SemaDecl.cpp revision c55b0b035289cd7702034bad930c71302bc80836
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 bool isVirtualOkay = false; 1897 FunctionDecl *NewFD; 1898 if (D.getKind() == Declarator::DK_Constructor) { 1899 // This is a C++ constructor declaration. 1900 assert(DC->isRecord() && 1901 "Constructors can only be declared in a member context"); 1902 1903 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1904 1905 // Create the new declaration 1906 NewFD = CXXConstructorDecl::Create(Context, 1907 cast<CXXRecordDecl>(DC), 1908 D.getIdentifierLoc(), Name, R, 1909 isExplicit, isInline, 1910 /*isImplicitlyDeclared=*/false); 1911 1912 if (InvalidDecl) 1913 NewFD->setInvalidDecl(); 1914 } else if (D.getKind() == Declarator::DK_Destructor) { 1915 // This is a C++ destructor declaration. 1916 if (DC->isRecord()) { 1917 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1918 1919 NewFD = CXXDestructorDecl::Create(Context, 1920 cast<CXXRecordDecl>(DC), 1921 D.getIdentifierLoc(), Name, R, 1922 isInline, 1923 /*isImplicitlyDeclared=*/false); 1924 1925 if (InvalidDecl) 1926 NewFD->setInvalidDecl(); 1927 1928 isVirtualOkay = true; 1929 } else { 1930 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1931 1932 // Create a FunctionDecl to satisfy the function definition parsing 1933 // code path. 1934 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1935 Name, R, SC, isInline, 1936 /*hasPrototype=*/true, 1937 // FIXME: Move to DeclGroup... 1938 D.getDeclSpec().getSourceRange().getBegin()); 1939 InvalidDecl = true; 1940 NewFD->setInvalidDecl(); 1941 } 1942 } else if (D.getKind() == Declarator::DK_Conversion) { 1943 if (!DC->isRecord()) { 1944 Diag(D.getIdentifierLoc(), 1945 diag::err_conv_function_not_member); 1946 return 0; 1947 } else { 1948 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1949 1950 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1951 D.getIdentifierLoc(), Name, R, 1952 isInline, isExplicit); 1953 1954 if (InvalidDecl) 1955 NewFD->setInvalidDecl(); 1956 1957 isVirtualOkay = true; 1958 } 1959 } else if (DC->isRecord()) { 1960 // This is a C++ method declaration. 1961 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1962 D.getIdentifierLoc(), Name, R, 1963 (SC == FunctionDecl::Static), isInline); 1964 1965 isVirtualOkay = (SC != FunctionDecl::Static); 1966 } else { 1967 // Determine whether the function was written with a 1968 // prototype. This true when: 1969 // - we're in C++ (where every function has a prototype), 1970 // - there is a prototype in the declarator, or 1971 // - the type R of the function is some kind of typedef or other reference 1972 // to a type name (which eventually refers to a function type). 1973 bool HasPrototype = 1974 getLangOptions().CPlusPlus || 1975 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 1976 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 1977 1978 NewFD = FunctionDecl::Create(Context, DC, 1979 D.getIdentifierLoc(), 1980 Name, R, SC, isInline, HasPrototype, 1981 // FIXME: Move to DeclGroup... 1982 D.getDeclSpec().getSourceRange().getBegin()); 1983 } 1984 1985 // Set the lexical context. If the declarator has a C++ 1986 // scope specifier, the lexical context will be different 1987 // from the semantic context. 1988 NewFD->setLexicalDeclContext(CurContext); 1989 1990 // C++ [dcl.fct.spec]p5: 1991 // The virtual specifier shall only be used in declarations of 1992 // nonstatic class member functions that appear within a 1993 // member-specification of a class declaration; see 10.3. 1994 // 1995 // FIXME: Checking the 'virtual' specifier is not sufficient. A 1996 // function is also virtual if it overrides an already virtual 1997 // function. This is important to do here because it's part of the 1998 // declaration. 1999 if (isVirtual && !InvalidDecl) { 2000 if (!isVirtualOkay) { 2001 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2002 diag::err_virtual_non_function); 2003 } else if (!CurContext->isRecord()) { 2004 // 'virtual' was specified outside of the class. 2005 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2006 << CodeModificationHint::CreateRemoval( 2007 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2008 } else { 2009 // Okay: Add virtual to the method. 2010 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2011 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2012 CurClass->setAggregate(false); 2013 CurClass->setPOD(false); 2014 CurClass->setPolymorphic(true); 2015 } 2016 } 2017 2018 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2019 !CurContext->isRecord()) { 2020 // C++ [class.static]p1: 2021 // A data or function member of a class may be declared static 2022 // in a class definition, in which case it is a static member of 2023 // the class. 2024 2025 // Complain about the 'static' specifier if it's on an out-of-line 2026 // member function definition. 2027 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2028 diag::err_static_out_of_line) 2029 << CodeModificationHint::CreateRemoval( 2030 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2031 } 2032 2033 // Handle GNU asm-label extension (encoded as an attribute). 2034 if (Expr *E = (Expr*) D.getAsmLabel()) { 2035 // The parser guarantees this is a string. 2036 StringLiteral *SE = cast<StringLiteral>(E); 2037 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2038 SE->getByteLength()))); 2039 } 2040 2041 // Copy the parameter declarations from the declarator D to 2042 // the function declaration NewFD, if they are available. 2043 if (D.getNumTypeObjects() > 0) { 2044 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2045 2046 // Create Decl objects for each parameter, adding them to the 2047 // FunctionDecl. 2048 llvm::SmallVector<ParmVarDecl*, 16> Params; 2049 2050 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2051 // function that takes no arguments, not a function that takes a 2052 // single void argument. 2053 // We let through "const void" here because Sema::GetTypeForDeclarator 2054 // already checks for that case. 2055 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2056 FTI.ArgInfo[0].Param && 2057 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2058 // empty arg list, don't push any params. 2059 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2060 2061 // In C++, the empty parameter-type-list must be spelled "void"; a 2062 // typedef of void is not permitted. 2063 if (getLangOptions().CPlusPlus && 2064 Param->getType().getUnqualifiedType() != Context.VoidTy) { 2065 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2066 } 2067 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2068 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2069 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2070 } 2071 2072 NewFD->setParams(Context, &Params[0], Params.size()); 2073 } else if (R->getAsTypedefType()) { 2074 // When we're declaring a function with a typedef, as in the 2075 // following example, we'll need to synthesize (unnamed) 2076 // parameters for use in the declaration. 2077 // 2078 // @code 2079 // typedef void fn(int); 2080 // fn f; 2081 // @endcode 2082 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 2083 if (!FT) { 2084 // This is a typedef of a function with no prototype, so we 2085 // don't need to do anything. 2086 } else if ((FT->getNumArgs() == 0) || 2087 (FT->getNumArgs() == 1 && !FT->isVariadic() && 2088 FT->getArgType(0)->isVoidType())) { 2089 // This is a zero-argument function. We don't need to do anything. 2090 } else { 2091 // Synthesize a parameter for each argument type. 2092 llvm::SmallVector<ParmVarDecl*, 16> Params; 2093 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 2094 ArgType != FT->arg_type_end(); ++ArgType) { 2095 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2096 SourceLocation(), 0, 2097 *ArgType, VarDecl::None, 2098 0); 2099 Param->setImplicit(); 2100 Params.push_back(Param); 2101 } 2102 2103 NewFD->setParams(Context, &Params[0], Params.size()); 2104 } 2105 } 2106 2107 // If name lookup finds a previous declaration that is not in the 2108 // same scope as the new declaration, this may still be an 2109 // acceptable redeclaration. 2110 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2111 !(NewFD->hasLinkage() && 2112 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2113 PrevDecl = 0; 2114 2115 // Perform semantic checking on the function declaration. 2116 bool OverloadableAttrRequired = false; // FIXME: HACK! 2117 if (CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2118 /*FIXME:*/OverloadableAttrRequired)) 2119 InvalidDecl = true; 2120 2121 if (D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2122 // An out-of-line member function declaration must also be a 2123 // definition (C++ [dcl.meaning]p1). 2124 if (!IsFunctionDefinition) { 2125 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2126 << D.getCXXScopeSpec().getRange(); 2127 InvalidDecl = true; 2128 } else if (!Redeclaration) { 2129 // The user tried to provide an out-of-line definition for a 2130 // function that is a member of a class or namespace, but there 2131 // was no such member function declared (C++ [class.mfct]p2, 2132 // C++ [namespace.memdef]p2). For example: 2133 // 2134 // class X { 2135 // void f() const; 2136 // }; 2137 // 2138 // void X::f() { } // ill-formed 2139 // 2140 // Complain about this problem, and attempt to suggest close 2141 // matches (e.g., those that differ only in cv-qualifiers and 2142 // whether the parameter types are references). 2143 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2144 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2145 InvalidDecl = true; 2146 2147 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2148 true); 2149 assert(!Prev.isAmbiguous() && 2150 "Cannot have an ambiguity in previous-declaration lookup"); 2151 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2152 Func != FuncEnd; ++Func) { 2153 if (isa<FunctionDecl>(*Func) && 2154 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2155 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2156 } 2157 2158 PrevDecl = 0; 2159 } 2160 } 2161 2162 // Handle attributes. We need to have merged decls when handling attributes 2163 // (for example to check for conflicts, etc). 2164 // FIXME: This needs to happen before we merge declarations. Then, 2165 // let attribute merging cope with attribute conflicts. 2166 ProcessDeclAttributes(NewFD, D); 2167 AddKnownFunctionAttributes(NewFD); 2168 2169 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2170 // If a function name is overloadable in C, then every function 2171 // with that name must be marked "overloadable". 2172 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2173 << Redeclaration << NewFD; 2174 if (PrevDecl) 2175 Diag(PrevDecl->getLocation(), 2176 diag::note_attribute_overloadable_prev_overload); 2177 NewFD->addAttr(::new (Context) OverloadableAttr()); 2178 } 2179 2180 // If this is a locally-scoped extern C function, update the 2181 // map of such names. 2182 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2183 && !InvalidDecl) 2184 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2185 2186 return NewFD; 2187} 2188 2189/// \brief Perform semantic checking of a new function declaration. 2190/// 2191/// Performs semantic analysis of the new function declaration 2192/// NewFD. This routine performs all semantic checking that does not 2193/// require the actual declarator involved in the declaration, and is 2194/// used both for the declaration of functions as they are parsed 2195/// (called via ActOnDeclarator) and for the declaration of functions 2196/// that have been instantiated via C++ template instantiation (called 2197/// via InstantiateDecl). 2198/// 2199/// \returns true if there was an error, false otherwise. 2200bool Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2201 bool &Redeclaration, 2202 bool &OverloadableAttrRequired) { 2203 bool InvalidDecl = false; 2204 2205 // Semantic checking for this function declaration (in isolation). 2206 if (getLangOptions().CPlusPlus) { 2207 // C++-specific checks. 2208 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 2209 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 2210 else if (isa<CXXDestructorDecl>(NewFD)) { 2211 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2212 Record->setUserDeclaredDestructor(true); 2213 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2214 // user-defined destructor. 2215 Record->setPOD(false); 2216 } else if (CXXConversionDecl *Conversion 2217 = dyn_cast<CXXConversionDecl>(NewFD)) 2218 ActOnConversionDeclarator(Conversion); 2219 2220 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2221 if (NewFD->isOverloadedOperator() && 2222 CheckOverloadedOperatorDeclaration(NewFD)) 2223 InvalidDecl = true; 2224 } 2225 2226 // Check for a previous declaration of this name. 2227 if (!PrevDecl && NewFD->isExternC(Context)) { 2228 // Since we did not find anything by this name and we're declaring 2229 // an extern "C" function, look for a non-visible extern "C" 2230 // declaration with the same name. 2231 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2232 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2233 if (Pos != LocallyScopedExternalDecls.end()) 2234 PrevDecl = Pos->second; 2235 } 2236 2237 // Merge or overload the declaration with an existing declaration of 2238 // the same name, if appropriate. 2239 if (PrevDecl) { 2240 // Determine whether NewFD is an overload of PrevDecl or 2241 // a declaration that requires merging. If it's an overload, 2242 // there's no more work to do here; we'll just add the new 2243 // function to the scope. 2244 OverloadedFunctionDecl::function_iterator MatchedDecl; 2245 2246 if (!getLangOptions().CPlusPlus && 2247 AllowOverloadingOfFunction(PrevDecl, Context)) { 2248 OverloadableAttrRequired = true; 2249 2250 // Functions marked "overloadable" must have a prototype (that 2251 // we can't get through declaration merging). 2252 if (!NewFD->getType()->getAsFunctionProtoType()) { 2253 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2254 << NewFD; 2255 InvalidDecl = true; 2256 Redeclaration = true; 2257 2258 // Turn this into a variadic function with no parameters. 2259 QualType R = Context.getFunctionType( 2260 NewFD->getType()->getAsFunctionType()->getResultType(), 2261 0, 0, true, 0); 2262 NewFD->setType(R); 2263 } 2264 } 2265 2266 if (PrevDecl && 2267 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2268 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2269 Redeclaration = true; 2270 Decl *OldDecl = PrevDecl; 2271 2272 // If PrevDecl was an overloaded function, extract the 2273 // FunctionDecl that matched. 2274 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2275 OldDecl = *MatchedDecl; 2276 2277 // NewFD and OldDecl represent declarations that need to be 2278 // merged. 2279 if (MergeFunctionDecl(NewFD, OldDecl)) 2280 InvalidDecl = true; 2281 2282 if (!InvalidDecl) 2283 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2284 } 2285 } 2286 2287 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) { 2288 // In C++, check default arguments now that we have merged decls. Unless 2289 // the lexical context is the class, because in this case this is done 2290 // during delayed parsing anyway. 2291 CheckCXXDefaultArguments(NewFD); 2292 } 2293 2294 return InvalidDecl || NewFD->isInvalidDecl(); 2295} 2296 2297bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2298 // FIXME: Need strict checking. In C89, we need to check for 2299 // any assignment, increment, decrement, function-calls, or 2300 // commas outside of a sizeof. In C99, it's the same list, 2301 // except that the aforementioned are allowed in unevaluated 2302 // expressions. Everything else falls under the 2303 // "may accept other forms of constant expressions" exception. 2304 // (We never end up here for C++, so the constant expression 2305 // rules there don't matter.) 2306 if (Init->isConstantInitializer(Context)) 2307 return false; 2308 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2309 << Init->getSourceRange(); 2310 return true; 2311} 2312 2313void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2314 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2315} 2316 2317/// AddInitializerToDecl - Adds the initializer Init to the 2318/// declaration dcl. If DirectInit is true, this is C++ direct 2319/// initialization rather than copy initialization. 2320void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2321 Decl *RealDecl = dcl.getAs<Decl>(); 2322 // If there is no declaration, there was an error parsing it. Just ignore 2323 // the initializer. 2324 if (RealDecl == 0) 2325 return; 2326 2327 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2328 // With declarators parsed the way they are, the parser cannot 2329 // distinguish between a normal initializer and a pure-specifier. 2330 // Thus this grotesque test. 2331 IntegerLiteral *IL; 2332 Expr *Init = static_cast<Expr *>(init.get()); 2333 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2334 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2335 if (Method->isVirtual()) { 2336 Method->setPure(); 2337 2338 // A class is abstract if at least one function is pure virtual. 2339 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2340 } else if (!Method->isInvalidDecl()) { 2341 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2342 << Method->getDeclName() << Init->getSourceRange(); 2343 Method->setInvalidDecl(); 2344 } 2345 } else { 2346 Diag(Method->getLocation(), diag::err_member_function_initialization) 2347 << Method->getDeclName() << Init->getSourceRange(); 2348 Method->setInvalidDecl(); 2349 } 2350 return; 2351 } 2352 2353 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2354 if (!VDecl) { 2355 if (getLangOptions().CPlusPlus && 2356 RealDecl->getLexicalDeclContext()->isRecord() && 2357 isa<NamedDecl>(RealDecl)) 2358 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2359 << cast<NamedDecl>(RealDecl)->getDeclName(); 2360 else 2361 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2362 RealDecl->setInvalidDecl(); 2363 return; 2364 } 2365 2366 const VarDecl *Def = 0; 2367 if (VDecl->getDefinition(Def)) { 2368 Diag(VDecl->getLocation(), diag::err_redefinition) 2369 << VDecl->getDeclName(); 2370 Diag(Def->getLocation(), diag::note_previous_definition); 2371 VDecl->setInvalidDecl(); 2372 return; 2373 } 2374 2375 // Take ownership of the expression, now that we're sure we have somewhere 2376 // to put it. 2377 Expr *Init = static_cast<Expr *>(init.release()); 2378 assert(Init && "missing initializer"); 2379 2380 // Get the decls type and save a reference for later, since 2381 // CheckInitializerTypes may change it. 2382 QualType DclT = VDecl->getType(), SavT = DclT; 2383 if (VDecl->isBlockVarDecl()) { 2384 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2385 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2386 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2387 VDecl->setInvalidDecl(); 2388 } else if (!VDecl->isInvalidDecl()) { 2389 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2390 VDecl->getDeclName(), DirectInit)) 2391 VDecl->setInvalidDecl(); 2392 2393 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2394 // Don't check invalid declarations to avoid emitting useless diagnostics. 2395 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2396 if (SC == VarDecl::Static) // C99 6.7.8p4. 2397 CheckForConstantInitializer(Init, DclT); 2398 } 2399 } 2400 } else if (VDecl->isStaticDataMember() && 2401 VDecl->getLexicalDeclContext()->isRecord()) { 2402 // This is an in-class initialization for a static data member, e.g., 2403 // 2404 // struct S { 2405 // static const int value = 17; 2406 // }; 2407 2408 // Attach the initializer 2409 VDecl->setInit(Init); 2410 2411 // C++ [class.mem]p4: 2412 // A member-declarator can contain a constant-initializer only 2413 // if it declares a static member (9.4) of const integral or 2414 // const enumeration type, see 9.4.2. 2415 QualType T = VDecl->getType(); 2416 if (!T->isDependentType() && 2417 (!Context.getCanonicalType(T).isConstQualified() || 2418 !T->isIntegralType())) { 2419 Diag(VDecl->getLocation(), diag::err_member_initialization) 2420 << VDecl->getDeclName() << Init->getSourceRange(); 2421 VDecl->setInvalidDecl(); 2422 } else { 2423 // C++ [class.static.data]p4: 2424 // If a static data member is of const integral or const 2425 // enumeration type, its declaration in the class definition 2426 // can specify a constant-initializer which shall be an 2427 // integral constant expression (5.19). 2428 if (!Init->isTypeDependent() && 2429 !Init->getType()->isIntegralType()) { 2430 // We have a non-dependent, non-integral or enumeration type. 2431 Diag(Init->getSourceRange().getBegin(), 2432 diag::err_in_class_initializer_non_integral_type) 2433 << Init->getType() << Init->getSourceRange(); 2434 VDecl->setInvalidDecl(); 2435 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2436 // Check whether the expression is a constant expression. 2437 llvm::APSInt Value; 2438 SourceLocation Loc; 2439 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2440 Diag(Loc, diag::err_in_class_initializer_non_constant) 2441 << Init->getSourceRange(); 2442 VDecl->setInvalidDecl(); 2443 } else if (!VDecl->getType()->isDependentType()) 2444 ImpCastExprToType(Init, VDecl->getType()); 2445 } 2446 } 2447 } else if (VDecl->isFileVarDecl()) { 2448 if (VDecl->getStorageClass() == VarDecl::Extern) 2449 Diag(VDecl->getLocation(), diag::warn_extern_init); 2450 if (!VDecl->isInvalidDecl()) 2451 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2452 VDecl->getDeclName(), DirectInit)) 2453 VDecl->setInvalidDecl(); 2454 2455 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2456 // Don't check invalid declarations to avoid emitting useless diagnostics. 2457 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2458 // C99 6.7.8p4. All file scoped initializers need to be constant. 2459 CheckForConstantInitializer(Init, DclT); 2460 } 2461 } 2462 // If the type changed, it means we had an incomplete type that was 2463 // completed by the initializer. For example: 2464 // int ary[] = { 1, 3, 5 }; 2465 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2466 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2467 VDecl->setType(DclT); 2468 Init->setType(DclT); 2469 } 2470 2471 // Attach the initializer to the decl. 2472 VDecl->setInit(Init); 2473 return; 2474} 2475 2476void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2477 Decl *RealDecl = dcl.getAs<Decl>(); 2478 2479 // If there is no declaration, there was an error parsing it. Just ignore it. 2480 if (RealDecl == 0) 2481 return; 2482 2483 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2484 QualType Type = Var->getType(); 2485 // C++ [dcl.init.ref]p3: 2486 // The initializer can be omitted for a reference only in a 2487 // parameter declaration (8.3.5), in the declaration of a 2488 // function return type, in the declaration of a class member 2489 // within its class declaration (9.2), and where the extern 2490 // specifier is explicitly used. 2491 if (Type->isReferenceType() && 2492 Var->getStorageClass() != VarDecl::Extern && 2493 Var->getStorageClass() != VarDecl::PrivateExtern) { 2494 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2495 << Var->getDeclName() 2496 << SourceRange(Var->getLocation(), Var->getLocation()); 2497 Var->setInvalidDecl(); 2498 return; 2499 } 2500 2501 // C++ [dcl.init]p9: 2502 // 2503 // If no initializer is specified for an object, and the object 2504 // is of (possibly cv-qualified) non-POD class type (or array 2505 // thereof), the object shall be default-initialized; if the 2506 // object is of const-qualified type, the underlying class type 2507 // shall have a user-declared default constructor. 2508 if (getLangOptions().CPlusPlus) { 2509 QualType InitType = Type; 2510 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2511 InitType = Array->getElementType(); 2512 if (Var->getStorageClass() != VarDecl::Extern && 2513 Var->getStorageClass() != VarDecl::PrivateExtern && 2514 InitType->isRecordType()) { 2515 const CXXConstructorDecl *Constructor = 0; 2516 if (!RequireCompleteType(Var->getLocation(), InitType, 2517 diag::err_invalid_incomplete_type_use)) 2518 Constructor 2519 = PerformInitializationByConstructor(InitType, 0, 0, 2520 Var->getLocation(), 2521 SourceRange(Var->getLocation(), 2522 Var->getLocation()), 2523 Var->getDeclName(), 2524 IK_Default); 2525 if (!Constructor) 2526 Var->setInvalidDecl(); 2527 } 2528 } 2529 2530#if 0 2531 // FIXME: Temporarily disabled because we are not properly parsing 2532 // linkage specifications on declarations, e.g., 2533 // 2534 // extern "C" const CGPoint CGPointerZero; 2535 // 2536 // C++ [dcl.init]p9: 2537 // 2538 // If no initializer is specified for an object, and the 2539 // object is of (possibly cv-qualified) non-POD class type (or 2540 // array thereof), the object shall be default-initialized; if 2541 // the object is of const-qualified type, the underlying class 2542 // type shall have a user-declared default 2543 // constructor. Otherwise, if no initializer is specified for 2544 // an object, the object and its subobjects, if any, have an 2545 // indeterminate initial value; if the object or any of its 2546 // subobjects are of const-qualified type, the program is 2547 // ill-formed. 2548 // 2549 // This isn't technically an error in C, so we don't diagnose it. 2550 // 2551 // FIXME: Actually perform the POD/user-defined default 2552 // constructor check. 2553 if (getLangOptions().CPlusPlus && 2554 Context.getCanonicalType(Type).isConstQualified() && 2555 Var->getStorageClass() != VarDecl::Extern) 2556 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2557 << Var->getName() 2558 << SourceRange(Var->getLocation(), Var->getLocation()); 2559#endif 2560 } 2561} 2562 2563Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2564 unsigned NumDecls) { 2565 llvm::SmallVector<Decl*, 8> Decls; 2566 2567 for (unsigned i = 0; i != NumDecls; ++i) 2568 if (Decl *D = Group[i].getAs<Decl>()) 2569 Decls.push_back(D); 2570 2571 // Perform semantic analysis that depends on having fully processed both 2572 // the declarator and initializer. 2573 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2574 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2575 if (!IDecl) 2576 continue; 2577 QualType T = IDecl->getType(); 2578 2579 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2580 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2581 if (IDecl->isBlockVarDecl() && 2582 IDecl->getStorageClass() != VarDecl::Extern) { 2583 if (!IDecl->isInvalidDecl() && 2584 RequireCompleteType(IDecl->getLocation(), T, 2585 diag::err_typecheck_decl_incomplete_type)) 2586 IDecl->setInvalidDecl(); 2587 } 2588 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2589 // object that has file scope without an initializer, and without a 2590 // storage-class specifier or with the storage-class specifier "static", 2591 // constitutes a tentative definition. Note: A tentative definition with 2592 // external linkage is valid (C99 6.2.2p5). 2593 if (IDecl->isTentativeDefinition(Context)) { 2594 QualType CheckType = T; 2595 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2596 2597 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2598 if (ArrayT) { 2599 CheckType = ArrayT->getElementType(); 2600 DiagID = diag::err_illegal_decl_array_incomplete_type; 2601 } 2602 2603 if (IDecl->isInvalidDecl()) { 2604 // Do nothing with invalid declarations 2605 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2606 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2607 // C99 6.9.2p3: If the declaration of an identifier for an object is 2608 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2609 // declared type shall not be an incomplete type. 2610 IDecl->setInvalidDecl(); 2611 } 2612 } 2613 } 2614 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2615 &Decls[0], NumDecls)); 2616} 2617 2618 2619/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2620/// to introduce parameters into function prototype scope. 2621Sema::DeclPtrTy 2622Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2623 const DeclSpec &DS = D.getDeclSpec(); 2624 2625 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2626 VarDecl::StorageClass StorageClass = VarDecl::None; 2627 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2628 StorageClass = VarDecl::Register; 2629 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2630 Diag(DS.getStorageClassSpecLoc(), 2631 diag::err_invalid_storage_class_in_func_decl); 2632 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2633 } 2634 if (DS.isThreadSpecified()) { 2635 Diag(DS.getThreadSpecLoc(), 2636 diag::err_invalid_storage_class_in_func_decl); 2637 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2638 } 2639 DiagnoseFunctionSpecifiers(D); 2640 2641 // Check that there are no default arguments inside the type of this 2642 // parameter (C++ only). 2643 if (getLangOptions().CPlusPlus) 2644 CheckExtraCXXDefaultArguments(D); 2645 2646 // In this context, we *do not* check D.getInvalidType(). If the declarator 2647 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2648 // though it will not reflect the user specified type. 2649 QualType parmDeclType = GetTypeForDeclarator(D, S); 2650 2651 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2652 2653 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2654 // Can this happen for params? We already checked that they don't conflict 2655 // among each other. Here they can only shadow globals, which is ok. 2656 IdentifierInfo *II = D.getIdentifier(); 2657 if (II) { 2658 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2659 if (PrevDecl->isTemplateParameter()) { 2660 // Maybe we will complain about the shadowed template parameter. 2661 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2662 // Just pretend that we didn't see the previous declaration. 2663 PrevDecl = 0; 2664 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2665 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2666 2667 // Recover by removing the name 2668 II = 0; 2669 D.SetIdentifier(0, D.getIdentifierLoc()); 2670 } 2671 } 2672 } 2673 2674 // Parameters can not be abstract class types. 2675 // For record types, this is done by the AbstractClassUsageDiagnoser once 2676 // the class has been completely parsed. 2677 if (!CurContext->isRecord() && 2678 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2679 diag::err_abstract_type_in_decl, 2680 AbstractParamType)) 2681 D.setInvalidType(true); 2682 2683 QualType T = adjustParameterType(parmDeclType); 2684 2685 ParmVarDecl *New; 2686 if (T == parmDeclType) // parameter type did not need adjustment 2687 New = ParmVarDecl::Create(Context, CurContext, 2688 D.getIdentifierLoc(), II, 2689 parmDeclType, StorageClass, 2690 0); 2691 else // keep track of both the adjusted and unadjusted types 2692 New = OriginalParmVarDecl::Create(Context, CurContext, 2693 D.getIdentifierLoc(), II, T, 2694 parmDeclType, StorageClass, 0); 2695 2696 if (D.getInvalidType()) 2697 New->setInvalidDecl(); 2698 2699 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2700 if (D.getCXXScopeSpec().isSet()) { 2701 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2702 << D.getCXXScopeSpec().getRange(); 2703 New->setInvalidDecl(); 2704 } 2705 // Parameter declarators cannot be interface types. All ObjC objects are 2706 // passed by reference. 2707 if (T->isObjCInterfaceType()) { 2708 Diag(D.getIdentifierLoc(), diag::err_object_cannot_be_by_value) 2709 << "passed"; 2710 New->setInvalidDecl(); 2711 } 2712 2713 // Add the parameter declaration into this scope. 2714 S->AddDecl(DeclPtrTy::make(New)); 2715 if (II) 2716 IdResolver.AddDecl(New); 2717 2718 ProcessDeclAttributes(New, D); 2719 return DeclPtrTy::make(New); 2720} 2721 2722void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2723 SourceLocation LocAfterDecls) { 2724 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2725 "Not a function declarator!"); 2726 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2727 2728 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2729 // for a K&R function. 2730 if (!FTI.hasPrototype) { 2731 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2732 --i; 2733 if (FTI.ArgInfo[i].Param == 0) { 2734 std::string Code = " int "; 2735 Code += FTI.ArgInfo[i].Ident->getName(); 2736 Code += ";\n"; 2737 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2738 << FTI.ArgInfo[i].Ident 2739 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2740 2741 // Implicitly declare the argument as type 'int' for lack of a better 2742 // type. 2743 DeclSpec DS; 2744 const char* PrevSpec; // unused 2745 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2746 PrevSpec); 2747 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2748 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2749 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2750 } 2751 } 2752 } 2753} 2754 2755Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2756 Declarator &D) { 2757 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2758 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2759 "Not a function declarator!"); 2760 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2761 2762 if (FTI.hasPrototype) { 2763 // FIXME: Diagnose arguments without names in C. 2764 } 2765 2766 Scope *ParentScope = FnBodyScope->getParent(); 2767 2768 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2769 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2770} 2771 2772Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2773 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2774 2775 // See if this is a redefinition. 2776 const FunctionDecl *Definition; 2777 if (FD->getBody(Definition)) { 2778 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2779 Diag(Definition->getLocation(), diag::note_previous_definition); 2780 } 2781 2782 // Builtin functions cannot be defined. 2783 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2784 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2785 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2786 FD->setInvalidDecl(); 2787 } 2788 } 2789 2790 // The return type of a function definition must be complete 2791 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2792 QualType ResultType = FD->getResultType(); 2793 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2794 RequireCompleteType(FD->getLocation(), ResultType, 2795 diag::err_func_def_incomplete_result)) 2796 FD->setInvalidDecl(); 2797 2798 // GNU warning -Wmissing-prototypes: 2799 // Warn if a global function is defined without a previous 2800 // prototype declaration. This warning is issued even if the 2801 // definition itself provides a prototype. The aim is to detect 2802 // global functions that fail to be declared in header files. 2803 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2804 !FD->isMain()) { 2805 bool MissingPrototype = true; 2806 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2807 Prev; Prev = Prev->getPreviousDeclaration()) { 2808 // Ignore any declarations that occur in function or method 2809 // scope, because they aren't visible from the header. 2810 if (Prev->getDeclContext()->isFunctionOrMethod()) 2811 continue; 2812 2813 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2814 break; 2815 } 2816 2817 if (MissingPrototype) 2818 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2819 } 2820 2821 PushDeclContext(FnBodyScope, FD); 2822 2823 // Check the validity of our function parameters 2824 CheckParmsForFunctionDef(FD); 2825 2826 // Introduce our parameters into the function scope 2827 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2828 ParmVarDecl *Param = FD->getParamDecl(p); 2829 Param->setOwningFunction(FD); 2830 2831 // If this has an identifier, add it to the scope stack. 2832 if (Param->getIdentifier()) 2833 PushOnScopeChains(Param, FnBodyScope); 2834 } 2835 2836 // Checking attributes of current function definition 2837 // dllimport attribute. 2838 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2839 // dllimport attribute cannot be applied to definition. 2840 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2841 Diag(FD->getLocation(), 2842 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2843 << "dllimport"; 2844 FD->setInvalidDecl(); 2845 return DeclPtrTy::make(FD); 2846 } else { 2847 // If a symbol previously declared dllimport is later defined, the 2848 // attribute is ignored in subsequent references, and a warning is 2849 // emitted. 2850 Diag(FD->getLocation(), 2851 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2852 << FD->getNameAsCString() << "dllimport"; 2853 } 2854 } 2855 return DeclPtrTy::make(FD); 2856} 2857 2858static bool StatementCreatesScope(Stmt* S) { 2859 bool result = false; 2860 if (DeclStmt* DS = dyn_cast<DeclStmt>(S)) { 2861 for (DeclStmt::decl_iterator i = DS->decl_begin(); 2862 i != DS->decl_end(); ++i) { 2863 if (VarDecl* D = dyn_cast<VarDecl>(*i)) { 2864 result |= D->getType()->isVariablyModifiedType(); 2865 result |= !!D->getAttr<CleanupAttr>(); 2866 } else if (TypedefDecl* D = dyn_cast<TypedefDecl>(*i)) { 2867 result |= D->getUnderlyingType()->isVariablyModifiedType(); 2868 } 2869 } 2870 } 2871 2872 return result; 2873} 2874 2875void Sema::RecursiveCalcLabelScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2876 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2877 std::vector<void*>& ScopeStack, 2878 Stmt* CurStmt, 2879 Stmt* ParentCompoundStmt) { 2880 for (Stmt::child_iterator i = CurStmt->child_begin(); 2881 i != CurStmt->child_end(); ++i) { 2882 if (!*i) continue; 2883 if (StatementCreatesScope(*i)) { 2884 ScopeStack.push_back(*i); 2885 PopScopeMap[*i] = ParentCompoundStmt; 2886 } else if (isa<LabelStmt>(CurStmt)) { 2887 LabelScopeMap[CurStmt] = ScopeStack.size() ? ScopeStack.back() : 0; 2888 } 2889 if (isa<DeclStmt>(*i)) continue; 2890 Stmt* CurCompound = isa<CompoundStmt>(*i) ? *i : ParentCompoundStmt; 2891 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, 2892 *i, CurCompound); 2893 } 2894 2895 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2896 ScopeStack.pop_back(); 2897 } 2898} 2899 2900void Sema::RecursiveCalcJumpScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2901 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2902 llvm::DenseMap<Stmt*, void*>& GotoScopeMap, 2903 std::vector<void*>& ScopeStack, 2904 Stmt* CurStmt) { 2905 for (Stmt::child_iterator i = CurStmt->child_begin(); 2906 i != CurStmt->child_end(); ++i) { 2907 if (!*i) continue; 2908 if (StatementCreatesScope(*i)) { 2909 ScopeStack.push_back(*i); 2910 } else if (GotoStmt* GS = dyn_cast<GotoStmt>(*i)) { 2911 void* LScope = LabelScopeMap[GS->getLabel()]; 2912 if (LScope) { 2913 bool foundScopeInStack = false; 2914 for (unsigned i = ScopeStack.size(); i > 0; --i) { 2915 if (LScope == ScopeStack[i-1]) { 2916 foundScopeInStack = true; 2917 break; 2918 } 2919 } 2920 if (!foundScopeInStack) { 2921 Diag(GS->getSourceRange().getBegin(), diag::err_goto_into_scope); 2922 } 2923 } 2924 } 2925 if (isa<DeclStmt>(*i)) continue; 2926 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, 2927 ScopeStack, *i); 2928 } 2929 2930 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2931 ScopeStack.pop_back(); 2932 } 2933} 2934 2935Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 2936 Decl *dcl = D.getAs<Decl>(); 2937 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2938 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2939 FD->setBody(cast<CompoundStmt>(Body)); 2940 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2941 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2942 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2943 MD->setBody(cast<CompoundStmt>(Body)); 2944 } else { 2945 Body->Destroy(Context); 2946 return DeclPtrTy(); 2947 } 2948 PopDeclContext(); 2949 // Verify and clean out per-function state. 2950 2951 bool HaveLabels = !LabelMap.empty(); 2952 // Check goto/label use. 2953 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2954 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2955 // Verify that we have no forward references left. If so, there was a goto 2956 // or address of a label taken, but no definition of it. Label fwd 2957 // definitions are indicated with a null substmt. 2958 if (I->second->getSubStmt() == 0) { 2959 LabelStmt *L = I->second; 2960 // Emit error. 2961 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2962 2963 // At this point, we have gotos that use the bogus label. Stitch it into 2964 // the function body so that they aren't leaked and that the AST is well 2965 // formed. 2966 if (Body) { 2967#if 0 2968 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2969 // and the AST is malformed anyway. We should just blow away 'L'. 2970 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2971 cast<CompoundStmt>(Body)->push_back(L); 2972#else 2973 L->Destroy(Context); 2974#endif 2975 } else { 2976 // The whole function wasn't parsed correctly, just delete this. 2977 L->Destroy(Context); 2978 } 2979 } 2980 } 2981 LabelMap.clear(); 2982 2983 if (!Body) return D; 2984 2985 if (HaveLabels) { 2986 llvm::DenseMap<Stmt*, void*> LabelScopeMap; 2987 llvm::DenseMap<void*, Stmt*> PopScopeMap; 2988 llvm::DenseMap<Stmt*, void*> GotoScopeMap; 2989 std::vector<void*> ScopeStack; 2990 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, Body, Body); 2991 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, ScopeStack, Body); 2992 } 2993 2994 return D; 2995} 2996 2997/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2998/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2999NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3000 IdentifierInfo &II, Scope *S) { 3001 // Before we produce a declaration for an implicitly defined 3002 // function, see whether there was a locally-scoped declaration of 3003 // this name as a function or variable. If so, use that 3004 // (non-visible) declaration, and complain about it. 3005 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3006 = LocallyScopedExternalDecls.find(&II); 3007 if (Pos != LocallyScopedExternalDecls.end()) { 3008 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3009 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3010 return Pos->second; 3011 } 3012 3013 // Extension in C99. Legal in C90, but warn about it. 3014 if (getLangOptions().C99) 3015 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3016 else 3017 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3018 3019 // FIXME: handle stuff like: 3020 // void foo() { extern float X(); } 3021 // void bar() { X(); } <-- implicit decl for X in another scope. 3022 3023 // Set a Declarator for the implicit definition: int foo(); 3024 const char *Dummy; 3025 DeclSpec DS; 3026 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3027 Error = Error; // Silence warning. 3028 assert(!Error && "Error setting up implicit decl!"); 3029 Declarator D(DS, Declarator::BlockContext); 3030 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3031 0, 0, 0, Loc, D), 3032 SourceLocation()); 3033 D.SetIdentifier(&II, Loc); 3034 3035 // Insert this function into translation-unit scope. 3036 3037 DeclContext *PrevDC = CurContext; 3038 CurContext = Context.getTranslationUnitDecl(); 3039 3040 FunctionDecl *FD = 3041 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3042 FD->setImplicit(); 3043 3044 CurContext = PrevDC; 3045 3046 AddKnownFunctionAttributes(FD); 3047 3048 return FD; 3049} 3050 3051/// \brief Adds any function attributes that we know a priori based on 3052/// the declaration of this function. 3053/// 3054/// These attributes can apply both to implicitly-declared builtins 3055/// (like __builtin___printf_chk) or to library-declared functions 3056/// like NSLog or printf. 3057void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3058 if (FD->isInvalidDecl()) 3059 return; 3060 3061 // If this is a built-in function, map its builtin attributes to 3062 // actual attributes. 3063 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3064 // Handle printf-formatting attributes. 3065 unsigned FormatIdx; 3066 bool HasVAListArg; 3067 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3068 if (!FD->getAttr<FormatAttr>()) 3069 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3070 FormatIdx + 2)); 3071 } 3072 3073 // Mark const if we don't care about errno and that is the only 3074 // thing preventing the function from being const. This allows 3075 // IRgen to use LLVM intrinsics for such functions. 3076 if (!getLangOptions().MathErrno && 3077 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3078 if (!FD->getAttr<ConstAttr>()) 3079 FD->addAttr(::new (Context) ConstAttr()); 3080 } 3081 } 3082 3083 IdentifierInfo *Name = FD->getIdentifier(); 3084 if (!Name) 3085 return; 3086 if ((!getLangOptions().CPlusPlus && 3087 FD->getDeclContext()->isTranslationUnit()) || 3088 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3089 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3090 LinkageSpecDecl::lang_c)) { 3091 // Okay: this could be a libc/libm/Objective-C function we know 3092 // about. 3093 } else 3094 return; 3095 3096 unsigned KnownID; 3097 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3098 if (KnownFunctionIDs[KnownID] == Name) 3099 break; 3100 3101 switch (KnownID) { 3102 case id_NSLog: 3103 case id_NSLogv: 3104 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3105 // FIXME: We known better than our headers. 3106 const_cast<FormatAttr *>(Format)->setType("printf"); 3107 } else 3108 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3109 break; 3110 3111 case id_asprintf: 3112 case id_vasprintf: 3113 if (!FD->getAttr<FormatAttr>()) 3114 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3115 break; 3116 3117 default: 3118 // Unknown function or known function without any attributes to 3119 // add. Do nothing. 3120 break; 3121 } 3122} 3123 3124TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3125 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3126 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3127 3128 // Scope manipulation handled by caller. 3129 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3130 D.getIdentifierLoc(), 3131 D.getIdentifier(), 3132 T); 3133 3134 if (TagType *TT = dyn_cast<TagType>(T)) { 3135 TagDecl *TD = TT->getDecl(); 3136 3137 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3138 // keep track of the TypedefDecl. 3139 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3140 TD->setTypedefForAnonDecl(NewTD); 3141 } 3142 3143 if (D.getInvalidType()) 3144 NewTD->setInvalidDecl(); 3145 return NewTD; 3146} 3147 3148/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3149/// former case, Name will be non-null. In the later case, Name will be null. 3150/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3151/// reference/declaration/definition of a tag. 3152Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3153 SourceLocation KWLoc, const CXXScopeSpec &SS, 3154 IdentifierInfo *Name, SourceLocation NameLoc, 3155 AttributeList *Attr, AccessSpecifier AS) { 3156 // If this is not a definition, it must have a name. 3157 assert((Name != 0 || TK == TK_Definition) && 3158 "Nameless record must be a definition!"); 3159 3160 TagDecl::TagKind Kind; 3161 switch (TagSpec) { 3162 default: assert(0 && "Unknown tag type!"); 3163 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3164 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3165 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3166 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3167 } 3168 3169 DeclContext *SearchDC = CurContext; 3170 DeclContext *DC = CurContext; 3171 NamedDecl *PrevDecl = 0; 3172 3173 bool Invalid = false; 3174 3175 if (Name && SS.isNotEmpty()) { 3176 // We have a nested-name tag ('struct foo::bar'). 3177 3178 // Check for invalid 'foo::'. 3179 if (SS.isInvalid()) { 3180 Name = 0; 3181 goto CreateNewDecl; 3182 } 3183 3184 // FIXME: RequireCompleteDeclContext(SS)? 3185 DC = computeDeclContext(SS); 3186 SearchDC = DC; 3187 // Look-up name inside 'foo::'. 3188 PrevDecl = dyn_cast_or_null<TagDecl>( 3189 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3190 3191 // A tag 'foo::bar' must already exist. 3192 if (PrevDecl == 0) { 3193 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3194 Name = 0; 3195 goto CreateNewDecl; 3196 } 3197 } else if (Name) { 3198 // If this is a named struct, check to see if there was a previous forward 3199 // declaration or definition. 3200 // FIXME: We're looking into outer scopes here, even when we 3201 // shouldn't be. Doing so can result in ambiguities that we 3202 // shouldn't be diagnosing. 3203 LookupResult R = LookupName(S, Name, LookupTagName, 3204 /*RedeclarationOnly=*/(TK != TK_Reference)); 3205 if (R.isAmbiguous()) { 3206 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3207 // FIXME: This is not best way to recover from case like: 3208 // 3209 // struct S s; 3210 // 3211 // causes needless "incomplete type" error later. 3212 Name = 0; 3213 PrevDecl = 0; 3214 Invalid = true; 3215 } 3216 else 3217 PrevDecl = R; 3218 3219 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3220 // FIXME: This makes sure that we ignore the contexts associated 3221 // with C structs, unions, and enums when looking for a matching 3222 // tag declaration or definition. See the similar lookup tweak 3223 // in Sema::LookupName; is there a better way to deal with this? 3224 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3225 SearchDC = SearchDC->getParent(); 3226 } 3227 } 3228 3229 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3230 // Maybe we will complain about the shadowed template parameter. 3231 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3232 // Just pretend that we didn't see the previous declaration. 3233 PrevDecl = 0; 3234 } 3235 3236 if (PrevDecl) { 3237 // Check whether the previous declaration is usable. 3238 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3239 3240 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3241 // If this is a use of a previous tag, or if the tag is already declared 3242 // in the same scope (so that the definition/declaration completes or 3243 // rementions the tag), reuse the decl. 3244 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3245 // Make sure that this wasn't declared as an enum and now used as a 3246 // struct or something similar. 3247 if (PrevTagDecl->getTagKind() != Kind) { 3248 bool SafeToContinue 3249 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3250 Kind != TagDecl::TK_enum); 3251 if (SafeToContinue) 3252 Diag(KWLoc, diag::err_use_with_wrong_tag) 3253 << Name 3254 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3255 PrevTagDecl->getKindName()); 3256 else 3257 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3258 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3259 3260 if (SafeToContinue) 3261 Kind = PrevTagDecl->getTagKind(); 3262 else { 3263 // Recover by making this an anonymous redefinition. 3264 Name = 0; 3265 PrevDecl = 0; 3266 Invalid = true; 3267 } 3268 } 3269 3270 if (!Invalid) { 3271 // If this is a use, just return the declaration we found. 3272 3273 // FIXME: In the future, return a variant or some other clue 3274 // for the consumer of this Decl to know it doesn't own it. 3275 // For our current ASTs this shouldn't be a problem, but will 3276 // need to be changed with DeclGroups. 3277 if (TK == TK_Reference) 3278 return DeclPtrTy::make(PrevDecl); 3279 3280 // Diagnose attempts to redefine a tag. 3281 if (TK == TK_Definition) { 3282 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3283 Diag(NameLoc, diag::err_redefinition) << Name; 3284 Diag(Def->getLocation(), diag::note_previous_definition); 3285 // If this is a redefinition, recover by making this 3286 // struct be anonymous, which will make any later 3287 // references get the previous definition. 3288 Name = 0; 3289 PrevDecl = 0; 3290 Invalid = true; 3291 } else { 3292 // If the type is currently being defined, complain 3293 // about a nested redefinition. 3294 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3295 if (Tag->isBeingDefined()) { 3296 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3297 Diag(PrevTagDecl->getLocation(), 3298 diag::note_previous_definition); 3299 Name = 0; 3300 PrevDecl = 0; 3301 Invalid = true; 3302 } 3303 } 3304 3305 // Okay, this is definition of a previously declared or referenced 3306 // tag PrevDecl. We're going to create a new Decl for it. 3307 } 3308 } 3309 // If we get here we have (another) forward declaration or we 3310 // have a definition. Just create a new decl. 3311 } else { 3312 // If we get here, this is a definition of a new tag type in a nested 3313 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3314 // new decl/type. We set PrevDecl to NULL so that the entities 3315 // have distinct types. 3316 PrevDecl = 0; 3317 } 3318 // If we get here, we're going to create a new Decl. If PrevDecl 3319 // is non-NULL, it's a definition of the tag declared by 3320 // PrevDecl. If it's NULL, we have a new definition. 3321 } else { 3322 // PrevDecl is a namespace, template, or anything else 3323 // that lives in the IDNS_Tag identifier namespace. 3324 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3325 // The tag name clashes with a namespace name, issue an error and 3326 // recover by making this tag be anonymous. 3327 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3328 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3329 Name = 0; 3330 PrevDecl = 0; 3331 Invalid = true; 3332 } else { 3333 // The existing declaration isn't relevant to us; we're in a 3334 // new scope, so clear out the previous declaration. 3335 PrevDecl = 0; 3336 } 3337 } 3338 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3339 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3340 // C.scope.pdecl]p5: 3341 // -- for an elaborated-type-specifier of the form 3342 // 3343 // class-key identifier 3344 // 3345 // if the elaborated-type-specifier is used in the 3346 // decl-specifier-seq or parameter-declaration-clause of a 3347 // function defined in namespace scope, the identifier is 3348 // declared as a class-name in the namespace that contains 3349 // the declaration; otherwise, except as a friend 3350 // declaration, the identifier is declared in the smallest 3351 // non-class, non-function-prototype scope that contains the 3352 // declaration. 3353 // 3354 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3355 // C structs and unions. 3356 // 3357 // GNU C also supports this behavior as part of its incomplete 3358 // enum types extension, while GNU C++ does not. 3359 // 3360 // Find the context where we'll be declaring the tag. 3361 // FIXME: We would like to maintain the current DeclContext as the 3362 // lexical context, 3363 while (SearchDC->isRecord()) 3364 SearchDC = SearchDC->getParent(); 3365 3366 // Find the scope where we'll be declaring the tag. 3367 while (S->isClassScope() || 3368 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3369 ((S->getFlags() & Scope::DeclScope) == 0) || 3370 (S->getEntity() && 3371 ((DeclContext *)S->getEntity())->isTransparentContext())) 3372 S = S->getParent(); 3373 } 3374 3375CreateNewDecl: 3376 3377 // If there is an identifier, use the location of the identifier as the 3378 // location of the decl, otherwise use the location of the struct/union 3379 // keyword. 3380 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3381 3382 // Otherwise, create a new declaration. If there is a previous 3383 // declaration of the same entity, the two will be linked via 3384 // PrevDecl. 3385 TagDecl *New; 3386 3387 if (Kind == TagDecl::TK_enum) { 3388 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3389 // enum X { A, B, C } D; D should chain to X. 3390 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3391 cast_or_null<EnumDecl>(PrevDecl)); 3392 // If this is an undefined enum, warn. 3393 if (TK != TK_Definition && !Invalid) { 3394 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3395 : diag::ext_forward_ref_enum; 3396 Diag(Loc, DK); 3397 } 3398 } else { 3399 // struct/union/class 3400 3401 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3402 // struct X { int A; } D; D should chain to X. 3403 if (getLangOptions().CPlusPlus) 3404 // FIXME: Look for a way to use RecordDecl for simple structs. 3405 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3406 cast_or_null<CXXRecordDecl>(PrevDecl)); 3407 else 3408 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3409 cast_or_null<RecordDecl>(PrevDecl)); 3410 } 3411 3412 if (Kind != TagDecl::TK_enum) { 3413 // Handle #pragma pack: if the #pragma pack stack has non-default 3414 // alignment, make up a packed attribute for this decl. These 3415 // attributes are checked when the ASTContext lays out the 3416 // structure. 3417 // 3418 // It is important for implementing the correct semantics that this 3419 // happen here (in act on tag decl). The #pragma pack stack is 3420 // maintained as a result of parser callbacks which can occur at 3421 // many points during the parsing of a struct declaration (because 3422 // the #pragma tokens are effectively skipped over during the 3423 // parsing of the struct). 3424 if (unsigned Alignment = getPragmaPackAlignment()) 3425 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3426 } 3427 3428 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3429 // C++ [dcl.typedef]p3: 3430 // [...] Similarly, in a given scope, a class or enumeration 3431 // shall not be declared with the same name as a typedef-name 3432 // that is declared in that scope and refers to a type other 3433 // than the class or enumeration itself. 3434 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3435 TypedefDecl *PrevTypedef = 0; 3436 if (Lookup.getKind() == LookupResult::Found) 3437 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3438 3439 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3440 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3441 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3442 Diag(Loc, diag::err_tag_definition_of_typedef) 3443 << Context.getTypeDeclType(New) 3444 << PrevTypedef->getUnderlyingType(); 3445 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3446 Invalid = true; 3447 } 3448 } 3449 3450 if (Invalid) 3451 New->setInvalidDecl(); 3452 3453 if (Attr) 3454 ProcessDeclAttributeList(New, Attr); 3455 3456 // If we're declaring or defining a tag in function prototype scope 3457 // in C, note that this type can only be used within the function. 3458 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3459 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3460 3461 // Set the lexical context. If the tag has a C++ scope specifier, the 3462 // lexical context will be different from the semantic context. 3463 New->setLexicalDeclContext(CurContext); 3464 3465 // Set the access specifier. 3466 SetMemberAccessSpecifier(New, PrevDecl, AS); 3467 3468 if (TK == TK_Definition) 3469 New->startDefinition(); 3470 3471 // If this has an identifier, add it to the scope stack. 3472 if (Name) { 3473 S = getNonFieldDeclScope(S); 3474 PushOnScopeChains(New, S); 3475 } else { 3476 CurContext->addDecl(Context, New); 3477 } 3478 3479 return DeclPtrTy::make(New); 3480} 3481 3482void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3483 AdjustDeclIfTemplate(TagD); 3484 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3485 3486 // Enter the tag context. 3487 PushDeclContext(S, Tag); 3488 3489 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3490 FieldCollector->StartClass(); 3491 3492 if (Record->getIdentifier()) { 3493 // C++ [class]p2: 3494 // [...] The class-name is also inserted into the scope of the 3495 // class itself; this is known as the injected-class-name. For 3496 // purposes of access checking, the injected-class-name is treated 3497 // as if it were a public member name. 3498 CXXRecordDecl *InjectedClassName 3499 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3500 CurContext, Record->getLocation(), 3501 Record->getIdentifier(), Record); 3502 InjectedClassName->setImplicit(); 3503 InjectedClassName->setAccess(AS_public); 3504 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3505 InjectedClassName->setDescribedClassTemplate(Template); 3506 PushOnScopeChains(InjectedClassName, S); 3507 assert(InjectedClassName->isInjectedClassName() && 3508 "Broken injected-class-name"); 3509 } 3510 } 3511} 3512 3513void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3514 AdjustDeclIfTemplate(TagD); 3515 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3516 3517 if (isa<CXXRecordDecl>(Tag)) 3518 FieldCollector->FinishClass(); 3519 3520 // Exit this scope of this tag's definition. 3521 PopDeclContext(); 3522 3523 // Notify the consumer that we've defined a tag. 3524 Consumer.HandleTagDeclDefinition(Tag); 3525} 3526 3527bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3528 QualType FieldTy, const Expr *BitWidth) { 3529 // C99 6.7.2.1p4 - verify the field type. 3530 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3531 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3532 // Handle incomplete types with specific error. 3533 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3534 return true; 3535 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3536 << FieldName << FieldTy << BitWidth->getSourceRange(); 3537 } 3538 3539 // If the bit-width is type- or value-dependent, don't try to check 3540 // it now. 3541 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3542 return false; 3543 3544 llvm::APSInt Value; 3545 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3546 return true; 3547 3548 // Zero-width bitfield is ok for anonymous field. 3549 if (Value == 0 && FieldName) 3550 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3551 3552 if (Value.isSigned() && Value.isNegative()) 3553 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3554 << FieldName << Value.toString(10); 3555 3556 if (!FieldTy->isDependentType()) { 3557 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3558 // FIXME: We won't need the 0 size once we check that the field type is valid. 3559 if (TypeSize && Value.getZExtValue() > TypeSize) 3560 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3561 << FieldName << (unsigned)TypeSize; 3562 } 3563 3564 return false; 3565} 3566 3567/// ActOnField - Each field of a struct/union/class is passed into this in order 3568/// to create a FieldDecl object for it. 3569Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3570 SourceLocation DeclStart, 3571 Declarator &D, ExprTy *BitfieldWidth) { 3572 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3573 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3574 AS_public); 3575 return DeclPtrTy::make(Res); 3576} 3577 3578/// HandleField - Analyze a field of a C struct or a C++ data member. 3579/// 3580FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3581 SourceLocation DeclStart, 3582 Declarator &D, Expr *BitWidth, 3583 AccessSpecifier AS) { 3584 IdentifierInfo *II = D.getIdentifier(); 3585 SourceLocation Loc = DeclStart; 3586 if (II) Loc = D.getIdentifierLoc(); 3587 3588 QualType T = GetTypeForDeclarator(D, S); 3589 3590 if (getLangOptions().CPlusPlus) { 3591 CheckExtraCXXDefaultArguments(D); 3592 } 3593 3594 DiagnoseFunctionSpecifiers(D); 3595 3596 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3597 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3598 PrevDecl = 0; 3599 3600 FieldDecl *NewFD 3601 = CheckFieldDecl(II, T, Record, Loc, 3602 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3603 BitWidth, AS, PrevDecl, &D); 3604 if (NewFD->isInvalidDecl() && PrevDecl) { 3605 // Don't introduce NewFD into scope; there's already something 3606 // with the same name in the same scope. 3607 } else if (II) { 3608 PushOnScopeChains(NewFD, S); 3609 } else 3610 Record->addDecl(Context, NewFD); 3611 3612 return NewFD; 3613} 3614 3615/// \brief Build a new FieldDecl and check its well-formedness. 3616/// 3617/// This routine builds a new FieldDecl given the fields name, type, 3618/// record, etc. \p PrevDecl should refer to any previous declaration 3619/// with the same name and in the same scope as the field to be 3620/// created. 3621/// 3622/// \returns a new FieldDecl. 3623/// 3624/// \todo The Declarator argument is a hack. It will be removed once 3625FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3626 RecordDecl *Record, SourceLocation Loc, 3627 bool Mutable, Expr *BitWidth, 3628 AccessSpecifier AS, NamedDecl *PrevDecl, 3629 Declarator *D) { 3630 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3631 bool InvalidDecl = false; 3632 3633 // If we receive a broken type, recover by assuming 'int' and 3634 // marking this declaration as invalid. 3635 if (T.isNull()) { 3636 InvalidDecl = true; 3637 T = Context.IntTy; 3638 } 3639 3640 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3641 // than a variably modified type. 3642 if (T->isVariablyModifiedType()) { 3643 bool SizeIsNegative; 3644 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3645 SizeIsNegative); 3646 if (!FixedTy.isNull()) { 3647 Diag(Loc, diag::warn_illegal_constant_array_size); 3648 T = FixedTy; 3649 } else { 3650 if (SizeIsNegative) 3651 Diag(Loc, diag::err_typecheck_negative_array_size); 3652 else 3653 Diag(Loc, diag::err_typecheck_field_variable_size); 3654 T = Context.IntTy; 3655 InvalidDecl = true; 3656 } 3657 } 3658 3659 // Fields can not have abstract class types 3660 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3661 AbstractFieldType)) 3662 InvalidDecl = true; 3663 3664 // If this is declared as a bit-field, check the bit-field. 3665 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3666 InvalidDecl = true; 3667 DeleteExpr(BitWidth); 3668 BitWidth = 0; 3669 } 3670 3671 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3672 Mutable); 3673 3674 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3675 Diag(Loc, diag::err_duplicate_member) << II; 3676 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3677 NewFD->setInvalidDecl(); 3678 Record->setInvalidDecl(); 3679 } 3680 3681 if (getLangOptions().CPlusPlus && !T->isPODType()) 3682 cast<CXXRecordDecl>(Record)->setPOD(false); 3683 3684 // FIXME: We need to pass in the attributes given an AST 3685 // representation, not a parser representation. 3686 if (D) 3687 ProcessDeclAttributes(NewFD, *D); 3688 3689 if (T.isObjCGCWeak()) 3690 Diag(Loc, diag::warn_attribute_weak_on_field); 3691 3692 if (InvalidDecl) 3693 NewFD->setInvalidDecl(); 3694 3695 NewFD->setAccess(AS); 3696 3697 // C++ [dcl.init.aggr]p1: 3698 // An aggregate is an array or a class (clause 9) with [...] no 3699 // private or protected non-static data members (clause 11). 3700 // A POD must be an aggregate. 3701 if (getLangOptions().CPlusPlus && 3702 (AS == AS_private || AS == AS_protected)) { 3703 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3704 CXXRecord->setAggregate(false); 3705 CXXRecord->setPOD(false); 3706 } 3707 3708 return NewFD; 3709} 3710 3711/// TranslateIvarVisibility - Translate visibility from a token ID to an 3712/// AST enum value. 3713static ObjCIvarDecl::AccessControl 3714TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3715 switch (ivarVisibility) { 3716 default: assert(0 && "Unknown visitibility kind"); 3717 case tok::objc_private: return ObjCIvarDecl::Private; 3718 case tok::objc_public: return ObjCIvarDecl::Public; 3719 case tok::objc_protected: return ObjCIvarDecl::Protected; 3720 case tok::objc_package: return ObjCIvarDecl::Package; 3721 } 3722} 3723 3724/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3725/// in order to create an IvarDecl object for it. 3726Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3727 SourceLocation DeclStart, 3728 Declarator &D, ExprTy *BitfieldWidth, 3729 tok::ObjCKeywordKind Visibility) { 3730 3731 IdentifierInfo *II = D.getIdentifier(); 3732 Expr *BitWidth = (Expr*)BitfieldWidth; 3733 SourceLocation Loc = DeclStart; 3734 if (II) Loc = D.getIdentifierLoc(); 3735 3736 // FIXME: Unnamed fields can be handled in various different ways, for 3737 // example, unnamed unions inject all members into the struct namespace! 3738 3739 QualType T = GetTypeForDeclarator(D, S); 3740 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3741 bool InvalidDecl = false; 3742 3743 if (BitWidth) { 3744 // 6.7.2.1p3, 6.7.2.1p4 3745 if (VerifyBitField(Loc, II, T, BitWidth)) { 3746 InvalidDecl = true; 3747 DeleteExpr(BitWidth); 3748 BitWidth = 0; 3749 } 3750 } else { 3751 // Not a bitfield. 3752 3753 // validate II. 3754 3755 } 3756 3757 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3758 // than a variably modified type. 3759 if (T->isVariablyModifiedType()) { 3760 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3761 InvalidDecl = true; 3762 } 3763 3764 // Get the visibility (access control) for this ivar. 3765 ObjCIvarDecl::AccessControl ac = 3766 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3767 : ObjCIvarDecl::None; 3768 3769 // Construct the decl. 3770 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3771 (Expr *)BitfieldWidth); 3772 3773 if (II) { 3774 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3775 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3776 && !isa<TagDecl>(PrevDecl)) { 3777 Diag(Loc, diag::err_duplicate_member) << II; 3778 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3779 NewID->setInvalidDecl(); 3780 } 3781 } 3782 3783 // Process attributes attached to the ivar. 3784 ProcessDeclAttributes(NewID, D); 3785 3786 if (D.getInvalidType() || InvalidDecl) 3787 NewID->setInvalidDecl(); 3788 3789 if (II) { 3790 // FIXME: When interfaces are DeclContexts, we'll need to add 3791 // these to the interface. 3792 S->AddDecl(DeclPtrTy::make(NewID)); 3793 IdResolver.AddDecl(NewID); 3794 } 3795 3796 return DeclPtrTy::make(NewID); 3797} 3798 3799void Sema::ActOnFields(Scope* S, 3800 SourceLocation RecLoc, DeclPtrTy RecDecl, 3801 DeclPtrTy *Fields, unsigned NumFields, 3802 SourceLocation LBrac, SourceLocation RBrac, 3803 AttributeList *Attr) { 3804 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3805 assert(EnclosingDecl && "missing record or interface decl"); 3806 3807 // If the decl this is being inserted into is invalid, then it may be a 3808 // redeclaration or some other bogus case. Don't try to add fields to it. 3809 if (EnclosingDecl->isInvalidDecl()) { 3810 // FIXME: Deallocate fields? 3811 return; 3812 } 3813 3814 3815 // Verify that all the fields are okay. 3816 unsigned NumNamedMembers = 0; 3817 llvm::SmallVector<FieldDecl*, 32> RecFields; 3818 3819 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3820 for (unsigned i = 0; i != NumFields; ++i) { 3821 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3822 3823 // Get the type for the field. 3824 Type *FDTy = FD->getType().getTypePtr(); 3825 3826 if (!FD->isAnonymousStructOrUnion()) { 3827 // Remember all fields written by the user. 3828 RecFields.push_back(FD); 3829 } 3830 3831 // If the field is already invalid for some reason, don't emit more 3832 // diagnostics about it. 3833 if (FD->isInvalidDecl()) 3834 continue; 3835 3836 // C99 6.7.2.1p2: 3837 // A structure or union shall not contain a member with 3838 // incomplete or function type (hence, a structure shall not 3839 // contain an instance of itself, but may contain a pointer to 3840 // an instance of itself), except that the last member of a 3841 // structure with more than one named member may have incomplete 3842 // array type; such a structure (and any union containing, 3843 // possibly recursively, a member that is such a structure) 3844 // shall not be a member of a structure or an element of an 3845 // array. 3846 if (FDTy->isFunctionType()) { 3847 // Field declared as a function. 3848 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3849 << FD->getDeclName(); 3850 FD->setInvalidDecl(); 3851 EnclosingDecl->setInvalidDecl(); 3852 continue; 3853 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3854 Record && Record->isStruct()) { 3855 // Flexible array member. 3856 if (NumNamedMembers < 1) { 3857 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3858 << FD->getDeclName(); 3859 FD->setInvalidDecl(); 3860 EnclosingDecl->setInvalidDecl(); 3861 continue; 3862 } 3863 // Okay, we have a legal flexible array member at the end of the struct. 3864 if (Record) 3865 Record->setHasFlexibleArrayMember(true); 3866 } else if (!FDTy->isDependentType() && 3867 RequireCompleteType(FD->getLocation(), FD->getType(), 3868 diag::err_field_incomplete)) { 3869 // Incomplete type 3870 FD->setInvalidDecl(); 3871 EnclosingDecl->setInvalidDecl(); 3872 continue; 3873 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3874 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3875 // If this is a member of a union, then entire union becomes "flexible". 3876 if (Record && Record->isUnion()) { 3877 Record->setHasFlexibleArrayMember(true); 3878 } else { 3879 // If this is a struct/class and this is not the last element, reject 3880 // it. Note that GCC supports variable sized arrays in the middle of 3881 // structures. 3882 if (i != NumFields-1) 3883 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3884 << FD->getDeclName(); 3885 else { 3886 // We support flexible arrays at the end of structs in 3887 // other structs as an extension. 3888 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3889 << FD->getDeclName(); 3890 if (Record) 3891 Record->setHasFlexibleArrayMember(true); 3892 } 3893 } 3894 } 3895 } else if (FDTy->isObjCInterfaceType()) { 3896 /// A field cannot be an Objective-c object 3897 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3898 FD->setInvalidDecl(); 3899 EnclosingDecl->setInvalidDecl(); 3900 continue; 3901 } 3902 // Keep track of the number of named members. 3903 if (FD->getIdentifier()) 3904 ++NumNamedMembers; 3905 } 3906 3907 // Okay, we successfully defined 'Record'. 3908 if (Record) { 3909 Record->completeDefinition(Context); 3910 } else { 3911 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3912 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3913 ID->setIVarList(ClsFields, RecFields.size(), Context); 3914 ID->setLocEnd(RBrac); 3915 3916 // Must enforce the rule that ivars in the base classes may not be 3917 // duplicates. 3918 if (ID->getSuperClass()) { 3919 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3920 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3921 ObjCIvarDecl* Ivar = (*IVI); 3922 IdentifierInfo *II = Ivar->getIdentifier(); 3923 ObjCIvarDecl* prevIvar = 3924 ID->getSuperClass()->lookupInstanceVariable(Context, II); 3925 if (prevIvar) { 3926 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3927 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3928 } 3929 } 3930 } 3931 } else if (ObjCImplementationDecl *IMPDecl = 3932 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3933 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3934 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3935 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3936 } 3937 } 3938 3939 if (Attr) 3940 ProcessDeclAttributeList(Record, Attr); 3941} 3942 3943EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 3944 EnumConstantDecl *LastEnumConst, 3945 SourceLocation IdLoc, 3946 IdentifierInfo *Id, 3947 ExprArg val) { 3948 Expr *Val = (Expr *)val.get(); 3949 3950 llvm::APSInt EnumVal(32); 3951 QualType EltTy; 3952 if (Val && !Val->isTypeDependent()) { 3953 // Make sure to promote the operand type to int. 3954 UsualUnaryConversions(Val); 3955 if (Val != val.get()) { 3956 val.release(); 3957 val = Val; 3958 } 3959 3960 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3961 SourceLocation ExpLoc; 3962 if (!Val->isValueDependent() && 3963 VerifyIntegerConstantExpression(Val, &EnumVal)) { 3964 Val = 0; 3965 } else { 3966 EltTy = Val->getType(); 3967 } 3968 } 3969 3970 if (!Val) { 3971 if (LastEnumConst) { 3972 // Assign the last value + 1. 3973 EnumVal = LastEnumConst->getInitVal(); 3974 ++EnumVal; 3975 3976 // Check for overflow on increment. 3977 if (EnumVal < LastEnumConst->getInitVal()) 3978 Diag(IdLoc, diag::warn_enum_value_overflow); 3979 3980 EltTy = LastEnumConst->getType(); 3981 } else { 3982 // First value, set to zero. 3983 EltTy = Context.IntTy; 3984 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3985 } 3986 } 3987 3988 val.release(); 3989 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 3990 Val, EnumVal); 3991} 3992 3993 3994Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 3995 DeclPtrTy lastEnumConst, 3996 SourceLocation IdLoc, 3997 IdentifierInfo *Id, 3998 SourceLocation EqualLoc, ExprTy *val) { 3999 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4000 EnumConstantDecl *LastEnumConst = 4001 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4002 Expr *Val = static_cast<Expr*>(val); 4003 4004 // The scope passed in may not be a decl scope. Zip up the scope tree until 4005 // we find one that is. 4006 S = getNonFieldDeclScope(S); 4007 4008 // Verify that there isn't already something declared with this name in this 4009 // scope. 4010 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4011 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4012 // Maybe we will complain about the shadowed template parameter. 4013 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4014 // Just pretend that we didn't see the previous declaration. 4015 PrevDecl = 0; 4016 } 4017 4018 if (PrevDecl) { 4019 // When in C++, we may get a TagDecl with the same name; in this case the 4020 // enum constant will 'hide' the tag. 4021 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4022 "Received TagDecl when not in C++!"); 4023 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4024 if (isa<EnumConstantDecl>(PrevDecl)) 4025 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4026 else 4027 Diag(IdLoc, diag::err_redefinition) << Id; 4028 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4029 if (Val) Val->Destroy(Context); 4030 return DeclPtrTy(); 4031 } 4032 } 4033 4034 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4035 IdLoc, Id, Owned(Val)); 4036 4037 // Register this decl in the current scope stack. 4038 if (New) 4039 PushOnScopeChains(New, S); 4040 4041 return DeclPtrTy::make(New); 4042} 4043 4044// FIXME: For consistency with ActOnFields(), we should have the parser 4045// pass in the source location for the left/right braces. 4046void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4047 DeclPtrTy *Elements, unsigned NumElements) { 4048 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4049 QualType EnumType = Context.getTypeDeclType(Enum); 4050 4051 // TODO: If the result value doesn't fit in an int, it must be a long or long 4052 // long value. ISO C does not support this, but GCC does as an extension, 4053 // emit a warning. 4054 unsigned IntWidth = Context.Target.getIntWidth(); 4055 4056 // Verify that all the values are okay, compute the size of the values, and 4057 // reverse the list. 4058 unsigned NumNegativeBits = 0; 4059 unsigned NumPositiveBits = 0; 4060 4061 // Keep track of whether all elements have type int. 4062 bool AllElementsInt = true; 4063 4064 for (unsigned i = 0; i != NumElements; ++i) { 4065 EnumConstantDecl *ECD = 4066 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4067 if (!ECD) continue; // Already issued a diagnostic. 4068 4069 // If the enum value doesn't fit in an int, emit an extension warning. 4070 const llvm::APSInt &InitVal = ECD->getInitVal(); 4071 assert(InitVal.getBitWidth() >= IntWidth && 4072 "Should have promoted value to int"); 4073 if (InitVal.getBitWidth() > IntWidth) { 4074 llvm::APSInt V(InitVal); 4075 V.trunc(IntWidth); 4076 V.extend(InitVal.getBitWidth()); 4077 if (V != InitVal) 4078 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4079 << InitVal.toString(10); 4080 } 4081 4082 // Keep track of the size of positive and negative values. 4083 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4084 NumPositiveBits = std::max(NumPositiveBits, 4085 (unsigned)InitVal.getActiveBits()); 4086 else 4087 NumNegativeBits = std::max(NumNegativeBits, 4088 (unsigned)InitVal.getMinSignedBits()); 4089 4090 // Keep track of whether every enum element has type int (very commmon). 4091 if (AllElementsInt) 4092 AllElementsInt = ECD->getType() == Context.IntTy; 4093 } 4094 4095 // Figure out the type that should be used for this enum. 4096 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4097 QualType BestType; 4098 unsigned BestWidth; 4099 4100 if (NumNegativeBits) { 4101 // If there is a negative value, figure out the smallest integer type (of 4102 // int/long/longlong) that fits. 4103 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4104 BestType = Context.IntTy; 4105 BestWidth = IntWidth; 4106 } else { 4107 BestWidth = Context.Target.getLongWidth(); 4108 4109 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4110 BestType = Context.LongTy; 4111 else { 4112 BestWidth = Context.Target.getLongLongWidth(); 4113 4114 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4115 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4116 BestType = Context.LongLongTy; 4117 } 4118 } 4119 } else { 4120 // If there is no negative value, figure out which of uint, ulong, ulonglong 4121 // fits. 4122 if (NumPositiveBits <= IntWidth) { 4123 BestType = Context.UnsignedIntTy; 4124 BestWidth = IntWidth; 4125 } else if (NumPositiveBits <= 4126 (BestWidth = Context.Target.getLongWidth())) { 4127 BestType = Context.UnsignedLongTy; 4128 } else { 4129 BestWidth = Context.Target.getLongLongWidth(); 4130 assert(NumPositiveBits <= BestWidth && 4131 "How could an initializer get larger than ULL?"); 4132 BestType = Context.UnsignedLongLongTy; 4133 } 4134 } 4135 4136 // Loop over all of the enumerator constants, changing their types to match 4137 // the type of the enum if needed. 4138 for (unsigned i = 0; i != NumElements; ++i) { 4139 EnumConstantDecl *ECD = 4140 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4141 if (!ECD) continue; // Already issued a diagnostic. 4142 4143 // Standard C says the enumerators have int type, but we allow, as an 4144 // extension, the enumerators to be larger than int size. If each 4145 // enumerator value fits in an int, type it as an int, otherwise type it the 4146 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4147 // that X has type 'int', not 'unsigned'. 4148 if (ECD->getType() == Context.IntTy) { 4149 // Make sure the init value is signed. 4150 llvm::APSInt IV = ECD->getInitVal(); 4151 IV.setIsSigned(true); 4152 ECD->setInitVal(IV); 4153 4154 if (getLangOptions().CPlusPlus) 4155 // C++ [dcl.enum]p4: Following the closing brace of an 4156 // enum-specifier, each enumerator has the type of its 4157 // enumeration. 4158 ECD->setType(EnumType); 4159 continue; // Already int type. 4160 } 4161 4162 // Determine whether the value fits into an int. 4163 llvm::APSInt InitVal = ECD->getInitVal(); 4164 bool FitsInInt; 4165 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4166 FitsInInt = InitVal.getActiveBits() < IntWidth; 4167 else 4168 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4169 4170 // If it fits into an integer type, force it. Otherwise force it to match 4171 // the enum decl type. 4172 QualType NewTy; 4173 unsigned NewWidth; 4174 bool NewSign; 4175 if (FitsInInt) { 4176 NewTy = Context.IntTy; 4177 NewWidth = IntWidth; 4178 NewSign = true; 4179 } else if (ECD->getType() == BestType) { 4180 // Already the right type! 4181 if (getLangOptions().CPlusPlus) 4182 // C++ [dcl.enum]p4: Following the closing brace of an 4183 // enum-specifier, each enumerator has the type of its 4184 // enumeration. 4185 ECD->setType(EnumType); 4186 continue; 4187 } else { 4188 NewTy = BestType; 4189 NewWidth = BestWidth; 4190 NewSign = BestType->isSignedIntegerType(); 4191 } 4192 4193 // Adjust the APSInt value. 4194 InitVal.extOrTrunc(NewWidth); 4195 InitVal.setIsSigned(NewSign); 4196 ECD->setInitVal(InitVal); 4197 4198 // Adjust the Expr initializer and type. 4199 if (ECD->getInitExpr()) 4200 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4201 /*isLvalue=*/false)); 4202 if (getLangOptions().CPlusPlus) 4203 // C++ [dcl.enum]p4: Following the closing brace of an 4204 // enum-specifier, each enumerator has the type of its 4205 // enumeration. 4206 ECD->setType(EnumType); 4207 else 4208 ECD->setType(NewTy); 4209 } 4210 4211 Enum->completeDefinition(Context, BestType); 4212} 4213 4214Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4215 ExprArg expr) { 4216 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4217 4218 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4219 Loc, AsmString)); 4220} 4221 4222