SemaDecl.cpp revision df9bcd568c79779d92b2f8d04a24ca822c56523d
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 if (!IIDecl || 89 (*Res)->getLocation().getRawEncoding() < 90 IIDecl->getLocation().getRawEncoding()) 91 IIDecl = *Res; 92 } 93 } 94 95 if (!IIDecl) { 96 // None of the entities we found is a type, so there is no way 97 // to even assume that the result is a type. In this case, don't 98 // complain about the ambiguity. The parser will either try to 99 // perform this lookup again (e.g., as an object name), which 100 // will produce the ambiguity, or will complain that it expected 101 // a type name. 102 Result.Destroy(); 103 return 0; 104 } 105 106 // We found a type within the ambiguous lookup; diagnose the 107 // ambiguity and then return that type. This might be the right 108 // answer, or it might not be, but it suppresses any attempt to 109 // perform the name lookup again. 110 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 111 break; 112 } 113 114 case LookupResult::Found: 115 IIDecl = Result.getAsDecl(); 116 break; 117 } 118 119 if (IIDecl) { 120 QualType T; 121 122 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 123 // Check whether we can use this type 124 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 125 126 T = Context.getTypeDeclType(TD); 127 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 128 // Check whether we can use this interface. 129 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 130 131 T = Context.getObjCInterfaceType(IDecl); 132 } else 133 return 0; 134 135 if (SS) 136 T = getQualifiedNameType(*SS, T); 137 138 return T.getAsOpaquePtr(); 139 } 140 141 return 0; 142} 143 144/// isTagName() - This method is called *for error recovery purposes only* 145/// to determine if the specified name is a valid tag name ("struct foo"). If 146/// so, this returns the TST for the tag corresponding to it (TST_enum, 147/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 148/// where the user forgot to specify the tag. 149DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 150 // Do a tag name lookup in this scope. 151 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 152 if (R.getKind() == LookupResult::Found) 153 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 154 switch (TD->getTagKind()) { 155 case TagDecl::TK_struct: return DeclSpec::TST_struct; 156 case TagDecl::TK_union: return DeclSpec::TST_union; 157 case TagDecl::TK_class: return DeclSpec::TST_class; 158 case TagDecl::TK_enum: return DeclSpec::TST_enum; 159 } 160 } 161 162 return DeclSpec::TST_unspecified; 163} 164 165 166 167DeclContext *Sema::getContainingDC(DeclContext *DC) { 168 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 169 // A C++ out-of-line method will return to the file declaration context. 170 if (MD->isOutOfLineDefinition()) 171 return MD->getLexicalDeclContext(); 172 173 // A C++ inline method is parsed *after* the topmost class it was declared 174 // in is fully parsed (it's "complete"). 175 // The parsing of a C++ inline method happens at the declaration context of 176 // the topmost (non-nested) class it is lexically declared in. 177 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 178 DC = MD->getParent(); 179 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 180 DC = RD; 181 182 // Return the declaration context of the topmost class the inline method is 183 // declared in. 184 return DC; 185 } 186 187 if (isa<ObjCMethodDecl>(DC)) 188 return Context.getTranslationUnitDecl(); 189 190 return DC->getLexicalParent(); 191} 192 193void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 194 assert(getContainingDC(DC) == CurContext && 195 "The next DeclContext should be lexically contained in the current one."); 196 CurContext = DC; 197 S->setEntity(DC); 198} 199 200void Sema::PopDeclContext() { 201 assert(CurContext && "DeclContext imbalance!"); 202 203 CurContext = getContainingDC(CurContext); 204} 205 206/// \brief Determine whether we allow overloading of the function 207/// PrevDecl with another declaration. 208/// 209/// This routine determines whether overloading is possible, not 210/// whether some new function is actually an overload. It will return 211/// true in C++ (where we can always provide overloads) or, as an 212/// extension, in C when the previous function is already an 213/// overloaded function declaration or has the "overloadable" 214/// attribute. 215static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 216 if (Context.getLangOptions().CPlusPlus) 217 return true; 218 219 if (isa<OverloadedFunctionDecl>(PrevDecl)) 220 return true; 221 222 return PrevDecl->getAttr<OverloadableAttr>() != 0; 223} 224 225/// Add this decl to the scope shadowed decl chains. 226void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 227 // Move up the scope chain until we find the nearest enclosing 228 // non-transparent context. The declaration will be introduced into this 229 // scope. 230 while (S->getEntity() && 231 ((DeclContext *)S->getEntity())->isTransparentContext()) 232 S = S->getParent(); 233 234 S->AddDecl(DeclPtrTy::make(D)); 235 236 // Add scoped declarations into their context, so that they can be 237 // found later. Declarations without a context won't be inserted 238 // into any context. 239 CurContext->addDecl(Context, D); 240 241 // C++ [basic.scope]p4: 242 // -- exactly one declaration shall declare a class name or 243 // enumeration name that is not a typedef name and the other 244 // declarations shall all refer to the same object or 245 // enumerator, or all refer to functions and function templates; 246 // in this case the class name or enumeration name is hidden. 247 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 248 // We are pushing the name of a tag (enum or class). 249 if (CurContext->getLookupContext() 250 == TD->getDeclContext()->getLookupContext()) { 251 // We're pushing the tag into the current context, which might 252 // require some reshuffling in the identifier resolver. 253 IdentifierResolver::iterator 254 I = IdResolver.begin(TD->getDeclName()), 255 IEnd = IdResolver.end(); 256 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 257 NamedDecl *PrevDecl = *I; 258 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 259 PrevDecl = *I, ++I) { 260 if (TD->declarationReplaces(*I)) { 261 // This is a redeclaration. Remove it from the chain and 262 // break out, so that we'll add in the shadowed 263 // declaration. 264 S->RemoveDecl(DeclPtrTy::make(*I)); 265 if (PrevDecl == *I) { 266 IdResolver.RemoveDecl(*I); 267 IdResolver.AddDecl(TD); 268 return; 269 } else { 270 IdResolver.RemoveDecl(*I); 271 break; 272 } 273 } 274 } 275 276 // There is already a declaration with the same name in the same 277 // scope, which is not a tag declaration. It must be found 278 // before we find the new declaration, so insert the new 279 // declaration at the end of the chain. 280 IdResolver.AddShadowedDecl(TD, PrevDecl); 281 282 return; 283 } 284 } 285 } else if (isa<FunctionDecl>(D) && 286 AllowOverloadingOfFunction(D, Context)) { 287 // We are pushing the name of a function, which might be an 288 // overloaded name. 289 FunctionDecl *FD = cast<FunctionDecl>(D); 290 IdentifierResolver::iterator Redecl 291 = std::find_if(IdResolver.begin(FD->getDeclName()), 292 IdResolver.end(), 293 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 294 FD)); 295 if (Redecl != IdResolver.end() && 296 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 297 // There is already a declaration of a function on our 298 // IdResolver chain. Replace it with this declaration. 299 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 300 IdResolver.RemoveDecl(*Redecl); 301 } 302 } 303 304 IdResolver.AddDecl(D); 305} 306 307void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 308 if (S->decl_empty()) return; 309 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 310 "Scope shouldn't contain decls!"); 311 312 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 313 I != E; ++I) { 314 Decl *TmpD = (*I).getAs<Decl>(); 315 assert(TmpD && "This decl didn't get pushed??"); 316 317 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 318 NamedDecl *D = cast<NamedDecl>(TmpD); 319 320 if (!D->getDeclName()) continue; 321 322 // Remove this name from our lexical scope. 323 IdResolver.RemoveDecl(D); 324 } 325} 326 327/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 328/// return 0 if one not found. 329ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 330 // The third "scope" argument is 0 since we aren't enabling lazy built-in 331 // creation from this context. 332 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 333 334 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 335} 336 337/// getNonFieldDeclScope - Retrieves the innermost scope, starting 338/// from S, where a non-field would be declared. This routine copes 339/// with the difference between C and C++ scoping rules in structs and 340/// unions. For example, the following code is well-formed in C but 341/// ill-formed in C++: 342/// @code 343/// struct S6 { 344/// enum { BAR } e; 345/// }; 346/// 347/// void test_S6() { 348/// struct S6 a; 349/// a.e = BAR; 350/// } 351/// @endcode 352/// For the declaration of BAR, this routine will return a different 353/// scope. The scope S will be the scope of the unnamed enumeration 354/// within S6. In C++, this routine will return the scope associated 355/// with S6, because the enumeration's scope is a transparent 356/// context but structures can contain non-field names. In C, this 357/// routine will return the translation unit scope, since the 358/// enumeration's scope is a transparent context and structures cannot 359/// contain non-field names. 360Scope *Sema::getNonFieldDeclScope(Scope *S) { 361 while (((S->getFlags() & Scope::DeclScope) == 0) || 362 (S->getEntity() && 363 ((DeclContext *)S->getEntity())->isTransparentContext()) || 364 (S->isClassScope() && !getLangOptions().CPlusPlus)) 365 S = S->getParent(); 366 return S; 367} 368 369void Sema::InitBuiltinVaListType() { 370 if (!Context.getBuiltinVaListType().isNull()) 371 return; 372 373 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 374 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 375 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 376 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 377} 378 379/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 380/// file scope. lazily create a decl for it. ForRedeclaration is true 381/// if we're creating this built-in in anticipation of redeclaring the 382/// built-in. 383NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 384 Scope *S, bool ForRedeclaration, 385 SourceLocation Loc) { 386 Builtin::ID BID = (Builtin::ID)bid; 387 388 if (Context.BuiltinInfo.hasVAListUse(BID)) 389 InitBuiltinVaListType(); 390 391 Builtin::Context::GetBuiltinTypeError Error; 392 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 393 switch (Error) { 394 case Builtin::Context::GE_None: 395 // Okay 396 break; 397 398 case Builtin::Context::GE_Missing_FILE: 399 if (ForRedeclaration) 400 Diag(Loc, diag::err_implicit_decl_requires_stdio) 401 << Context.BuiltinInfo.GetName(BID); 402 return 0; 403 } 404 405 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 406 Diag(Loc, diag::ext_implicit_lib_function_decl) 407 << Context.BuiltinInfo.GetName(BID) 408 << R; 409 if (Context.BuiltinInfo.getHeaderName(BID) && 410 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 411 != Diagnostic::Ignored) 412 Diag(Loc, diag::note_please_include_header) 413 << Context.BuiltinInfo.getHeaderName(BID) 414 << Context.BuiltinInfo.GetName(BID); 415 } 416 417 FunctionDecl *New = FunctionDecl::Create(Context, 418 Context.getTranslationUnitDecl(), 419 Loc, II, R, 420 FunctionDecl::Extern, false, 421 /*hasPrototype=*/true); 422 New->setImplicit(); 423 424 // Create Decl objects for each parameter, adding them to the 425 // FunctionDecl. 426 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 427 llvm::SmallVector<ParmVarDecl*, 16> Params; 428 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 429 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 430 FT->getArgType(i), VarDecl::None, 0)); 431 New->setParams(Context, &Params[0], Params.size()); 432 } 433 434 AddKnownFunctionAttributes(New); 435 436 // TUScope is the translation-unit scope to insert this function into. 437 // FIXME: This is hideous. We need to teach PushOnScopeChains to 438 // relate Scopes to DeclContexts, and probably eliminate CurContext 439 // entirely, but we're not there yet. 440 DeclContext *SavedContext = CurContext; 441 CurContext = Context.getTranslationUnitDecl(); 442 PushOnScopeChains(New, TUScope); 443 CurContext = SavedContext; 444 return New; 445} 446 447/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 448/// everything from the standard library is defined. 449NamespaceDecl *Sema::GetStdNamespace() { 450 if (!StdNamespace) { 451 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 452 DeclContext *Global = Context.getTranslationUnitDecl(); 453 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 454 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 455 } 456 return StdNamespace; 457} 458 459/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 460/// same name and scope as a previous declaration 'Old'. Figure out 461/// how to resolve this situation, merging decls or emitting 462/// diagnostics as appropriate. Returns true if there was an error, 463/// false otherwise. 464/// 465bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 466 bool objc_types = false; 467 // Allow multiple definitions for ObjC built-in typedefs. 468 // FIXME: Verify the underlying types are equivalent! 469 if (getLangOptions().ObjC1) { 470 const IdentifierInfo *TypeID = New->getIdentifier(); 471 switch (TypeID->getLength()) { 472 default: break; 473 case 2: 474 if (!TypeID->isStr("id")) 475 break; 476 Context.setObjCIdType(New); 477 objc_types = true; 478 break; 479 case 5: 480 if (!TypeID->isStr("Class")) 481 break; 482 Context.setObjCClassType(New); 483 objc_types = true; 484 return false; 485 case 3: 486 if (!TypeID->isStr("SEL")) 487 break; 488 Context.setObjCSelType(New); 489 objc_types = true; 490 return false; 491 case 8: 492 if (!TypeID->isStr("Protocol")) 493 break; 494 Context.setObjCProtoType(New->getUnderlyingType()); 495 objc_types = true; 496 return false; 497 } 498 // Fall through - the typedef name was not a builtin type. 499 } 500 // Verify the old decl was also a type. 501 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 502 if (!Old) { 503 Diag(New->getLocation(), diag::err_redefinition_different_kind) 504 << New->getDeclName(); 505 if (!objc_types) 506 Diag(OldD->getLocation(), diag::note_previous_definition); 507 return true; 508 } 509 510 // Determine the "old" type we'll use for checking and diagnostics. 511 QualType OldType; 512 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 513 OldType = OldTypedef->getUnderlyingType(); 514 else 515 OldType = Context.getTypeDeclType(Old); 516 517 // If the typedef types are not identical, reject them in all languages and 518 // with any extensions enabled. 519 520 if (OldType != New->getUnderlyingType() && 521 Context.getCanonicalType(OldType) != 522 Context.getCanonicalType(New->getUnderlyingType())) { 523 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 524 << New->getUnderlyingType() << OldType; 525 if (!objc_types) 526 Diag(Old->getLocation(), diag::note_previous_definition); 527 return true; 528 } 529 if (objc_types) return false; 530 if (getLangOptions().Microsoft) return false; 531 532 // C++ [dcl.typedef]p2: 533 // In a given non-class scope, a typedef specifier can be used to 534 // redefine the name of any type declared in that scope to refer 535 // to the type to which it already refers. 536 if (getLangOptions().CPlusPlus) { 537 if (!isa<CXXRecordDecl>(CurContext)) 538 return false; 539 Diag(New->getLocation(), diag::err_redefinition) 540 << New->getDeclName(); 541 Diag(Old->getLocation(), diag::note_previous_definition); 542 return true; 543 } 544 545 // If we have a redefinition of a typedef in C, emit a warning. This warning 546 // is normally mapped to an error, but can be controlled with 547 // -Wtypedef-redefinition. 548 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 549 << New->getDeclName(); 550 Diag(Old->getLocation(), diag::note_previous_definition); 551 return false; 552} 553 554/// DeclhasAttr - returns true if decl Declaration already has the target 555/// attribute. 556static bool DeclHasAttr(const Decl *decl, const Attr *target) { 557 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 558 if (attr->getKind() == target->getKind()) 559 return true; 560 561 return false; 562} 563 564/// MergeAttributes - append attributes from the Old decl to the New one. 565static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 566 Attr *attr = const_cast<Attr*>(Old->getAttrs()); 567 568 while (attr) { 569 Attr *tmp = attr; 570 attr = attr->getNext(); 571 572 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 573 tmp->setInherited(true); 574 New->addAttr(tmp); 575 } else { 576 tmp->setNext(0); 577 tmp->Destroy(C); 578 } 579 } 580 581 Old->invalidateAttrs(); 582} 583 584/// Used in MergeFunctionDecl to keep track of function parameters in 585/// C. 586struct GNUCompatibleParamWarning { 587 ParmVarDecl *OldParm; 588 ParmVarDecl *NewParm; 589 QualType PromotedType; 590}; 591 592/// MergeFunctionDecl - We just parsed a function 'New' from 593/// declarator D which has the same name and scope as a previous 594/// declaration 'Old'. Figure out how to resolve this situation, 595/// merging decls or emitting diagnostics as appropriate. 596/// 597/// In C++, New and Old must be declarations that are not 598/// overloaded. Use IsOverload to determine whether New and Old are 599/// overloaded, and to select the Old declaration that New should be 600/// merged with. 601/// 602/// Returns true if there was an error, false otherwise. 603bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 604 assert(!isa<OverloadedFunctionDecl>(OldD) && 605 "Cannot merge with an overloaded function declaration"); 606 607 // Verify the old decl was also a function. 608 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 609 if (!Old) { 610 Diag(New->getLocation(), diag::err_redefinition_different_kind) 611 << New->getDeclName(); 612 Diag(OldD->getLocation(), diag::note_previous_definition); 613 return true; 614 } 615 616 // Determine whether the previous declaration was a definition, 617 // implicit declaration, or a declaration. 618 diag::kind PrevDiag; 619 if (Old->isThisDeclarationADefinition()) 620 PrevDiag = diag::note_previous_definition; 621 else if (Old->isImplicit()) 622 PrevDiag = diag::note_previous_implicit_declaration; 623 else 624 PrevDiag = diag::note_previous_declaration; 625 626 QualType OldQType = Context.getCanonicalType(Old->getType()); 627 QualType NewQType = Context.getCanonicalType(New->getType()); 628 629 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 630 New->getStorageClass() == FunctionDecl::Static && 631 Old->getStorageClass() != FunctionDecl::Static) { 632 Diag(New->getLocation(), diag::err_static_non_static) 633 << New; 634 Diag(Old->getLocation(), PrevDiag); 635 return true; 636 } 637 638 if (getLangOptions().CPlusPlus) { 639 // (C++98 13.1p2): 640 // Certain function declarations cannot be overloaded: 641 // -- Function declarations that differ only in the return type 642 // cannot be overloaded. 643 QualType OldReturnType 644 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 645 QualType NewReturnType 646 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 647 if (OldReturnType != NewReturnType) { 648 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 649 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 650 return true; 651 } 652 653 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 654 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 655 if (OldMethod && NewMethod && 656 OldMethod->getLexicalDeclContext() == 657 NewMethod->getLexicalDeclContext()) { 658 // -- Member function declarations with the same name and the 659 // same parameter types cannot be overloaded if any of them 660 // is a static member function declaration. 661 if (OldMethod->isStatic() || NewMethod->isStatic()) { 662 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 663 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 664 return true; 665 } 666 667 // C++ [class.mem]p1: 668 // [...] A member shall not be declared twice in the 669 // member-specification, except that a nested class or member 670 // class template can be declared and then later defined. 671 unsigned NewDiag; 672 if (isa<CXXConstructorDecl>(OldMethod)) 673 NewDiag = diag::err_constructor_redeclared; 674 else if (isa<CXXDestructorDecl>(NewMethod)) 675 NewDiag = diag::err_destructor_redeclared; 676 else if (isa<CXXConversionDecl>(NewMethod)) 677 NewDiag = diag::err_conv_function_redeclared; 678 else 679 NewDiag = diag::err_member_redeclared; 680 681 Diag(New->getLocation(), NewDiag); 682 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 683 } 684 685 // (C++98 8.3.5p3): 686 // All declarations for a function shall agree exactly in both the 687 // return type and the parameter-type-list. 688 if (OldQType == NewQType) 689 return MergeCompatibleFunctionDecls(New, Old); 690 691 // Fall through for conflicting redeclarations and redefinitions. 692 } 693 694 // C: Function types need to be compatible, not identical. This handles 695 // duplicate function decls like "void f(int); void f(enum X);" properly. 696 if (!getLangOptions().CPlusPlus && 697 Context.typesAreCompatible(OldQType, NewQType)) { 698 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 699 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 700 const FunctionProtoType *OldProto = 0; 701 if (isa<FunctionNoProtoType>(NewFuncType) && 702 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 703 // The old declaration provided a function prototype, but the 704 // new declaration does not. Merge in the prototype. 705 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 706 OldProto->arg_type_end()); 707 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 708 &ParamTypes[0], ParamTypes.size(), 709 OldProto->isVariadic(), 710 OldProto->getTypeQuals()); 711 New->setType(NewQType); 712 New->setInheritedPrototype(); 713 714 // Synthesize a parameter for each argument type. 715 llvm::SmallVector<ParmVarDecl*, 16> Params; 716 for (FunctionProtoType::arg_type_iterator 717 ParamType = OldProto->arg_type_begin(), 718 ParamEnd = OldProto->arg_type_end(); 719 ParamType != ParamEnd; ++ParamType) { 720 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 721 SourceLocation(), 0, 722 *ParamType, VarDecl::None, 723 0); 724 Param->setImplicit(); 725 Params.push_back(Param); 726 } 727 728 New->setParams(Context, &Params[0], Params.size()); 729 } 730 731 return MergeCompatibleFunctionDecls(New, Old); 732 } 733 734 // GNU C permits a K&R definition to follow a prototype declaration 735 // if the declared types of the parameters in the K&R definition 736 // match the types in the prototype declaration, even when the 737 // promoted types of the parameters from the K&R definition differ 738 // from the types in the prototype. GCC then keeps the types from 739 // the prototype. 740 if (!getLangOptions().CPlusPlus && 741 !getLangOptions().NoExtensions && 742 Old->hasPrototype() && !New->hasPrototype() && 743 New->getType()->getAsFunctionProtoType() && 744 Old->getNumParams() == New->getNumParams()) { 745 llvm::SmallVector<QualType, 16> ArgTypes; 746 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 747 const FunctionProtoType *OldProto 748 = Old->getType()->getAsFunctionProtoType(); 749 const FunctionProtoType *NewProto 750 = New->getType()->getAsFunctionProtoType(); 751 752 // Determine whether this is the GNU C extension. 753 bool GNUCompatible = 754 Context.typesAreCompatible(OldProto->getResultType(), 755 NewProto->getResultType()) && 756 (OldProto->isVariadic() == NewProto->isVariadic()); 757 for (unsigned Idx = 0, End = Old->getNumParams(); 758 GNUCompatible && Idx != End; ++Idx) { 759 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 760 ParmVarDecl *NewParm = New->getParamDecl(Idx); 761 if (Context.typesAreCompatible(OldParm->getType(), 762 NewProto->getArgType(Idx))) { 763 ArgTypes.push_back(NewParm->getType()); 764 } else if (Context.typesAreCompatible(OldParm->getType(), 765 NewParm->getType())) { 766 GNUCompatibleParamWarning Warn 767 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 768 Warnings.push_back(Warn); 769 ArgTypes.push_back(NewParm->getType()); 770 } else 771 GNUCompatible = false; 772 } 773 774 if (GNUCompatible) { 775 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 776 Diag(Warnings[Warn].NewParm->getLocation(), 777 diag::ext_param_promoted_not_compatible_with_prototype) 778 << Warnings[Warn].PromotedType 779 << Warnings[Warn].OldParm->getType(); 780 Diag(Warnings[Warn].OldParm->getLocation(), 781 diag::note_previous_declaration); 782 } 783 784 New->setType(Context.getFunctionType(NewProto->getResultType(), 785 &ArgTypes[0], ArgTypes.size(), 786 NewProto->isVariadic(), 787 NewProto->getTypeQuals())); 788 return MergeCompatibleFunctionDecls(New, Old); 789 } 790 791 // Fall through to diagnose conflicting types. 792 } 793 794 // A function that has already been declared has been redeclared or defined 795 // with a different type- show appropriate diagnostic 796 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 797 // The user has declared a builtin function with an incompatible 798 // signature. 799 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 800 // The function the user is redeclaring is a library-defined 801 // function like 'malloc' or 'printf'. Warn about the 802 // redeclaration, then pretend that we don't know about this 803 // library built-in. 804 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 805 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 806 << Old << Old->getType(); 807 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 808 Old->setInvalidDecl(); 809 return false; 810 } 811 812 PrevDiag = diag::note_previous_builtin_declaration; 813 } 814 815 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 816 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 817 return true; 818} 819 820/// \brief Completes the merge of two function declarations that are 821/// known to be compatible. 822/// 823/// This routine handles the merging of attributes and other 824/// properties of function declarations form the old declaration to 825/// the new declaration, once we know that New is in fact a 826/// redeclaration of Old. 827/// 828/// \returns false 829bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 830 // Merge the attributes 831 MergeAttributes(New, Old, Context); 832 833 // Merge the storage class. 834 New->setStorageClass(Old->getStorageClass()); 835 836 // FIXME: need to implement inline semantics 837 838 // Merge "pure" flag. 839 if (Old->isPure()) 840 New->setPure(); 841 842 // Merge the "deleted" flag. 843 if (Old->isDeleted()) 844 New->setDeleted(); 845 846 if (getLangOptions().CPlusPlus) 847 return MergeCXXFunctionDecl(New, Old); 848 849 return false; 850} 851 852/// MergeVarDecl - We just parsed a variable 'New' which has the same name 853/// and scope as a previous declaration 'Old'. Figure out how to resolve this 854/// situation, merging decls or emitting diagnostics as appropriate. 855/// 856/// Tentative definition rules (C99 6.9.2p2) are checked by 857/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 858/// definitions here, since the initializer hasn't been attached. 859/// 860bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 861 // Verify the old decl was also a variable. 862 VarDecl *Old = dyn_cast<VarDecl>(OldD); 863 if (!Old) { 864 Diag(New->getLocation(), diag::err_redefinition_different_kind) 865 << New->getDeclName(); 866 Diag(OldD->getLocation(), diag::note_previous_definition); 867 return true; 868 } 869 870 MergeAttributes(New, Old, Context); 871 872 // Merge the types 873 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 874 if (MergedT.isNull()) { 875 Diag(New->getLocation(), diag::err_redefinition_different_type) 876 << New->getDeclName(); 877 Diag(Old->getLocation(), diag::note_previous_definition); 878 return true; 879 } 880 New->setType(MergedT); 881 882 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 883 if (New->getStorageClass() == VarDecl::Static && 884 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 885 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 886 Diag(Old->getLocation(), diag::note_previous_definition); 887 return true; 888 } 889 // C99 6.2.2p4: 890 // For an identifier declared with the storage-class specifier 891 // extern in a scope in which a prior declaration of that 892 // identifier is visible,23) if the prior declaration specifies 893 // internal or external linkage, the linkage of the identifier at 894 // the later declaration is the same as the linkage specified at 895 // the prior declaration. If no prior declaration is visible, or 896 // if the prior declaration specifies no linkage, then the 897 // identifier has external linkage. 898 if (New->hasExternalStorage() && Old->hasLinkage()) 899 /* Okay */; 900 else if (New->getStorageClass() != VarDecl::Static && 901 Old->getStorageClass() == VarDecl::Static) { 902 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 903 Diag(Old->getLocation(), diag::note_previous_definition); 904 return true; 905 } 906 907 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 908 909 // FIXME: The test for external storage here seems wrong? We still 910 // need to check for mismatches. 911 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 912 // Don't complain about out-of-line definitions of static members. 913 !(Old->getLexicalDeclContext()->isRecord() && 914 !New->getLexicalDeclContext()->isRecord())) { 915 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 916 Diag(Old->getLocation(), diag::note_previous_definition); 917 return true; 918 } 919 920 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 921 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 922 Diag(Old->getLocation(), diag::note_previous_definition); 923 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 924 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 925 Diag(Old->getLocation(), diag::note_previous_definition); 926 } 927 928 // Keep a chain of previous declarations. 929 New->setPreviousDeclaration(Old); 930 931 return false; 932} 933 934/// CheckParmsForFunctionDef - Check that the parameters of the given 935/// function are appropriate for the definition of a function. This 936/// takes care of any checks that cannot be performed on the 937/// declaration itself, e.g., that the types of each of the function 938/// parameters are complete. 939bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 940 bool HasInvalidParm = false; 941 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 942 ParmVarDecl *Param = FD->getParamDecl(p); 943 944 // C99 6.7.5.3p4: the parameters in a parameter type list in a 945 // function declarator that is part of a function definition of 946 // that function shall not have incomplete type. 947 // 948 // This is also C++ [dcl.fct]p6. 949 if (!Param->isInvalidDecl() && 950 RequireCompleteType(Param->getLocation(), Param->getType(), 951 diag::err_typecheck_decl_incomplete_type)) { 952 Param->setInvalidDecl(); 953 HasInvalidParm = true; 954 } 955 956 // C99 6.9.1p5: If the declarator includes a parameter type list, the 957 // declaration of each parameter shall include an identifier. 958 if (Param->getIdentifier() == 0 && 959 !Param->isImplicit() && 960 !getLangOptions().CPlusPlus) 961 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 962 } 963 964 return HasInvalidParm; 965} 966 967/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 968/// no declarator (e.g. "struct foo;") is parsed. 969Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 970 // FIXME: Error on auto/register at file scope 971 // FIXME: Error on inline/virtual/explicit 972 // FIXME: Error on invalid restrict 973 // FIXME: Warn on useless __thread 974 // FIXME: Warn on useless const/volatile 975 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 976 // FIXME: Warn on useless attributes 977 978 TagDecl *Tag = 0; 979 if (DS.getTypeSpecType() == DeclSpec::TST_class || 980 DS.getTypeSpecType() == DeclSpec::TST_struct || 981 DS.getTypeSpecType() == DeclSpec::TST_union || 982 DS.getTypeSpecType() == DeclSpec::TST_enum) 983 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 984 985 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 986 if (!Record->getDeclName() && Record->isDefinition() && 987 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 988 if (getLangOptions().CPlusPlus || 989 Record->getDeclContext()->isRecord()) 990 return BuildAnonymousStructOrUnion(S, DS, Record); 991 992 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 993 << DS.getSourceRange(); 994 } 995 996 // Microsoft allows unnamed struct/union fields. Don't complain 997 // about them. 998 // FIXME: Should we support Microsoft's extensions in this area? 999 if (Record->getDeclName() && getLangOptions().Microsoft) 1000 return DeclPtrTy::make(Tag); 1001 } 1002 1003 if (!DS.isMissingDeclaratorOk() && 1004 DS.getTypeSpecType() != DeclSpec::TST_error) { 1005 // Warn about typedefs of enums without names, since this is an 1006 // extension in both Microsoft an GNU. 1007 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1008 Tag && isa<EnumDecl>(Tag)) { 1009 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1010 << DS.getSourceRange(); 1011 return DeclPtrTy::make(Tag); 1012 } 1013 1014 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1015 << DS.getSourceRange(); 1016 return DeclPtrTy(); 1017 } 1018 1019 return DeclPtrTy::make(Tag); 1020} 1021 1022/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1023/// anonymous struct or union AnonRecord into the owning context Owner 1024/// and scope S. This routine will be invoked just after we realize 1025/// that an unnamed union or struct is actually an anonymous union or 1026/// struct, e.g., 1027/// 1028/// @code 1029/// union { 1030/// int i; 1031/// float f; 1032/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1033/// // f into the surrounding scope.x 1034/// @endcode 1035/// 1036/// This routine is recursive, injecting the names of nested anonymous 1037/// structs/unions into the owning context and scope as well. 1038bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1039 RecordDecl *AnonRecord) { 1040 bool Invalid = false; 1041 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1042 FEnd = AnonRecord->field_end(Context); 1043 F != FEnd; ++F) { 1044 if ((*F)->getDeclName()) { 1045 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1046 LookupOrdinaryName, true); 1047 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1048 // C++ [class.union]p2: 1049 // The names of the members of an anonymous union shall be 1050 // distinct from the names of any other entity in the 1051 // scope in which the anonymous union is declared. 1052 unsigned diagKind 1053 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1054 : diag::err_anonymous_struct_member_redecl; 1055 Diag((*F)->getLocation(), diagKind) 1056 << (*F)->getDeclName(); 1057 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1058 Invalid = true; 1059 } else { 1060 // C++ [class.union]p2: 1061 // For the purpose of name lookup, after the anonymous union 1062 // definition, the members of the anonymous union are 1063 // considered to have been defined in the scope in which the 1064 // anonymous union is declared. 1065 Owner->makeDeclVisibleInContext(Context, *F); 1066 S->AddDecl(DeclPtrTy::make(*F)); 1067 IdResolver.AddDecl(*F); 1068 } 1069 } else if (const RecordType *InnerRecordType 1070 = (*F)->getType()->getAsRecordType()) { 1071 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1072 if (InnerRecord->isAnonymousStructOrUnion()) 1073 Invalid = Invalid || 1074 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1075 } 1076 } 1077 1078 return Invalid; 1079} 1080 1081/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1082/// anonymous structure or union. Anonymous unions are a C++ feature 1083/// (C++ [class.union]) and a GNU C extension; anonymous structures 1084/// are a GNU C and GNU C++ extension. 1085Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1086 RecordDecl *Record) { 1087 DeclContext *Owner = Record->getDeclContext(); 1088 1089 // Diagnose whether this anonymous struct/union is an extension. 1090 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1091 Diag(Record->getLocation(), diag::ext_anonymous_union); 1092 else if (!Record->isUnion()) 1093 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1094 1095 // C and C++ require different kinds of checks for anonymous 1096 // structs/unions. 1097 bool Invalid = false; 1098 if (getLangOptions().CPlusPlus) { 1099 const char* PrevSpec = 0; 1100 // C++ [class.union]p3: 1101 // Anonymous unions declared in a named namespace or in the 1102 // global namespace shall be declared static. 1103 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1104 (isa<TranslationUnitDecl>(Owner) || 1105 (isa<NamespaceDecl>(Owner) && 1106 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1107 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1108 Invalid = true; 1109 1110 // Recover by adding 'static'. 1111 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1112 } 1113 // C++ [class.union]p3: 1114 // A storage class is not allowed in a declaration of an 1115 // anonymous union in a class scope. 1116 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1117 isa<RecordDecl>(Owner)) { 1118 Diag(DS.getStorageClassSpecLoc(), 1119 diag::err_anonymous_union_with_storage_spec); 1120 Invalid = true; 1121 1122 // Recover by removing the storage specifier. 1123 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1124 PrevSpec); 1125 } 1126 1127 // C++ [class.union]p2: 1128 // The member-specification of an anonymous union shall only 1129 // define non-static data members. [Note: nested types and 1130 // functions cannot be declared within an anonymous union. ] 1131 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1132 MemEnd = Record->decls_end(Context); 1133 Mem != MemEnd; ++Mem) { 1134 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1135 // C++ [class.union]p3: 1136 // An anonymous union shall not have private or protected 1137 // members (clause 11). 1138 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1139 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1140 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1141 Invalid = true; 1142 } 1143 } else if ((*Mem)->isImplicit()) { 1144 // Any implicit members are fine. 1145 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1146 // This is a type that showed up in an 1147 // elaborated-type-specifier inside the anonymous struct or 1148 // union, but which actually declares a type outside of the 1149 // anonymous struct or union. It's okay. 1150 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1151 if (!MemRecord->isAnonymousStructOrUnion() && 1152 MemRecord->getDeclName()) { 1153 // This is a nested type declaration. 1154 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1155 << (int)Record->isUnion(); 1156 Invalid = true; 1157 } 1158 } else { 1159 // We have something that isn't a non-static data 1160 // member. Complain about it. 1161 unsigned DK = diag::err_anonymous_record_bad_member; 1162 if (isa<TypeDecl>(*Mem)) 1163 DK = diag::err_anonymous_record_with_type; 1164 else if (isa<FunctionDecl>(*Mem)) 1165 DK = diag::err_anonymous_record_with_function; 1166 else if (isa<VarDecl>(*Mem)) 1167 DK = diag::err_anonymous_record_with_static; 1168 Diag((*Mem)->getLocation(), DK) 1169 << (int)Record->isUnion(); 1170 Invalid = true; 1171 } 1172 } 1173 } 1174 1175 if (!Record->isUnion() && !Owner->isRecord()) { 1176 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1177 << (int)getLangOptions().CPlusPlus; 1178 Invalid = true; 1179 } 1180 1181 // Create a declaration for this anonymous struct/union. 1182 NamedDecl *Anon = 0; 1183 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1184 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1185 /*IdentifierInfo=*/0, 1186 Context.getTypeDeclType(Record), 1187 /*BitWidth=*/0, /*Mutable=*/false); 1188 Anon->setAccess(AS_public); 1189 if (getLangOptions().CPlusPlus) 1190 FieldCollector->Add(cast<FieldDecl>(Anon)); 1191 } else { 1192 VarDecl::StorageClass SC; 1193 switch (DS.getStorageClassSpec()) { 1194 default: assert(0 && "Unknown storage class!"); 1195 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1196 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1197 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1198 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1199 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1200 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1201 case DeclSpec::SCS_mutable: 1202 // mutable can only appear on non-static class members, so it's always 1203 // an error here 1204 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1205 Invalid = true; 1206 SC = VarDecl::None; 1207 break; 1208 } 1209 1210 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1211 /*IdentifierInfo=*/0, 1212 Context.getTypeDeclType(Record), 1213 SC, DS.getSourceRange().getBegin()); 1214 } 1215 Anon->setImplicit(); 1216 1217 // Add the anonymous struct/union object to the current 1218 // context. We'll be referencing this object when we refer to one of 1219 // its members. 1220 Owner->addDecl(Context, Anon); 1221 1222 // Inject the members of the anonymous struct/union into the owning 1223 // context and into the identifier resolver chain for name lookup 1224 // purposes. 1225 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1226 Invalid = true; 1227 1228 // Mark this as an anonymous struct/union type. Note that we do not 1229 // do this until after we have already checked and injected the 1230 // members of this anonymous struct/union type, because otherwise 1231 // the members could be injected twice: once by DeclContext when it 1232 // builds its lookup table, and once by 1233 // InjectAnonymousStructOrUnionMembers. 1234 Record->setAnonymousStructOrUnion(true); 1235 1236 if (Invalid) 1237 Anon->setInvalidDecl(); 1238 1239 return DeclPtrTy::make(Anon); 1240} 1241 1242 1243/// GetNameForDeclarator - Determine the full declaration name for the 1244/// given Declarator. 1245DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1246 switch (D.getKind()) { 1247 case Declarator::DK_Abstract: 1248 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1249 return DeclarationName(); 1250 1251 case Declarator::DK_Normal: 1252 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1253 return DeclarationName(D.getIdentifier()); 1254 1255 case Declarator::DK_Constructor: { 1256 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1257 Ty = Context.getCanonicalType(Ty); 1258 return Context.DeclarationNames.getCXXConstructorName(Ty); 1259 } 1260 1261 case Declarator::DK_Destructor: { 1262 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1263 Ty = Context.getCanonicalType(Ty); 1264 return Context.DeclarationNames.getCXXDestructorName(Ty); 1265 } 1266 1267 case Declarator::DK_Conversion: { 1268 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1269 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1270 Ty = Context.getCanonicalType(Ty); 1271 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1272 } 1273 1274 case Declarator::DK_Operator: 1275 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1276 return Context.DeclarationNames.getCXXOperatorName( 1277 D.getOverloadedOperator()); 1278 } 1279 1280 assert(false && "Unknown name kind"); 1281 return DeclarationName(); 1282} 1283 1284/// isNearlyMatchingFunction - Determine whether the C++ functions 1285/// Declaration and Definition are "nearly" matching. This heuristic 1286/// is used to improve diagnostics in the case where an out-of-line 1287/// function definition doesn't match any declaration within 1288/// the class or namespace. 1289static bool isNearlyMatchingFunction(ASTContext &Context, 1290 FunctionDecl *Declaration, 1291 FunctionDecl *Definition) { 1292 if (Declaration->param_size() != Definition->param_size()) 1293 return false; 1294 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1295 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1296 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1297 1298 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1299 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1300 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1301 return false; 1302 } 1303 1304 return true; 1305} 1306 1307Sema::DeclPtrTy 1308Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1309 DeclarationName Name = GetNameForDeclarator(D); 1310 1311 // All of these full declarators require an identifier. If it doesn't have 1312 // one, the ParsedFreeStandingDeclSpec action should be used. 1313 if (!Name) { 1314 if (!D.getInvalidType()) // Reject this if we think it is valid. 1315 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1316 diag::err_declarator_need_ident) 1317 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1318 return DeclPtrTy(); 1319 } 1320 1321 // The scope passed in may not be a decl scope. Zip up the scope tree until 1322 // we find one that is. 1323 while ((S->getFlags() & Scope::DeclScope) == 0 || 1324 (S->getFlags() & Scope::TemplateParamScope) != 0) 1325 S = S->getParent(); 1326 1327 DeclContext *DC; 1328 NamedDecl *PrevDecl; 1329 NamedDecl *New; 1330 bool InvalidDecl = false; 1331 1332 QualType R = GetTypeForDeclarator(D, S); 1333 if (R.isNull()) { 1334 InvalidDecl = true; 1335 R = Context.IntTy; 1336 if (IsFunctionDefinition) // int(...) 1337 R = Context.getFunctionType(R, 0, 0, true, 0); 1338 1339 } 1340 1341 // See if this is a redefinition of a variable in the same scope. 1342 if (D.getCXXScopeSpec().isInvalid()) { 1343 DC = CurContext; 1344 PrevDecl = 0; 1345 InvalidDecl = true; 1346 } else if (!D.getCXXScopeSpec().isSet()) { 1347 LookupNameKind NameKind = LookupOrdinaryName; 1348 1349 // If the declaration we're planning to build will be a function 1350 // or object with linkage, then look for another declaration with 1351 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1352 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1353 /* Do nothing*/; 1354 else if (R->isFunctionType()) { 1355 if (CurContext->isFunctionOrMethod()) 1356 NameKind = LookupRedeclarationWithLinkage; 1357 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1358 NameKind = LookupRedeclarationWithLinkage; 1359 1360 DC = CurContext; 1361 PrevDecl = LookupName(S, Name, NameKind, true, 1362 D.getDeclSpec().getStorageClassSpec() != 1363 DeclSpec::SCS_static, 1364 D.getIdentifierLoc()); 1365 } else { // Something like "int foo::x;" 1366 DC = computeDeclContext(D.getCXXScopeSpec()); 1367 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1368 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1369 1370 // C++ 7.3.1.2p2: 1371 // Members (including explicit specializations of templates) of a named 1372 // namespace can also be defined outside that namespace by explicit 1373 // qualification of the name being defined, provided that the entity being 1374 // defined was already declared in the namespace and the definition appears 1375 // after the point of declaration in a namespace that encloses the 1376 // declarations namespace. 1377 // 1378 // Note that we only check the context at this point. We don't yet 1379 // have enough information to make sure that PrevDecl is actually 1380 // the declaration we want to match. For example, given: 1381 // 1382 // class X { 1383 // void f(); 1384 // void f(float); 1385 // }; 1386 // 1387 // void X::f(int) { } // ill-formed 1388 // 1389 // In this case, PrevDecl will point to the overload set 1390 // containing the two f's declared in X, but neither of them 1391 // matches. 1392 1393 // First check whether we named the global scope. 1394 if (isa<TranslationUnitDecl>(DC)) { 1395 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1396 << Name << D.getCXXScopeSpec().getRange(); 1397 } else if (!CurContext->Encloses(DC)) { 1398 // The qualifying scope doesn't enclose the original declaration. 1399 // Emit diagnostic based on current scope. 1400 SourceLocation L = D.getIdentifierLoc(); 1401 SourceRange R = D.getCXXScopeSpec().getRange(); 1402 if (isa<FunctionDecl>(CurContext)) 1403 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1404 else 1405 Diag(L, diag::err_invalid_declarator_scope) 1406 << Name << cast<NamedDecl>(DC) << R; 1407 InvalidDecl = true; 1408 } 1409 } 1410 1411 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1412 // Maybe we will complain about the shadowed template parameter. 1413 InvalidDecl = InvalidDecl 1414 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1415 // Just pretend that we didn't see the previous declaration. 1416 PrevDecl = 0; 1417 } 1418 1419 // In C++, the previous declaration we find might be a tag type 1420 // (class or enum). In this case, the new declaration will hide the 1421 // tag type. Note that this does does not apply if we're declaring a 1422 // typedef (C++ [dcl.typedef]p4). 1423 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1424 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1425 PrevDecl = 0; 1426 1427 bool Redeclaration = false; 1428 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1429 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, 1430 InvalidDecl, Redeclaration); 1431 } else if (R->isFunctionType()) { 1432 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1433 IsFunctionDefinition, InvalidDecl, 1434 Redeclaration); 1435 } else { 1436 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, 1437 InvalidDecl, Redeclaration); 1438 } 1439 1440 if (New == 0) 1441 return DeclPtrTy(); 1442 1443 // If this has an identifier and is not an invalid redeclaration, 1444 // add it to the scope stack. 1445 if (Name && !(Redeclaration && InvalidDecl)) 1446 PushOnScopeChains(New, S); 1447 // If any semantic error occurred, mark the decl as invalid. 1448 if (D.getInvalidType() || InvalidDecl) 1449 New->setInvalidDecl(); 1450 1451 return DeclPtrTy::make(New); 1452} 1453 1454/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1455/// types into constant array types in certain situations which would otherwise 1456/// be errors (for GCC compatibility). 1457static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1458 ASTContext &Context, 1459 bool &SizeIsNegative) { 1460 // This method tries to turn a variable array into a constant 1461 // array even when the size isn't an ICE. This is necessary 1462 // for compatibility with code that depends on gcc's buggy 1463 // constant expression folding, like struct {char x[(int)(char*)2];} 1464 SizeIsNegative = false; 1465 1466 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1467 QualType Pointee = PTy->getPointeeType(); 1468 QualType FixedType = 1469 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1470 if (FixedType.isNull()) return FixedType; 1471 FixedType = Context.getPointerType(FixedType); 1472 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1473 return FixedType; 1474 } 1475 1476 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1477 if (!VLATy) 1478 return QualType(); 1479 // FIXME: We should probably handle this case 1480 if (VLATy->getElementType()->isVariablyModifiedType()) 1481 return QualType(); 1482 1483 Expr::EvalResult EvalResult; 1484 if (!VLATy->getSizeExpr() || 1485 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1486 !EvalResult.Val.isInt()) 1487 return QualType(); 1488 1489 llvm::APSInt &Res = EvalResult.Val.getInt(); 1490 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1491 return Context.getConstantArrayType(VLATy->getElementType(), 1492 Res, ArrayType::Normal, 0); 1493 1494 SizeIsNegative = true; 1495 return QualType(); 1496} 1497 1498/// \brief Register the given locally-scoped external C declaration so 1499/// that it can be found later for redeclarations 1500void 1501Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1502 Scope *S) { 1503 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1504 "Decl is not a locally-scoped decl!"); 1505 // Note that we have a locally-scoped external with this name. 1506 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1507 1508 if (!PrevDecl) 1509 return; 1510 1511 // If there was a previous declaration of this variable, it may be 1512 // in our identifier chain. Update the identifier chain with the new 1513 // declaration. 1514 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1515 // The previous declaration was found on the identifer resolver 1516 // chain, so remove it from its scope. 1517 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1518 S = S->getParent(); 1519 1520 if (S) 1521 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1522 } 1523} 1524 1525/// \brief Diagnose function specifiers on a declaration of an identifier that 1526/// does not identify a function. 1527void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1528 // FIXME: We should probably indicate the identifier in question to avoid 1529 // confusion for constructs like "inline int a(), b;" 1530 if (D.getDeclSpec().isInlineSpecified()) 1531 Diag(D.getDeclSpec().getInlineSpecLoc(), 1532 diag::err_inline_non_function); 1533 1534 if (D.getDeclSpec().isVirtualSpecified()) 1535 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1536 diag::err_virtual_non_function); 1537 1538 if (D.getDeclSpec().isExplicitSpecified()) 1539 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1540 diag::err_explicit_non_function); 1541} 1542 1543NamedDecl* 1544Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1545 QualType R, Decl* PrevDecl, bool& InvalidDecl, 1546 bool &Redeclaration) { 1547 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1548 if (D.getCXXScopeSpec().isSet()) { 1549 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1550 << D.getCXXScopeSpec().getRange(); 1551 InvalidDecl = true; 1552 // Pretend we didn't see the scope specifier. 1553 DC = 0; 1554 } 1555 1556 if (getLangOptions().CPlusPlus) { 1557 // Check that there are no default arguments (C++ only). 1558 CheckExtraCXXDefaultArguments(D); 1559 } 1560 1561 DiagnoseFunctionSpecifiers(D); 1562 1563 if (D.getDeclSpec().isThreadSpecified()) 1564 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1565 1566 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1567 if (!NewTD) return 0; 1568 1569 // Handle attributes prior to checking for duplicates in MergeVarDecl 1570 ProcessDeclAttributes(NewTD, D); 1571 // Merge the decl with the existing one if appropriate. If the decl is 1572 // in an outer scope, it isn't the same thing. 1573 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1574 Redeclaration = true; 1575 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1576 InvalidDecl = true; 1577 } 1578 1579 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1580 // then it shall have block scope. 1581 QualType T = NewTD->getUnderlyingType(); 1582 if (T->isVariablyModifiedType()) { 1583 CurFunctionNeedsScopeChecking = true; 1584 1585 if (S->getFnParent() == 0) { 1586 bool SizeIsNegative; 1587 QualType FixedTy = 1588 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1589 if (!FixedTy.isNull()) { 1590 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1591 NewTD->setUnderlyingType(FixedTy); 1592 } else { 1593 if (SizeIsNegative) 1594 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1595 else if (T->isVariableArrayType()) 1596 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1597 else 1598 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1599 InvalidDecl = true; 1600 } 1601 } 1602 } 1603 return NewTD; 1604} 1605 1606/// \brief Determines whether the given declaration is an out-of-scope 1607/// previous declaration. 1608/// 1609/// This routine should be invoked when name lookup has found a 1610/// previous declaration (PrevDecl) that is not in the scope where a 1611/// new declaration by the same name is being introduced. If the new 1612/// declaration occurs in a local scope, previous declarations with 1613/// linkage may still be considered previous declarations (C99 1614/// 6.2.2p4-5, C++ [basic.link]p6). 1615/// 1616/// \param PrevDecl the previous declaration found by name 1617/// lookup 1618/// 1619/// \param DC the context in which the new declaration is being 1620/// declared. 1621/// 1622/// \returns true if PrevDecl is an out-of-scope previous declaration 1623/// for a new delcaration with the same name. 1624static bool 1625isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1626 ASTContext &Context) { 1627 if (!PrevDecl) 1628 return 0; 1629 1630 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1631 // case we need to check each of the overloaded functions. 1632 if (!PrevDecl->hasLinkage()) 1633 return false; 1634 1635 if (Context.getLangOptions().CPlusPlus) { 1636 // C++ [basic.link]p6: 1637 // If there is a visible declaration of an entity with linkage 1638 // having the same name and type, ignoring entities declared 1639 // outside the innermost enclosing namespace scope, the block 1640 // scope declaration declares that same entity and receives the 1641 // linkage of the previous declaration. 1642 DeclContext *OuterContext = DC->getLookupContext(); 1643 if (!OuterContext->isFunctionOrMethod()) 1644 // This rule only applies to block-scope declarations. 1645 return false; 1646 else { 1647 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1648 if (PrevOuterContext->isRecord()) 1649 // We found a member function: ignore it. 1650 return false; 1651 else { 1652 // Find the innermost enclosing namespace for the new and 1653 // previous declarations. 1654 while (!OuterContext->isFileContext()) 1655 OuterContext = OuterContext->getParent(); 1656 while (!PrevOuterContext->isFileContext()) 1657 PrevOuterContext = PrevOuterContext->getParent(); 1658 1659 // The previous declaration is in a different namespace, so it 1660 // isn't the same function. 1661 if (OuterContext->getPrimaryContext() != 1662 PrevOuterContext->getPrimaryContext()) 1663 return false; 1664 } 1665 } 1666 } 1667 1668 return true; 1669} 1670 1671NamedDecl* 1672Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1673 QualType R,NamedDecl* PrevDecl, bool& InvalidDecl, 1674 bool &Redeclaration) { 1675 DeclarationName Name = GetNameForDeclarator(D); 1676 1677 // Check that there are no default arguments (C++ only). 1678 if (getLangOptions().CPlusPlus) 1679 CheckExtraCXXDefaultArguments(D); 1680 1681 VarDecl *NewVD; 1682 VarDecl::StorageClass SC; 1683 switch (D.getDeclSpec().getStorageClassSpec()) { 1684 default: assert(0 && "Unknown storage class!"); 1685 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1686 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1687 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1688 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1689 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1690 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1691 case DeclSpec::SCS_mutable: 1692 // mutable can only appear on non-static class members, so it's always 1693 // an error here 1694 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1695 InvalidDecl = true; 1696 SC = VarDecl::None; 1697 break; 1698 } 1699 1700 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1701 if (!II) { 1702 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1703 << Name.getAsString(); 1704 return 0; 1705 } 1706 1707 DiagnoseFunctionSpecifiers(D); 1708 1709 if (!DC->isRecord() && S->getFnParent() == 0) { 1710 // C99 6.9p2: The storage-class specifiers auto and register shall not 1711 // appear in the declaration specifiers in an external declaration. 1712 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1713 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1714 InvalidDecl = true; 1715 } 1716 } 1717 if (DC->isRecord() && !CurContext->isRecord()) { 1718 // This is an out-of-line definition of a static data member. 1719 if (SC == VarDecl::Static) { 1720 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1721 diag::err_static_out_of_line) 1722 << CodeModificationHint::CreateRemoval( 1723 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1724 } else if (SC == VarDecl::None) 1725 SC = VarDecl::Static; 1726 } 1727 1728 // The variable can not 1729 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1730 II, R, SC, 1731 // FIXME: Move to DeclGroup... 1732 D.getDeclSpec().getSourceRange().getBegin()); 1733 1734 if (D.getDeclSpec().isThreadSpecified()) { 1735 if (NewVD->hasLocalStorage()) 1736 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1737 else if (!Context.Target.isTLSSupported()) 1738 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1739 else 1740 NewVD->setThreadSpecified(true); 1741 } 1742 1743 // Set the lexical context. If the declarator has a C++ scope specifier, the 1744 // lexical context will be different from the semantic context. 1745 NewVD->setLexicalDeclContext(CurContext); 1746 1747 // Handle attributes prior to checking for duplicates in MergeVarDecl 1748 ProcessDeclAttributes(NewVD, D); 1749 1750 // Handle GNU asm-label extension (encoded as an attribute). 1751 if (Expr *E = (Expr*) D.getAsmLabel()) { 1752 // The parser guarantees this is a string. 1753 StringLiteral *SE = cast<StringLiteral>(E); 1754 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1755 SE->getByteLength()))); 1756 } 1757 1758 // If name lookup finds a previous declaration that is not in the 1759 // same scope as the new declaration, this may still be an 1760 // acceptable redeclaration. 1761 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1762 !(NewVD->hasLinkage() && 1763 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1764 PrevDecl = 0; 1765 1766 // Merge the decl with the existing one if appropriate. 1767 if (PrevDecl) { 1768 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1769 // The user tried to define a non-static data member 1770 // out-of-line (C++ [dcl.meaning]p1). 1771 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1772 << D.getCXXScopeSpec().getRange(); 1773 PrevDecl = 0; 1774 InvalidDecl = true; 1775 } 1776 } else if (D.getCXXScopeSpec().isSet()) { 1777 // No previous declaration in the qualifying scope. 1778 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1779 << Name << D.getCXXScopeSpec().getRange(); 1780 InvalidDecl = true; 1781 } 1782 1783 if (CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration)) 1784 InvalidDecl = true; 1785 1786 // If this is a locally-scoped extern C variable, update the map of 1787 // such variables. 1788 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1789 !InvalidDecl) 1790 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1791 1792 return NewVD; 1793} 1794 1795/// \brief Perform semantic checking on a newly-created variable 1796/// declaration. 1797/// 1798/// This routine performs all of the type-checking required for a 1799/// variable declaration once it has been build. It is used both to 1800/// check variables after they have been parsed and their declarators 1801/// have been translated into a declaration, and to check 1802/// 1803/// \returns true if an error was encountered, false otherwise. 1804bool Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1805 bool &Redeclaration) { 1806 bool Invalid = false; 1807 1808 QualType T = NewVD->getType(); 1809 1810 if (T->isObjCInterfaceType()) { 1811 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1812 Invalid = true; 1813 } 1814 1815 // The variable can not have an abstract class type. 1816 if (RequireNonAbstractType(NewVD->getLocation(), T, 1817 diag::err_abstract_type_in_decl, 1818 AbstractVariableType)) 1819 Invalid = true; 1820 1821 // Emit an error if an address space was applied to decl with local storage. 1822 // This includes arrays of objects with address space qualifiers, but not 1823 // automatic variables that point to other address spaces. 1824 // ISO/IEC TR 18037 S5.1.2 1825 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1826 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1827 Invalid = true; 1828 } 1829 1830 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1831 && !NewVD->hasAttr<BlocksAttr>()) 1832 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1833 1834 bool isVM = T->isVariablyModifiedType(); 1835 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1836 CurFunctionNeedsScopeChecking = true; 1837 1838 if ((isVM && NewVD->hasLinkage()) || 1839 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1840 bool SizeIsNegative; 1841 QualType FixedTy = 1842 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1843 if (!FixedTy.isNull()) { 1844 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1845 NewVD->setType(FixedTy); 1846 } else if (T->isVariableArrayType()) { 1847 Invalid = true; 1848 1849 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1850 // FIXME: This won't give the correct result for 1851 // int a[10][n]; 1852 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1853 1854 if (NewVD->isFileVarDecl()) 1855 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1856 << SizeRange; 1857 else if (NewVD->getStorageClass() == VarDecl::Static) 1858 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1859 << SizeRange; 1860 else 1861 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1862 << SizeRange; 1863 } else { 1864 Invalid = true; 1865 1866 if (NewVD->isFileVarDecl()) 1867 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1868 else 1869 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1870 } 1871 } 1872 1873 if (!PrevDecl && NewVD->isExternC(Context)) { 1874 // Since we did not find anything by this name and we're declaring 1875 // an extern "C" variable, look for a non-visible extern "C" 1876 // declaration with the same name. 1877 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1878 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1879 if (Pos != LocallyScopedExternalDecls.end()) 1880 PrevDecl = Pos->second; 1881 } 1882 1883 if (!Invalid && T->isVoidType() && !NewVD->hasExternalStorage()) { 1884 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1885 << T; 1886 Invalid = true; 1887 } 1888 1889 if (PrevDecl) { 1890 Redeclaration = true; 1891 if (MergeVarDecl(NewVD, PrevDecl)) 1892 Invalid = true; 1893 } 1894 1895 return NewVD->isInvalidDecl() || Invalid; 1896} 1897 1898NamedDecl* 1899Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1900 QualType R, NamedDecl* PrevDecl, 1901 bool IsFunctionDefinition, 1902 bool& InvalidDecl, bool &Redeclaration) { 1903 assert(R.getTypePtr()->isFunctionType()); 1904 1905 DeclarationName Name = GetNameForDeclarator(D); 1906 FunctionDecl::StorageClass SC = FunctionDecl::None; 1907 switch (D.getDeclSpec().getStorageClassSpec()) { 1908 default: assert(0 && "Unknown storage class!"); 1909 case DeclSpec::SCS_auto: 1910 case DeclSpec::SCS_register: 1911 case DeclSpec::SCS_mutable: 1912 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1913 diag::err_typecheck_sclass_func); 1914 InvalidDecl = true; 1915 break; 1916 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1917 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1918 case DeclSpec::SCS_static: { 1919 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1920 // C99 6.7.1p5: 1921 // The declaration of an identifier for a function that has 1922 // block scope shall have no explicit storage-class specifier 1923 // other than extern 1924 // See also (C++ [dcl.stc]p4). 1925 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1926 diag::err_static_block_func); 1927 SC = FunctionDecl::None; 1928 } else 1929 SC = FunctionDecl::Static; 1930 break; 1931 } 1932 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1933 } 1934 1935 if (D.getDeclSpec().isThreadSpecified()) 1936 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1937 1938 bool isInline = D.getDeclSpec().isInlineSpecified(); 1939 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1940 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1941 1942 // Check that the return type is not an abstract class type. 1943 // For record types, this is done by the AbstractClassUsageDiagnoser once 1944 // the class has been completely parsed. 1945 if (!DC->isRecord() && 1946 RequireNonAbstractType(D.getIdentifierLoc(), 1947 R->getAsFunctionType()->getResultType(), 1948 diag::err_abstract_type_in_decl, 1949 AbstractReturnType)) 1950 InvalidDecl = true; 1951 1952 // Do not allow returning a objc interface by-value. 1953 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1954 Diag(D.getIdentifierLoc(), 1955 diag::err_object_cannot_be_passed_returned_by_value) << 0 1956 << R->getAsFunctionType()->getResultType(); 1957 InvalidDecl = true; 1958 } 1959 1960 bool isVirtualOkay = false; 1961 FunctionDecl *NewFD; 1962 if (D.getKind() == Declarator::DK_Constructor) { 1963 // This is a C++ constructor declaration. 1964 assert(DC->isRecord() && 1965 "Constructors can only be declared in a member context"); 1966 1967 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1968 1969 // Create the new declaration 1970 NewFD = CXXConstructorDecl::Create(Context, 1971 cast<CXXRecordDecl>(DC), 1972 D.getIdentifierLoc(), Name, R, 1973 isExplicit, isInline, 1974 /*isImplicitlyDeclared=*/false); 1975 1976 if (InvalidDecl) 1977 NewFD->setInvalidDecl(); 1978 } else if (D.getKind() == Declarator::DK_Destructor) { 1979 // This is a C++ destructor declaration. 1980 if (DC->isRecord()) { 1981 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1982 1983 NewFD = CXXDestructorDecl::Create(Context, 1984 cast<CXXRecordDecl>(DC), 1985 D.getIdentifierLoc(), Name, R, 1986 isInline, 1987 /*isImplicitlyDeclared=*/false); 1988 1989 if (InvalidDecl) 1990 NewFD->setInvalidDecl(); 1991 1992 isVirtualOkay = true; 1993 } else { 1994 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1995 1996 // Create a FunctionDecl to satisfy the function definition parsing 1997 // code path. 1998 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1999 Name, R, SC, isInline, 2000 /*hasPrototype=*/true, 2001 // FIXME: Move to DeclGroup... 2002 D.getDeclSpec().getSourceRange().getBegin()); 2003 InvalidDecl = true; 2004 NewFD->setInvalidDecl(); 2005 } 2006 } else if (D.getKind() == Declarator::DK_Conversion) { 2007 if (!DC->isRecord()) { 2008 Diag(D.getIdentifierLoc(), 2009 diag::err_conv_function_not_member); 2010 return 0; 2011 } else { 2012 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 2013 2014 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2015 D.getIdentifierLoc(), Name, R, 2016 isInline, isExplicit); 2017 2018 if (InvalidDecl) 2019 NewFD->setInvalidDecl(); 2020 2021 isVirtualOkay = true; 2022 } 2023 } else if (DC->isRecord()) { 2024 // This is a C++ method declaration. 2025 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2026 D.getIdentifierLoc(), Name, R, 2027 (SC == FunctionDecl::Static), isInline); 2028 2029 isVirtualOkay = (SC != FunctionDecl::Static); 2030 } else { 2031 // Determine whether the function was written with a 2032 // prototype. This true when: 2033 // - we're in C++ (where every function has a prototype), 2034 // - there is a prototype in the declarator, or 2035 // - the type R of the function is some kind of typedef or other reference 2036 // to a type name (which eventually refers to a function type). 2037 bool HasPrototype = 2038 getLangOptions().CPlusPlus || 2039 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2040 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2041 2042 NewFD = FunctionDecl::Create(Context, DC, 2043 D.getIdentifierLoc(), 2044 Name, R, SC, isInline, HasPrototype, 2045 // FIXME: Move to DeclGroup... 2046 D.getDeclSpec().getSourceRange().getBegin()); 2047 } 2048 2049 // Set the lexical context. If the declarator has a C++ 2050 // scope specifier, the lexical context will be different 2051 // from the semantic context. 2052 NewFD->setLexicalDeclContext(CurContext); 2053 2054 // C++ [dcl.fct.spec]p5: 2055 // The virtual specifier shall only be used in declarations of 2056 // nonstatic class member functions that appear within a 2057 // member-specification of a class declaration; see 10.3. 2058 // 2059 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2060 // function is also virtual if it overrides an already virtual 2061 // function. This is important to do here because it's part of the 2062 // declaration. 2063 if (isVirtual && !InvalidDecl) { 2064 if (!isVirtualOkay) { 2065 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2066 diag::err_virtual_non_function); 2067 } else if (!CurContext->isRecord()) { 2068 // 'virtual' was specified outside of the class. 2069 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2070 << CodeModificationHint::CreateRemoval( 2071 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2072 } else { 2073 // Okay: Add virtual to the method. 2074 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2075 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2076 CurClass->setAggregate(false); 2077 CurClass->setPOD(false); 2078 CurClass->setPolymorphic(true); 2079 CurClass->setHasTrivialConstructor(false); 2080 } 2081 } 2082 2083 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2084 !CurContext->isRecord()) { 2085 // C++ [class.static]p1: 2086 // A data or function member of a class may be declared static 2087 // in a class definition, in which case it is a static member of 2088 // the class. 2089 2090 // Complain about the 'static' specifier if it's on an out-of-line 2091 // member function definition. 2092 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2093 diag::err_static_out_of_line) 2094 << CodeModificationHint::CreateRemoval( 2095 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2096 } 2097 2098 // Handle GNU asm-label extension (encoded as an attribute). 2099 if (Expr *E = (Expr*) D.getAsmLabel()) { 2100 // The parser guarantees this is a string. 2101 StringLiteral *SE = cast<StringLiteral>(E); 2102 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2103 SE->getByteLength()))); 2104 } 2105 2106 // Copy the parameter declarations from the declarator D to 2107 // the function declaration NewFD, if they are available. 2108 if (D.getNumTypeObjects() > 0) { 2109 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2110 2111 // Create Decl objects for each parameter, adding them to the 2112 // FunctionDecl. 2113 llvm::SmallVector<ParmVarDecl*, 16> Params; 2114 2115 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2116 // function that takes no arguments, not a function that takes a 2117 // single void argument. 2118 // We let through "const void" here because Sema::GetTypeForDeclarator 2119 // already checks for that case. 2120 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2121 FTI.ArgInfo[0].Param && 2122 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2123 // empty arg list, don't push any params. 2124 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2125 2126 // In C++, the empty parameter-type-list must be spelled "void"; a 2127 // typedef of void is not permitted. 2128 if (getLangOptions().CPlusPlus && 2129 Param->getType().getUnqualifiedType() != Context.VoidTy) { 2130 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2131 } 2132 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2133 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2134 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2135 } 2136 2137 NewFD->setParams(Context, &Params[0], Params.size()); 2138 } else if (R->getAsTypedefType()) { 2139 // When we're declaring a function with a typedef, as in the 2140 // following example, we'll need to synthesize (unnamed) 2141 // parameters for use in the declaration. 2142 // 2143 // @code 2144 // typedef void fn(int); 2145 // fn f; 2146 // @endcode 2147 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 2148 if (!FT) { 2149 // This is a typedef of a function with no prototype, so we 2150 // don't need to do anything. 2151 } else if ((FT->getNumArgs() == 0) || 2152 (FT->getNumArgs() == 1 && !FT->isVariadic() && 2153 FT->getArgType(0)->isVoidType())) { 2154 // This is a zero-argument function. We don't need to do anything. 2155 } else { 2156 // Synthesize a parameter for each argument type. 2157 llvm::SmallVector<ParmVarDecl*, 16> Params; 2158 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 2159 ArgType != FT->arg_type_end(); ++ArgType) { 2160 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2161 SourceLocation(), 0, 2162 *ArgType, VarDecl::None, 2163 0); 2164 Param->setImplicit(); 2165 Params.push_back(Param); 2166 } 2167 2168 NewFD->setParams(Context, &Params[0], Params.size()); 2169 } 2170 } 2171 2172 // If name lookup finds a previous declaration that is not in the 2173 // same scope as the new declaration, this may still be an 2174 // acceptable redeclaration. 2175 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2176 !(NewFD->hasLinkage() && 2177 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2178 PrevDecl = 0; 2179 2180 // Perform semantic checking on the function declaration. 2181 bool OverloadableAttrRequired = false; // FIXME: HACK! 2182 if (CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2183 /*FIXME:*/OverloadableAttrRequired)) 2184 InvalidDecl = true; 2185 2186 if (D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2187 // An out-of-line member function declaration must also be a 2188 // definition (C++ [dcl.meaning]p1). 2189 if (!IsFunctionDefinition) { 2190 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2191 << D.getCXXScopeSpec().getRange(); 2192 InvalidDecl = true; 2193 } else if (!Redeclaration) { 2194 // The user tried to provide an out-of-line definition for a 2195 // function that is a member of a class or namespace, but there 2196 // was no such member function declared (C++ [class.mfct]p2, 2197 // C++ [namespace.memdef]p2). For example: 2198 // 2199 // class X { 2200 // void f() const; 2201 // }; 2202 // 2203 // void X::f() { } // ill-formed 2204 // 2205 // Complain about this problem, and attempt to suggest close 2206 // matches (e.g., those that differ only in cv-qualifiers and 2207 // whether the parameter types are references). 2208 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2209 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2210 InvalidDecl = true; 2211 2212 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2213 true); 2214 assert(!Prev.isAmbiguous() && 2215 "Cannot have an ambiguity in previous-declaration lookup"); 2216 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2217 Func != FuncEnd; ++Func) { 2218 if (isa<FunctionDecl>(*Func) && 2219 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2220 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2221 } 2222 2223 PrevDecl = 0; 2224 } 2225 } 2226 2227 // Handle attributes. We need to have merged decls when handling attributes 2228 // (for example to check for conflicts, etc). 2229 // FIXME: This needs to happen before we merge declarations. Then, 2230 // let attribute merging cope with attribute conflicts. 2231 ProcessDeclAttributes(NewFD, D); 2232 AddKnownFunctionAttributes(NewFD); 2233 2234 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2235 // If a function name is overloadable in C, then every function 2236 // with that name must be marked "overloadable". 2237 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2238 << Redeclaration << NewFD; 2239 if (PrevDecl) 2240 Diag(PrevDecl->getLocation(), 2241 diag::note_attribute_overloadable_prev_overload); 2242 NewFD->addAttr(::new (Context) OverloadableAttr()); 2243 } 2244 2245 // If this is a locally-scoped extern C function, update the 2246 // map of such names. 2247 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2248 && !InvalidDecl) 2249 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2250 2251 return NewFD; 2252} 2253 2254/// \brief Perform semantic checking of a new function declaration. 2255/// 2256/// Performs semantic analysis of the new function declaration 2257/// NewFD. This routine performs all semantic checking that does not 2258/// require the actual declarator involved in the declaration, and is 2259/// used both for the declaration of functions as they are parsed 2260/// (called via ActOnDeclarator) and for the declaration of functions 2261/// that have been instantiated via C++ template instantiation (called 2262/// via InstantiateDecl). 2263/// 2264/// \returns true if there was an error, false otherwise. 2265bool Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2266 bool &Redeclaration, 2267 bool &OverloadableAttrRequired) { 2268 bool InvalidDecl = false; 2269 2270 // Semantic checking for this function declaration (in isolation). 2271 if (getLangOptions().CPlusPlus) { 2272 // C++-specific checks. 2273 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 2274 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 2275 else if (isa<CXXDestructorDecl>(NewFD)) { 2276 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2277 Record->setUserDeclaredDestructor(true); 2278 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2279 // user-defined destructor. 2280 Record->setPOD(false); 2281 2282 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2283 // declared destructor. 2284 Record->setHasTrivialDestructor(false); 2285 } else if (CXXConversionDecl *Conversion 2286 = dyn_cast<CXXConversionDecl>(NewFD)) 2287 ActOnConversionDeclarator(Conversion); 2288 2289 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2290 if (NewFD->isOverloadedOperator() && 2291 CheckOverloadedOperatorDeclaration(NewFD)) 2292 InvalidDecl = true; 2293 } 2294 2295 // Check for a previous declaration of this name. 2296 if (!PrevDecl && NewFD->isExternC(Context)) { 2297 // Since we did not find anything by this name and we're declaring 2298 // an extern "C" function, look for a non-visible extern "C" 2299 // declaration with the same name. 2300 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2301 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2302 if (Pos != LocallyScopedExternalDecls.end()) 2303 PrevDecl = Pos->second; 2304 } 2305 2306 // Merge or overload the declaration with an existing declaration of 2307 // the same name, if appropriate. 2308 if (PrevDecl) { 2309 // Determine whether NewFD is an overload of PrevDecl or 2310 // a declaration that requires merging. If it's an overload, 2311 // there's no more work to do here; we'll just add the new 2312 // function to the scope. 2313 OverloadedFunctionDecl::function_iterator MatchedDecl; 2314 2315 if (!getLangOptions().CPlusPlus && 2316 AllowOverloadingOfFunction(PrevDecl, Context)) { 2317 OverloadableAttrRequired = true; 2318 2319 // Functions marked "overloadable" must have a prototype (that 2320 // we can't get through declaration merging). 2321 if (!NewFD->getType()->getAsFunctionProtoType()) { 2322 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2323 << NewFD; 2324 InvalidDecl = true; 2325 Redeclaration = true; 2326 2327 // Turn this into a variadic function with no parameters. 2328 QualType R = Context.getFunctionType( 2329 NewFD->getType()->getAsFunctionType()->getResultType(), 2330 0, 0, true, 0); 2331 NewFD->setType(R); 2332 } 2333 } 2334 2335 if (PrevDecl && 2336 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2337 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2338 Redeclaration = true; 2339 Decl *OldDecl = PrevDecl; 2340 2341 // If PrevDecl was an overloaded function, extract the 2342 // FunctionDecl that matched. 2343 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2344 OldDecl = *MatchedDecl; 2345 2346 // NewFD and OldDecl represent declarations that need to be 2347 // merged. 2348 if (MergeFunctionDecl(NewFD, OldDecl)) 2349 InvalidDecl = true; 2350 2351 if (!InvalidDecl) 2352 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2353 } 2354 } 2355 2356 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) { 2357 // In C++, check default arguments now that we have merged decls. Unless 2358 // the lexical context is the class, because in this case this is done 2359 // during delayed parsing anyway. 2360 CheckCXXDefaultArguments(NewFD); 2361 } 2362 2363 return InvalidDecl || NewFD->isInvalidDecl(); 2364} 2365 2366bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2367 // FIXME: Need strict checking. In C89, we need to check for 2368 // any assignment, increment, decrement, function-calls, or 2369 // commas outside of a sizeof. In C99, it's the same list, 2370 // except that the aforementioned are allowed in unevaluated 2371 // expressions. Everything else falls under the 2372 // "may accept other forms of constant expressions" exception. 2373 // (We never end up here for C++, so the constant expression 2374 // rules there don't matter.) 2375 if (Init->isConstantInitializer(Context)) 2376 return false; 2377 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2378 << Init->getSourceRange(); 2379 return true; 2380} 2381 2382void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2383 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2384} 2385 2386/// AddInitializerToDecl - Adds the initializer Init to the 2387/// declaration dcl. If DirectInit is true, this is C++ direct 2388/// initialization rather than copy initialization. 2389void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2390 Decl *RealDecl = dcl.getAs<Decl>(); 2391 // If there is no declaration, there was an error parsing it. Just ignore 2392 // the initializer. 2393 if (RealDecl == 0) 2394 return; 2395 2396 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2397 // With declarators parsed the way they are, the parser cannot 2398 // distinguish between a normal initializer and a pure-specifier. 2399 // Thus this grotesque test. 2400 IntegerLiteral *IL; 2401 Expr *Init = static_cast<Expr *>(init.get()); 2402 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2403 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2404 if (Method->isVirtual()) { 2405 Method->setPure(); 2406 2407 // A class is abstract if at least one function is pure virtual. 2408 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2409 } else if (!Method->isInvalidDecl()) { 2410 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2411 << Method->getDeclName() << Init->getSourceRange(); 2412 Method->setInvalidDecl(); 2413 } 2414 } else { 2415 Diag(Method->getLocation(), diag::err_member_function_initialization) 2416 << Method->getDeclName() << Init->getSourceRange(); 2417 Method->setInvalidDecl(); 2418 } 2419 return; 2420 } 2421 2422 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2423 if (!VDecl) { 2424 if (getLangOptions().CPlusPlus && 2425 RealDecl->getLexicalDeclContext()->isRecord() && 2426 isa<NamedDecl>(RealDecl)) 2427 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2428 << cast<NamedDecl>(RealDecl)->getDeclName(); 2429 else 2430 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2431 RealDecl->setInvalidDecl(); 2432 return; 2433 } 2434 2435 if (!VDecl->getType()->isArrayType() && 2436 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2437 diag::err_typecheck_decl_incomplete_type)) { 2438 RealDecl->setInvalidDecl(); 2439 return; 2440 } 2441 2442 const VarDecl *Def = 0; 2443 if (VDecl->getDefinition(Def)) { 2444 Diag(VDecl->getLocation(), diag::err_redefinition) 2445 << VDecl->getDeclName(); 2446 Diag(Def->getLocation(), diag::note_previous_definition); 2447 VDecl->setInvalidDecl(); 2448 return; 2449 } 2450 2451 // Take ownership of the expression, now that we're sure we have somewhere 2452 // to put it. 2453 Expr *Init = static_cast<Expr *>(init.release()); 2454 assert(Init && "missing initializer"); 2455 2456 // Get the decls type and save a reference for later, since 2457 // CheckInitializerTypes may change it. 2458 QualType DclT = VDecl->getType(), SavT = DclT; 2459 if (VDecl->isBlockVarDecl()) { 2460 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2461 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2462 VDecl->setInvalidDecl(); 2463 } else if (!VDecl->isInvalidDecl()) { 2464 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2465 VDecl->getDeclName(), DirectInit)) 2466 VDecl->setInvalidDecl(); 2467 2468 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2469 // Don't check invalid declarations to avoid emitting useless diagnostics. 2470 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2471 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2472 CheckForConstantInitializer(Init, DclT); 2473 } 2474 } 2475 } else if (VDecl->isStaticDataMember() && 2476 VDecl->getLexicalDeclContext()->isRecord()) { 2477 // This is an in-class initialization for a static data member, e.g., 2478 // 2479 // struct S { 2480 // static const int value = 17; 2481 // }; 2482 2483 // Attach the initializer 2484 VDecl->setInit(Init); 2485 2486 // C++ [class.mem]p4: 2487 // A member-declarator can contain a constant-initializer only 2488 // if it declares a static member (9.4) of const integral or 2489 // const enumeration type, see 9.4.2. 2490 QualType T = VDecl->getType(); 2491 if (!T->isDependentType() && 2492 (!Context.getCanonicalType(T).isConstQualified() || 2493 !T->isIntegralType())) { 2494 Diag(VDecl->getLocation(), diag::err_member_initialization) 2495 << VDecl->getDeclName() << Init->getSourceRange(); 2496 VDecl->setInvalidDecl(); 2497 } else { 2498 // C++ [class.static.data]p4: 2499 // If a static data member is of const integral or const 2500 // enumeration type, its declaration in the class definition 2501 // can specify a constant-initializer which shall be an 2502 // integral constant expression (5.19). 2503 if (!Init->isTypeDependent() && 2504 !Init->getType()->isIntegralType()) { 2505 // We have a non-dependent, non-integral or enumeration type. 2506 Diag(Init->getSourceRange().getBegin(), 2507 diag::err_in_class_initializer_non_integral_type) 2508 << Init->getType() << Init->getSourceRange(); 2509 VDecl->setInvalidDecl(); 2510 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2511 // Check whether the expression is a constant expression. 2512 llvm::APSInt Value; 2513 SourceLocation Loc; 2514 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2515 Diag(Loc, diag::err_in_class_initializer_non_constant) 2516 << Init->getSourceRange(); 2517 VDecl->setInvalidDecl(); 2518 } else if (!VDecl->getType()->isDependentType()) 2519 ImpCastExprToType(Init, VDecl->getType()); 2520 } 2521 } 2522 } else if (VDecl->isFileVarDecl()) { 2523 if (VDecl->getStorageClass() == VarDecl::Extern) 2524 Diag(VDecl->getLocation(), diag::warn_extern_init); 2525 if (!VDecl->isInvalidDecl()) 2526 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2527 VDecl->getDeclName(), DirectInit)) 2528 VDecl->setInvalidDecl(); 2529 2530 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2531 // Don't check invalid declarations to avoid emitting useless diagnostics. 2532 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2533 // C99 6.7.8p4. All file scoped initializers need to be constant. 2534 CheckForConstantInitializer(Init, DclT); 2535 } 2536 } 2537 // If the type changed, it means we had an incomplete type that was 2538 // completed by the initializer. For example: 2539 // int ary[] = { 1, 3, 5 }; 2540 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2541 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2542 VDecl->setType(DclT); 2543 Init->setType(DclT); 2544 } 2545 2546 // Attach the initializer to the decl. 2547 VDecl->setInit(Init); 2548 return; 2549} 2550 2551void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2552 Decl *RealDecl = dcl.getAs<Decl>(); 2553 2554 // If there is no declaration, there was an error parsing it. Just ignore it. 2555 if (RealDecl == 0) 2556 return; 2557 2558 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2559 QualType Type = Var->getType(); 2560 // C++ [dcl.init.ref]p3: 2561 // The initializer can be omitted for a reference only in a 2562 // parameter declaration (8.3.5), in the declaration of a 2563 // function return type, in the declaration of a class member 2564 // within its class declaration (9.2), and where the extern 2565 // specifier is explicitly used. 2566 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2567 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2568 << Var->getDeclName() 2569 << SourceRange(Var->getLocation(), Var->getLocation()); 2570 Var->setInvalidDecl(); 2571 return; 2572 } 2573 2574 // C++ [dcl.init]p9: 2575 // 2576 // If no initializer is specified for an object, and the object 2577 // is of (possibly cv-qualified) non-POD class type (or array 2578 // thereof), the object shall be default-initialized; if the 2579 // object is of const-qualified type, the underlying class type 2580 // shall have a user-declared default constructor. 2581 if (getLangOptions().CPlusPlus) { 2582 QualType InitType = Type; 2583 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2584 InitType = Array->getElementType(); 2585 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2586 CXXRecordDecl *RD = 2587 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2588 CXXConstructorDecl *Constructor = 0; 2589 if (!RequireCompleteType(Var->getLocation(), InitType, 2590 diag::err_invalid_incomplete_type_use)) 2591 Constructor 2592 = PerformInitializationByConstructor(InitType, 0, 0, 2593 Var->getLocation(), 2594 SourceRange(Var->getLocation(), 2595 Var->getLocation()), 2596 Var->getDeclName(), 2597 IK_Default); 2598 if (!Constructor) 2599 Var->setInvalidDecl(); 2600 else if (!RD->hasTrivialConstructor()) 2601 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2602 } 2603 } 2604 2605#if 0 2606 // FIXME: Temporarily disabled because we are not properly parsing 2607 // linkage specifications on declarations, e.g., 2608 // 2609 // extern "C" const CGPoint CGPointerZero; 2610 // 2611 // C++ [dcl.init]p9: 2612 // 2613 // If no initializer is specified for an object, and the 2614 // object is of (possibly cv-qualified) non-POD class type (or 2615 // array thereof), the object shall be default-initialized; if 2616 // the object is of const-qualified type, the underlying class 2617 // type shall have a user-declared default 2618 // constructor. Otherwise, if no initializer is specified for 2619 // an object, the object and its subobjects, if any, have an 2620 // indeterminate initial value; if the object or any of its 2621 // subobjects are of const-qualified type, the program is 2622 // ill-formed. 2623 // 2624 // This isn't technically an error in C, so we don't diagnose it. 2625 // 2626 // FIXME: Actually perform the POD/user-defined default 2627 // constructor check. 2628 if (getLangOptions().CPlusPlus && 2629 Context.getCanonicalType(Type).isConstQualified() && 2630 !Var->hasExternalStorage()) 2631 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2632 << Var->getName() 2633 << SourceRange(Var->getLocation(), Var->getLocation()); 2634#endif 2635 } 2636} 2637 2638Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2639 unsigned NumDecls) { 2640 llvm::SmallVector<Decl*, 8> Decls; 2641 2642 for (unsigned i = 0; i != NumDecls; ++i) 2643 if (Decl *D = Group[i].getAs<Decl>()) 2644 Decls.push_back(D); 2645 2646 // Perform semantic analysis that depends on having fully processed both 2647 // the declarator and initializer. 2648 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2649 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2650 if (!IDecl) 2651 continue; 2652 QualType T = IDecl->getType(); 2653 2654 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2655 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2656 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2657 if (!IDecl->isInvalidDecl() && 2658 RequireCompleteType(IDecl->getLocation(), T, 2659 diag::err_typecheck_decl_incomplete_type)) 2660 IDecl->setInvalidDecl(); 2661 } 2662 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2663 // object that has file scope without an initializer, and without a 2664 // storage-class specifier or with the storage-class specifier "static", 2665 // constitutes a tentative definition. Note: A tentative definition with 2666 // external linkage is valid (C99 6.2.2p5). 2667 if (IDecl->isTentativeDefinition(Context)) { 2668 QualType CheckType = T; 2669 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2670 2671 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2672 if (ArrayT) { 2673 CheckType = ArrayT->getElementType(); 2674 DiagID = diag::err_illegal_decl_array_incomplete_type; 2675 } 2676 2677 if (IDecl->isInvalidDecl()) { 2678 // Do nothing with invalid declarations 2679 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2680 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2681 // C99 6.9.2p3: If the declaration of an identifier for an object is 2682 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2683 // declared type shall not be an incomplete type. 2684 IDecl->setInvalidDecl(); 2685 } 2686 } 2687 } 2688 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2689 &Decls[0], Decls.size())); 2690} 2691 2692 2693/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2694/// to introduce parameters into function prototype scope. 2695Sema::DeclPtrTy 2696Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2697 const DeclSpec &DS = D.getDeclSpec(); 2698 2699 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2700 VarDecl::StorageClass StorageClass = VarDecl::None; 2701 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2702 StorageClass = VarDecl::Register; 2703 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2704 Diag(DS.getStorageClassSpecLoc(), 2705 diag::err_invalid_storage_class_in_func_decl); 2706 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2707 } 2708 2709 if (D.getDeclSpec().isThreadSpecified()) 2710 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2711 2712 DiagnoseFunctionSpecifiers(D); 2713 2714 // Check that there are no default arguments inside the type of this 2715 // parameter (C++ only). 2716 if (getLangOptions().CPlusPlus) 2717 CheckExtraCXXDefaultArguments(D); 2718 2719 // In this context, we *do not* check D.getInvalidType(). If the declarator 2720 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2721 // though it will not reflect the user specified type. 2722 QualType parmDeclType = GetTypeForDeclarator(D, S); 2723 if (parmDeclType.isNull()) { 2724 D.setInvalidType(true); 2725 parmDeclType = Context.IntTy; 2726 } 2727 2728 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2729 // Can this happen for params? We already checked that they don't conflict 2730 // among each other. Here they can only shadow globals, which is ok. 2731 IdentifierInfo *II = D.getIdentifier(); 2732 if (II) { 2733 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2734 if (PrevDecl->isTemplateParameter()) { 2735 // Maybe we will complain about the shadowed template parameter. 2736 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2737 // Just pretend that we didn't see the previous declaration. 2738 PrevDecl = 0; 2739 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2740 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2741 2742 // Recover by removing the name 2743 II = 0; 2744 D.SetIdentifier(0, D.getIdentifierLoc()); 2745 } 2746 } 2747 } 2748 2749 // Parameters can not be abstract class types. 2750 // For record types, this is done by the AbstractClassUsageDiagnoser once 2751 // the class has been completely parsed. 2752 if (!CurContext->isRecord() && 2753 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2754 diag::err_abstract_type_in_decl, 2755 AbstractParamType)) 2756 D.setInvalidType(true); 2757 2758 QualType T = adjustParameterType(parmDeclType); 2759 2760 ParmVarDecl *New; 2761 if (T == parmDeclType) // parameter type did not need adjustment 2762 New = ParmVarDecl::Create(Context, CurContext, 2763 D.getIdentifierLoc(), II, 2764 parmDeclType, StorageClass, 2765 0); 2766 else // keep track of both the adjusted and unadjusted types 2767 New = OriginalParmVarDecl::Create(Context, CurContext, 2768 D.getIdentifierLoc(), II, T, 2769 parmDeclType, StorageClass, 0); 2770 2771 if (D.getInvalidType()) 2772 New->setInvalidDecl(); 2773 2774 // Parameter declarators cannot be interface types. All ObjC objects are 2775 // passed by reference. 2776 if (T->isObjCInterfaceType()) { 2777 Diag(D.getIdentifierLoc(), 2778 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2779 New->setInvalidDecl(); 2780 } 2781 2782 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2783 if (D.getCXXScopeSpec().isSet()) { 2784 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2785 << D.getCXXScopeSpec().getRange(); 2786 New->setInvalidDecl(); 2787 } 2788 2789 // Add the parameter declaration into this scope. 2790 S->AddDecl(DeclPtrTy::make(New)); 2791 if (II) 2792 IdResolver.AddDecl(New); 2793 2794 ProcessDeclAttributes(New, D); 2795 return DeclPtrTy::make(New); 2796} 2797 2798void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2799 SourceLocation LocAfterDecls) { 2800 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2801 "Not a function declarator!"); 2802 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2803 2804 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2805 // for a K&R function. 2806 if (!FTI.hasPrototype) { 2807 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2808 --i; 2809 if (FTI.ArgInfo[i].Param == 0) { 2810 std::string Code = " int "; 2811 Code += FTI.ArgInfo[i].Ident->getName(); 2812 Code += ";\n"; 2813 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2814 << FTI.ArgInfo[i].Ident 2815 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2816 2817 // Implicitly declare the argument as type 'int' for lack of a better 2818 // type. 2819 DeclSpec DS; 2820 const char* PrevSpec; // unused 2821 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2822 PrevSpec); 2823 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2824 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2825 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2826 } 2827 } 2828 } 2829} 2830 2831Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2832 Declarator &D) { 2833 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2834 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2835 "Not a function declarator!"); 2836 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2837 2838 if (FTI.hasPrototype) { 2839 // FIXME: Diagnose arguments without names in C. 2840 } 2841 2842 Scope *ParentScope = FnBodyScope->getParent(); 2843 2844 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2845 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2846} 2847 2848Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2849 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2850 2851 CurFunctionNeedsScopeChecking = false; 2852 2853 // See if this is a redefinition. 2854 const FunctionDecl *Definition; 2855 if (FD->getBody(Context, Definition)) { 2856 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2857 Diag(Definition->getLocation(), diag::note_previous_definition); 2858 } 2859 2860 // Builtin functions cannot be defined. 2861 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2862 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2863 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2864 FD->setInvalidDecl(); 2865 } 2866 } 2867 2868 // The return type of a function definition must be complete 2869 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2870 QualType ResultType = FD->getResultType(); 2871 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2872 RequireCompleteType(FD->getLocation(), ResultType, 2873 diag::err_func_def_incomplete_result)) 2874 FD->setInvalidDecl(); 2875 2876 // GNU warning -Wmissing-prototypes: 2877 // Warn if a global function is defined without a previous 2878 // prototype declaration. This warning is issued even if the 2879 // definition itself provides a prototype. The aim is to detect 2880 // global functions that fail to be declared in header files. 2881 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2882 !FD->isMain()) { 2883 bool MissingPrototype = true; 2884 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2885 Prev; Prev = Prev->getPreviousDeclaration()) { 2886 // Ignore any declarations that occur in function or method 2887 // scope, because they aren't visible from the header. 2888 if (Prev->getDeclContext()->isFunctionOrMethod()) 2889 continue; 2890 2891 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2892 break; 2893 } 2894 2895 if (MissingPrototype) 2896 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2897 } 2898 2899 PushDeclContext(FnBodyScope, FD); 2900 2901 // Check the validity of our function parameters 2902 CheckParmsForFunctionDef(FD); 2903 2904 // Introduce our parameters into the function scope 2905 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2906 ParmVarDecl *Param = FD->getParamDecl(p); 2907 Param->setOwningFunction(FD); 2908 2909 // If this has an identifier, add it to the scope stack. 2910 if (Param->getIdentifier()) 2911 PushOnScopeChains(Param, FnBodyScope); 2912 } 2913 2914 // Checking attributes of current function definition 2915 // dllimport attribute. 2916 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2917 // dllimport attribute cannot be applied to definition. 2918 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2919 Diag(FD->getLocation(), 2920 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2921 << "dllimport"; 2922 FD->setInvalidDecl(); 2923 return DeclPtrTy::make(FD); 2924 } else { 2925 // If a symbol previously declared dllimport is later defined, the 2926 // attribute is ignored in subsequent references, and a warning is 2927 // emitted. 2928 Diag(FD->getLocation(), 2929 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2930 << FD->getNameAsCString() << "dllimport"; 2931 } 2932 } 2933 return DeclPtrTy::make(FD); 2934} 2935 2936 2937Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 2938 Decl *dcl = D.getAs<Decl>(); 2939 CompoundStmt *Body =cast<CompoundStmt>(static_cast<Stmt*>(BodyArg.release())); 2940 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2941 FD->setBody(Body); 2942 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2943 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2944 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2945 MD->setBody(Body); 2946 } else { 2947 Body->Destroy(Context); 2948 return DeclPtrTy(); 2949 } 2950 PopDeclContext(); 2951 // Verify and clean out per-function state. 2952 2953 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 2954 2955 // Check goto/label use. 2956 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2957 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 2958 LabelStmt *L = I->second; 2959 2960 // Verify that we have no forward references left. If so, there was a goto 2961 // or address of a label taken, but no definition of it. Label fwd 2962 // definitions are indicated with a null substmt. 2963 if (L->getSubStmt() != 0) 2964 continue; 2965 2966 // Emit error. 2967 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2968 2969 // At this point, we have gotos that use the bogus label. Stitch it into 2970 // the function body so that they aren't leaked and that the AST is well 2971 // formed. 2972 if (Body == 0) { 2973 // The whole function wasn't parsed correctly, just delete this. 2974 L->Destroy(Context); 2975 continue; 2976 } 2977 2978 // Otherwise, the body is valid: we want to stitch the label decl into the 2979 // function somewhere so that it is properly owned and so that the goto 2980 // has a valid target. Do this by creating a new compound stmt with the 2981 // label in it. 2982 2983 // Give the label a sub-statement. 2984 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2985 2986 std::vector<Stmt*> Elements(Body->body_begin(), Body->body_end()); 2987 Elements.push_back(L); 2988 Body->setStmts(Context, &Elements[0], Elements.size()); 2989 } 2990 FunctionLabelMap.clear(); 2991 2992 if (!Body) return D; 2993 2994 // Verify that that gotos and switch cases don't jump into scopes illegally. 2995 if (CurFunctionNeedsScopeChecking) 2996 DiagnoseInvalidJumps(Body); 2997 2998 return D; 2999} 3000 3001/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3002/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3003NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3004 IdentifierInfo &II, Scope *S) { 3005 // Before we produce a declaration for an implicitly defined 3006 // function, see whether there was a locally-scoped declaration of 3007 // this name as a function or variable. If so, use that 3008 // (non-visible) declaration, and complain about it. 3009 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3010 = LocallyScopedExternalDecls.find(&II); 3011 if (Pos != LocallyScopedExternalDecls.end()) { 3012 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3013 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3014 return Pos->second; 3015 } 3016 3017 // Extension in C99. Legal in C90, but warn about it. 3018 if (getLangOptions().C99) 3019 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3020 else 3021 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3022 3023 // FIXME: handle stuff like: 3024 // void foo() { extern float X(); } 3025 // void bar() { X(); } <-- implicit decl for X in another scope. 3026 3027 // Set a Declarator for the implicit definition: int foo(); 3028 const char *Dummy; 3029 DeclSpec DS; 3030 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3031 Error = Error; // Silence warning. 3032 assert(!Error && "Error setting up implicit decl!"); 3033 Declarator D(DS, Declarator::BlockContext); 3034 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3035 0, 0, 0, Loc, D), 3036 SourceLocation()); 3037 D.SetIdentifier(&II, Loc); 3038 3039 // Insert this function into translation-unit scope. 3040 3041 DeclContext *PrevDC = CurContext; 3042 CurContext = Context.getTranslationUnitDecl(); 3043 3044 FunctionDecl *FD = 3045 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3046 FD->setImplicit(); 3047 3048 CurContext = PrevDC; 3049 3050 AddKnownFunctionAttributes(FD); 3051 3052 return FD; 3053} 3054 3055/// \brief Adds any function attributes that we know a priori based on 3056/// the declaration of this function. 3057/// 3058/// These attributes can apply both to implicitly-declared builtins 3059/// (like __builtin___printf_chk) or to library-declared functions 3060/// like NSLog or printf. 3061void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3062 if (FD->isInvalidDecl()) 3063 return; 3064 3065 // If this is a built-in function, map its builtin attributes to 3066 // actual attributes. 3067 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3068 // Handle printf-formatting attributes. 3069 unsigned FormatIdx; 3070 bool HasVAListArg; 3071 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3072 if (!FD->getAttr<FormatAttr>()) 3073 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3074 FormatIdx + 2)); 3075 } 3076 3077 // Mark const if we don't care about errno and that is the only 3078 // thing preventing the function from being const. This allows 3079 // IRgen to use LLVM intrinsics for such functions. 3080 if (!getLangOptions().MathErrno && 3081 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3082 if (!FD->getAttr<ConstAttr>()) 3083 FD->addAttr(::new (Context) ConstAttr()); 3084 } 3085 } 3086 3087 IdentifierInfo *Name = FD->getIdentifier(); 3088 if (!Name) 3089 return; 3090 if ((!getLangOptions().CPlusPlus && 3091 FD->getDeclContext()->isTranslationUnit()) || 3092 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3093 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3094 LinkageSpecDecl::lang_c)) { 3095 // Okay: this could be a libc/libm/Objective-C function we know 3096 // about. 3097 } else 3098 return; 3099 3100 unsigned KnownID; 3101 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3102 if (KnownFunctionIDs[KnownID] == Name) 3103 break; 3104 3105 switch (KnownID) { 3106 case id_NSLog: 3107 case id_NSLogv: 3108 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3109 // FIXME: We known better than our headers. 3110 const_cast<FormatAttr *>(Format)->setType("printf"); 3111 } else 3112 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3113 break; 3114 3115 case id_asprintf: 3116 case id_vasprintf: 3117 if (!FD->getAttr<FormatAttr>()) 3118 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3119 break; 3120 3121 default: 3122 // Unknown function or known function without any attributes to 3123 // add. Do nothing. 3124 break; 3125 } 3126} 3127 3128TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3129 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3130 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3131 3132 // Scope manipulation handled by caller. 3133 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3134 D.getIdentifierLoc(), 3135 D.getIdentifier(), 3136 T); 3137 3138 if (TagType *TT = dyn_cast<TagType>(T)) { 3139 TagDecl *TD = TT->getDecl(); 3140 3141 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3142 // keep track of the TypedefDecl. 3143 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3144 TD->setTypedefForAnonDecl(NewTD); 3145 } 3146 3147 if (D.getInvalidType()) 3148 NewTD->setInvalidDecl(); 3149 return NewTD; 3150} 3151 3152/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3153/// former case, Name will be non-null. In the later case, Name will be null. 3154/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3155/// reference/declaration/definition of a tag. 3156Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3157 SourceLocation KWLoc, const CXXScopeSpec &SS, 3158 IdentifierInfo *Name, SourceLocation NameLoc, 3159 AttributeList *Attr, AccessSpecifier AS) { 3160 // If this is not a definition, it must have a name. 3161 assert((Name != 0 || TK == TK_Definition) && 3162 "Nameless record must be a definition!"); 3163 3164 TagDecl::TagKind Kind; 3165 switch (TagSpec) { 3166 default: assert(0 && "Unknown tag type!"); 3167 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3168 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3169 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3170 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3171 } 3172 3173 DeclContext *SearchDC = CurContext; 3174 DeclContext *DC = CurContext; 3175 NamedDecl *PrevDecl = 0; 3176 3177 bool Invalid = false; 3178 3179 if (Name && SS.isNotEmpty()) { 3180 // We have a nested-name tag ('struct foo::bar'). 3181 3182 // Check for invalid 'foo::'. 3183 if (SS.isInvalid()) { 3184 Name = 0; 3185 goto CreateNewDecl; 3186 } 3187 3188 // FIXME: RequireCompleteDeclContext(SS)? 3189 DC = computeDeclContext(SS); 3190 SearchDC = DC; 3191 // Look-up name inside 'foo::'. 3192 PrevDecl = dyn_cast_or_null<TagDecl>( 3193 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3194 3195 // A tag 'foo::bar' must already exist. 3196 if (PrevDecl == 0) { 3197 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3198 Name = 0; 3199 goto CreateNewDecl; 3200 } 3201 } else if (Name) { 3202 // If this is a named struct, check to see if there was a previous forward 3203 // declaration or definition. 3204 // FIXME: We're looking into outer scopes here, even when we 3205 // shouldn't be. Doing so can result in ambiguities that we 3206 // shouldn't be diagnosing. 3207 LookupResult R = LookupName(S, Name, LookupTagName, 3208 /*RedeclarationOnly=*/(TK != TK_Reference)); 3209 if (R.isAmbiguous()) { 3210 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3211 // FIXME: This is not best way to recover from case like: 3212 // 3213 // struct S s; 3214 // 3215 // causes needless "incomplete type" error later. 3216 Name = 0; 3217 PrevDecl = 0; 3218 Invalid = true; 3219 } 3220 else 3221 PrevDecl = R; 3222 3223 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3224 // FIXME: This makes sure that we ignore the contexts associated 3225 // with C structs, unions, and enums when looking for a matching 3226 // tag declaration or definition. See the similar lookup tweak 3227 // in Sema::LookupName; is there a better way to deal with this? 3228 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3229 SearchDC = SearchDC->getParent(); 3230 } 3231 } 3232 3233 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3234 // Maybe we will complain about the shadowed template parameter. 3235 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3236 // Just pretend that we didn't see the previous declaration. 3237 PrevDecl = 0; 3238 } 3239 3240 if (PrevDecl) { 3241 // Check whether the previous declaration is usable. 3242 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3243 3244 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3245 // If this is a use of a previous tag, or if the tag is already declared 3246 // in the same scope (so that the definition/declaration completes or 3247 // rementions the tag), reuse the decl. 3248 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3249 // Make sure that this wasn't declared as an enum and now used as a 3250 // struct or something similar. 3251 if (PrevTagDecl->getTagKind() != Kind) { 3252 bool SafeToContinue 3253 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3254 Kind != TagDecl::TK_enum); 3255 if (SafeToContinue) 3256 Diag(KWLoc, diag::err_use_with_wrong_tag) 3257 << Name 3258 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3259 PrevTagDecl->getKindName()); 3260 else 3261 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3262 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3263 3264 if (SafeToContinue) 3265 Kind = PrevTagDecl->getTagKind(); 3266 else { 3267 // Recover by making this an anonymous redefinition. 3268 Name = 0; 3269 PrevDecl = 0; 3270 Invalid = true; 3271 } 3272 } 3273 3274 if (!Invalid) { 3275 // If this is a use, just return the declaration we found. 3276 3277 // FIXME: In the future, return a variant or some other clue 3278 // for the consumer of this Decl to know it doesn't own it. 3279 // For our current ASTs this shouldn't be a problem, but will 3280 // need to be changed with DeclGroups. 3281 if (TK == TK_Reference) 3282 return DeclPtrTy::make(PrevDecl); 3283 3284 // Diagnose attempts to redefine a tag. 3285 if (TK == TK_Definition) { 3286 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3287 Diag(NameLoc, diag::err_redefinition) << Name; 3288 Diag(Def->getLocation(), diag::note_previous_definition); 3289 // If this is a redefinition, recover by making this 3290 // struct be anonymous, which will make any later 3291 // references get the previous definition. 3292 Name = 0; 3293 PrevDecl = 0; 3294 Invalid = true; 3295 } else { 3296 // If the type is currently being defined, complain 3297 // about a nested redefinition. 3298 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3299 if (Tag->isBeingDefined()) { 3300 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3301 Diag(PrevTagDecl->getLocation(), 3302 diag::note_previous_definition); 3303 Name = 0; 3304 PrevDecl = 0; 3305 Invalid = true; 3306 } 3307 } 3308 3309 // Okay, this is definition of a previously declared or referenced 3310 // tag PrevDecl. We're going to create a new Decl for it. 3311 } 3312 } 3313 // If we get here we have (another) forward declaration or we 3314 // have a definition. Just create a new decl. 3315 } else { 3316 // If we get here, this is a definition of a new tag type in a nested 3317 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3318 // new decl/type. We set PrevDecl to NULL so that the entities 3319 // have distinct types. 3320 PrevDecl = 0; 3321 } 3322 // If we get here, we're going to create a new Decl. If PrevDecl 3323 // is non-NULL, it's a definition of the tag declared by 3324 // PrevDecl. If it's NULL, we have a new definition. 3325 } else { 3326 // PrevDecl is a namespace, template, or anything else 3327 // that lives in the IDNS_Tag identifier namespace. 3328 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3329 // The tag name clashes with a namespace name, issue an error and 3330 // recover by making this tag be anonymous. 3331 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3332 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3333 Name = 0; 3334 PrevDecl = 0; 3335 Invalid = true; 3336 } else { 3337 // The existing declaration isn't relevant to us; we're in a 3338 // new scope, so clear out the previous declaration. 3339 PrevDecl = 0; 3340 } 3341 } 3342 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3343 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3344 // C.scope.pdecl]p5: 3345 // -- for an elaborated-type-specifier of the form 3346 // 3347 // class-key identifier 3348 // 3349 // if the elaborated-type-specifier is used in the 3350 // decl-specifier-seq or parameter-declaration-clause of a 3351 // function defined in namespace scope, the identifier is 3352 // declared as a class-name in the namespace that contains 3353 // the declaration; otherwise, except as a friend 3354 // declaration, the identifier is declared in the smallest 3355 // non-class, non-function-prototype scope that contains the 3356 // declaration. 3357 // 3358 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3359 // C structs and unions. 3360 // 3361 // GNU C also supports this behavior as part of its incomplete 3362 // enum types extension, while GNU C++ does not. 3363 // 3364 // Find the context where we'll be declaring the tag. 3365 // FIXME: We would like to maintain the current DeclContext as the 3366 // lexical context, 3367 while (SearchDC->isRecord()) 3368 SearchDC = SearchDC->getParent(); 3369 3370 // Find the scope where we'll be declaring the tag. 3371 while (S->isClassScope() || 3372 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3373 ((S->getFlags() & Scope::DeclScope) == 0) || 3374 (S->getEntity() && 3375 ((DeclContext *)S->getEntity())->isTransparentContext())) 3376 S = S->getParent(); 3377 } 3378 3379CreateNewDecl: 3380 3381 // If there is an identifier, use the location of the identifier as the 3382 // location of the decl, otherwise use the location of the struct/union 3383 // keyword. 3384 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3385 3386 // Otherwise, create a new declaration. If there is a previous 3387 // declaration of the same entity, the two will be linked via 3388 // PrevDecl. 3389 TagDecl *New; 3390 3391 if (Kind == TagDecl::TK_enum) { 3392 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3393 // enum X { A, B, C } D; D should chain to X. 3394 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3395 cast_or_null<EnumDecl>(PrevDecl)); 3396 // If this is an undefined enum, warn. 3397 if (TK != TK_Definition && !Invalid) { 3398 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3399 : diag::ext_forward_ref_enum; 3400 Diag(Loc, DK); 3401 } 3402 } else { 3403 // struct/union/class 3404 3405 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3406 // struct X { int A; } D; D should chain to X. 3407 if (getLangOptions().CPlusPlus) 3408 // FIXME: Look for a way to use RecordDecl for simple structs. 3409 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3410 cast_or_null<CXXRecordDecl>(PrevDecl)); 3411 else 3412 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3413 cast_or_null<RecordDecl>(PrevDecl)); 3414 } 3415 3416 if (Kind != TagDecl::TK_enum) { 3417 // Handle #pragma pack: if the #pragma pack stack has non-default 3418 // alignment, make up a packed attribute for this decl. These 3419 // attributes are checked when the ASTContext lays out the 3420 // structure. 3421 // 3422 // It is important for implementing the correct semantics that this 3423 // happen here (in act on tag decl). The #pragma pack stack is 3424 // maintained as a result of parser callbacks which can occur at 3425 // many points during the parsing of a struct declaration (because 3426 // the #pragma tokens are effectively skipped over during the 3427 // parsing of the struct). 3428 if (unsigned Alignment = getPragmaPackAlignment()) 3429 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3430 } 3431 3432 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3433 // C++ [dcl.typedef]p3: 3434 // [...] Similarly, in a given scope, a class or enumeration 3435 // shall not be declared with the same name as a typedef-name 3436 // that is declared in that scope and refers to a type other 3437 // than the class or enumeration itself. 3438 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3439 TypedefDecl *PrevTypedef = 0; 3440 if (Lookup.getKind() == LookupResult::Found) 3441 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3442 3443 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3444 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3445 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3446 Diag(Loc, diag::err_tag_definition_of_typedef) 3447 << Context.getTypeDeclType(New) 3448 << PrevTypedef->getUnderlyingType(); 3449 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3450 Invalid = true; 3451 } 3452 } 3453 3454 if (Invalid) 3455 New->setInvalidDecl(); 3456 3457 if (Attr) 3458 ProcessDeclAttributeList(New, Attr); 3459 3460 // If we're declaring or defining a tag in function prototype scope 3461 // in C, note that this type can only be used within the function. 3462 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3463 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3464 3465 // Set the lexical context. If the tag has a C++ scope specifier, the 3466 // lexical context will be different from the semantic context. 3467 New->setLexicalDeclContext(CurContext); 3468 3469 // Set the access specifier. 3470 SetMemberAccessSpecifier(New, PrevDecl, AS); 3471 3472 if (TK == TK_Definition) 3473 New->startDefinition(); 3474 3475 // If this has an identifier, add it to the scope stack. 3476 if (Name) { 3477 S = getNonFieldDeclScope(S); 3478 PushOnScopeChains(New, S); 3479 } else { 3480 CurContext->addDecl(Context, New); 3481 } 3482 3483 return DeclPtrTy::make(New); 3484} 3485 3486void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3487 AdjustDeclIfTemplate(TagD); 3488 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3489 3490 // Enter the tag context. 3491 PushDeclContext(S, Tag); 3492 3493 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3494 FieldCollector->StartClass(); 3495 3496 if (Record->getIdentifier()) { 3497 // C++ [class]p2: 3498 // [...] The class-name is also inserted into the scope of the 3499 // class itself; this is known as the injected-class-name. For 3500 // purposes of access checking, the injected-class-name is treated 3501 // as if it were a public member name. 3502 CXXRecordDecl *InjectedClassName 3503 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3504 CurContext, Record->getLocation(), 3505 Record->getIdentifier(), Record); 3506 InjectedClassName->setImplicit(); 3507 InjectedClassName->setAccess(AS_public); 3508 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3509 InjectedClassName->setDescribedClassTemplate(Template); 3510 PushOnScopeChains(InjectedClassName, S); 3511 assert(InjectedClassName->isInjectedClassName() && 3512 "Broken injected-class-name"); 3513 } 3514 } 3515} 3516 3517void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3518 AdjustDeclIfTemplate(TagD); 3519 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3520 3521 if (isa<CXXRecordDecl>(Tag)) 3522 FieldCollector->FinishClass(); 3523 3524 // Exit this scope of this tag's definition. 3525 PopDeclContext(); 3526 3527 // Notify the consumer that we've defined a tag. 3528 Consumer.HandleTagDeclDefinition(Tag); 3529} 3530 3531// Note that FieldName may be null for anonymous bitfields. 3532bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3533 QualType FieldTy, const Expr *BitWidth) { 3534 3535 // C99 6.7.2.1p4 - verify the field type. 3536 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3537 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3538 // Handle incomplete types with specific error. 3539 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3540 return true; 3541 if (FieldName) 3542 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3543 << FieldName << FieldTy << BitWidth->getSourceRange(); 3544 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3545 << FieldTy << BitWidth->getSourceRange(); 3546 } 3547 3548 // If the bit-width is type- or value-dependent, don't try to check 3549 // it now. 3550 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3551 return false; 3552 3553 llvm::APSInt Value; 3554 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3555 return true; 3556 3557 // Zero-width bitfield is ok for anonymous field. 3558 if (Value == 0 && FieldName) 3559 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3560 3561 if (Value.isSigned() && Value.isNegative()) { 3562 if (FieldName) 3563 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3564 << FieldName << Value.toString(10); 3565 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3566 << Value.toString(10); 3567 } 3568 3569 if (!FieldTy->isDependentType()) { 3570 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3571 if (Value.getZExtValue() > TypeSize) { 3572 if (FieldName) 3573 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3574 << FieldName << (unsigned)TypeSize; 3575 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3576 << (unsigned)TypeSize; 3577 } 3578 } 3579 3580 return false; 3581} 3582 3583/// ActOnField - Each field of a struct/union/class is passed into this in order 3584/// to create a FieldDecl object for it. 3585Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3586 SourceLocation DeclStart, 3587 Declarator &D, ExprTy *BitfieldWidth) { 3588 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3589 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3590 AS_public); 3591 return DeclPtrTy::make(Res); 3592} 3593 3594/// HandleField - Analyze a field of a C struct or a C++ data member. 3595/// 3596FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3597 SourceLocation DeclStart, 3598 Declarator &D, Expr *BitWidth, 3599 AccessSpecifier AS) { 3600 IdentifierInfo *II = D.getIdentifier(); 3601 SourceLocation Loc = DeclStart; 3602 if (II) Loc = D.getIdentifierLoc(); 3603 3604 QualType T = GetTypeForDeclarator(D, S); 3605 if (getLangOptions().CPlusPlus) 3606 CheckExtraCXXDefaultArguments(D); 3607 3608 DiagnoseFunctionSpecifiers(D); 3609 3610 if (D.getDeclSpec().isThreadSpecified()) 3611 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3612 3613 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3614 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3615 PrevDecl = 0; 3616 3617 FieldDecl *NewFD 3618 = CheckFieldDecl(II, T, Record, Loc, 3619 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3620 BitWidth, AS, PrevDecl, &D); 3621 if (NewFD->isInvalidDecl() && PrevDecl) { 3622 // Don't introduce NewFD into scope; there's already something 3623 // with the same name in the same scope. 3624 } else if (II) { 3625 PushOnScopeChains(NewFD, S); 3626 } else 3627 Record->addDecl(Context, NewFD); 3628 3629 return NewFD; 3630} 3631 3632/// \brief Build a new FieldDecl and check its well-formedness. 3633/// 3634/// This routine builds a new FieldDecl given the fields name, type, 3635/// record, etc. \p PrevDecl should refer to any previous declaration 3636/// with the same name and in the same scope as the field to be 3637/// created. 3638/// 3639/// \returns a new FieldDecl. 3640/// 3641/// \todo The Declarator argument is a hack. It will be removed once 3642FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3643 RecordDecl *Record, SourceLocation Loc, 3644 bool Mutable, Expr *BitWidth, 3645 AccessSpecifier AS, NamedDecl *PrevDecl, 3646 Declarator *D) { 3647 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3648 bool InvalidDecl = false; 3649 3650 // If we receive a broken type, recover by assuming 'int' and 3651 // marking this declaration as invalid. 3652 if (T.isNull()) { 3653 InvalidDecl = true; 3654 T = Context.IntTy; 3655 } 3656 3657 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3658 // than a variably modified type. 3659 if (T->isVariablyModifiedType()) { 3660 bool SizeIsNegative; 3661 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3662 SizeIsNegative); 3663 if (!FixedTy.isNull()) { 3664 Diag(Loc, diag::warn_illegal_constant_array_size); 3665 T = FixedTy; 3666 } else { 3667 if (SizeIsNegative) 3668 Diag(Loc, diag::err_typecheck_negative_array_size); 3669 else 3670 Diag(Loc, diag::err_typecheck_field_variable_size); 3671 T = Context.IntTy; 3672 InvalidDecl = true; 3673 } 3674 } 3675 3676 // Fields can not have abstract class types 3677 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3678 AbstractFieldType)) 3679 InvalidDecl = true; 3680 3681 // If this is declared as a bit-field, check the bit-field. 3682 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3683 InvalidDecl = true; 3684 DeleteExpr(BitWidth); 3685 BitWidth = 0; 3686 } 3687 3688 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3689 Mutable); 3690 3691 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3692 Diag(Loc, diag::err_duplicate_member) << II; 3693 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3694 NewFD->setInvalidDecl(); 3695 Record->setInvalidDecl(); 3696 } 3697 3698 if (getLangOptions().CPlusPlus && !T->isPODType()) 3699 cast<CXXRecordDecl>(Record)->setPOD(false); 3700 3701 // FIXME: We need to pass in the attributes given an AST 3702 // representation, not a parser representation. 3703 if (D) 3704 ProcessDeclAttributes(NewFD, *D); 3705 3706 if (T.isObjCGCWeak()) 3707 Diag(Loc, diag::warn_attribute_weak_on_field); 3708 3709 if (InvalidDecl) 3710 NewFD->setInvalidDecl(); 3711 3712 NewFD->setAccess(AS); 3713 3714 // C++ [dcl.init.aggr]p1: 3715 // An aggregate is an array or a class (clause 9) with [...] no 3716 // private or protected non-static data members (clause 11). 3717 // A POD must be an aggregate. 3718 if (getLangOptions().CPlusPlus && 3719 (AS == AS_private || AS == AS_protected)) { 3720 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3721 CXXRecord->setAggregate(false); 3722 CXXRecord->setPOD(false); 3723 } 3724 3725 return NewFD; 3726} 3727 3728/// TranslateIvarVisibility - Translate visibility from a token ID to an 3729/// AST enum value. 3730static ObjCIvarDecl::AccessControl 3731TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3732 switch (ivarVisibility) { 3733 default: assert(0 && "Unknown visitibility kind"); 3734 case tok::objc_private: return ObjCIvarDecl::Private; 3735 case tok::objc_public: return ObjCIvarDecl::Public; 3736 case tok::objc_protected: return ObjCIvarDecl::Protected; 3737 case tok::objc_package: return ObjCIvarDecl::Package; 3738 } 3739} 3740 3741/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3742/// in order to create an IvarDecl object for it. 3743Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3744 SourceLocation DeclStart, 3745 Declarator &D, ExprTy *BitfieldWidth, 3746 tok::ObjCKeywordKind Visibility) { 3747 3748 IdentifierInfo *II = D.getIdentifier(); 3749 Expr *BitWidth = (Expr*)BitfieldWidth; 3750 SourceLocation Loc = DeclStart; 3751 if (II) Loc = D.getIdentifierLoc(); 3752 3753 // FIXME: Unnamed fields can be handled in various different ways, for 3754 // example, unnamed unions inject all members into the struct namespace! 3755 3756 QualType T = GetTypeForDeclarator(D, S); 3757 bool InvalidDecl = false; 3758 if (T.isNull()) { 3759 InvalidDecl = true; 3760 T = Context.IntTy; 3761 } 3762 3763 if (BitWidth) { 3764 // 6.7.2.1p3, 6.7.2.1p4 3765 if (VerifyBitField(Loc, II, T, BitWidth)) { 3766 InvalidDecl = true; 3767 DeleteExpr(BitWidth); 3768 BitWidth = 0; 3769 } 3770 } else { 3771 // Not a bitfield. 3772 3773 // validate II. 3774 3775 } 3776 3777 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3778 // than a variably modified type. 3779 if (T->isVariablyModifiedType()) { 3780 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3781 InvalidDecl = true; 3782 } 3783 3784 // Get the visibility (access control) for this ivar. 3785 ObjCIvarDecl::AccessControl ac = 3786 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3787 : ObjCIvarDecl::None; 3788 3789 // Construct the decl. 3790 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3791 (Expr *)BitfieldWidth); 3792 3793 if (II) { 3794 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3795 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3796 && !isa<TagDecl>(PrevDecl)) { 3797 Diag(Loc, diag::err_duplicate_member) << II; 3798 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3799 NewID->setInvalidDecl(); 3800 } 3801 } 3802 3803 // Process attributes attached to the ivar. 3804 ProcessDeclAttributes(NewID, D); 3805 3806 if (D.getInvalidType() || InvalidDecl) 3807 NewID->setInvalidDecl(); 3808 3809 if (II) { 3810 // FIXME: When interfaces are DeclContexts, we'll need to add 3811 // these to the interface. 3812 S->AddDecl(DeclPtrTy::make(NewID)); 3813 IdResolver.AddDecl(NewID); 3814 } 3815 3816 return DeclPtrTy::make(NewID); 3817} 3818 3819void Sema::ActOnFields(Scope* S, 3820 SourceLocation RecLoc, DeclPtrTy RecDecl, 3821 DeclPtrTy *Fields, unsigned NumFields, 3822 SourceLocation LBrac, SourceLocation RBrac, 3823 AttributeList *Attr) { 3824 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3825 assert(EnclosingDecl && "missing record or interface decl"); 3826 3827 // If the decl this is being inserted into is invalid, then it may be a 3828 // redeclaration or some other bogus case. Don't try to add fields to it. 3829 if (EnclosingDecl->isInvalidDecl()) { 3830 // FIXME: Deallocate fields? 3831 return; 3832 } 3833 3834 3835 // Verify that all the fields are okay. 3836 unsigned NumNamedMembers = 0; 3837 llvm::SmallVector<FieldDecl*, 32> RecFields; 3838 3839 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3840 for (unsigned i = 0; i != NumFields; ++i) { 3841 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3842 3843 // Get the type for the field. 3844 Type *FDTy = FD->getType().getTypePtr(); 3845 3846 if (!FD->isAnonymousStructOrUnion()) { 3847 // Remember all fields written by the user. 3848 RecFields.push_back(FD); 3849 } 3850 3851 // If the field is already invalid for some reason, don't emit more 3852 // diagnostics about it. 3853 if (FD->isInvalidDecl()) 3854 continue; 3855 3856 // C99 6.7.2.1p2: 3857 // A structure or union shall not contain a member with 3858 // incomplete or function type (hence, a structure shall not 3859 // contain an instance of itself, but may contain a pointer to 3860 // an instance of itself), except that the last member of a 3861 // structure with more than one named member may have incomplete 3862 // array type; such a structure (and any union containing, 3863 // possibly recursively, a member that is such a structure) 3864 // shall not be a member of a structure or an element of an 3865 // array. 3866 if (FDTy->isFunctionType()) { 3867 // Field declared as a function. 3868 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3869 << FD->getDeclName(); 3870 FD->setInvalidDecl(); 3871 EnclosingDecl->setInvalidDecl(); 3872 continue; 3873 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3874 Record && Record->isStruct()) { 3875 // Flexible array member. 3876 if (NumNamedMembers < 1) { 3877 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3878 << FD->getDeclName(); 3879 FD->setInvalidDecl(); 3880 EnclosingDecl->setInvalidDecl(); 3881 continue; 3882 } 3883 // Okay, we have a legal flexible array member at the end of the struct. 3884 if (Record) 3885 Record->setHasFlexibleArrayMember(true); 3886 } else if (!FDTy->isDependentType() && 3887 RequireCompleteType(FD->getLocation(), FD->getType(), 3888 diag::err_field_incomplete)) { 3889 // Incomplete type 3890 FD->setInvalidDecl(); 3891 EnclosingDecl->setInvalidDecl(); 3892 continue; 3893 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3894 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3895 // If this is a member of a union, then entire union becomes "flexible". 3896 if (Record && Record->isUnion()) { 3897 Record->setHasFlexibleArrayMember(true); 3898 } else { 3899 // If this is a struct/class and this is not the last element, reject 3900 // it. Note that GCC supports variable sized arrays in the middle of 3901 // structures. 3902 if (i != NumFields-1) 3903 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3904 << FD->getDeclName(); 3905 else { 3906 // We support flexible arrays at the end of structs in 3907 // other structs as an extension. 3908 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3909 << FD->getDeclName(); 3910 if (Record) 3911 Record->setHasFlexibleArrayMember(true); 3912 } 3913 } 3914 } 3915 } else if (FDTy->isObjCInterfaceType()) { 3916 /// A field cannot be an Objective-c object 3917 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3918 FD->setInvalidDecl(); 3919 EnclosingDecl->setInvalidDecl(); 3920 continue; 3921 } 3922 // Keep track of the number of named members. 3923 if (FD->getIdentifier()) 3924 ++NumNamedMembers; 3925 } 3926 3927 // Okay, we successfully defined 'Record'. 3928 if (Record) { 3929 Record->completeDefinition(Context); 3930 } else { 3931 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3932 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3933 ID->setIVarList(ClsFields, RecFields.size(), Context); 3934 ID->setLocEnd(RBrac); 3935 3936 // Must enforce the rule that ivars in the base classes may not be 3937 // duplicates. 3938 if (ID->getSuperClass()) { 3939 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3940 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3941 ObjCIvarDecl* Ivar = (*IVI); 3942 IdentifierInfo *II = Ivar->getIdentifier(); 3943 ObjCIvarDecl* prevIvar = 3944 ID->getSuperClass()->lookupInstanceVariable(Context, II); 3945 if (prevIvar) { 3946 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3947 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3948 } 3949 } 3950 } 3951 } else if (ObjCImplementationDecl *IMPDecl = 3952 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3953 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3954 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3955 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3956 } 3957 } 3958 3959 if (Attr) 3960 ProcessDeclAttributeList(Record, Attr); 3961} 3962 3963EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 3964 EnumConstantDecl *LastEnumConst, 3965 SourceLocation IdLoc, 3966 IdentifierInfo *Id, 3967 ExprArg val) { 3968 Expr *Val = (Expr *)val.get(); 3969 3970 llvm::APSInt EnumVal(32); 3971 QualType EltTy; 3972 if (Val && !Val->isTypeDependent()) { 3973 // Make sure to promote the operand type to int. 3974 UsualUnaryConversions(Val); 3975 if (Val != val.get()) { 3976 val.release(); 3977 val = Val; 3978 } 3979 3980 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3981 SourceLocation ExpLoc; 3982 if (!Val->isValueDependent() && 3983 VerifyIntegerConstantExpression(Val, &EnumVal)) { 3984 Val = 0; 3985 } else { 3986 EltTy = Val->getType(); 3987 } 3988 } 3989 3990 if (!Val) { 3991 if (LastEnumConst) { 3992 // Assign the last value + 1. 3993 EnumVal = LastEnumConst->getInitVal(); 3994 ++EnumVal; 3995 3996 // Check for overflow on increment. 3997 if (EnumVal < LastEnumConst->getInitVal()) 3998 Diag(IdLoc, diag::warn_enum_value_overflow); 3999 4000 EltTy = LastEnumConst->getType(); 4001 } else { 4002 // First value, set to zero. 4003 EltTy = Context.IntTy; 4004 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4005 } 4006 } 4007 4008 val.release(); 4009 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4010 Val, EnumVal); 4011} 4012 4013 4014Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4015 DeclPtrTy lastEnumConst, 4016 SourceLocation IdLoc, 4017 IdentifierInfo *Id, 4018 SourceLocation EqualLoc, ExprTy *val) { 4019 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4020 EnumConstantDecl *LastEnumConst = 4021 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4022 Expr *Val = static_cast<Expr*>(val); 4023 4024 // The scope passed in may not be a decl scope. Zip up the scope tree until 4025 // we find one that is. 4026 S = getNonFieldDeclScope(S); 4027 4028 // Verify that there isn't already something declared with this name in this 4029 // scope. 4030 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4031 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4032 // Maybe we will complain about the shadowed template parameter. 4033 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4034 // Just pretend that we didn't see the previous declaration. 4035 PrevDecl = 0; 4036 } 4037 4038 if (PrevDecl) { 4039 // When in C++, we may get a TagDecl with the same name; in this case the 4040 // enum constant will 'hide' the tag. 4041 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4042 "Received TagDecl when not in C++!"); 4043 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4044 if (isa<EnumConstantDecl>(PrevDecl)) 4045 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4046 else 4047 Diag(IdLoc, diag::err_redefinition) << Id; 4048 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4049 if (Val) Val->Destroy(Context); 4050 return DeclPtrTy(); 4051 } 4052 } 4053 4054 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4055 IdLoc, Id, Owned(Val)); 4056 4057 // Register this decl in the current scope stack. 4058 if (New) 4059 PushOnScopeChains(New, S); 4060 4061 return DeclPtrTy::make(New); 4062} 4063 4064// FIXME: For consistency with ActOnFields(), we should have the parser 4065// pass in the source location for the left/right braces. 4066void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4067 DeclPtrTy *Elements, unsigned NumElements) { 4068 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4069 QualType EnumType = Context.getTypeDeclType(Enum); 4070 4071 // TODO: If the result value doesn't fit in an int, it must be a long or long 4072 // long value. ISO C does not support this, but GCC does as an extension, 4073 // emit a warning. 4074 unsigned IntWidth = Context.Target.getIntWidth(); 4075 4076 // Verify that all the values are okay, compute the size of the values, and 4077 // reverse the list. 4078 unsigned NumNegativeBits = 0; 4079 unsigned NumPositiveBits = 0; 4080 4081 // Keep track of whether all elements have type int. 4082 bool AllElementsInt = true; 4083 4084 for (unsigned i = 0; i != NumElements; ++i) { 4085 EnumConstantDecl *ECD = 4086 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4087 if (!ECD) continue; // Already issued a diagnostic. 4088 4089 // If the enum value doesn't fit in an int, emit an extension warning. 4090 const llvm::APSInt &InitVal = ECD->getInitVal(); 4091 assert(InitVal.getBitWidth() >= IntWidth && 4092 "Should have promoted value to int"); 4093 if (InitVal.getBitWidth() > IntWidth) { 4094 llvm::APSInt V(InitVal); 4095 V.trunc(IntWidth); 4096 V.extend(InitVal.getBitWidth()); 4097 if (V != InitVal) 4098 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4099 << InitVal.toString(10); 4100 } 4101 4102 // Keep track of the size of positive and negative values. 4103 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4104 NumPositiveBits = std::max(NumPositiveBits, 4105 (unsigned)InitVal.getActiveBits()); 4106 else 4107 NumNegativeBits = std::max(NumNegativeBits, 4108 (unsigned)InitVal.getMinSignedBits()); 4109 4110 // Keep track of whether every enum element has type int (very commmon). 4111 if (AllElementsInt) 4112 AllElementsInt = ECD->getType() == Context.IntTy; 4113 } 4114 4115 // Figure out the type that should be used for this enum. 4116 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4117 QualType BestType; 4118 unsigned BestWidth; 4119 4120 if (NumNegativeBits) { 4121 // If there is a negative value, figure out the smallest integer type (of 4122 // int/long/longlong) that fits. 4123 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4124 BestType = Context.IntTy; 4125 BestWidth = IntWidth; 4126 } else { 4127 BestWidth = Context.Target.getLongWidth(); 4128 4129 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4130 BestType = Context.LongTy; 4131 else { 4132 BestWidth = Context.Target.getLongLongWidth(); 4133 4134 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4135 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4136 BestType = Context.LongLongTy; 4137 } 4138 } 4139 } else { 4140 // If there is no negative value, figure out which of uint, ulong, ulonglong 4141 // fits. 4142 if (NumPositiveBits <= IntWidth) { 4143 BestType = Context.UnsignedIntTy; 4144 BestWidth = IntWidth; 4145 } else if (NumPositiveBits <= 4146 (BestWidth = Context.Target.getLongWidth())) { 4147 BestType = Context.UnsignedLongTy; 4148 } else { 4149 BestWidth = Context.Target.getLongLongWidth(); 4150 assert(NumPositiveBits <= BestWidth && 4151 "How could an initializer get larger than ULL?"); 4152 BestType = Context.UnsignedLongLongTy; 4153 } 4154 } 4155 4156 // Loop over all of the enumerator constants, changing their types to match 4157 // the type of the enum if needed. 4158 for (unsigned i = 0; i != NumElements; ++i) { 4159 EnumConstantDecl *ECD = 4160 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4161 if (!ECD) continue; // Already issued a diagnostic. 4162 4163 // Standard C says the enumerators have int type, but we allow, as an 4164 // extension, the enumerators to be larger than int size. If each 4165 // enumerator value fits in an int, type it as an int, otherwise type it the 4166 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4167 // that X has type 'int', not 'unsigned'. 4168 if (ECD->getType() == Context.IntTy) { 4169 // Make sure the init value is signed. 4170 llvm::APSInt IV = ECD->getInitVal(); 4171 IV.setIsSigned(true); 4172 ECD->setInitVal(IV); 4173 4174 if (getLangOptions().CPlusPlus) 4175 // C++ [dcl.enum]p4: Following the closing brace of an 4176 // enum-specifier, each enumerator has the type of its 4177 // enumeration. 4178 ECD->setType(EnumType); 4179 continue; // Already int type. 4180 } 4181 4182 // Determine whether the value fits into an int. 4183 llvm::APSInt InitVal = ECD->getInitVal(); 4184 bool FitsInInt; 4185 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4186 FitsInInt = InitVal.getActiveBits() < IntWidth; 4187 else 4188 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4189 4190 // If it fits into an integer type, force it. Otherwise force it to match 4191 // the enum decl type. 4192 QualType NewTy; 4193 unsigned NewWidth; 4194 bool NewSign; 4195 if (FitsInInt) { 4196 NewTy = Context.IntTy; 4197 NewWidth = IntWidth; 4198 NewSign = true; 4199 } else if (ECD->getType() == BestType) { 4200 // Already the right type! 4201 if (getLangOptions().CPlusPlus) 4202 // C++ [dcl.enum]p4: Following the closing brace of an 4203 // enum-specifier, each enumerator has the type of its 4204 // enumeration. 4205 ECD->setType(EnumType); 4206 continue; 4207 } else { 4208 NewTy = BestType; 4209 NewWidth = BestWidth; 4210 NewSign = BestType->isSignedIntegerType(); 4211 } 4212 4213 // Adjust the APSInt value. 4214 InitVal.extOrTrunc(NewWidth); 4215 InitVal.setIsSigned(NewSign); 4216 ECD->setInitVal(InitVal); 4217 4218 // Adjust the Expr initializer and type. 4219 if (ECD->getInitExpr()) 4220 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4221 /*isLvalue=*/false)); 4222 if (getLangOptions().CPlusPlus) 4223 // C++ [dcl.enum]p4: Following the closing brace of an 4224 // enum-specifier, each enumerator has the type of its 4225 // enumeration. 4226 ECD->setType(EnumType); 4227 else 4228 ECD->setType(NewTy); 4229 } 4230 4231 Enum->completeDefinition(Context, BestType); 4232} 4233 4234Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4235 ExprArg expr) { 4236 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4237 4238 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4239 Loc, AsmString)); 4240} 4241 4242