt to suggest close 2149 // matches (e.g., those that differ only in cv-qualifiers and 2150 // whether the parameter types are references). 2151 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2152 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2153 InvalidDecl = true; 2154 2155 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2156 true); 2157 assert(!Prev.isAmbiguous() && 2158 "Cannot have an ambiguity in previous-declaration lookup"); 2159 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2160 Func != FuncEnd; ++Func) { 2161 if (isa<FunctionDecl>(*Func) && 2162 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2163 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2164 } 2165 2166 PrevDecl = 0; 2167 } 2168 } 2169 2170 // Handle attributes. We need to have merged decls when handling attributes 2171 // (for example to check for conflicts, etc). 2172 // FIXME: This needs to happen before we merge declarations. Then, 2173 // let attribute merging cope with attribute conflicts. 2174 ProcessDeclAttributes(NewFD, D); 2175 AddKnownFunctionAttributes(NewFD); 2176 2177 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2178 // If a function name is overloadable in C, then every function 2179 // with that name must be marked "overloadable". 2180 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2181 << Redeclaration << NewFD; 2182 if (PrevDecl) 2183 Diag(PrevDecl->getLocation(), 2184 diag::note_attribute_overloadable_prev_overload); 2185 NewFD->addAttr(::new (Context) OverloadableAttr()); 2186 } 2187 2188 // If this is a locally-scoped extern C function, update the 2189 // map of such names. 2190 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2191 && !InvalidDecl) 2192 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2193 2194 return NewFD; 2195} 2196 2197/// \brief Perform semantic checking of a new function declaration. 2198/// 2199/// Performs semantic analysis of the new function declaration 2200/// NewFD. This routine performs all semantic checking that does not 2201/// require the actual declarator involved in the declaration, and is 2202/// used both for the declaration of functions as they are parsed 2203/// (called via ActOnDeclarator) and for the declaration of functions 2204/// that have been instantiated via C++ template instantiation (called 2205/// via InstantiateDecl). 2206/// 2207/// \returns true if there was an error, false otherwise. 2208bool Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2209 bool &Redeclaration, 2210 bool &OverloadableAttrRequired) { 2211 bool InvalidDecl = false; 2212 2213 // Semantic checking for this function declaration (in isolation). 2214 if (getLangOptions().CPlusPlus) { 2215 // C++-specific checks. 2216 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 2217 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 2218 else if (isa<CXXDestructorDecl>(NewFD)) { 2219 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2220 Record->setUserDeclaredDestructor(true); 2221 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2222 // user-defined destructor. 2223 Record->setPOD(false); 2224 } else if (CXXConversionDecl *Conversion 2225 = dyn_cast<CXXConversionDecl>(NewFD)) 2226 ActOnConversionDeclarator(Conversion); 2227 2228 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2229 if (NewFD->isOverloadedOperator() && 2230 CheckOverloadedOperatorDeclaration(NewFD)) 2231 InvalidDecl = true; 2232 } 2233 2234 // Check for a previous declaration of this name. 2235 if (!PrevDecl && NewFD->isExternC(Context)) { 2236 // Since we did not find anything by this name and we're declaring 2237 // an extern "C" function, look for a non-visible extern "C" 2238 // declaration with the same name. 2239 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2240 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2241 if (Pos != LocallyScopedExternalDecls.end()) 2242 PrevDecl = Pos->second; 2243 } 2244 2245 // Merge or overload the declaration with an existing declaration of 2246 // the same name, if appropriate. 2247 if (PrevDecl) { 2248 // Determine whether NewFD is an overload of PrevDecl or 2249 // a declaration that requires merging. If it's an overload, 2250 // there's no more work to do here; we'll just add the new 2251 // function to the scope. 2252 OverloadedFunctionDecl::function_iterator MatchedDecl; 2253 2254 if (!getLangOptions().CPlusPlus && 2255 AllowOverloadingOfFunction(PrevDecl, Context)) { 2256 OverloadableAttrRequired = true; 2257 2258 // Functions marked "overloadable" must have a prototype (that 2259 // we can't get through declaration merging). 2260 if (!NewFD->getType()->getAsFunctionProtoType()) { 2261 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2262 << NewFD; 2263 InvalidDecl = true; 2264 Redeclaration = true; 2265 2266 // Turn this into a variadic function with no parameters. 2267 QualType R = Context.getFunctionType( 2268 NewFD->getType()->getAsFunctionType()->getResultType(), 2269 0, 0, true, 0); 2270 NewFD->setType(R); 2271 } 2272 } 2273 2274 if (PrevDecl && 2275 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2276 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2277 Redeclaration = true; 2278 Decl *OldDecl = PrevDecl; 2279 2280 // If PrevDecl was an overloaded function, extract the 2281 // FunctionDecl that matched. 2282 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2283 OldDecl = *MatchedDecl; 2284 2285 // NewFD and OldDecl represent declarations that need to be 2286 // merged. 2287 if (MergeFunctionDecl(NewFD, OldDecl)) 2288 InvalidDecl = true; 2289 2290 if (!InvalidDecl) 2291 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2292 } 2293 } 2294 2295 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) { 2296 // In C++, check default arguments now that we have merged decls. Unless 2297 // the lexical context is the class, because in this case this is done 2298 // during delayed parsing anyway. 2299 CheckCXXDefaultArguments(NewFD); 2300 } 2301 2302 return InvalidDecl || NewFD->isInvalidDecl(); 2303} 2304 2305bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2306 // FIXME: Need strict checking. In C89, we need to check for 2307 // any assignment, increment, decrement, function-calls, or 2308 // commas outside of a sizeof. In C99, it's the same list, 2309 // except that the aforementioned are allowed in unevaluated 2310 // expressions. Everything else falls under the 2311 // "may accept other forms of constant expressions" exception. 2312 // (We never end up here for C++, so the constant expression 2313 // rules there don't matter.) 2314 if (Init->isConstantInitializer(Context)) 2315 return false; 2316 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2317 << Init->getSourceRange(); 2318 return true; 2319} 2320 2321void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2322 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2323} 2324 2325/// AddInitializerToDecl - Adds the initializer Init to the 2326/// declaration dcl. If DirectInit is true, this is C++ direct 2327/// initialization rather than copy initialization. 2328void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2329 Decl *RealDecl = dcl.getAs<Decl>(); 2330 // If there is no declaration, there was an error parsing it. Just ignore 2331 // the initializer. 2332 if (RealDecl == 0) 2333 return; 2334 2335 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2336 // With declarators parsed the way they are, the parser cannot 2337 // distinguish between a normal initializer and a pure-specifier. 2338 // Thus this grotesque test. 2339 IntegerLiteral *IL; 2340 Expr *Init = static_cast<Expr *>(init.get()); 2341 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2342 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2343 if (Method->isVirtual()) { 2344 Method->setPure(); 2345 2346 // A class is abstract if at least one function is pure virtual. 2347 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2348 } else if (!Method->isInvalidDecl()) { 2349 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2350 << Method->getDeclName() << Init->getSourceRange(); 2351 Method->setInvalidDecl(); 2352 } 2353 } else { 2354 Diag(Method->getLocation(), diag::err_member_function_initialization) 2355 << Method->getDeclName() << Init->getSourceRange(); 2356 Method->setInvalidDecl(); 2357 } 2358 return; 2359 } 2360 2361 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2362 if (!VDecl) { 2363 if (getLangOptions().CPlusPlus && 2364 RealDecl->getLexicalDeclContext()->isRecord() && 2365 isa<NamedDecl>(RealDecl)) 2366 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2367 << cast<NamedDecl>(RealDecl)->getDeclName(); 2368 else 2369 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2370 RealDecl->setInvalidDecl(); 2371 return; 2372 } 2373 2374 const VarDecl *Def = 0; 2375 if (VDecl->getDefinition(Def)) { 2376 Diag(VDecl->getLocation(), diag::err_redefinition) 2377 << VDecl->getDeclName(); 2378 Diag(Def->getLocation(), diag::note_previous_definition); 2379 VDecl->setInvalidDecl(); 2380 return; 2381 } 2382 2383 // Take ownership of the expression, now that we're sure we have somewhere 2384 // to put it. 2385 Expr *Init = static_cast<Expr *>(init.release()); 2386 assert(Init && "missing initializer"); 2387 2388 // Get the decls type and save a reference for later, since 2389 // CheckInitializerTypes may change it. 2390 QualType DclT = VDecl->getType(), SavT = DclT; 2391 if (VDecl->isBlockVarDecl()) { 2392 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2393 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2394 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2395 VDecl->setInvalidDecl(); 2396 } else if (!VDecl->isInvalidDecl()) { 2397 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2398 VDecl->getDeclName(), DirectInit)) 2399 VDecl->setInvalidDecl(); 2400 2401 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2402 // Don't check invalid declarations to avoid emitting useless diagnostics. 2403 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2404 if (SC == VarDecl::Static) // C99 6.7.8p4. 2405 CheckForConstantInitializer(Init, DclT); 2406 } 2407 } 2408 } else if (VDecl->isStaticDataMember() && 2409 VDecl->getLexicalDeclContext()->isRecord()) { 2410 // This is an in-class initialization for a static data member, e.g., 2411 // 2412 // struct S { 2413 // static const int value = 17; 2414 // }; 2415 2416 // Attach the initializer 2417 VDecl->setInit(Init); 2418 2419 // C++ [class.mem]p4: 2420 // A member-declarator can contain a constant-initializer only 2421 // if it declares a static member (9.4) of const integral or 2422 // const enumeration type, see 9.4.2. 2423 QualType T = VDecl->getType(); 2424 if (!T->isDependentType() && 2425 (!Context.getCanonicalType(T).isConstQualified() || 2426 !T->isIntegralType())) { 2427 Diag(VDecl->getLocation(), diag::err_member_initialization) 2428 << VDecl->getDeclName() << Init->getSourceRange(); 2429 VDecl->setInvalidDecl(); 2430 } else { 2431 // C++ [class.static.data]p4: 2432 // If a static data member is of const integral or const 2433 // enumeration type, its declaration in the class definition 2434 // can specify a constant-initializer which shall be an 2435 // integral constant expression (5.19). 2436 if (!Init->isTypeDependent() && 2437 !Init->getType()->isIntegralType()) { 2438 // We have a non-dependent, non-integral or enumeration type. 2439 Diag(Init->getSourceRange().getBegin(), 2440 diag::err_in_class_initializer_non_integral_type) 2441 << Init->getType() << Init->getSourceRange(); 2442 VDecl->setInvalidDecl(); 2443 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2444 // Check whether the expression is a constant expression. 2445 llvm::APSInt Value; 2446 SourceLocation Loc; 2447 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2448 Diag(Loc, diag::err_in_class_initializer_non_constant) 2449 << Init->getSourceRange(); 2450 VDecl->setInvalidDecl(); 2451 } else if (!VDecl->getType()->isDependentType()) 2452 ImpCastExprToType(Init, VDecl->getType()); 2453 } 2454 } 2455 } else if (VDecl->isFileVarDecl()) { 2456 if (VDecl->getStorageClass() == VarDecl::Extern) 2457 Diag(VDecl->getLocation(), diag::warn_extern_init); 2458 if (!VDecl->isInvalidDecl()) 2459 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2460 VDecl->getDeclName(), DirectInit)) 2461 VDecl->setInvalidDecl(); 2462 2463 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2464 // Don't check invalid declarations to avoid emitting useless diagnostics. 2465 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2466 // C99 6.7.8p4. All file scoped initializers need to be constant. 2467 CheckForConstantInitializer(Init, DclT); 2468 } 2469 } 2470 // If the type changed, it means we had an incomplete type that was 2471 // completed by the initializer. For example: 2472 // int ary[] = { 1, 3, 5 }; 2473 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2474 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2475 VDecl->setType(DclT); 2476 Init->setType(DclT); 2477 } 2478 2479 // Attach the initializer to the decl. 2480 VDecl->setInit(Init); 2481 return; 2482} 2483 2484void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2485 Decl *RealDecl = dcl.getAs<Decl>(); 2486 2487 // If there is no declaration, there was an error parsing it. Just ignore it. 2488 if (RealDecl == 0) 2489 return; 2490 2491 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2492 QualType Type = Var->getType(); 2493 // C++ [dcl.init.ref]p3: 2494 // The initializer can be omitted for a reference only in a 2495 // parameter declaration (8.3.5), in the declaration of a 2496 // function return type, in the declaration of a class member 2497 // within its class declaration (9.2), and where the extern 2498 // specifier is explicitly used. 2499 if (Type->isReferenceType() && 2500 Var->getStorageClass() != VarDecl::Extern && 2501 Var->getStorageClass() != VarDecl::PrivateExtern) { 2502 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2503 << Var->getDeclName() 2504 << SourceRange(Var->getLocation(), Var->getLocation()); 2505 Var->setInvalidDecl(); 2506 return; 2507 } 2508 2509 // C++ [dcl.init]p9: 2510 // 2511 // If no initializer is specified for an object, and the object 2512 // is of (possibly cv-qualified) non-POD class type (or array 2513 // thereof), the object shall be default-initialized; if the 2514 // object is of const-qualified type, the underlying class type 2515 // shall have a user-declared default constructor. 2516 if (getLangOptions().CPlusPlus) { 2517 QualType InitType = Type; 2518 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2519 InitType = Array->getElementType(); 2520 if (Var->getStorageClass() != VarDecl::Extern && 2521 Var->getStorageClass() != VarDecl::PrivateExtern && 2522 InitType->isRecordType()) { 2523 const CXXConstructorDecl *Constructor = 0; 2524 if (!RequireCompleteType(Var->getLocation(), InitType, 2525 diag::err_invalid_incomplete_type_use)) 2526 Constructor 2527 = PerformInitializationByConstructor(InitType, 0, 0, 2528 Var->getLocation(), 2529 SourceRange(Var->getLocation(), 2530 Var->getLocation()), 2531 Var->getDeclName(), 2532 IK_Default); 2533 if (!Constructor) 2534 Var->setInvalidDecl(); 2535 } 2536 } 2537 2538#if 0 2539 // FIXME: Temporarily disabled because we are not properly parsing 2540 // linkage specifications on declarations, e.g., 2541 // 2542 // extern "C" const CGPoint CGPointerZero; 2543 // 2544 // C++ [dcl.init]p9: 2545 // 2546 // If no initializer is specified for an object, and the 2547 // object is of (possibly cv-qualified) non-POD class type (or 2548 // array thereof), the object shall be default-initialized; if 2549 // the object is of const-qualified type, the underlying class 2550 // type shall have a user-declared default 2551 // constructor. Otherwise, if no initializer is specified for 2552 // an object, the object and its subobjects, if any, have an 2553 // indeterminate initial value; if the object or any of its 2554 // subobjects are of const-qualified type, the program is 2555 // ill-formed. 2556 // 2557 // This isn't technically an error in C, so we don't diagnose it. 2558 // 2559 // FIXME: Actually perform the POD/user-defined default 2560 // constructor check. 2561 if (getLangOptions().CPlusPlus && 2562 Context.getCanonicalType(Type).isConstQualified() && 2563 Var->getStorageClass() != VarDecl::Extern) 2564 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2565 << Var->getName() 2566 << SourceRange(Var->getLocation(), Var->getLocation()); 2567#endif 2568 } 2569} 2570 2571Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2572 unsigned NumDecls) { 2573 llvm::SmallVector<Decl*, 8> Decls; 2574 2575 for (unsigned i = 0; i != NumDecls; ++i) 2576 if (Decl *D = Group[i].getAs<Decl>()) 2577 Decls.push_back(D); 2578 2579 // Perform semantic analysis that depends on having fully processed both 2580 // the declarator and initializer. 2581 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2582 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2583 if (!IDecl) 2584 continue; 2585 QualType T = IDecl->getType(); 2586 2587 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2588 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2589 if (IDecl->isBlockVarDecl() && 2590 IDecl->getStorageClass() != VarDecl::Extern) { 2591 if (!IDecl->isInvalidDecl() && 2592 RequireCompleteType(IDecl->getLocation(), T, 2593 diag::err_typecheck_decl_incomplete_type)) 2594 IDecl->setInvalidDecl(); 2595 } 2596 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2597 // object that has file scope without an initializer, and without a 2598 // storage-class specifier or with the storage-class specifier "static", 2599 // constitutes a tentative definition. Note: A tentative definition with 2600 // external linkage is valid (C99 6.2.2p5). 2601 if (IDecl->isTentativeDefinition(Context)) { 2602 QualType CheckType = T; 2603 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2604 2605 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2606 if (ArrayT) { 2607 CheckType = ArrayT->getElementType(); 2608 DiagID = diag::err_illegal_decl_array_incomplete_type; 2609 } 2610 2611 if (IDecl->isInvalidDecl()) { 2612 // Do nothing with invalid declarations 2613 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2614 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2615 // C99 6.9.2p3: If the declaration of an identifier for an object is 2616 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2617 // declared type shall not be an incomplete type. 2618 IDecl->setInvalidDecl(); 2619 } 2620 } 2621 } 2622 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2623 &Decls[0], Decls.size())); 2624} 2625 2626 2627/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2628/// to introduce parameters into function prototype scope. 2629Sema::DeclPtrTy 2630Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2631 const DeclSpec &DS = D.getDeclSpec(); 2632 2633 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2634 VarDecl::StorageClass StorageClass = VarDecl::None; 2635 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2636 StorageClass = VarDecl::Register; 2637 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2638 Diag(DS.getStorageClassSpecLoc(), 2639 diag::err_invalid_storage_class_in_func_decl); 2640 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2641 } 2642 if (DS.isThreadSpecified()) { 2643 Diag(DS.getThreadSpecLoc(), 2644 diag::err_invalid_storage_class_in_func_decl); 2645 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2646 } 2647 DiagnoseFunctionSpecifiers(D); 2648 2649 // Check that there are no default arguments inside the type of this 2650 // parameter (C++ only). 2651 if (getLangOptions().CPlusPlus) 2652 CheckExtraCXXDefaultArguments(D); 2653 2654 // In this context, we *do not* check D.getInvalidType(). If the declarator 2655 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2656 // though it will not reflect the user specified type. 2657 QualType parmDeclType = GetTypeForDeclarator(D, S); 2658 2659 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2660 2661 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2662 // Can this happen for params? We already checked that they don't conflict 2663 // among each other. Here they can only shadow globals, which is ok. 2664 IdentifierInfo *II = D.getIdentifier(); 2665 if (II) { 2666 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2667 if (PrevDecl->isTemplateParameter()) { 2668 // Maybe we will complain about the shadowed template parameter. 2669 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2670 // Just pretend that we didn't see the previous declaration. 2671 PrevDecl = 0; 2672 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2673 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2674 2675 // Recover by removing the name 2676 II = 0; 2677 D.SetIdentifier(0, D.getIdentifierLoc()); 2678 } 2679 } 2680 } 2681 2682 // Parameters can not be abstract class types. 2683 // For record types, this is done by the AbstractClassUsageDiagnoser once 2684 // the class has been completely parsed. 2685 if (!CurContext->isRecord() && 2686 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2687 diag::err_abstract_type_in_decl, 2688 AbstractParamType)) 2689 D.setInvalidType(true); 2690 2691 QualType T = adjustParameterType(parmDeclType); 2692 2693 ParmVarDecl *New; 2694 if (T == parmDeclType) // parameter type did not need adjustment 2695 New = ParmVarDecl::Create(Context, CurContext, 2696 D.getIdentifierLoc(), II, 2697 parmDeclType, StorageClass, 2698 0); 2699 else // keep track of both the adjusted and unadjusted types 2700 New = OriginalParmVarDecl::Create(Context, CurContext, 2701 D.getIdentifierLoc(), II, T, 2702 parmDeclType, StorageClass, 0); 2703 2704 if (D.getInvalidType()) 2705 New->setInvalidDecl(); 2706 2707 // Parameter declarators cannot be interface types. All ObjC objects are 2708 // passed by reference. 2709 if (T->isObjCInterfaceType()) { 2710 Diag(D.getIdentifierLoc(), 2711 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2712 New->setInvalidDecl(); 2713 } 2714 2715 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2716 if (D.getCXXScopeSpec().isSet()) { 2717 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2718 << D.getCXXScopeSpec().getRange(); 2719 New->setInvalidDecl(); 2720 } 2721 2722 // Add the parameter declaration into this scope. 2723 S->AddDecl(DeclPtrTy::make(New)); 2724 if (II) 2725 IdResolver.AddDecl(New); 2726 2727 ProcessDeclAttributes(New, D); 2728 return DeclPtrTy::make(New); 2729} 2730 2731void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2732 SourceLocation LocAfterDecls) { 2733 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2734 "Not a function declarator!"); 2735 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2736 2737 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2738 // for a K&R function. 2739 if (!FTI.hasPrototype) { 2740 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2741 --i; 2742 if (FTI.ArgInfo[i].Param == 0) { 2743 std::string Code = " int "; 2744 Code += FTI.ArgInfo[i].Ident->getName(); 2745 Code += ";\n"; 2746 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2747 << FTI.ArgInfo[i].Ident 2748 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2749 2750 // Implicitly declare the argument as type 'int' for lack of a better 2751 // type. 2752 DeclSpec DS; 2753 const char* PrevSpec; // unused 2754 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2755 PrevSpec); 2756 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2757 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2758 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2759 } 2760 } 2761 } 2762} 2763 2764Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2765 Declarator &D) { 2766 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2767 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2768 "Not a function declarator!"); 2769 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2770 2771 if (FTI.hasPrototype) { 2772 // FIXME: Diagnose arguments without names in C. 2773 } 2774 2775 Scope *ParentScope = FnBodyScope->getParent(); 2776 2777 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2778 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2779} 2780 2781Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2782 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2783 2784 // See if this is a redefinition. 2785 const FunctionDecl *Definition; 2786 if (FD->getBody(Definition)) { 2787 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2788 Diag(Definition->getLocation(), diag::note_previous_definition); 2789 } 2790 2791 // Builtin functions cannot be defined. 2792 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2793 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2794 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2795 FD->setInvalidDecl(); 2796 } 2797 } 2798 2799 // The return type of a function definition must be complete 2800 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2801 QualType ResultType = FD->getResultType(); 2802 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2803 RequireCompleteType(FD->getLocation(), ResultType, 2804 diag::err_func_def_incomplete_result)) 2805 FD->setInvalidDecl(); 2806 2807 // GNU warning -Wmissing-prototypes: 2808 // Warn if a global function is defined without a previous 2809 // prototype declaration. This warning is issued even if the 2810 // definition itself provides a prototype. The aim is to detect 2811 // global functions that fail to be declared in header files. 2812 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2813 !FD->isMain()) { 2814 bool MissingPrototype = true; 2815 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2816 Prev; Prev = Prev->getPreviousDeclaration()) { 2817 // Ignore any declarations that occur in function or method 2818 // scope, because they aren't visible from the header. 2819 if (Prev->getDeclContext()->isFunctionOrMethod()) 2820 continue; 2821 2822 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2823 break; 2824 } 2825 2826 if (MissingPrototype) 2827 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2828 } 2829 2830 PushDeclContext(FnBodyScope, FD); 2831 2832 // Check the validity of our function parameters 2833 CheckParmsForFunctionDef(FD); 2834 2835 // Introduce our parameters into the function scope 2836 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2837 ParmVarDecl *Param = FD->getParamDecl(p); 2838 Param->setOwningFunction(FD); 2839 2840 // If this has an identifier, add it to the scope stack. 2841 if (Param->getIdentifier()) 2842 PushOnScopeChains(Param, FnBodyScope); 2843 } 2844 2845 // Checking attributes of current function definition 2846 // dllimport attribute. 2847 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2848 // dllimport attribute cannot be applied to definition. 2849 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2850 Diag(FD->getLocation(), 2851 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2852 << "dllimport"; 2853 FD->setInvalidDecl(); 2854 return DeclPtrTy::make(FD); 2855 } else { 2856 // If a symbol previously declared dllimport is later defined, the 2857 // attribute is ignored in subsequent references, and a warning is 2858 // emitted. 2859 Diag(FD->getLocation(), 2860 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2861 << FD->getNameAsCString() << "dllimport"; 2862 } 2863 } 2864 return DeclPtrTy::make(FD); 2865} 2866 2867static bool StatementCreatesScope(Stmt* S) { 2868 DeclStmt *DS = dyn_cast<DeclStmt>(S); 2869 if (DS == 0) return false; 2870 2871 for (DeclStmt::decl_iterator I = DS->decl_begin(), E = DS->decl_end(); 2872 I != E; ++I) { 2873 if (VarDecl *D = dyn_cast<VarDecl>(*I)) { 2874 if (D->getType()->isVariablyModifiedType() || 2875 D->hasAttr<CleanupAttr>()) 2876 return true; 2877 } else if (TypedefDecl *D = dyn_cast<TypedefDecl>(*I)) { 2878 if (D->getUnderlyingType()->isVariablyModifiedType()) 2879 return true; 2880 } 2881 } 2882 2883 return false; 2884} 2885 2886 2887void Sema::RecursiveCalcLabelScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2888 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2889 std::vector<void*>& ScopeStack, 2890 Stmt* CurStmt, 2891 Stmt* ParentCompoundStmt) { 2892 for (Stmt::child_iterator i = CurStmt->child_begin(); 2893 i != CurStmt->child_end(); ++i) { 2894 if (!*i) continue; 2895 if (StatementCreatesScope(*i)) { 2896 ScopeStack.push_back(*i); 2897 PopScopeMap[*i] = ParentCompoundStmt; 2898 } else if (isa<LabelStmt>(CurStmt)) { 2899 LabelScopeMap[CurStmt] = ScopeStack.size() ? ScopeStack.back() : 0; 2900 } 2901 if (isa<DeclStmt>(*i)) continue; 2902 Stmt* CurCompound = isa<CompoundStmt>(*i) ? *i : ParentCompoundStmt; 2903 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, 2904 *i, CurCompound); 2905 } 2906 2907 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2908 ScopeStack.pop_back(); 2909 } 2910} 2911 2912void Sema::RecursiveCalcJumpScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2913 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2914 llvm::DenseMap<Stmt*, void*>& GotoScopeMap, 2915 std::vector<void*>& ScopeStack, 2916 Stmt* CurStmt) { 2917 for (Stmt::child_iterator i = CurStmt->child_begin(); 2918 i != CurStmt->child_end(); ++i) { 2919 if (!*i) continue; 2920 if (StatementCreatesScope(*i)) { 2921 ScopeStack.push_back(*i); 2922 } else if (GotoStmt* GS = dyn_cast<GotoStmt>(*i)) { 2923 void* LScope = LabelScopeMap[GS->getLabel()]; 2924 if (LScope) { 2925 bool foundScopeInStack = false; 2926 for (unsigned i = ScopeStack.size(); i > 0; --i) { 2927 if (LScope == ScopeStack[i-1]) { 2928 foundScopeInStack = true; 2929 break; 2930 } 2931 } 2932 if (!foundScopeInStack) { 2933 Diag(GS->getSourceRange().getBegin(), diag::err_goto_into_scope); 2934 } 2935 } 2936 } 2937 if (isa<DeclStmt>(*i)) continue; 2938 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, 2939 ScopeStack, *i); 2940 } 2941 2942 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2943 ScopeStack.pop_back(); 2944 } 2945} 2946 2947Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 2948 Decl *dcl = D.getAs<Decl>(); 2949 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2950 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2951 FD->setBody(cast<CompoundStmt>(Body)); 2952 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2953 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2954 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2955 MD->setBody(cast<CompoundStmt>(Body)); 2956 } else { 2957 Body->Destroy(Context); 2958 return DeclPtrTy(); 2959 } 2960 PopDeclContext(); 2961 // Verify and clean out per-function state. 2962 2963 bool HaveLabels = !LabelMap.empty(); 2964 // Check goto/label use. 2965 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2966 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2967 // Verify that we have no forward references left. If so, there was a goto 2968 // or address of a label taken, but no definition of it. Label fwd 2969 // definitions are indicated with a null substmt. 2970 if (I->second->getSubStmt() == 0) { 2971 LabelStmt *L = I->second; 2972 // Emit error. 2973 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2974 2975 // At this point, we have gotos that use the bogus label. Stitch it into 2976 // the function body so that they aren't leaked and that the AST is well 2977 // formed. 2978 if (Body) { 2979#if 0 2980 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2981 // and the AST is malformed anyway. We should just blow away 'L'. 2982 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2983 cast<CompoundStmt>(Body)->push_back(L); 2984#else 2985 L->Destroy(Context); 2986#endif 2987 } else { 2988 // The whole function wasn't parsed correctly, just delete this. 2989 L->Destroy(Context); 2990 } 2991 } 2992 } 2993 LabelMap.clear(); 2994 2995 if (!Body) return D; 2996 2997 if (HaveLabels) { 2998 llvm::DenseMap<Stmt*, void*> LabelScopeMap; 2999 llvm::DenseMap<void*, Stmt*> PopScopeMap; 3000 llvm::DenseMap<Stmt*, void*> GotoScopeMap; 3001 std::vector<void*> ScopeStack; 3002 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, Body, Body); 3003 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, ScopeStack, Body); 3004 } 3005 3006 return D; 3007} 3008 3009/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3010/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3011NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3012 IdentifierInfo &II, Scope *S) { 3013 // Before we produce a declaration for an implicitly defined 3014 // function, see whether there was a locally-scoped declaration of 3015 // this name as a function or variable. If so, use that 3016 // (non-visible) declaration, and complain about it. 3017 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3018 = LocallyScopedExternalDecls.find(&II); 3019 if (Pos != LocallyScopedExternalDecls.end()) { 3020 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3021 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3022 return Pos->second; 3023 } 3024 3025 // Extension in C99. Legal in C90, but warn about it. 3026 if (getLangOptions().C99) 3027 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3028 else 3029 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3030 3031 // FIXME: handle stuff like: 3032 // void foo() { extern float X(); } 3033 // void bar() { X(); } <-- implicit decl for X in another scope. 3034 3035 // Set a Declarator for the implicit definition: int foo(); 3036 const char *Dummy; 3037 DeclSpec DS; 3038 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3039 Error = Error; // Silence warning. 3040 assert(!Error && "Error setting up implicit decl!"); 3041 Declarator D(DS, Declarator::BlockContext); 3042 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3043 0, 0, 0, Loc, D), 3044 SourceLocation()); 3045 D.SetIdentifier(&II, Loc); 3046 3047 // Insert this function into translation-unit scope. 3048 3049 DeclContext *PrevDC = CurContext; 3050 CurContext = Context.getTranslationUnitDecl(); 3051 3052 FunctionDecl *FD = 3053 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3054 FD->setImplicit(); 3055 3056 CurContext = PrevDC; 3057 3058 AddKnownFunctionAttributes(FD); 3059 3060 return FD; 3061} 3062 3063/// \brief Adds any function attributes that we know a priori based on 3064/// the declaration of this function. 3065/// 3066/// These attributes can apply both to implicitly-declared builtins 3067/// (like __builtin___printf_chk) or to library-declared functions 3068/// like NSLog or printf. 3069void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3070 if (FD->isInvalidDecl()) 3071 return; 3072 3073 // If this is a built-in function, map its builtin attributes to 3074 // actual attributes. 3075 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3076 // Handle printf-formatting attributes. 3077 unsigned FormatIdx; 3078 bool HasVAListArg; 3079 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3080 if (!FD->getAttr<FormatAttr>()) 3081 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3082 FormatIdx + 2)); 3083 } 3084 3085 // Mark const if we don't care about errno and that is the only 3086 // thing preventing the function from being const. This allows 3087 // IRgen to use LLVM intrinsics for such functions. 3088 if (!getLangOptions().MathErrno && 3089 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3090 if (!FD->getAttr<ConstAttr>()) 3091 FD->addAttr(::new (Context) ConstAttr()); 3092 } 3093 } 3094 3095 IdentifierInfo *Name = FD->getIdentifier(); 3096 if (!Name) 3097 return; 3098 if ((!getLangOptions().CPlusPlus && 3099 FD->getDeclContext()->isTranslationUnit()) || 3100 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3101 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3102 LinkageSpecDecl::lang_c)) { 3103 // Okay: this could be a libc/libm/Objective-C function we know 3104 // about. 3105 } else 3106 return; 3107 3108 unsigned KnownID; 3109 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3110 if (KnownFunctionIDs[KnownID] == Name) 3111 break; 3112 3113 switch (KnownID) { 3114 case id_NSLog: 3115 case id_NSLogv: 3116 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3117 // FIXME: We known better than our headers. 3118 const_cast<FormatAttr *>(Format)->setType("printf"); 3119 } else 3120 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3121 break; 3122 3123 case id_asprintf: 3124 case id_vasprintf: 3125 if (!FD->getAttr<FormatAttr>()) 3126 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3127 break; 3128 3129 default: 3130 // Unknown function or known function without any attributes to 3131 // add. Do nothing. 3132 break; 3133 } 3134} 3135 3136TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3137 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3138 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3139 3140 // Scope manipulation handled by caller. 3141 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3142 D.getIdentifierLoc(), 3143 D.getIdentifier(), 3144 T); 3145 3146 if (TagType *TT = dyn_cast<TagType>(T)) { 3147 TagDecl *TD = TT->getDecl(); 3148 3149 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3150 // keep track of the TypedefDecl. 3151 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3152 TD->setTypedefForAnonDecl(NewTD); 3153 } 3154 3155 if (D.getInvalidType()) 3156 NewTD->setInvalidDecl(); 3157 return NewTD; 3158} 3159 3160/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3161/// former case, Name will be non-null. In the later case, Name will be null. 3162/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3163/// reference/declaration/definition of a tag. 3164Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3165 SourceLocation KWLoc, const CXXScopeSpec &SS, 3166 IdentifierInfo *Name, SourceLocation NameLoc, 3167 AttributeList *Attr, AccessSpecifier AS) { 3168 // If this is not a definition, it must have a name. 3169 assert((Name != 0 || TK == TK_Definition) && 3170 "Nameless record must be a definition!"); 3171 3172 TagDecl::TagKind Kind; 3173 switch (TagSpec) { 3174 default: assert(0 && "Unknown tag type!"); 3175 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3176 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3177 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3178 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3179 } 3180 3181 DeclContext *SearchDC = CurContext; 3182 DeclContext *DC = CurContext; 3183 NamedDecl *PrevDecl = 0; 3184 3185 bool Invalid = false; 3186 3187 if (Name && SS.isNotEmpty()) { 3188 // We have a nested-name tag ('struct foo::bar'). 3189 3190 // Check for invalid 'foo::'. 3191 if (SS.isInvalid()) { 3192 Name = 0; 3193 goto CreateNewDecl; 3194 } 3195 3196 // FIXME: RequireCompleteDeclContext(SS)? 3197 DC = computeDeclContext(SS); 3198 SearchDC = DC; 3199 // Look-up name inside 'foo::'. 3200 PrevDecl = dyn_cast_or_null<TagDecl>( 3201 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3202 3203 // A tag 'foo::bar' must already exist. 3204 if (PrevDecl == 0) { 3205 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3206 Name = 0; 3207 goto CreateNewDecl; 3208 } 3209 } else if (Name) { 3210 // If this is a named struct, check to see if there was a previous forward 3211 // declaration or definition. 3212 // FIXME: We're looking into outer scopes here, even when we 3213 // shouldn't be. Doing so can result in ambiguities that we 3214 // shouldn't be diagnosing. 3215 LookupResult R = LookupName(S, Name, LookupTagName, 3216 /*RedeclarationOnly=*/(TK != TK_Reference)); 3217 if (R.isAmbiguous()) { 3218 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3219 // FIXME: This is not best way to recover from case like: 3220 // 3221 // struct S s; 3222 // 3223 // causes needless "incomplete type" error later. 3224 Name = 0; 3225 PrevDecl = 0; 3226 Invalid = true; 3227 } 3228 else 3229 PrevDecl = R; 3230 3231 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3232 // FIXME: This makes sure that we ignore the contexts associated 3233 // with C structs, unions, and enums when looking for a matching 3234 // tag declaration or definition. See the similar lookup tweak 3235 // in Sema::LookupName; is there a better way to deal with this? 3236 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3237 SearchDC = SearchDC->getParent(); 3238 } 3239 } 3240 3241 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3242 // Maybe we will complain about the shadowed template parameter. 3243 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3244 // Just pretend that we didn't see the previous declaration. 3245 PrevDecl = 0; 3246 } 3247 3248 if (PrevDecl) { 3249 // Check whether the previous declaration is usable. 3250 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3251 3252 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3253 // If this is a use of a previous tag, or if the tag is already declared 3254 // in the same scope (so that the definition/declaration completes or 3255 // rementions the tag), reuse the decl. 3256 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3257 // Make sure that this wasn't declared as an enum and now used as a 3258 // struct or something similar. 3259 if (PrevTagDecl->getTagKind() != Kind) { 3260 bool SafeToContinue 3261 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3262 Kind != TagDecl::TK_enum); 3263 if (SafeToContinue) 3264 Diag(KWLoc, diag::err_use_with_wrong_tag) 3265 << Name 3266 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3267 PrevTagDecl->getKindName()); 3268 else 3269 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3270 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3271 3272 if (SafeToContinue) 3273 Kind = PrevTagDecl->getTagKind(); 3274 else { 3275 // Recover by making this an anonymous redefinition. 3276 Name = 0; 3277 PrevDecl = 0; 3278 Invalid = true; 3279 } 3280 } 3281 3282 if (!Invalid) { 3283 // If this is a use, just return the declaration we found. 3284 3285 // FIXME: In the future, return a variant or some other clue 3286 // for the consumer of this Decl to know it doesn't own it. 3287 // For our current ASTs this shouldn't be a problem, but will 3288 // need to be changed with DeclGroups. 3289 if (TK == TK_Reference) 3290 return DeclPtrTy::make(PrevDecl); 3291 3292 // Diagnose attempts to redefine a tag. 3293 if (TK == TK_Definition) { 3294 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3295 Diag(NameLoc, diag::err_redefinition) << Name; 3296 Diag(Def->getLocation(), diag::note_previous_definition); 3297 // If this is a redefinition, recover by making this 3298 // struct be anonymous, which will make any later 3299 // references get the previous definition. 3300 Name = 0; 3301 PrevDecl = 0; 3302 Invalid = true; 3303 } else { 3304 // If the type is currently being defined, complain 3305 // about a nested redefinition. 3306 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3307 if (Tag->isBeingDefined()) { 3308 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3309 Diag(PrevTagDecl->getLocation(), 3310 diag::note_previous_definition); 3311 Name = 0; 3312 PrevDecl = 0; 3313 Invalid = true; 3314 } 3315 } 3316 3317 // Okay, this is definition of a previously declared or referenced 3318 // tag PrevDecl. We're going to create a new Decl for it. 3319 } 3320 } 3321 // If we get here we have (another) forward declaration or we 3322 // have a definition. Just create a new decl. 3323 } else { 3324 // If we get here, this is a definition of a new tag type in a nested 3325 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3326 // new decl/type. We set PrevDecl to NULL so that the entities 3327 // have distinct types. 3328 PrevDecl = 0; 3329 } 3330 // If we get here, we're going to create a new Decl. If PrevDecl 3331 // is non-NULL, it's a definition of the tag declared by 3332 // PrevDecl. If it's NULL, we have a new definition. 3333 } else { 3334 // PrevDecl is a namespace, template, or anything else 3335 // that lives in the IDNS_Tag identifier namespace. 3336 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3337 // The tag name clashes with a namespace name, issue an error and 3338 // recover by making this tag be anonymous. 3339 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3340 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3341 Name = 0; 3342 PrevDecl = 0; 3343 Invalid = true; 3344 } else { 3345 // The existing declaration isn't relevant to us; we're in a 3346 // new scope, so clear out the previous declaration. 3347 PrevDecl = 0; 3348 } 3349 } 3350 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3351 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3352 // C.scope.pdecl]p5: 3353 // -- for an elaborated-type-specifier of the form 3354 // 3355 // class-key identifier 3356 // 3357 // if the elaborated-type-specifier is used in the 3358 // decl-specifier-seq or parameter-declaration-clause of a 3359 // function defined in namespace scope, the identifier is 3360 // declared as a class-name in the namespace that contains 3361 // the declaration; otherwise, except as a friend 3362 // declaration, the identifier is declared in the smallest 3363 // non-class, non-function-prototype scope that contains the 3364 // declaration. 3365 // 3366 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3367 // C structs and unions. 3368 // 3369 // GNU C also supports this behavior as part of its incomplete 3370 // enum types extension, while GNU C++ does not. 3371 // 3372 // Find the context where we'll be declaring the tag. 3373 // FIXME: We would like to maintain the current DeclContext as the 3374 // lexical context, 3375 while (SearchDC->isRecord()) 3376 SearchDC = SearchDC->getParent(); 3377 3378 // Find the scope where we'll be declaring the tag. 3379 while (S->isClassScope() || 3380 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3381 ((S->getFlags() & Scope::DeclScope) == 0) || 3382 (S->getEntity() && 3383 ((DeclContext *)S->getEntity())->isTransparentContext())) 3384 S = S->getParent(); 3385 } 3386 3387CreateNewDecl: 3388 3389 // If there is an identifier, use the location of the identifier as the 3390 // location of the decl, otherwise use the location of the struct/union 3391 // keyword. 3392 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3393 3394 // Otherwise, create a new declaration. If there is a previous 3395 // declaration of the same entity, the two will be linked via 3396 // PrevDecl. 3397 TagDecl *New; 3398 3399 if (Kind == TagDecl::TK_enum) { 3400 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3401 // enum X { A, B, C } D; D should chain to X. 3402 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3403 cast_or_null<EnumDecl>(PrevDecl)); 3404 // If this is an undefined enum, warn. 3405 if (TK != TK_Definition && !Invalid) { 3406 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3407 : diag::ext_forward_ref_enum; 3408 Diag(Loc, DK); 3409 } 3410 } else { 3411 // struct/union/class 3412 3413 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3414 // struct X { int A; } D; D should chain to X. 3415 if (getLangOptions().CPlusPlus) 3416 // FIXME: Look for a way to use RecordDecl for simple structs. 3417 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3418 cast_or_null<CXXRecordDecl>(PrevDecl)); 3419 else 3420 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3421 cast_or_null<RecordDecl>(PrevDecl)); 3422 } 3423 3424 if (Kind != TagDecl::TK_enum) { 3425 // Handle #pragma pack: if the #pragma pack stack has non-default 3426 // alignment, make up a packed attribute for this decl. These 3427 // attributes are checked when the ASTContext lays out the 3428 // structure. 3429 // 3430 // It is important for implementing the correct semantics that this 3431 // happen here (in act on tag decl). The #pragma pack stack is 3432 // maintained as a result of parser callbacks which can occur at 3433 // many points during the parsing of a struct declaration (because 3434 // the #pragma tokens are effectively skipped over during the 3435 // parsing of the struct). 3436 if (unsigned Alignment = getPragmaPackAlignment()) 3437 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3438 } 3439 3440 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3441 // C++ [dcl.typedef]p3: 3442 // [...] Similarly, in a given scope, a class or enumeration 3443 // shall not be declared with the same name as a typedef-name 3444 // that is declared in that scope and refers to a type other 3445 // than the class or enumeration itself. 3446 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3447 TypedefDecl *PrevTypedef = 0; 3448 if (Lookup.getKind() == LookupResult::Found) 3449 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3450 3451 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3452 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3453 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3454 Diag(Loc, diag::err_tag_definition_of_typedef) 3455 << Context.getTypeDeclType(New) 3456 << PrevTypedef->getUnderlyingType(); 3457 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3458 Invalid = true; 3459 } 3460 } 3461 3462 if (Invalid) 3463 New->setInvalidDecl(); 3464 3465 if (Attr) 3466 ProcessDeclAttributeList(New, Attr); 3467 3468 // If we're declaring or defining a tag in function prototype scope 3469 // in C, note that this type can only be used within the function. 3470 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3471 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3472 3473 // Set the lexical context. If the tag has a C++ scope specifier, the 3474 // lexical context will be different from the semantic context. 3475 New->setLexicalDeclContext(CurContext); 3476 3477 // Set the access specifier. 3478 SetMemberAccessSpecifier(New, PrevDecl, AS); 3479 3480 if (TK == TK_Definition) 3481 New->startDefinition(); 3482 3483 // If this has an identifier, add it to the scope stack. 3484 if (Name) { 3485 S = getNonFieldDeclScope(S); 3486 PushOnScopeChains(New, S); 3487 } else { 3488 CurContext->addDecl(Context, New); 3489 } 3490 3491 return DeclPtrTy::make(New); 3492} 3493 3494void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3495 AdjustDeclIfTemplate(TagD); 3496 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3497 3498 // Enter the tag context. 3499 PushDeclContext(S, Tag); 3500 3501 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3502 FieldCollector->StartClass(); 3503 3504 if (Record->getIdentifier()) { 3505 // C++ [class]p2: 3506 // [...] The class-name is also inserted into the scope of the 3507 // class itself; this is known as the injected-class-name. For 3508 // purposes of access checking, the injected-class-name is treated 3509 // as if it were a public member name. 3510 CXXRecordDecl *InjectedClassName 3511 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3512 CurContext, Record->getLocation(), 3513 Record->getIdentifier(), Record); 3514 InjectedClassName->setImplicit(); 3515 InjectedClassName->setAccess(AS_public); 3516 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3517 InjectedClassName->setDescribedClassTemplate(Template); 3518 PushOnScopeChains(InjectedClassName, S); 3519 assert(InjectedClassName->isInjectedClassName() && 3520 "Broken injected-class-name"); 3521 } 3522 } 3523} 3524 3525void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3526 AdjustDeclIfTemplate(TagD); 3527 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3528 3529 if (isa<CXXRecordDecl>(Tag)) 3530 FieldCollector->FinishClass(); 3531 3532 // Exit this scope of this tag's definition. 3533 PopDeclContext(); 3534 3535 // Notify the consumer that we've defined a tag. 3536 Consumer.HandleTagDeclDefinition(Tag); 3537} 3538 3539bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3540 QualType FieldTy, const Expr *BitWidth) { 3541 // C99 6.7.2.1p4 - verify the field type. 3542 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3543 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3544 // Handle incomplete types with specific error. 3545 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3546 return true; 3547 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3548 << FieldName << FieldTy << BitWidth->getSourceRange(); 3549 } 3550 3551 // If the bit-width is type- or value-dependent, don't try to check 3552 // it now. 3553 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3554 return false; 3555 3556 llvm::APSInt Value; 3557 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3558 return true; 3559 3560 // Zero-width bitfield is ok for anonymous field. 3561 if (Value == 0 && FieldName) 3562 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3563 3564 if (Value.isSigned() && Value.isNegative()) 3565 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3566 << FieldName << Value.toString(10); 3567 3568 if (!FieldTy->isDependentType()) { 3569 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3570 // FIXME: We won't need the 0 size once we check that the field type is valid. 3571 if (TypeSize && Value.getZExtValue() > TypeSize) 3572 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3573 << FieldName << (unsigned)TypeSize; 3574 } 3575 3576 return false; 3577} 3578 3579/// ActOnField - Each field of a struct/union/class is passed into this in order 3580/// to create a FieldDecl object for it. 3581Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3582 SourceLocation DeclStart, 3583 Declarator &D, ExprTy *BitfieldWidth) { 3584 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3585 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3586 AS_public); 3587 return DeclPtrTy::make(Res); 3588} 3589 3590/// HandleField - Analyze a field of a C struct or a C++ data member. 3591/// 3592FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3593 SourceLocation DeclStart, 3594 Declarator &D, Expr *BitWidth, 3595 AccessSpecifier AS) { 3596 IdentifierInfo *II = D.getIdentifier(); 3597 SourceLocation Loc = DeclStart; 3598 if (II) Loc = D.getIdentifierLoc(); 3599 3600 QualType T = GetTypeForDeclarator(D, S); 3601 3602 if (getLangOptions().CPlusPlus) { 3603 CheckExtraCXXDefaultArguments(D); 3604 } 3605 3606 DiagnoseFunctionSpecifiers(D); 3607 3608 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3609 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3610 PrevDecl = 0; 3611 3612 FieldDecl *NewFD 3613 = CheckFieldDecl(II, T, Record, Loc, 3614 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3615 BitWidth, AS, PrevDecl, &D); 3616 if (NewFD->isInvalidDecl() && PrevDecl) { 3617 // Don't introduce NewFD into scope; there's already something 3618 // with the same name in the same scope. 3619 } else if (II) { 3620 PushOnScopeChains(NewFD, S); 3621 } else 3622 Record->addDecl(Context, NewFD); 3623 3624 return NewFD; 3625} 3626 3627/// \brief Build a new FieldDecl and check its well-formedness. 3628/// 3629/// This routine builds a new FieldDecl given the fields name, type, 3630/// record, etc. \p PrevDecl should refer to any previous declaration 3631/// with the same name and in the same scope as the field to be 3632/// created. 3633/// 3634/// \returns a new FieldDecl. 3635/// 3636/// \todo The Declarator argument is a hack. It will be removed once 3637FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3638 RecordDecl *Record, SourceLocation Loc, 3639 bool Mutable, Expr *BitWidth, 3640 AccessSpecifier AS, NamedDecl *PrevDecl, 3641 Declarator *D) { 3642 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3643 bool InvalidDecl = false; 3644 3645 // If we receive a broken type, recover by assuming 'int' and 3646 // marking this declaration as invalid. 3647 if (T.isNull()) { 3648 InvalidDecl = true; 3649 T = Context.IntTy; 3650 } 3651 3652 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3653 // than a variably modified type. 3654 if (T->isVariablyModifiedType()) { 3655 bool SizeIsNegative; 3656 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3657 SizeIsNegative); 3658 if (!FixedTy.isNull()) { 3659 Diag(Loc, diag::warn_illegal_constant_array_size); 3660 T = FixedTy; 3661 } else { 3662 if (SizeIsNegative) 3663 Diag(Loc, diag::err_typecheck_negative_array_size); 3664 else 3665 Diag(Loc, diag::err_typecheck_field_variable_size); 3666 T = Context.IntTy; 3667 InvalidDecl = true; 3668 } 3669 } 3670 3671 // Fields can not have abstract class types 3672 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3673 AbstractFieldType)) 3674 InvalidDecl = true; 3675 3676 // If this is declared as a bit-field, check the bit-field. 3677 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3678 InvalidDecl = true; 3679 DeleteExpr(BitWidth); 3680 BitWidth = 0; 3681 } 3682 3683 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3684 Mutable); 3685 3686 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3687 Diag(Loc, diag::err_duplicate_member) << II; 3688 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3689 NewFD->setInvalidDecl(); 3690 Record->setInvalidDecl(); 3691 } 3692 3693 if (getLangOptions().CPlusPlus && !T->isPODType()) 3694 cast<CXXRecordDecl>(Record)->setPOD(false); 3695 3696 // FIXME: We need to pass in the attributes given an AST 3697 // representation, not a parser representation. 3698 if (D) 3699 ProcessDeclAttributes(NewFD, *D); 3700 3701 if (T.isObjCGCWeak()) 3702 Diag(Loc, diag::warn_attribute_weak_on_field); 3703 3704 if (InvalidDecl) 3705 NewFD->setInvalidDecl(); 3706 3707 NewFD->setAccess(AS); 3708 3709 // C++ [dcl.init.aggr]p1: 3710 // An aggregate is an array or a class (clause 9) with [...] no 3711 // private or protected non-static data members (clause 11). 3712 // A POD must be an aggregate. 3713 if (getLangOptions().CPlusPlus && 3714 (AS == AS_private || AS == AS_protected)) { 3715 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3716 CXXRecord->setAggregate(false); 3717 CXXRecord->setPOD(false); 3718 } 3719 3720 return NewFD; 3721} 3722 3723/// TranslateIvarVisibility - Translate visibility from a token ID to an 3724/// AST enum value. 3725static ObjCIvarDecl::AccessControl 3726TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3727 switch (ivarVisibility) { 3728 default: assert(0 && "Unknown visitibility kind"); 3729 case tok::objc_private: return ObjCIvarDecl::Private; 3730 case tok::objc_public: return ObjCIvarDecl::Public; 3731 case tok::objc_protected: return ObjCIvarDecl::Protected; 3732 case tok::objc_package: return ObjCIvarDecl::Package; 3733 } 3734} 3735 3736/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3737/// in order to create an IvarDecl object for it. 3738Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3739 SourceLocation DeclStart, 3740 Declarator &D, ExprTy *BitfieldWidth, 3741 tok::ObjCKeywordKind Visibility) { 3742 3743 IdentifierInfo *II = D.getIdentifier(); 3744 Expr *BitWidth = (Expr*)BitfieldWidth; 3745 SourceLocation Loc = DeclStart; 3746 if (II) Loc = D.getIdentifierLoc(); 3747 3748 // FIXME: Unnamed fields can be handled in various different ways, for 3749 // example, unnamed unions inject all members into the struct namespace! 3750 3751 QualType T = GetTypeForDeclarator(D, S); 3752 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3753 bool InvalidDecl = false; 3754 3755 if (BitWidth) { 3756 // 6.7.2.1p3, 6.7.2.1p4 3757 if (VerifyBitField(Loc, II, T, BitWidth)) { 3758 InvalidDecl = true; 3759 DeleteExpr(BitWidth); 3760 BitWidth = 0; 3761 } 3762 } else { 3763 // Not a bitfield. 3764 3765 // validate II. 3766 3767 } 3768 3769 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3770 // than a variably modified type. 3771 if (T->isVariablyModifiedType()) { 3772 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3773 InvalidDecl = true; 3774 } 3775 3776 // Get the visibility (access control) for this ivar. 3777 ObjCIvarDecl::AccessControl ac = 3778 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3779 : ObjCIvarDecl::None; 3780 3781 // Construct the decl. 3782 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3783 (Expr *)BitfieldWidth); 3784 3785 if (II) { 3786 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3787 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3788 && !isa<TagDecl>(PrevDecl)) { 3789 Diag(Loc, diag::err_duplicate_member) << II; 3790 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3791 NewID->setInvalidDecl(); 3792 } 3793 } 3794 3795 // Process attributes attached to the ivar. 3796 ProcessDeclAttributes(NewID, D); 3797 3798 if (D.getInvalidType() || InvalidDecl) 3799 NewID->setInvalidDecl(); 3800 3801 if (II) { 3802 // FIXME: When interfaces are DeclContexts, we'll need to add 3803 // these to the interface. 3804 S->AddDecl(DeclPtrTy::make(NewID)); 3805 IdResolver.AddDecl(NewID); 3806 } 3807 3808 return DeclPtrTy::make(NewID); 3809} 3810 3811void Sema::ActOnFields(Scope* S, 3812 SourceLocation RecLoc, DeclPtrTy RecDecl, 3813 DeclPtrTy *Fields, unsigned NumFields, 3814 SourceLocation LBrac, SourceLocation RBrac, 3815 AttributeList *Attr) { 3816 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3817 assert(EnclosingDecl && "missing record or interface decl"); 3818 3819 // If the decl this is being inserted into is invalid, then it may be a 3820 // redeclaration or some other bogus case. Don't try to add fields to it. 3821 if (EnclosingDecl->isInvalidDecl()) { 3822 // FIXME: Deallocate fields? 3823 return; 3824 } 3825 3826 3827 // Verify that all the fields are okay. 3828 unsigned NumNamedMembers = 0; 3829 llvm::SmallVector<FieldDecl*, 32> RecFields; 3830 3831 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3832 for (unsigned i = 0; i != NumFields; ++i) { 3833 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3834 3835 // Get the type for the field. 3836 Type *FDTy = FD->getType().getTypePtr(); 3837 3838 if (!FD->isAnonymousStructOrUnion()) { 3839 // Remember all fields written by the user. 3840 RecFields.push_back(FD); 3841 } 3842 3843 // If the field is already invalid for some reason, don't emit more 3844 // diagnostics about it. 3845 if (FD->isInvalidDecl()) 3846 continue; 3847 3848 // C99 6.7.2.1p2: 3849 // A structure or union shall not contain a member with 3850 // incomplete or function type (hence, a structure shall not 3851 // contain an instance of itself, but may contain a pointer to 3852 // an instance of itself), except that the last member of a 3853 // structure with more than one named member may have incomplete 3854 // array type; such a structure (and any union containing, 3855 // possibly recursively, a member that is such a structure) 3856 // shall not be a member of a structure or an element of an 3857 // array. 3858 if (FDTy->isFunctionType()) { 3859 // Field declared as a function. 3860 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3861 << FD->getDeclName(); 3862 FD->setInvalidDecl(); 3863 EnclosingDecl->setInvalidDecl(); 3864 continue; 3865 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3866 Record && Record->isStruct()) { 3867 // Flexible array member. 3868 if (NumNamedMembers < 1) { 3869 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3870 << FD->getDeclName(); 3871 FD->setInvalidDecl(); 3872 EnclosingDecl->setInvalidDecl(); 3873 continue; 3874 } 3875 // Okay, we have a legal flexible array member at the end of the struct. 3876 if (Record) 3877 Record->setHasFlexibleArrayMember(true); 3878 } else if (!FDTy->isDependentType() && 3879 RequireCompleteType(FD->getLocation(), FD->getType(), 3880 diag::err_field_incomplete)) { 3881 // Incomplete type 3882 FD->setInvalidDecl(); 3883 EnclosingDecl->setInvalidDecl(); 3884 continue; 3885 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3886 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3887 // If this is a member of a union, then entire union becomes "flexible". 3888 if (Record && Record->isUnion()) { 3889 Record->setHasFlexibleArrayMember(true); 3890 } else { 3891 // If this is a struct/class and this is not the last element, reject 3892 // it. Note that GCC supports variable sized arrays in the middle of 3893 // structures. 3894 if (i != NumFields-1) 3895 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3896 << FD->getDeclName(); 3897 else { 3898 // We support flexible arrays at the end of structs in 3899 // other structs as an extension. 3900 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3901 << FD->getDeclName(); 3902 if (Record) 3903 Record->setHasFlexibleArrayMember(true); 3904 } 3905 } 3906 } 3907 } else if (FDTy->isObjCInterfaceType()) { 3908 /// A field cannot be an Objective-c object 3909 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3910 FD->setInvalidDecl(); 3911 EnclosingDecl->setInvalidDecl(); 3912 continue; 3913 } 3914 // Keep track of the number of named members. 3915 if (FD->getIdentifier()) 3916 ++NumNamedMembers; 3917 } 3918 3919 // Okay, we successfully defined 'Record'. 3920 if (Record) { 3921 Record->completeDefinition(Context); 3922 } else { 3923 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3924 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3925 ID->setIVarList(ClsFields, RecFields.size(), Context); 3926 ID->setLocEnd(RBrac); 3927 3928 // Must enforce the rule that ivars in the base classes may not be 3929 // duplicates. 3930 if (ID->getSuperClass()) { 3931 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3932 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3933 ObjCIvarDecl* Ivar = (*IVI); 3934 IdentifierInfo *II = Ivar->getIdentifier(); 3935 ObjCIvarDecl* prevIvar = 3936 ID->getSuperClass()->lookupInstanceVariable(Context, II); 3937 if (prevIvar) { 3938 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3939 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3940 } 3941 } 3942 } 3943 } else if (ObjCImplementationDecl *IMPDecl = 3944 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3945 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3946 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3947 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3948 } 3949 } 3950 3951 if (Attr) 3952 ProcessDeclAttributeList(Record, Attr); 3953} 3954 3955EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 3956 EnumConstantDecl *LastEnumConst, 3957 SourceLocation IdLoc, 3958 IdentifierInfo *Id, 3959 ExprArg val) { 3960 Expr *Val = (Expr *)val.get(); 3961 3962 llvm::APSInt EnumVal(32); 3963 QualType EltTy; 3964 if (Val && !Val->isTypeDependent()) { 3965 // Make sure to promote the operand type to int. 3966 UsualUnaryConversions(Val); 3967 if (Val != val.get()) { 3968 val.release(); 3969 val = Val; 3970 } 3971 3972 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3973 SourceLocation ExpLoc; 3974 if (!Val->isValueDependent() && 3975 VerifyIntegerConstantExpression(Val, &EnumVal)) { 3976 Val = 0; 3977 } else { 3978 EltTy = Val->getType(); 3979 } 3980 } 3981 3982 if (!Val) { 3983 if (LastEnumConst) { 3984 // Assign the last value + 1. 3985 EnumVal = LastEnumConst->getInitVal(); 3986 ++EnumVal; 3987 3988 // Check for overflow on increment. 3989 if (EnumVal < LastEnumConst->getInitVal()) 3990 Diag(IdLoc, diag::warn_enum_value_overflow); 3991 3992 EltTy = LastEnumConst->getType(); 3993 } else { 3994 // First value, set to zero. 3995 EltTy = Context.IntTy; 3996 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3997 } 3998 } 3999 4000 val.release(); 4001 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4002 Val, EnumVal); 4003} 4004 4005 4006Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4007 DeclPtrTy lastEnumConst, 4008 SourceLocation IdLoc, 4009 IdentifierInfo *Id, 4010 SourceLocation EqualLoc, ExprTy *val) { 4011 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4012 EnumConstantDecl *LastEnumConst = 4013 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4014 Expr *Val = static_cast<Expr*>(val); 4015 4016 // The scope passed in may not be a decl scope. Zip up the scope tree until 4017 // we find one that is. 4018 S = getNonFieldDeclScope(S); 4019 4020 // Verify that there isn't already something declared with this name in this 4021 // scope. 4022 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4023 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4024 // Maybe we will complain about the shadowed template parameter. 4025 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4026 // Just pretend that we didn't see the previous declaration. 4027 PrevDecl = 0; 4028 } 4029 4030 if (PrevDecl) { 4031 // When in C++, we may get a TagDecl with the same name; in this case the 4032 // enum constant will 'hide' the tag. 4033 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4034 "Received TagDecl when not in C++!"); 4035 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4036 if (isa<EnumConstantDecl>(PrevDecl)) 4037 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4038 else 4039 Diag(IdLoc, diag::err_redefinition) << Id; 4040 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4041 if (Val) Val->Destroy(Context); 4042 return DeclPtrTy(); 4043 } 4044 } 4045 4046 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4047 IdLoc, Id, Owned(Val)); 4048 4049 // Register this decl in the current scope stack. 4050 if (New) 4051 PushOnScopeChains(New, S); 4052 4053 return DeclPtrTy::make(New); 4054} 4055 4056// FIXME: For consistency with ActOnFields(), we should have the parser 4057// pass in the source location for the left/right braces. 4058void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4059 DeclPtrTy *Elements, unsigned NumElements) { 4060 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4061 QualType EnumType = Context.getTypeDeclType(Enum); 4062 4063 // TODO: If the result value doesn't fit in an int, it must be a long or long 4064 // long value. ISO C does not support this, but GCC does as an extension, 4065 // emit a warning. 4066 unsigned IntWidth = Context.Target.getIntWidth(); 4067 4068 // Verify that all the values are okay, compute the size of the values, and 4069 // reverse the list. 4070 unsigned NumNegativeBits = 0; 4071 unsigned NumPositiveBits = 0; 4072 4073 // Keep track of whether all elements have type int. 4074 bool AllElementsInt = true; 4075 4076 for (unsigned i = 0; i != NumElements; ++i) { 4077 EnumConstantDecl *ECD = 4078 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4079 if (!ECD) continue; // Already issued a diagnostic. 4080 4081 // If the enum value doesn't fit in an int, emit an extension warning. 4082 const llvm::APSInt &InitVal = ECD->getInitVal(); 4083 assert(InitVal.getBitWidth() >= IntWidth && 4084 "Should have promoted value to int"); 4085 if (InitVal.getBitWidth() > IntWidth) { 4086 llvm::APSInt V(InitVal); 4087 V.trunc(IntWidth); 4088 V.extend(InitVal.getBitWidth()); 4089 if (V != InitVal) 4090 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4091 << InitVal.toString(10); 4092 } 4093 4094 // Keep track of the size of positive and negative values. 4095 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4096 NumPositiveBits = std::max(NumPositiveBits, 4097 (unsigned)InitVal.getActiveBits()); 4098 else 4099 NumNegativeBits = std::max(NumNegativeBits, 4100 (unsigned)InitVal.getMinSignedBits()); 4101 4102 // Keep track of whether every enum element has type int (very commmon). 4103 if (AllElementsInt) 4104 AllElementsInt = ECD->getType() == Context.IntTy; 4105 } 4106 4107 // Figure out the type that should be used for this enum. 4108 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4109 QualType BestType; 4110 unsigned BestWidth; 4111 4112 if (NumNegativeBits) { 4113 // If there is a negative value, figure out the smallest integer type (of 4114 // int/long/longlong) that fits. 4115 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4116 BestType = Context.IntTy; 4117 BestWidth = IntWidth; 4118 } else { 4119 BestWidth = Context.Target.getLongWidth(); 4120 4121 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4122 BestType = Context.LongTy; 4123 else { 4124 BestWidth = Context.Target.getLongLongWidth(); 4125 4126 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4127 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4128 BestType = Context.LongLongTy; 4129 } 4130 } 4131 } else { 4132 // If there is no negative value, figure out which of uint, ulong, ulonglong 4133 // fits. 4134 if (NumPositiveBits <= IntWidth) { 4135 BestType = Context.UnsignedIntTy; 4136 BestWidth = IntWidth; 4137 } else if (NumPositiveBits <= 4138 (BestWidth = Context.Target.getLongWidth())) { 4139 BestType = Context.UnsignedLongTy; 4140 } else { 4141 BestWidth = Context.Target.getLongLongWidth(); 4142 assert(NumPositiveBits <= BestWidth && 4143 "How could an initializer get larger than ULL?"); 4144 BestType = Context.UnsignedLongLongTy; 4145 } 4146 } 4147 4148 // Loop over all of the enumerator constants, changing their types to match 4149 // the type of the enum if needed. 4150 for (unsigned i = 0; i != NumElements; ++i) { 4151 EnumConstantDecl *ECD = 4152 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4153 if (!ECD) continue; // Already issued a diagnostic. 4154 4155 // Standard C says the enumerators have int type, but we allow, as an 4156 // extension, the enumerators to be larger than int size. If each 4157 // enumerator value fits in an int, type it as an int, otherwise type it the 4158 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4159 // that X has type 'int', not 'unsigned'. 4160 if (ECD->getType() == Context.IntTy) { 4161 // Make sure the init value is signed. 4162 llvm::APSInt IV = ECD->getInitVal(); 4163 IV.setIsSigned(true); 4164 ECD->setInitVal(IV); 4165 4166 if (getLangOptions().CPlusPlus) 4167 // C++ [dcl.enum]p4: Following the closing brace of an 4168 // enum-specifier, each enumerator has the type of its 4169 // enumeration. 4170 ECD->setType(EnumType); 4171 continue; // Already int type. 4172 } 4173 4174 // Determine whether the value fits into an int. 4175 llvm::APSInt InitVal = ECD->getInitVal(); 4176 bool FitsInInt; 4177 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4178 FitsInInt = InitVal.getActiveBits() < IntWidth; 4179 else 4180 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4181 4182 // If it fits into an integer type, force it. Otherwise force it to match 4183 // the enum decl type. 4184 QualType NewTy; 4185 unsigned NewWidth; 4186 bool NewSign; 4187 if (FitsInInt) { 4188 NewTy = Context.IntTy; 4189 NewWidth = IntWidth; 4190 NewSign = true; 4191 } else if (ECD->getType() == BestType) { 4192 // Already the right type! 4193 if (getLangOptions().CPlusPlus) 4194 // C++ [dcl.enum]p4: Following the closing brace of an 4195 // enum-specifier, each enumerator has the type of its 4196 // enumeration. 4197 ECD->setType(EnumType); 4198 continue; 4199 } else { 4200 NewTy = BestType; 4201 NewWidth = BestWidth; 4202 NewSign = BestType->isSignedIntegerType(); 4203 } 4204 4205 // Adjust the APSInt value. 4206 InitVal.extOrTrunc(NewWidth); 4207 InitVal.setIsSigned(NewSign); 4208 ECD->setInitVal(InitVal); 4209 4210 // Adjust the Expr initializer and type. 4211 if (ECD->getInitExpr()) 4212 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4213 /*isLvalue=*/false)); 4214 if (getLangOptions().CPlusPlus) 4215 // C++ [dcl.enum]p4: Following the closing brace of an 4216 // enum-specifier, each enumerator has the type of its 4217 // enumeration. 4218 ECD->setType(EnumType); 4219 else 4220 ECD->setType(NewTy); 4221 } 4222 4223 Enum->completeDefinition(Context, BestType); 4224} 4225 4226Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4227 ExprArg expr) { 4228 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4229 4230 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4231 Loc, AsmString)); 4232} 4233 4234