SemaDecl.cpp revision 3603e0c11af0d958225d8db2f25ed2683d652436
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 "SemaInherit.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/AST/DeclObjC.h" 20#include "clang/AST/DeclTemplate.h" 21#include "clang/AST/ExprCXX.h" 22#include "clang/AST/StmtCXX.h" 23#include "clang/Parse/DeclSpec.h" 24#include "clang/Basic/TargetInfo.h" 25#include "clang/Basic/SourceManager.h" 26// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 27#include "clang/Lex/Preprocessor.h" 28#include "clang/Lex/HeaderSearch.h" 29#include "llvm/ADT/SmallSet.h" 30#include "llvm/ADT/STLExtras.h" 31#include <algorithm> 32#include <functional> 33using namespace clang; 34 35/// getDeclName - Return a pretty name for the specified decl if possible, or 36/// an empty string if not. This is used for pretty crash reporting. 37std::string Sema::getDeclName(DeclPtrTy d) { 38 Decl *D = d.getAs<Decl>(); 39 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 40 return DN->getQualifiedNameAsString(); 41 return ""; 42} 43 44Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 45 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 46} 47 48/// \brief If the identifier refers to a type name within this scope, 49/// return the declaration of that type. 50/// 51/// This routine performs ordinary name lookup of the identifier II 52/// within the given scope, with optional C++ scope specifier SS, to 53/// determine whether the name refers to a type. If so, returns an 54/// opaque pointer (actually a QualType) corresponding to that 55/// type. Otherwise, returns NULL. 56/// 57/// If name lookup results in an ambiguity, this routine will complain 58/// and then return NULL. 59Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 60 Scope *S, const CXXScopeSpec *SS) { 61 // C++ [temp.res]p3: 62 // A qualified-id that refers to a type and in which the 63 // nested-name-specifier depends on a template-parameter (14.6.2) 64 // shall be prefixed by the keyword typename to indicate that the 65 // qualified-id denotes a type, forming an 66 // elaborated-type-specifier (7.1.5.3). 67 // 68 // We therefore do not perform any name lookup if the result would 69 // refer to a member of an unknown specialization. 70 if (SS && isUnknownSpecialization(*SS)) 71 return 0; 72 73 LookupResult Result 74 = LookupParsedName(S, SS, &II, LookupOrdinaryName, false, false); 75 76 NamedDecl *IIDecl = 0; 77 switch (Result.getKind()) { 78 case LookupResult::NotFound: 79 case LookupResult::FoundOverloaded: 80 return 0; 81 82 case LookupResult::AmbiguousBaseSubobjectTypes: 83 case LookupResult::AmbiguousBaseSubobjects: 84 case LookupResult::AmbiguousReference: { 85 // Look to see if we have a type anywhere in the list of results. 86 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 87 Res != ResEnd; ++Res) { 88 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 89 if (!IIDecl || 90 (*Res)->getLocation().getRawEncoding() < 91 IIDecl->getLocation().getRawEncoding()) 92 IIDecl = *Res; 93 } 94 } 95 96 if (!IIDecl) { 97 // None of the entities we found is a type, so there is no way 98 // to even assume that the result is a type. In this case, don't 99 // complain about the ambiguity. The parser will either try to 100 // perform this lookup again (e.g., as an object name), which 101 // will produce the ambiguity, or will complain that it expected 102 // a type name. 103 Result.Destroy(); 104 return 0; 105 } 106 107 // We found a type within the ambiguous lookup; diagnose the 108 // ambiguity and then return that type. This might be the right 109 // answer, or it might not be, but it suppresses any attempt to 110 // perform the name lookup again. 111 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 112 break; 113 } 114 115 case LookupResult::Found: 116 IIDecl = Result.getAsDecl(); 117 break; 118 } 119 120 if (IIDecl) { 121 QualType T; 122 123 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 124 // Check whether we can use this type 125 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 126 127 if (getLangOptions().CPlusPlus) { 128 // C++ [temp.local]p2: 129 // Within the scope of a class template specialization or 130 // partial specialization, when the injected-class-name is 131 // not followed by a <, it is equivalent to the 132 // injected-class-name followed by the template-argument s 133 // of the class template specialization or partial 134 // specialization enclosed in <>. 135 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 136 if (RD->isInjectedClassName()) 137 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 138 T = Template->getInjectedClassNameType(Context); 139 } 140 141 if (T.isNull()) 142 T = Context.getTypeDeclType(TD); 143 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 144 // Check whether we can use this interface. 145 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 146 147 T = Context.getObjCInterfaceType(IDecl); 148 } else 149 return 0; 150 151 if (SS) 152 T = getQualifiedNameType(*SS, T); 153 154 return T.getAsOpaquePtr(); 155 } 156 157 return 0; 158} 159 160/// isTagName() - This method is called *for error recovery purposes only* 161/// to determine if the specified name is a valid tag name ("struct foo"). If 162/// so, this returns the TST for the tag corresponding to it (TST_enum, 163/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 164/// where the user forgot to specify the tag. 165DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 166 // Do a tag name lookup in this scope. 167 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 168 if (R.getKind() == LookupResult::Found) 169 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 170 switch (TD->getTagKind()) { 171 case TagDecl::TK_struct: return DeclSpec::TST_struct; 172 case TagDecl::TK_union: return DeclSpec::TST_union; 173 case TagDecl::TK_class: return DeclSpec::TST_class; 174 case TagDecl::TK_enum: return DeclSpec::TST_enum; 175 } 176 } 177 178 return DeclSpec::TST_unspecified; 179} 180 181 182 183DeclContext *Sema::getContainingDC(DeclContext *DC) { 184 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 185 // A C++ out-of-line method will return to the file declaration context. 186 if (MD->isOutOfLine()) 187 return MD->getLexicalDeclContext(); 188 189 // A C++ inline method is parsed *after* the topmost class it was declared 190 // in is fully parsed (it's "complete"). 191 // The parsing of a C++ inline method happens at the declaration context of 192 // the topmost (non-nested) class it is lexically declared in. 193 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 194 DC = MD->getParent(); 195 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 196 DC = RD; 197 198 // Return the declaration context of the topmost class the inline method is 199 // declared in. 200 return DC; 201 } 202 203 if (isa<ObjCMethodDecl>(DC)) 204 return Context.getTranslationUnitDecl(); 205 206 return DC->getLexicalParent(); 207} 208 209void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 210 assert(getContainingDC(DC) == CurContext && 211 "The next DeclContext should be lexically contained in the current one."); 212 CurContext = DC; 213 S->setEntity(DC); 214} 215 216void Sema::PopDeclContext() { 217 assert(CurContext && "DeclContext imbalance!"); 218 219 CurContext = getContainingDC(CurContext); 220} 221 222/// EnterDeclaratorContext - Used when we must lookup names in the context 223/// of a declarator's nested name specifier. 224void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 225 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 226 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 227 CurContext = DC; 228 assert(CurContext && "No context?"); 229 S->setEntity(CurContext); 230} 231 232void Sema::ExitDeclaratorContext(Scope *S) { 233 S->setEntity(PreDeclaratorDC); 234 PreDeclaratorDC = 0; 235 236 // Reset CurContext to the nearest enclosing context. 237 while (!S->getEntity() && S->getParent()) 238 S = S->getParent(); 239 CurContext = static_cast<DeclContext*>(S->getEntity()); 240 assert(CurContext && "No context?"); 241} 242 243/// \brief Determine whether we allow overloading of the function 244/// PrevDecl with another declaration. 245/// 246/// This routine determines whether overloading is possible, not 247/// whether some new function is actually an overload. It will return 248/// true in C++ (where we can always provide overloads) or, as an 249/// extension, in C when the previous function is already an 250/// overloaded function declaration or has the "overloadable" 251/// attribute. 252static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 253 if (Context.getLangOptions().CPlusPlus) 254 return true; 255 256 if (isa<OverloadedFunctionDecl>(PrevDecl)) 257 return true; 258 259 return PrevDecl->getAttr<OverloadableAttr>(Context) != 0; 260} 261 262/// Add this decl to the scope shadowed decl chains. 263void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 264 // Move up the scope chain until we find the nearest enclosing 265 // non-transparent context. The declaration will be introduced into this 266 // scope. 267 while (S->getEntity() && 268 ((DeclContext *)S->getEntity())->isTransparentContext()) 269 S = S->getParent(); 270 271 S->AddDecl(DeclPtrTy::make(D)); 272 273 // Add scoped declarations into their context, so that they can be 274 // found later. Declarations without a context won't be inserted 275 // into any context. 276 CurContext->addDecl(Context, D); 277 278 // C++ [basic.scope]p4: 279 // -- exactly one declaration shall declare a class name or 280 // enumeration name that is not a typedef name and the other 281 // declarations shall all refer to the same object or 282 // enumerator, or all refer to functions and function templates; 283 // in this case the class name or enumeration name is hidden. 284 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 285 // We are pushing the name of a tag (enum or class). 286 if (CurContext->getLookupContext() 287 == TD->getDeclContext()->getLookupContext()) { 288 // We're pushing the tag into the current context, which might 289 // require some reshuffling in the identifier resolver. 290 IdentifierResolver::iterator 291 I = IdResolver.begin(TD->getDeclName()), 292 IEnd = IdResolver.end(); 293 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 294 NamedDecl *PrevDecl = *I; 295 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 296 PrevDecl = *I, ++I) { 297 if (TD->declarationReplaces(*I)) { 298 // This is a redeclaration. Remove it from the chain and 299 // break out, so that we'll add in the shadowed 300 // declaration. 301 S->RemoveDecl(DeclPtrTy::make(*I)); 302 if (PrevDecl == *I) { 303 IdResolver.RemoveDecl(*I); 304 IdResolver.AddDecl(TD); 305 return; 306 } else { 307 IdResolver.RemoveDecl(*I); 308 break; 309 } 310 } 311 } 312 313 // There is already a declaration with the same name in the same 314 // scope, which is not a tag declaration. It must be found 315 // before we find the new declaration, so insert the new 316 // declaration at the end of the chain. 317 IdResolver.AddShadowedDecl(TD, PrevDecl); 318 319 return; 320 } 321 } 322 } else if (isa<FunctionDecl>(D) && 323 AllowOverloadingOfFunction(D, Context)) { 324 // We are pushing the name of a function, which might be an 325 // overloaded name. 326 FunctionDecl *FD = cast<FunctionDecl>(D); 327 IdentifierResolver::iterator Redecl 328 = std::find_if(IdResolver.begin(FD->getDeclName()), 329 IdResolver.end(), 330 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 331 FD)); 332 if (Redecl != IdResolver.end() && 333 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 334 // There is already a declaration of a function on our 335 // IdResolver chain. Replace it with this declaration. 336 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 337 IdResolver.RemoveDecl(*Redecl); 338 } 339 } else if (isa<ObjCInterfaceDecl>(D)) { 340 // We're pushing an Objective-C interface into the current 341 // context. If there is already an alias declaration, remove it first. 342 for (IdentifierResolver::iterator 343 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 344 I != IEnd; ++I) { 345 if (isa<ObjCCompatibleAliasDecl>(*I)) { 346 S->RemoveDecl(DeclPtrTy::make(*I)); 347 IdResolver.RemoveDecl(*I); 348 break; 349 } 350 } 351 } 352 353 IdResolver.AddDecl(D); 354} 355 356void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 357 if (S->decl_empty()) return; 358 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 359 "Scope shouldn't contain decls!"); 360 361 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 362 I != E; ++I) { 363 Decl *TmpD = (*I).getAs<Decl>(); 364 assert(TmpD && "This decl didn't get pushed??"); 365 366 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 367 NamedDecl *D = cast<NamedDecl>(TmpD); 368 369 if (!D->getDeclName()) continue; 370 371 // Remove this name from our lexical scope. 372 IdResolver.RemoveDecl(D); 373 } 374} 375 376/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 377/// return 0 if one not found. 378ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 379 // The third "scope" argument is 0 since we aren't enabling lazy built-in 380 // creation from this context. 381 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 382 383 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 384} 385 386/// getNonFieldDeclScope - Retrieves the innermost scope, starting 387/// from S, where a non-field would be declared. This routine copes 388/// with the difference between C and C++ scoping rules in structs and 389/// unions. For example, the following code is well-formed in C but 390/// ill-formed in C++: 391/// @code 392/// struct S6 { 393/// enum { BAR } e; 394/// }; 395/// 396/// void test_S6() { 397/// struct S6 a; 398/// a.e = BAR; 399/// } 400/// @endcode 401/// For the declaration of BAR, this routine will return a different 402/// scope. The scope S will be the scope of the unnamed enumeration 403/// within S6. In C++, this routine will return the scope associated 404/// with S6, because the enumeration's scope is a transparent 405/// context but structures can contain non-field names. In C, this 406/// routine will return the translation unit scope, since the 407/// enumeration's scope is a transparent context and structures cannot 408/// contain non-field names. 409Scope *Sema::getNonFieldDeclScope(Scope *S) { 410 while (((S->getFlags() & Scope::DeclScope) == 0) || 411 (S->getEntity() && 412 ((DeclContext *)S->getEntity())->isTransparentContext()) || 413 (S->isClassScope() && !getLangOptions().CPlusPlus)) 414 S = S->getParent(); 415 return S; 416} 417 418void Sema::InitBuiltinVaListType() { 419 if (!Context.getBuiltinVaListType().isNull()) 420 return; 421 422 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 423 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 424 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 425 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 426} 427 428/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 429/// file scope. lazily create a decl for it. ForRedeclaration is true 430/// if we're creating this built-in in anticipation of redeclaring the 431/// built-in. 432NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 433 Scope *S, bool ForRedeclaration, 434 SourceLocation Loc) { 435 Builtin::ID BID = (Builtin::ID)bid; 436 437 if (Context.BuiltinInfo.hasVAListUse(BID)) 438 InitBuiltinVaListType(); 439 440 ASTContext::GetBuiltinTypeError Error; 441 QualType R = Context.GetBuiltinType(BID, Error); 442 switch (Error) { 443 case ASTContext::GE_None: 444 // Okay 445 break; 446 447 case ASTContext::GE_Missing_FILE: 448 if (ForRedeclaration) 449 Diag(Loc, diag::err_implicit_decl_requires_stdio) 450 << Context.BuiltinInfo.GetName(BID); 451 return 0; 452 } 453 454 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 455 Diag(Loc, diag::ext_implicit_lib_function_decl) 456 << Context.BuiltinInfo.GetName(BID) 457 << R; 458 if (Context.BuiltinInfo.getHeaderName(BID) && 459 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 460 != Diagnostic::Ignored) 461 Diag(Loc, diag::note_please_include_header) 462 << Context.BuiltinInfo.getHeaderName(BID) 463 << Context.BuiltinInfo.GetName(BID); 464 } 465 466 FunctionDecl *New = FunctionDecl::Create(Context, 467 Context.getTranslationUnitDecl(), 468 Loc, II, R, 469 FunctionDecl::Extern, false, 470 /*hasPrototype=*/true); 471 New->setImplicit(); 472 473 // Create Decl objects for each parameter, adding them to the 474 // FunctionDecl. 475 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 476 llvm::SmallVector<ParmVarDecl*, 16> Params; 477 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 478 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 479 FT->getArgType(i), VarDecl::None, 0)); 480 New->setParams(Context, Params.data(), Params.size()); 481 } 482 483 AddKnownFunctionAttributes(New); 484 485 // TUScope is the translation-unit scope to insert this function into. 486 // FIXME: This is hideous. We need to teach PushOnScopeChains to 487 // relate Scopes to DeclContexts, and probably eliminate CurContext 488 // entirely, but we're not there yet. 489 DeclContext *SavedContext = CurContext; 490 CurContext = Context.getTranslationUnitDecl(); 491 PushOnScopeChains(New, TUScope); 492 CurContext = SavedContext; 493 return New; 494} 495 496/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 497/// everything from the standard library is defined. 498NamespaceDecl *Sema::GetStdNamespace() { 499 if (!StdNamespace) { 500 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 501 DeclContext *Global = Context.getTranslationUnitDecl(); 502 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 503 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 504 } 505 return StdNamespace; 506} 507 508/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 509/// same name and scope as a previous declaration 'Old'. Figure out 510/// how to resolve this situation, merging decls or emitting 511/// diagnostics as appropriate. If there was an error, set New to be invalid. 512/// 513void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 514 // If either decl is known invalid already, set the new one to be invalid and 515 // don't bother doing any merging checks. 516 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 517 return New->setInvalidDecl(); 518 519 bool objc_types = false; 520 521 // Allow multiple definitions for ObjC built-in typedefs. 522 // FIXME: Verify the underlying types are equivalent! 523 if (getLangOptions().ObjC1) { 524 const IdentifierInfo *TypeID = New->getIdentifier(); 525 switch (TypeID->getLength()) { 526 default: break; 527 case 2: 528 if (!TypeID->isStr("id")) 529 break; 530 Context.setObjCIdType(Context.getTypeDeclType(New)); 531 objc_types = true; 532 break; 533 case 5: 534 if (!TypeID->isStr("Class")) 535 break; 536 Context.setObjCClassType(Context.getTypeDeclType(New)); 537 return; 538 case 3: 539 if (!TypeID->isStr("SEL")) 540 break; 541 Context.setObjCSelType(Context.getTypeDeclType(New)); 542 return; 543 case 8: 544 if (!TypeID->isStr("Protocol")) 545 break; 546 Context.setObjCProtoType(New->getUnderlyingType()); 547 return; 548 } 549 // Fall through - the typedef name was not a builtin type. 550 } 551 // Verify the old decl was also a type. 552 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 553 if (!Old) { 554 Diag(New->getLocation(), diag::err_redefinition_different_kind) 555 << New->getDeclName(); 556 if (OldD->getLocation().isValid()) 557 Diag(OldD->getLocation(), diag::note_previous_definition); 558 return New->setInvalidDecl(); 559 } 560 561 // Determine the "old" type we'll use for checking and diagnostics. 562 QualType OldType; 563 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 564 OldType = OldTypedef->getUnderlyingType(); 565 else 566 OldType = Context.getTypeDeclType(Old); 567 568 // If the typedef types are not identical, reject them in all languages and 569 // with any extensions enabled. 570 571 if (OldType != New->getUnderlyingType() && 572 Context.getCanonicalType(OldType) != 573 Context.getCanonicalType(New->getUnderlyingType())) { 574 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 575 << New->getUnderlyingType() << OldType; 576 if (Old->getLocation().isValid()) 577 Diag(Old->getLocation(), diag::note_previous_definition); 578 return New->setInvalidDecl(); 579 } 580 581 if (objc_types || getLangOptions().Microsoft) 582 return; 583 584 // C++ [dcl.typedef]p2: 585 // In a given non-class scope, a typedef specifier can be used to 586 // redefine the name of any type declared in that scope to refer 587 // to the type to which it already refers. 588 if (getLangOptions().CPlusPlus) { 589 if (!isa<CXXRecordDecl>(CurContext)) 590 return; 591 Diag(New->getLocation(), diag::err_redefinition) 592 << New->getDeclName(); 593 Diag(Old->getLocation(), diag::note_previous_definition); 594 return New->setInvalidDecl(); 595 } 596 597 // If we have a redefinition of a typedef in C, emit a warning. This warning 598 // is normally mapped to an error, but can be controlled with 599 // -Wtypedef-redefinition. If either the original or the redefinition is 600 // in a system header, don't emit this for compatibility with GCC. 601 if (PP.getDiagnostics().getSuppressSystemWarnings() && 602 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 603 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 604 return; 605 606 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 607 << New->getDeclName(); 608 Diag(Old->getLocation(), diag::note_previous_definition); 609 return; 610} 611 612/// DeclhasAttr - returns true if decl Declaration already has the target 613/// attribute. 614static bool 615DeclHasAttr(ASTContext &Context, const Decl *decl, const Attr *target) { 616 for (const Attr *attr = decl->getAttrs(Context); attr; attr = attr->getNext()) 617 if (attr->getKind() == target->getKind()) 618 return true; 619 620 return false; 621} 622 623/// MergeAttributes - append attributes from the Old decl to the New one. 624static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 625 for (const Attr *attr = Old->getAttrs(C); attr; attr = attr->getNext()) { 626 if (!DeclHasAttr(C, New, attr) && attr->isMerged()) { 627 Attr *NewAttr = attr->clone(C); 628 NewAttr->setInherited(true); 629 New->addAttr(C, NewAttr); 630 } 631 } 632} 633 634/// Used in MergeFunctionDecl to keep track of function parameters in 635/// C. 636struct GNUCompatibleParamWarning { 637 ParmVarDecl *OldParm; 638 ParmVarDecl *NewParm; 639 QualType PromotedType; 640}; 641 642/// MergeFunctionDecl - We just parsed a function 'New' from 643/// declarator D which has the same name and scope as a previous 644/// declaration 'Old'. Figure out how to resolve this situation, 645/// merging decls or emitting diagnostics as appropriate. 646/// 647/// In C++, New and Old must be declarations that are not 648/// overloaded. Use IsOverload to determine whether New and Old are 649/// overloaded, and to select the Old declaration that New should be 650/// merged with. 651/// 652/// Returns true if there was an error, false otherwise. 653bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 654 assert(!isa<OverloadedFunctionDecl>(OldD) && 655 "Cannot merge with an overloaded function declaration"); 656 657 // Verify the old decl was also a function. 658 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 659 if (!Old) { 660 Diag(New->getLocation(), diag::err_redefinition_different_kind) 661 << New->getDeclName(); 662 Diag(OldD->getLocation(), diag::note_previous_definition); 663 return true; 664 } 665 666 // Determine whether the previous declaration was a definition, 667 // implicit declaration, or a declaration. 668 diag::kind PrevDiag; 669 if (Old->isThisDeclarationADefinition()) 670 PrevDiag = diag::note_previous_definition; 671 else if (Old->isImplicit()) 672 PrevDiag = diag::note_previous_implicit_declaration; 673 else 674 PrevDiag = diag::note_previous_declaration; 675 676 QualType OldQType = Context.getCanonicalType(Old->getType()); 677 QualType NewQType = Context.getCanonicalType(New->getType()); 678 679 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 680 New->getStorageClass() == FunctionDecl::Static && 681 Old->getStorageClass() != FunctionDecl::Static) { 682 Diag(New->getLocation(), diag::err_static_non_static) 683 << New; 684 Diag(Old->getLocation(), PrevDiag); 685 return true; 686 } 687 688 if (getLangOptions().CPlusPlus) { 689 // (C++98 13.1p2): 690 // Certain function declarations cannot be overloaded: 691 // -- Function declarations that differ only in the return type 692 // cannot be overloaded. 693 QualType OldReturnType 694 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 695 QualType NewReturnType 696 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 697 if (OldReturnType != NewReturnType) { 698 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 699 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 700 return true; 701 } 702 703 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 704 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 705 if (OldMethod && NewMethod && 706 OldMethod->getLexicalDeclContext() == 707 NewMethod->getLexicalDeclContext()) { 708 // -- Member function declarations with the same name and the 709 // same parameter types cannot be overloaded if any of them 710 // is a static member function declaration. 711 if (OldMethod->isStatic() || NewMethod->isStatic()) { 712 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 713 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 714 return true; 715 } 716 717 // C++ [class.mem]p1: 718 // [...] A member shall not be declared twice in the 719 // member-specification, except that a nested class or member 720 // class template can be declared and then later defined. 721 unsigned NewDiag; 722 if (isa<CXXConstructorDecl>(OldMethod)) 723 NewDiag = diag::err_constructor_redeclared; 724 else if (isa<CXXDestructorDecl>(NewMethod)) 725 NewDiag = diag::err_destructor_redeclared; 726 else if (isa<CXXConversionDecl>(NewMethod)) 727 NewDiag = diag::err_conv_function_redeclared; 728 else 729 NewDiag = diag::err_member_redeclared; 730 731 Diag(New->getLocation(), NewDiag); 732 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 733 } 734 735 // (C++98 8.3.5p3): 736 // All declarations for a function shall agree exactly in both the 737 // return type and the parameter-type-list. 738 if (OldQType == NewQType) 739 return MergeCompatibleFunctionDecls(New, Old); 740 741 // Fall through for conflicting redeclarations and redefinitions. 742 } 743 744 // C: Function types need to be compatible, not identical. This handles 745 // duplicate function decls like "void f(int); void f(enum X);" properly. 746 if (!getLangOptions().CPlusPlus && 747 Context.typesAreCompatible(OldQType, NewQType)) { 748 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 749 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 750 const FunctionProtoType *OldProto = 0; 751 if (isa<FunctionNoProtoType>(NewFuncType) && 752 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 753 // The old declaration provided a function prototype, but the 754 // new declaration does not. Merge in the prototype. 755 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 756 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 757 OldProto->arg_type_end()); 758 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 759 ParamTypes.data(), ParamTypes.size(), 760 OldProto->isVariadic(), 761 OldProto->getTypeQuals()); 762 New->setType(NewQType); 763 New->setHasInheritedPrototype(); 764 765 // Synthesize a parameter for each argument type. 766 llvm::SmallVector<ParmVarDecl*, 16> Params; 767 for (FunctionProtoType::arg_type_iterator 768 ParamType = OldProto->arg_type_begin(), 769 ParamEnd = OldProto->arg_type_end(); 770 ParamType != ParamEnd; ++ParamType) { 771 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 772 SourceLocation(), 0, 773 *ParamType, VarDecl::None, 774 0); 775 Param->setImplicit(); 776 Params.push_back(Param); 777 } 778 779 New->setParams(Context, Params.data(), Params.size()); 780 } 781 782 return MergeCompatibleFunctionDecls(New, Old); 783 } 784 785 // GNU C permits a K&R definition to follow a prototype declaration 786 // if the declared types of the parameters in the K&R definition 787 // match the types in the prototype declaration, even when the 788 // promoted types of the parameters from the K&R definition differ 789 // from the types in the prototype. GCC then keeps the types from 790 // the prototype. 791 // 792 // If a variadic prototype is followed by a non-variadic K&R definition, 793 // the K&R definition becomes variadic. This is sort of an edge case, but 794 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 795 // C99 6.9.1p8. 796 if (!getLangOptions().CPlusPlus && 797 Old->hasPrototype() && !New->hasPrototype() && 798 New->getType()->getAsFunctionProtoType() && 799 Old->getNumParams() == New->getNumParams()) { 800 llvm::SmallVector<QualType, 16> ArgTypes; 801 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 802 const FunctionProtoType *OldProto 803 = Old->getType()->getAsFunctionProtoType(); 804 const FunctionProtoType *NewProto 805 = New->getType()->getAsFunctionProtoType(); 806 807 // Determine whether this is the GNU C extension. 808 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 809 NewProto->getResultType()); 810 bool LooseCompatible = !MergedReturn.isNull(); 811 for (unsigned Idx = 0, End = Old->getNumParams(); 812 LooseCompatible && Idx != End; ++Idx) { 813 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 814 ParmVarDecl *NewParm = New->getParamDecl(Idx); 815 if (Context.typesAreCompatible(OldParm->getType(), 816 NewProto->getArgType(Idx))) { 817 ArgTypes.push_back(NewParm->getType()); 818 } else if (Context.typesAreCompatible(OldParm->getType(), 819 NewParm->getType())) { 820 GNUCompatibleParamWarning Warn 821 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 822 Warnings.push_back(Warn); 823 ArgTypes.push_back(NewParm->getType()); 824 } else 825 LooseCompatible = false; 826 } 827 828 if (LooseCompatible) { 829 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 830 Diag(Warnings[Warn].NewParm->getLocation(), 831 diag::ext_param_promoted_not_compatible_with_prototype) 832 << Warnings[Warn].PromotedType 833 << Warnings[Warn].OldParm->getType(); 834 Diag(Warnings[Warn].OldParm->getLocation(), 835 diag::note_previous_declaration); 836 } 837 838 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 839 ArgTypes.size(), 840 OldProto->isVariadic(), 0)); 841 return MergeCompatibleFunctionDecls(New, Old); 842 } 843 844 // Fall through to diagnose conflicting types. 845 } 846 847 // A function that has already been declared has been redeclared or defined 848 // with a different type- show appropriate diagnostic 849 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 850 // The user has declared a builtin function with an incompatible 851 // signature. 852 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 853 // The function the user is redeclaring is a library-defined 854 // function like 'malloc' or 'printf'. Warn about the 855 // redeclaration, then pretend that we don't know about this 856 // library built-in. 857 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 858 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 859 << Old << Old->getType(); 860 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 861 Old->setInvalidDecl(); 862 return false; 863 } 864 865 PrevDiag = diag::note_previous_builtin_declaration; 866 } 867 868 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 869 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 870 return true; 871} 872 873/// \brief Completes the merge of two function declarations that are 874/// known to be compatible. 875/// 876/// This routine handles the merging of attributes and other 877/// properties of function declarations form the old declaration to 878/// the new declaration, once we know that New is in fact a 879/// redeclaration of Old. 880/// 881/// \returns false 882bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 883 // Merge the attributes 884 MergeAttributes(New, Old, Context); 885 886 // Merge the storage class. 887 if (Old->getStorageClass() != FunctionDecl::Extern) 888 New->setStorageClass(Old->getStorageClass()); 889 890 // Merge "inline" 891 if (Old->isInline()) 892 New->setInline(true); 893 894 // If this function declaration by itself qualifies as a C99 inline 895 // definition (C99 6.7.4p6), but the previous definition did not, 896 // then the function is not a C99 inline definition. 897 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 898 New->setC99InlineDefinition(false); 899 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 900 // Mark all preceding definitions as not being C99 inline definitions. 901 for (const FunctionDecl *Prev = Old; Prev; 902 Prev = Prev->getPreviousDeclaration()) 903 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 904 } 905 906 // Merge "pure" flag. 907 if (Old->isPure()) 908 New->setPure(); 909 910 // Merge the "deleted" flag. 911 if (Old->isDeleted()) 912 New->setDeleted(); 913 914 if (getLangOptions().CPlusPlus) 915 return MergeCXXFunctionDecl(New, Old); 916 917 return false; 918} 919 920/// MergeVarDecl - We just parsed a variable 'New' which has the same name 921/// and scope as a previous declaration 'Old'. Figure out how to resolve this 922/// situation, merging decls or emitting diagnostics as appropriate. 923/// 924/// Tentative definition rules (C99 6.9.2p2) are checked by 925/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 926/// definitions here, since the initializer hasn't been attached. 927/// 928void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 929 // If either decl is invalid, make sure the new one is marked invalid and 930 // don't do any other checking. 931 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 932 return New->setInvalidDecl(); 933 934 // Verify the old decl was also a variable. 935 VarDecl *Old = dyn_cast<VarDecl>(OldD); 936 if (!Old) { 937 Diag(New->getLocation(), diag::err_redefinition_different_kind) 938 << New->getDeclName(); 939 Diag(OldD->getLocation(), diag::note_previous_definition); 940 return New->setInvalidDecl(); 941 } 942 943 MergeAttributes(New, Old, Context); 944 945 // Merge the types 946 QualType MergedT; 947 if (getLangOptions().CPlusPlus) { 948 if (Context.hasSameType(New->getType(), Old->getType())) 949 MergedT = New->getType(); 950 } else { 951 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 952 } 953 if (MergedT.isNull()) { 954 Diag(New->getLocation(), diag::err_redefinition_different_type) 955 << New->getDeclName(); 956 Diag(Old->getLocation(), diag::note_previous_definition); 957 return New->setInvalidDecl(); 958 } 959 New->setType(MergedT); 960 961 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 962 if (New->getStorageClass() == VarDecl::Static && 963 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 964 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 965 Diag(Old->getLocation(), diag::note_previous_definition); 966 return New->setInvalidDecl(); 967 } 968 // C99 6.2.2p4: 969 // For an identifier declared with the storage-class specifier 970 // extern in a scope in which a prior declaration of that 971 // identifier is visible,23) if the prior declaration specifies 972 // internal or external linkage, the linkage of the identifier at 973 // the later declaration is the same as the linkage specified at 974 // the prior declaration. If no prior declaration is visible, or 975 // if the prior declaration specifies no linkage, then the 976 // identifier has external linkage. 977 if (New->hasExternalStorage() && Old->hasLinkage()) 978 /* Okay */; 979 else if (New->getStorageClass() != VarDecl::Static && 980 Old->getStorageClass() == VarDecl::Static) { 981 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 982 Diag(Old->getLocation(), diag::note_previous_definition); 983 return New->setInvalidDecl(); 984 } 985 986 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 987 988 // FIXME: The test for external storage here seems wrong? We still 989 // need to check for mismatches. 990 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 991 // Don't complain about out-of-line definitions of static members. 992 !(Old->getLexicalDeclContext()->isRecord() && 993 !New->getLexicalDeclContext()->isRecord())) { 994 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 995 Diag(Old->getLocation(), diag::note_previous_definition); 996 return New->setInvalidDecl(); 997 } 998 999 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1000 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1001 Diag(Old->getLocation(), diag::note_previous_definition); 1002 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1003 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1004 Diag(Old->getLocation(), diag::note_previous_definition); 1005 } 1006 1007 // Keep a chain of previous declarations. 1008 New->setPreviousDeclaration(Old); 1009} 1010 1011/// CheckParmsForFunctionDef - Check that the parameters of the given 1012/// function are appropriate for the definition of a function. This 1013/// takes care of any checks that cannot be performed on the 1014/// declaration itself, e.g., that the types of each of the function 1015/// parameters are complete. 1016bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1017 bool HasInvalidParm = false; 1018 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1019 ParmVarDecl *Param = FD->getParamDecl(p); 1020 1021 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1022 // function declarator that is part of a function definition of 1023 // that function shall not have incomplete type. 1024 // 1025 // This is also C++ [dcl.fct]p6. 1026 if (!Param->isInvalidDecl() && 1027 RequireCompleteType(Param->getLocation(), Param->getType(), 1028 diag::err_typecheck_decl_incomplete_type)) { 1029 Param->setInvalidDecl(); 1030 HasInvalidParm = true; 1031 } 1032 1033 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1034 // declaration of each parameter shall include an identifier. 1035 if (Param->getIdentifier() == 0 && 1036 !Param->isImplicit() && 1037 !getLangOptions().CPlusPlus) 1038 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1039 } 1040 1041 return HasInvalidParm; 1042} 1043 1044/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1045/// no declarator (e.g. "struct foo;") is parsed. 1046Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1047 // FIXME: Error on auto/register at file scope 1048 // FIXME: Error on inline/virtual/explicit 1049 // FIXME: Error on invalid restrict 1050 // FIXME: Warn on useless __thread 1051 // FIXME: Warn on useless const/volatile 1052 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1053 // FIXME: Warn on useless attributes 1054 TagDecl *Tag = 0; 1055 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1056 DS.getTypeSpecType() == DeclSpec::TST_struct || 1057 DS.getTypeSpecType() == DeclSpec::TST_union || 1058 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1059 if (!DS.getTypeRep()) // We probably had an error 1060 return DeclPtrTy(); 1061 1062 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1063 } 1064 1065 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1066 if (!Record->getDeclName() && Record->isDefinition() && 1067 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1068 if (getLangOptions().CPlusPlus || 1069 Record->getDeclContext()->isRecord()) 1070 return BuildAnonymousStructOrUnion(S, DS, Record); 1071 1072 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1073 << DS.getSourceRange(); 1074 } 1075 1076 // Microsoft allows unnamed struct/union fields. Don't complain 1077 // about them. 1078 // FIXME: Should we support Microsoft's extensions in this area? 1079 if (Record->getDeclName() && getLangOptions().Microsoft) 1080 return DeclPtrTy::make(Tag); 1081 } 1082 1083 if (!DS.isMissingDeclaratorOk() && 1084 DS.getTypeSpecType() != DeclSpec::TST_error) { 1085 // Warn about typedefs of enums without names, since this is an 1086 // extension in both Microsoft an GNU. 1087 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1088 Tag && isa<EnumDecl>(Tag)) { 1089 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1090 << DS.getSourceRange(); 1091 return DeclPtrTy::make(Tag); 1092 } 1093 1094 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1095 << DS.getSourceRange(); 1096 return DeclPtrTy(); 1097 } 1098 1099 return DeclPtrTy::make(Tag); 1100} 1101 1102/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1103/// anonymous struct or union AnonRecord into the owning context Owner 1104/// and scope S. This routine will be invoked just after we realize 1105/// that an unnamed union or struct is actually an anonymous union or 1106/// struct, e.g., 1107/// 1108/// @code 1109/// union { 1110/// int i; 1111/// float f; 1112/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1113/// // f into the surrounding scope.x 1114/// @endcode 1115/// 1116/// This routine is recursive, injecting the names of nested anonymous 1117/// structs/unions into the owning context and scope as well. 1118bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1119 RecordDecl *AnonRecord) { 1120 bool Invalid = false; 1121 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1122 FEnd = AnonRecord->field_end(Context); 1123 F != FEnd; ++F) { 1124 if ((*F)->getDeclName()) { 1125 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1126 LookupOrdinaryName, true); 1127 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1128 // C++ [class.union]p2: 1129 // The names of the members of an anonymous union shall be 1130 // distinct from the names of any other entity in the 1131 // scope in which the anonymous union is declared. 1132 unsigned diagKind 1133 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1134 : diag::err_anonymous_struct_member_redecl; 1135 Diag((*F)->getLocation(), diagKind) 1136 << (*F)->getDeclName(); 1137 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1138 Invalid = true; 1139 } else { 1140 // C++ [class.union]p2: 1141 // For the purpose of name lookup, after the anonymous union 1142 // definition, the members of the anonymous union are 1143 // considered to have been defined in the scope in which the 1144 // anonymous union is declared. 1145 Owner->makeDeclVisibleInContext(Context, *F); 1146 S->AddDecl(DeclPtrTy::make(*F)); 1147 IdResolver.AddDecl(*F); 1148 } 1149 } else if (const RecordType *InnerRecordType 1150 = (*F)->getType()->getAsRecordType()) { 1151 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1152 if (InnerRecord->isAnonymousStructOrUnion()) 1153 Invalid = Invalid || 1154 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1155 } 1156 } 1157 1158 return Invalid; 1159} 1160 1161/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1162/// anonymous structure or union. Anonymous unions are a C++ feature 1163/// (C++ [class.union]) and a GNU C extension; anonymous structures 1164/// are a GNU C and GNU C++ extension. 1165Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1166 RecordDecl *Record) { 1167 DeclContext *Owner = Record->getDeclContext(); 1168 1169 // Diagnose whether this anonymous struct/union is an extension. 1170 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1171 Diag(Record->getLocation(), diag::ext_anonymous_union); 1172 else if (!Record->isUnion()) 1173 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1174 1175 // C and C++ require different kinds of checks for anonymous 1176 // structs/unions. 1177 bool Invalid = false; 1178 if (getLangOptions().CPlusPlus) { 1179 const char* PrevSpec = 0; 1180 // C++ [class.union]p3: 1181 // Anonymous unions declared in a named namespace or in the 1182 // global namespace shall be declared static. 1183 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1184 (isa<TranslationUnitDecl>(Owner) || 1185 (isa<NamespaceDecl>(Owner) && 1186 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1187 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1188 Invalid = true; 1189 1190 // Recover by adding 'static'. 1191 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1192 } 1193 // C++ [class.union]p3: 1194 // A storage class is not allowed in a declaration of an 1195 // anonymous union in a class scope. 1196 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1197 isa<RecordDecl>(Owner)) { 1198 Diag(DS.getStorageClassSpecLoc(), 1199 diag::err_anonymous_union_with_storage_spec); 1200 Invalid = true; 1201 1202 // Recover by removing the storage specifier. 1203 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1204 PrevSpec); 1205 } 1206 1207 // C++ [class.union]p2: 1208 // The member-specification of an anonymous union shall only 1209 // define non-static data members. [Note: nested types and 1210 // functions cannot be declared within an anonymous union. ] 1211 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1212 MemEnd = Record->decls_end(Context); 1213 Mem != MemEnd; ++Mem) { 1214 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1215 // C++ [class.union]p3: 1216 // An anonymous union shall not have private or protected 1217 // members (clause 11). 1218 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1219 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1220 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1221 Invalid = true; 1222 } 1223 } else if ((*Mem)->isImplicit()) { 1224 // Any implicit members are fine. 1225 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1226 // This is a type that showed up in an 1227 // elaborated-type-specifier inside the anonymous struct or 1228 // union, but which actually declares a type outside of the 1229 // anonymous struct or union. It's okay. 1230 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1231 if (!MemRecord->isAnonymousStructOrUnion() && 1232 MemRecord->getDeclName()) { 1233 // This is a nested type declaration. 1234 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1235 << (int)Record->isUnion(); 1236 Invalid = true; 1237 } 1238 } else { 1239 // We have something that isn't a non-static data 1240 // member. Complain about it. 1241 unsigned DK = diag::err_anonymous_record_bad_member; 1242 if (isa<TypeDecl>(*Mem)) 1243 DK = diag::err_anonymous_record_with_type; 1244 else if (isa<FunctionDecl>(*Mem)) 1245 DK = diag::err_anonymous_record_with_function; 1246 else if (isa<VarDecl>(*Mem)) 1247 DK = diag::err_anonymous_record_with_static; 1248 Diag((*Mem)->getLocation(), DK) 1249 << (int)Record->isUnion(); 1250 Invalid = true; 1251 } 1252 } 1253 } 1254 1255 if (!Record->isUnion() && !Owner->isRecord()) { 1256 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1257 << (int)getLangOptions().CPlusPlus; 1258 Invalid = true; 1259 } 1260 1261 // Create a declaration for this anonymous struct/union. 1262 NamedDecl *Anon = 0; 1263 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1264 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1265 /*IdentifierInfo=*/0, 1266 Context.getTypeDeclType(Record), 1267 /*BitWidth=*/0, /*Mutable=*/false); 1268 Anon->setAccess(AS_public); 1269 if (getLangOptions().CPlusPlus) 1270 FieldCollector->Add(cast<FieldDecl>(Anon)); 1271 } else { 1272 VarDecl::StorageClass SC; 1273 switch (DS.getStorageClassSpec()) { 1274 default: assert(0 && "Unknown storage class!"); 1275 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1276 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1277 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1278 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1279 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1280 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1281 case DeclSpec::SCS_mutable: 1282 // mutable can only appear on non-static class members, so it's always 1283 // an error here 1284 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1285 Invalid = true; 1286 SC = VarDecl::None; 1287 break; 1288 } 1289 1290 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1291 /*IdentifierInfo=*/0, 1292 Context.getTypeDeclType(Record), 1293 SC, DS.getSourceRange().getBegin()); 1294 } 1295 Anon->setImplicit(); 1296 1297 // Add the anonymous struct/union object to the current 1298 // context. We'll be referencing this object when we refer to one of 1299 // its members. 1300 Owner->addDecl(Context, Anon); 1301 1302 // Inject the members of the anonymous struct/union into the owning 1303 // context and into the identifier resolver chain for name lookup 1304 // purposes. 1305 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1306 Invalid = true; 1307 1308 // Mark this as an anonymous struct/union type. Note that we do not 1309 // do this until after we have already checked and injected the 1310 // members of this anonymous struct/union type, because otherwise 1311 // the members could be injected twice: once by DeclContext when it 1312 // builds its lookup table, and once by 1313 // InjectAnonymousStructOrUnionMembers. 1314 Record->setAnonymousStructOrUnion(true); 1315 1316 if (Invalid) 1317 Anon->setInvalidDecl(); 1318 1319 return DeclPtrTy::make(Anon); 1320} 1321 1322 1323/// GetNameForDeclarator - Determine the full declaration name for the 1324/// given Declarator. 1325DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1326 switch (D.getKind()) { 1327 case Declarator::DK_Abstract: 1328 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1329 return DeclarationName(); 1330 1331 case Declarator::DK_Normal: 1332 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1333 return DeclarationName(D.getIdentifier()); 1334 1335 case Declarator::DK_Constructor: { 1336 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1337 Ty = Context.getCanonicalType(Ty); 1338 return Context.DeclarationNames.getCXXConstructorName(Ty); 1339 } 1340 1341 case Declarator::DK_Destructor: { 1342 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1343 Ty = Context.getCanonicalType(Ty); 1344 return Context.DeclarationNames.getCXXDestructorName(Ty); 1345 } 1346 1347 case Declarator::DK_Conversion: { 1348 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1349 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1350 Ty = Context.getCanonicalType(Ty); 1351 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1352 } 1353 1354 case Declarator::DK_Operator: 1355 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1356 return Context.DeclarationNames.getCXXOperatorName( 1357 D.getOverloadedOperator()); 1358 } 1359 1360 assert(false && "Unknown name kind"); 1361 return DeclarationName(); 1362} 1363 1364/// isNearlyMatchingFunction - Determine whether the C++ functions 1365/// Declaration and Definition are "nearly" matching. This heuristic 1366/// is used to improve diagnostics in the case where an out-of-line 1367/// function definition doesn't match any declaration within 1368/// the class or namespace. 1369static bool isNearlyMatchingFunction(ASTContext &Context, 1370 FunctionDecl *Declaration, 1371 FunctionDecl *Definition) { 1372 if (Declaration->param_size() != Definition->param_size()) 1373 return false; 1374 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1375 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1376 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1377 1378 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1379 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1380 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1381 return false; 1382 } 1383 1384 return true; 1385} 1386 1387Sema::DeclPtrTy 1388Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1389 DeclarationName Name = GetNameForDeclarator(D); 1390 1391 // All of these full declarators require an identifier. If it doesn't have 1392 // one, the ParsedFreeStandingDeclSpec action should be used. 1393 if (!Name) { 1394 if (!D.isInvalidType()) // Reject this if we think it is valid. 1395 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1396 diag::err_declarator_need_ident) 1397 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1398 return DeclPtrTy(); 1399 } 1400 1401 // The scope passed in may not be a decl scope. Zip up the scope tree until 1402 // we find one that is. 1403 while ((S->getFlags() & Scope::DeclScope) == 0 || 1404 (S->getFlags() & Scope::TemplateParamScope) != 0) 1405 S = S->getParent(); 1406 1407 DeclContext *DC; 1408 NamedDecl *PrevDecl; 1409 NamedDecl *New; 1410 1411 QualType R = GetTypeForDeclarator(D, S); 1412 1413 // See if this is a redefinition of a variable in the same scope. 1414 if (D.getCXXScopeSpec().isInvalid()) { 1415 DC = CurContext; 1416 PrevDecl = 0; 1417 D.setInvalidType(); 1418 } else if (!D.getCXXScopeSpec().isSet()) { 1419 LookupNameKind NameKind = LookupOrdinaryName; 1420 1421 // If the declaration we're planning to build will be a function 1422 // or object with linkage, then look for another declaration with 1423 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1424 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1425 /* Do nothing*/; 1426 else if (R->isFunctionType()) { 1427 if (CurContext->isFunctionOrMethod()) 1428 NameKind = LookupRedeclarationWithLinkage; 1429 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1430 NameKind = LookupRedeclarationWithLinkage; 1431 1432 DC = CurContext; 1433 PrevDecl = LookupName(S, Name, NameKind, true, 1434 D.getDeclSpec().getStorageClassSpec() != 1435 DeclSpec::SCS_static, 1436 D.getIdentifierLoc()); 1437 } else { // Something like "int foo::x;" 1438 DC = computeDeclContext(D.getCXXScopeSpec()); 1439 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1440 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1441 1442 // C++ 7.3.1.2p2: 1443 // Members (including explicit specializations of templates) of a named 1444 // namespace can also be defined outside that namespace by explicit 1445 // qualification of the name being defined, provided that the entity being 1446 // defined was already declared in the namespace and the definition appears 1447 // after the point of declaration in a namespace that encloses the 1448 // declarations namespace. 1449 // 1450 // Note that we only check the context at this point. We don't yet 1451 // have enough information to make sure that PrevDecl is actually 1452 // the declaration we want to match. For example, given: 1453 // 1454 // class X { 1455 // void f(); 1456 // void f(float); 1457 // }; 1458 // 1459 // void X::f(int) { } // ill-formed 1460 // 1461 // In this case, PrevDecl will point to the overload set 1462 // containing the two f's declared in X, but neither of them 1463 // matches. 1464 1465 // First check whether we named the global scope. 1466 if (isa<TranslationUnitDecl>(DC)) { 1467 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1468 << Name << D.getCXXScopeSpec().getRange(); 1469 } else if (!CurContext->Encloses(DC)) { 1470 // The qualifying scope doesn't enclose the original declaration. 1471 // Emit diagnostic based on current scope. 1472 SourceLocation L = D.getIdentifierLoc(); 1473 SourceRange R = D.getCXXScopeSpec().getRange(); 1474 if (isa<FunctionDecl>(CurContext)) 1475 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1476 else 1477 Diag(L, diag::err_invalid_declarator_scope) 1478 << Name << cast<NamedDecl>(DC) << R; 1479 D.setInvalidType(); 1480 } 1481 } 1482 1483 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1484 // Maybe we will complain about the shadowed template parameter. 1485 if (!D.isInvalidType()) 1486 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1487 D.setInvalidType(); 1488 1489 // Just pretend that we didn't see the previous declaration. 1490 PrevDecl = 0; 1491 } 1492 1493 // In C++, the previous declaration we find might be a tag type 1494 // (class or enum). In this case, the new declaration will hide the 1495 // tag type. Note that this does does not apply if we're declaring a 1496 // typedef (C++ [dcl.typedef]p4). 1497 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1498 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1499 PrevDecl = 0; 1500 1501 bool Redeclaration = false; 1502 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1503 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1504 } else if (R->isFunctionType()) { 1505 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1506 IsFunctionDefinition, Redeclaration); 1507 } else { 1508 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1509 } 1510 1511 if (New == 0) 1512 return DeclPtrTy(); 1513 1514 // If this has an identifier and is not an invalid redeclaration, 1515 // add it to the scope stack. 1516 if (Name && !(Redeclaration && New->isInvalidDecl())) 1517 PushOnScopeChains(New, S); 1518 1519 return DeclPtrTy::make(New); 1520} 1521 1522/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1523/// types into constant array types in certain situations which would otherwise 1524/// be errors (for GCC compatibility). 1525static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1526 ASTContext &Context, 1527 bool &SizeIsNegative) { 1528 // This method tries to turn a variable array into a constant 1529 // array even when the size isn't an ICE. This is necessary 1530 // for compatibility with code that depends on gcc's buggy 1531 // constant expression folding, like struct {char x[(int)(char*)2];} 1532 SizeIsNegative = false; 1533 1534 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1535 QualType Pointee = PTy->getPointeeType(); 1536 QualType FixedType = 1537 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1538 if (FixedType.isNull()) return FixedType; 1539 FixedType = Context.getPointerType(FixedType); 1540 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1541 return FixedType; 1542 } 1543 1544 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1545 if (!VLATy) 1546 return QualType(); 1547 // FIXME: We should probably handle this case 1548 if (VLATy->getElementType()->isVariablyModifiedType()) 1549 return QualType(); 1550 1551 Expr::EvalResult EvalResult; 1552 if (!VLATy->getSizeExpr() || 1553 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1554 !EvalResult.Val.isInt()) 1555 return QualType(); 1556 1557 llvm::APSInt &Res = EvalResult.Val.getInt(); 1558 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1559 return Context.getConstantArrayType(VLATy->getElementType(), 1560 Res, ArrayType::Normal, 0); 1561 1562 SizeIsNegative = true; 1563 return QualType(); 1564} 1565 1566/// \brief Register the given locally-scoped external C declaration so 1567/// that it can be found later for redeclarations 1568void 1569Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1570 Scope *S) { 1571 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1572 "Decl is not a locally-scoped decl!"); 1573 // Note that we have a locally-scoped external with this name. 1574 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1575 1576 if (!PrevDecl) 1577 return; 1578 1579 // If there was a previous declaration of this variable, it may be 1580 // in our identifier chain. Update the identifier chain with the new 1581 // declaration. 1582 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1583 // The previous declaration was found on the identifer resolver 1584 // chain, so remove it from its scope. 1585 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1586 S = S->getParent(); 1587 1588 if (S) 1589 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1590 } 1591} 1592 1593/// \brief Diagnose function specifiers on a declaration of an identifier that 1594/// does not identify a function. 1595void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1596 // FIXME: We should probably indicate the identifier in question to avoid 1597 // confusion for constructs like "inline int a(), b;" 1598 if (D.getDeclSpec().isInlineSpecified()) 1599 Diag(D.getDeclSpec().getInlineSpecLoc(), 1600 diag::err_inline_non_function); 1601 1602 if (D.getDeclSpec().isVirtualSpecified()) 1603 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1604 diag::err_virtual_non_function); 1605 1606 if (D.getDeclSpec().isExplicitSpecified()) 1607 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1608 diag::err_explicit_non_function); 1609} 1610 1611NamedDecl* 1612Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1613 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1614 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1615 if (D.getCXXScopeSpec().isSet()) { 1616 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1617 << D.getCXXScopeSpec().getRange(); 1618 D.setInvalidType(); 1619 // Pretend we didn't see the scope specifier. 1620 DC = 0; 1621 } 1622 1623 if (getLangOptions().CPlusPlus) { 1624 // Check that there are no default arguments (C++ only). 1625 CheckExtraCXXDefaultArguments(D); 1626 } 1627 1628 DiagnoseFunctionSpecifiers(D); 1629 1630 if (D.getDeclSpec().isThreadSpecified()) 1631 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1632 1633 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1634 if (!NewTD) return 0; 1635 1636 if (D.isInvalidType()) 1637 NewTD->setInvalidDecl(); 1638 1639 // Handle attributes prior to checking for duplicates in MergeVarDecl 1640 ProcessDeclAttributes(S, NewTD, D); 1641 // Merge the decl with the existing one if appropriate. If the decl is 1642 // in an outer scope, it isn't the same thing. 1643 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1644 Redeclaration = true; 1645 MergeTypeDefDecl(NewTD, PrevDecl); 1646 } 1647 1648 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1649 // then it shall have block scope. 1650 QualType T = NewTD->getUnderlyingType(); 1651 if (T->isVariablyModifiedType()) { 1652 CurFunctionNeedsScopeChecking = true; 1653 1654 if (S->getFnParent() == 0) { 1655 bool SizeIsNegative; 1656 QualType FixedTy = 1657 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1658 if (!FixedTy.isNull()) { 1659 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1660 NewTD->setUnderlyingType(FixedTy); 1661 } else { 1662 if (SizeIsNegative) 1663 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1664 else if (T->isVariableArrayType()) 1665 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1666 else 1667 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1668 NewTD->setInvalidDecl(); 1669 } 1670 } 1671 } 1672 return NewTD; 1673} 1674 1675/// \brief Determines whether the given declaration is an out-of-scope 1676/// previous declaration. 1677/// 1678/// This routine should be invoked when name lookup has found a 1679/// previous declaration (PrevDecl) that is not in the scope where a 1680/// new declaration by the same name is being introduced. If the new 1681/// declaration occurs in a local scope, previous declarations with 1682/// linkage may still be considered previous declarations (C99 1683/// 6.2.2p4-5, C++ [basic.link]p6). 1684/// 1685/// \param PrevDecl the previous declaration found by name 1686/// lookup 1687/// 1688/// \param DC the context in which the new declaration is being 1689/// declared. 1690/// 1691/// \returns true if PrevDecl is an out-of-scope previous declaration 1692/// for a new delcaration with the same name. 1693static bool 1694isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1695 ASTContext &Context) { 1696 if (!PrevDecl) 1697 return 0; 1698 1699 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1700 // case we need to check each of the overloaded functions. 1701 if (!PrevDecl->hasLinkage()) 1702 return false; 1703 1704 if (Context.getLangOptions().CPlusPlus) { 1705 // C++ [basic.link]p6: 1706 // If there is a visible declaration of an entity with linkage 1707 // having the same name and type, ignoring entities declared 1708 // outside the innermost enclosing namespace scope, the block 1709 // scope declaration declares that same entity and receives the 1710 // linkage of the previous declaration. 1711 DeclContext *OuterContext = DC->getLookupContext(); 1712 if (!OuterContext->isFunctionOrMethod()) 1713 // This rule only applies to block-scope declarations. 1714 return false; 1715 else { 1716 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1717 if (PrevOuterContext->isRecord()) 1718 // We found a member function: ignore it. 1719 return false; 1720 else { 1721 // Find the innermost enclosing namespace for the new and 1722 // previous declarations. 1723 while (!OuterContext->isFileContext()) 1724 OuterContext = OuterContext->getParent(); 1725 while (!PrevOuterContext->isFileContext()) 1726 PrevOuterContext = PrevOuterContext->getParent(); 1727 1728 // The previous declaration is in a different namespace, so it 1729 // isn't the same function. 1730 if (OuterContext->getPrimaryContext() != 1731 PrevOuterContext->getPrimaryContext()) 1732 return false; 1733 } 1734 } 1735 } 1736 1737 return true; 1738} 1739 1740NamedDecl* 1741Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1742 QualType R,NamedDecl* PrevDecl, 1743 bool &Redeclaration) { 1744 DeclarationName Name = GetNameForDeclarator(D); 1745 1746 // Check that there are no default arguments (C++ only). 1747 if (getLangOptions().CPlusPlus) 1748 CheckExtraCXXDefaultArguments(D); 1749 1750 VarDecl *NewVD; 1751 VarDecl::StorageClass SC; 1752 switch (D.getDeclSpec().getStorageClassSpec()) { 1753 default: assert(0 && "Unknown storage class!"); 1754 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1755 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1756 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1757 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1758 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1759 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1760 case DeclSpec::SCS_mutable: 1761 // mutable can only appear on non-static class members, so it's always 1762 // an error here 1763 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1764 D.setInvalidType(); 1765 SC = VarDecl::None; 1766 break; 1767 } 1768 1769 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1770 if (!II) { 1771 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1772 << Name.getAsString(); 1773 return 0; 1774 } 1775 1776 DiagnoseFunctionSpecifiers(D); 1777 1778 if (!DC->isRecord() && S->getFnParent() == 0) { 1779 // C99 6.9p2: The storage-class specifiers auto and register shall not 1780 // appear in the declaration specifiers in an external declaration. 1781 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1782 1783 // If this is a register variable with an asm label specified, then this 1784 // is a GNU extension. 1785 if (SC == VarDecl::Register && D.getAsmLabel()) 1786 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 1787 else 1788 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1789 D.setInvalidType(); 1790 } 1791 } 1792 if (DC->isRecord() && !CurContext->isRecord()) { 1793 // This is an out-of-line definition of a static data member. 1794 if (SC == VarDecl::Static) { 1795 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1796 diag::err_static_out_of_line) 1797 << CodeModificationHint::CreateRemoval( 1798 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1799 } else if (SC == VarDecl::None) 1800 SC = VarDecl::Static; 1801 } 1802 1803 // The variable can not 1804 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1805 II, R, SC, 1806 // FIXME: Move to DeclGroup... 1807 D.getDeclSpec().getSourceRange().getBegin()); 1808 1809 if (D.isInvalidType()) 1810 NewVD->setInvalidDecl(); 1811 1812 if (D.getDeclSpec().isThreadSpecified()) { 1813 if (NewVD->hasLocalStorage()) 1814 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1815 else if (!Context.Target.isTLSSupported()) 1816 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1817 else 1818 NewVD->setThreadSpecified(true); 1819 } 1820 1821 // Set the lexical context. If the declarator has a C++ scope specifier, the 1822 // lexical context will be different from the semantic context. 1823 NewVD->setLexicalDeclContext(CurContext); 1824 1825 // Handle attributes prior to checking for duplicates in MergeVarDecl 1826 ProcessDeclAttributes(S, NewVD, D); 1827 1828 // Handle GNU asm-label extension (encoded as an attribute). 1829 if (Expr *E = (Expr*) D.getAsmLabel()) { 1830 // The parser guarantees this is a string. 1831 StringLiteral *SE = cast<StringLiteral>(E); 1832 NewVD->addAttr(Context, 1833 ::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1834 SE->getByteLength()))); 1835 } 1836 1837 // If name lookup finds a previous declaration that is not in the 1838 // same scope as the new declaration, this may still be an 1839 // acceptable redeclaration. 1840 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1841 !(NewVD->hasLinkage() && 1842 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1843 PrevDecl = 0; 1844 1845 // Merge the decl with the existing one if appropriate. 1846 if (PrevDecl) { 1847 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1848 // The user tried to define a non-static data member 1849 // out-of-line (C++ [dcl.meaning]p1). 1850 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1851 << D.getCXXScopeSpec().getRange(); 1852 PrevDecl = 0; 1853 NewVD->setInvalidDecl(); 1854 } 1855 } else if (D.getCXXScopeSpec().isSet()) { 1856 // No previous declaration in the qualifying scope. 1857 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1858 << Name << D.getCXXScopeSpec().getRange(); 1859 NewVD->setInvalidDecl(); 1860 } 1861 1862 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1863 1864 // If this is a locally-scoped extern C variable, update the map of 1865 // such variables. 1866 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1867 !NewVD->isInvalidDecl()) 1868 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1869 1870 return NewVD; 1871} 1872 1873/// \brief Perform semantic checking on a newly-created variable 1874/// declaration. 1875/// 1876/// This routine performs all of the type-checking required for a 1877/// variable declaration once it has been built. It is used both to 1878/// check variables after they have been parsed and their declarators 1879/// have been translated into a declaration, and to check variables 1880/// that have been instantiated from a template. 1881/// 1882/// Sets NewVD->isInvalidDecl() if an error was encountered. 1883void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1884 bool &Redeclaration) { 1885 // If the decl is already known invalid, don't check it. 1886 if (NewVD->isInvalidDecl()) 1887 return; 1888 1889 QualType T = NewVD->getType(); 1890 1891 if (T->isObjCInterfaceType()) { 1892 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1893 return NewVD->setInvalidDecl(); 1894 } 1895 1896 // The variable can not have an abstract class type. 1897 if (RequireNonAbstractType(NewVD->getLocation(), T, 1898 diag::err_abstract_type_in_decl, 1899 AbstractVariableType)) 1900 return NewVD->setInvalidDecl(); 1901 1902 // Emit an error if an address space was applied to decl with local storage. 1903 // This includes arrays of objects with address space qualifiers, but not 1904 // automatic variables that point to other address spaces. 1905 // ISO/IEC TR 18037 S5.1.2 1906 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1907 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1908 return NewVD->setInvalidDecl(); 1909 } 1910 1911 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1912 && !NewVD->hasAttr<BlocksAttr>(Context)) 1913 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1914 1915 bool isVM = T->isVariablyModifiedType(); 1916 if (isVM || NewVD->hasAttr<CleanupAttr>(Context)) 1917 CurFunctionNeedsScopeChecking = true; 1918 1919 if ((isVM && NewVD->hasLinkage()) || 1920 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1921 bool SizeIsNegative; 1922 QualType FixedTy = 1923 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1924 1925 if (FixedTy.isNull() && T->isVariableArrayType()) { 1926 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1927 // FIXME: This won't give the correct result for 1928 // int a[10][n]; 1929 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1930 1931 if (NewVD->isFileVarDecl()) 1932 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1933 << SizeRange; 1934 else if (NewVD->getStorageClass() == VarDecl::Static) 1935 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1936 << SizeRange; 1937 else 1938 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1939 << SizeRange; 1940 return NewVD->setInvalidDecl(); 1941 } 1942 1943 if (FixedTy.isNull()) { 1944 if (NewVD->isFileVarDecl()) 1945 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1946 else 1947 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1948 return NewVD->setInvalidDecl(); 1949 } 1950 1951 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1952 NewVD->setType(FixedTy); 1953 } 1954 1955 if (!PrevDecl && NewVD->isExternC(Context)) { 1956 // Since we did not find anything by this name and we're declaring 1957 // an extern "C" variable, look for a non-visible extern "C" 1958 // declaration with the same name. 1959 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1960 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1961 if (Pos != LocallyScopedExternalDecls.end()) 1962 PrevDecl = Pos->second; 1963 } 1964 1965 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1966 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1967 << T; 1968 return NewVD->setInvalidDecl(); 1969 } 1970 1971 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>(Context)) { 1972 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 1973 return NewVD->setInvalidDecl(); 1974 } 1975 1976 if (isVM && NewVD->hasAttr<BlocksAttr>(Context)) { 1977 Diag(NewVD->getLocation(), diag::err_block_on_vm); 1978 return NewVD->setInvalidDecl(); 1979 } 1980 1981 if (PrevDecl) { 1982 Redeclaration = true; 1983 MergeVarDecl(NewVD, PrevDecl); 1984 } 1985} 1986 1987NamedDecl* 1988Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1989 QualType R, NamedDecl* PrevDecl, 1990 bool IsFunctionDefinition, bool &Redeclaration) { 1991 assert(R.getTypePtr()->isFunctionType()); 1992 1993 DeclarationName Name = GetNameForDeclarator(D); 1994 FunctionDecl::StorageClass SC = FunctionDecl::None; 1995 switch (D.getDeclSpec().getStorageClassSpec()) { 1996 default: assert(0 && "Unknown storage class!"); 1997 case DeclSpec::SCS_auto: 1998 case DeclSpec::SCS_register: 1999 case DeclSpec::SCS_mutable: 2000 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2001 diag::err_typecheck_sclass_func); 2002 D.setInvalidType(); 2003 break; 2004 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2005 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2006 case DeclSpec::SCS_static: { 2007 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2008 // C99 6.7.1p5: 2009 // The declaration of an identifier for a function that has 2010 // block scope shall have no explicit storage-class specifier 2011 // other than extern 2012 // See also (C++ [dcl.stc]p4). 2013 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2014 diag::err_static_block_func); 2015 SC = FunctionDecl::None; 2016 } else 2017 SC = FunctionDecl::Static; 2018 break; 2019 } 2020 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2021 } 2022 2023 if (D.getDeclSpec().isThreadSpecified()) 2024 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2025 2026 bool isInline = D.getDeclSpec().isInlineSpecified(); 2027 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2028 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2029 2030 // Check that the return type is not an abstract class type. 2031 // For record types, this is done by the AbstractClassUsageDiagnoser once 2032 // the class has been completely parsed. 2033 if (!DC->isRecord() && 2034 RequireNonAbstractType(D.getIdentifierLoc(), 2035 R->getAsFunctionType()->getResultType(), 2036 diag::err_abstract_type_in_decl, 2037 AbstractReturnType)) 2038 D.setInvalidType(); 2039 2040 // Do not allow returning a objc interface by-value. 2041 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 2042 Diag(D.getIdentifierLoc(), 2043 diag::err_object_cannot_be_passed_returned_by_value) << 0 2044 << R->getAsFunctionType()->getResultType(); 2045 D.setInvalidType(); 2046 } 2047 2048 bool isVirtualOkay = false; 2049 FunctionDecl *NewFD; 2050 if (D.getKind() == Declarator::DK_Constructor) { 2051 // This is a C++ constructor declaration. 2052 assert(DC->isRecord() && 2053 "Constructors can only be declared in a member context"); 2054 2055 R = CheckConstructorDeclarator(D, R, SC); 2056 2057 // Create the new declaration 2058 NewFD = CXXConstructorDecl::Create(Context, 2059 cast<CXXRecordDecl>(DC), 2060 D.getIdentifierLoc(), Name, R, 2061 isExplicit, isInline, 2062 /*isImplicitlyDeclared=*/false); 2063 } else if (D.getKind() == Declarator::DK_Destructor) { 2064 // This is a C++ destructor declaration. 2065 if (DC->isRecord()) { 2066 R = CheckDestructorDeclarator(D, SC); 2067 2068 NewFD = CXXDestructorDecl::Create(Context, 2069 cast<CXXRecordDecl>(DC), 2070 D.getIdentifierLoc(), Name, R, 2071 isInline, 2072 /*isImplicitlyDeclared=*/false); 2073 2074 isVirtualOkay = true; 2075 } else { 2076 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2077 2078 // Create a FunctionDecl to satisfy the function definition parsing 2079 // code path. 2080 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2081 Name, R, SC, isInline, 2082 /*hasPrototype=*/true, 2083 // FIXME: Move to DeclGroup... 2084 D.getDeclSpec().getSourceRange().getBegin()); 2085 D.setInvalidType(); 2086 } 2087 } else if (D.getKind() == Declarator::DK_Conversion) { 2088 if (!DC->isRecord()) { 2089 Diag(D.getIdentifierLoc(), 2090 diag::err_conv_function_not_member); 2091 return 0; 2092 } 2093 2094 CheckConversionDeclarator(D, R, SC); 2095 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2096 D.getIdentifierLoc(), Name, R, 2097 isInline, isExplicit); 2098 2099 isVirtualOkay = true; 2100 } else if (DC->isRecord()) { 2101 // If the of the function is the same as the name of the record, then this 2102 // must be an invalid constructor that has a return type. 2103 // (The parser checks for a return type and makes the declarator a 2104 // constructor if it has no return type). 2105 // must have an invalid constructor that has a return type 2106 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2107 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2108 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2109 << SourceRange(D.getIdentifierLoc()); 2110 return 0; 2111 } 2112 2113 // This is a C++ method declaration. 2114 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2115 D.getIdentifierLoc(), Name, R, 2116 (SC == FunctionDecl::Static), isInline); 2117 2118 isVirtualOkay = (SC != FunctionDecl::Static); 2119 } else { 2120 // Determine whether the function was written with a 2121 // prototype. This true when: 2122 // - we're in C++ (where every function has a prototype), 2123 // - there is a prototype in the declarator, or 2124 // - the type R of the function is some kind of typedef or other reference 2125 // to a type name (which eventually refers to a function type). 2126 bool HasPrototype = 2127 getLangOptions().CPlusPlus || 2128 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2129 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2130 2131 NewFD = FunctionDecl::Create(Context, DC, 2132 D.getIdentifierLoc(), 2133 Name, R, SC, isInline, HasPrototype, 2134 // FIXME: Move to DeclGroup... 2135 D.getDeclSpec().getSourceRange().getBegin()); 2136 } 2137 2138 if (D.isInvalidType()) 2139 NewFD->setInvalidDecl(); 2140 2141 // Set the lexical context. If the declarator has a C++ 2142 // scope specifier, the lexical context will be different 2143 // from the semantic context. 2144 NewFD->setLexicalDeclContext(CurContext); 2145 2146 // C++ [dcl.fct.spec]p5: 2147 // The virtual specifier shall only be used in declarations of 2148 // nonstatic class member functions that appear within a 2149 // member-specification of a class declaration; see 10.3. 2150 // 2151 if (isVirtual && !NewFD->isInvalidDecl()) { 2152 if (!isVirtualOkay) { 2153 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2154 diag::err_virtual_non_function); 2155 } else if (!CurContext->isRecord()) { 2156 // 'virtual' was specified outside of the class. 2157 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2158 << CodeModificationHint::CreateRemoval( 2159 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2160 } else { 2161 // Okay: Add virtual to the method. 2162 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2163 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2164 CurClass->setAggregate(false); 2165 CurClass->setPOD(false); 2166 CurClass->setPolymorphic(true); 2167 CurClass->setHasTrivialConstructor(false); 2168 } 2169 } 2170 2171 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2172 // Look for virtual methods in base classes that this method might override. 2173 2174 BasePaths Paths; 2175 if (LookupInBases(cast<CXXRecordDecl>(DC), 2176 MemberLookupCriteria(NewMD), Paths)) { 2177 for (BasePaths::decl_iterator I = Paths.found_decls_begin(), 2178 E = Paths.found_decls_end(); I != E; ++I) { 2179 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2180 if (!CheckOverridingFunctionReturnType(NewMD, OldMD)) 2181 NewMD->addOverriddenMethod(OldMD); 2182 } 2183 } 2184 } 2185 } 2186 2187 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2188 !CurContext->isRecord()) { 2189 // C++ [class.static]p1: 2190 // A data or function member of a class may be declared static 2191 // in a class definition, in which case it is a static member of 2192 // the class. 2193 2194 // Complain about the 'static' specifier if it's on an out-of-line 2195 // member function definition. 2196 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2197 diag::err_static_out_of_line) 2198 << CodeModificationHint::CreateRemoval( 2199 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2200 } 2201 2202 // Handle GNU asm-label extension (encoded as an attribute). 2203 if (Expr *E = (Expr*) D.getAsmLabel()) { 2204 // The parser guarantees this is a string. 2205 StringLiteral *SE = cast<StringLiteral>(E); 2206 NewFD->addAttr(Context, 2207 ::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2208 SE->getByteLength()))); 2209 } 2210 2211 // Copy the parameter declarations from the declarator D to the function 2212 // declaration NewFD, if they are available. First scavenge them into Params. 2213 llvm::SmallVector<ParmVarDecl*, 16> Params; 2214 if (D.getNumTypeObjects() > 0) { 2215 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2216 2217 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2218 // function that takes no arguments, not a function that takes a 2219 // single void argument. 2220 // We let through "const void" here because Sema::GetTypeForDeclarator 2221 // already checks for that case. 2222 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2223 FTI.ArgInfo[0].Param && 2224 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2225 // Empty arg list, don't push any params. 2226 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2227 2228 // In C++, the empty parameter-type-list must be spelled "void"; a 2229 // typedef of void is not permitted. 2230 if (getLangOptions().CPlusPlus && 2231 Param->getType().getUnqualifiedType() != Context.VoidTy) 2232 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2233 // FIXME: Leaks decl? 2234 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2235 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2236 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2237 } 2238 2239 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2240 // When we're declaring a function with a typedef, typeof, etc as in the 2241 // following example, we'll need to synthesize (unnamed) 2242 // parameters for use in the declaration. 2243 // 2244 // @code 2245 // typedef void fn(int); 2246 // fn f; 2247 // @endcode 2248 2249 // Synthesize a parameter for each argument type. 2250 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2251 AE = FT->arg_type_end(); AI != AE; ++AI) { 2252 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2253 SourceLocation(), 0, 2254 *AI, VarDecl::None, 0); 2255 Param->setImplicit(); 2256 Params.push_back(Param); 2257 } 2258 } else { 2259 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2260 "Should not need args for typedef of non-prototype fn"); 2261 } 2262 // Finally, we know we have the right number of parameters, install them. 2263 NewFD->setParams(Context, Params.data(), Params.size()); 2264 2265 2266 2267 // If name lookup finds a previous declaration that is not in the 2268 // same scope as the new declaration, this may still be an 2269 // acceptable redeclaration. 2270 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2271 !(NewFD->hasLinkage() && 2272 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2273 PrevDecl = 0; 2274 2275 // Perform semantic checking on the function declaration. 2276 bool OverloadableAttrRequired = false; // FIXME: HACK! 2277 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2278 /*FIXME:*/OverloadableAttrRequired); 2279 2280 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2281 // An out-of-line member function declaration must also be a 2282 // definition (C++ [dcl.meaning]p1). 2283 if (!IsFunctionDefinition) { 2284 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2285 << D.getCXXScopeSpec().getRange(); 2286 NewFD->setInvalidDecl(); 2287 } else if (!Redeclaration) { 2288 // The user tried to provide an out-of-line definition for a 2289 // function that is a member of a class or namespace, but there 2290 // was no such member function declared (C++ [class.mfct]p2, 2291 // C++ [namespace.memdef]p2). For example: 2292 // 2293 // class X { 2294 // void f() const; 2295 // }; 2296 // 2297 // void X::f() { } // ill-formed 2298 // 2299 // Complain about this problem, and attempt to suggest close 2300 // matches (e.g., those that differ only in cv-qualifiers and 2301 // whether the parameter types are references). 2302 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2303 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2304 NewFD->setInvalidDecl(); 2305 2306 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2307 true); 2308 assert(!Prev.isAmbiguous() && 2309 "Cannot have an ambiguity in previous-declaration lookup"); 2310 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2311 Func != FuncEnd; ++Func) { 2312 if (isa<FunctionDecl>(*Func) && 2313 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2314 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2315 } 2316 2317 PrevDecl = 0; 2318 } 2319 } 2320 2321 // Handle attributes. We need to have merged decls when handling attributes 2322 // (for example to check for conflicts, etc). 2323 // FIXME: This needs to happen before we merge declarations. Then, 2324 // let attribute merging cope with attribute conflicts. 2325 ProcessDeclAttributes(S, NewFD, D); 2326 AddKnownFunctionAttributes(NewFD); 2327 2328 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>(Context)) { 2329 // If a function name is overloadable in C, then every function 2330 // with that name must be marked "overloadable". 2331 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2332 << Redeclaration << NewFD; 2333 if (PrevDecl) 2334 Diag(PrevDecl->getLocation(), 2335 diag::note_attribute_overloadable_prev_overload); 2336 NewFD->addAttr(Context, ::new (Context) OverloadableAttr()); 2337 } 2338 2339 // If this is a locally-scoped extern C function, update the 2340 // map of such names. 2341 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2342 && !NewFD->isInvalidDecl()) 2343 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2344 2345 return NewFD; 2346} 2347 2348/// \brief Perform semantic checking of a new function declaration. 2349/// 2350/// Performs semantic analysis of the new function declaration 2351/// NewFD. This routine performs all semantic checking that does not 2352/// require the actual declarator involved in the declaration, and is 2353/// used both for the declaration of functions as they are parsed 2354/// (called via ActOnDeclarator) and for the declaration of functions 2355/// that have been instantiated via C++ template instantiation (called 2356/// via InstantiateDecl). 2357/// 2358/// This sets NewFD->isInvalidDecl() to true if there was an error. 2359void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2360 bool &Redeclaration, 2361 bool &OverloadableAttrRequired) { 2362 // If NewFD is already known erroneous, don't do any of this checking. 2363 if (NewFD->isInvalidDecl()) 2364 return; 2365 2366 if (NewFD->getResultType()->isVariablyModifiedType()) { 2367 // Functions returning a variably modified type violate C99 6.7.5.2p2 2368 // because all functions have linkage. 2369 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 2370 return NewFD->setInvalidDecl(); 2371 } 2372 2373 // Semantic checking for this function declaration (in isolation). 2374 if (getLangOptions().CPlusPlus) { 2375 // C++-specific checks. 2376 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2377 CheckConstructor(Constructor); 2378 } else if (isa<CXXDestructorDecl>(NewFD)) { 2379 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2380 Record->setUserDeclaredDestructor(true); 2381 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2382 // user-defined destructor. 2383 Record->setPOD(false); 2384 2385 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2386 // declared destructor. 2387 Record->setHasTrivialDestructor(false); 2388 } else if (CXXConversionDecl *Conversion 2389 = dyn_cast<CXXConversionDecl>(NewFD)) 2390 ActOnConversionDeclarator(Conversion); 2391 2392 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2393 if (NewFD->isOverloadedOperator() && 2394 CheckOverloadedOperatorDeclaration(NewFD)) 2395 return NewFD->setInvalidDecl(); 2396 } 2397 2398 // C99 6.7.4p6: 2399 // [... ] For a function with external linkage, the following 2400 // restrictions apply: [...] If all of the file scope declarations 2401 // for a function in a translation unit include the inline 2402 // function specifier without extern, then the definition in that 2403 // translation unit is an inline definition. An inline definition 2404 // does not provide an external definition for the function, and 2405 // does not forbid an external definition in another translation 2406 // unit. 2407 // 2408 // Here we determine whether this function, in isolation, would be a 2409 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2410 // previous declarations. 2411 if (NewFD->isInline() && getLangOptions().C99 && 2412 NewFD->getStorageClass() == FunctionDecl::None && 2413 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2414 NewFD->setC99InlineDefinition(true); 2415 2416 // Check for a previous declaration of this name. 2417 if (!PrevDecl && NewFD->isExternC(Context)) { 2418 // Since we did not find anything by this name and we're declaring 2419 // an extern "C" function, look for a non-visible extern "C" 2420 // declaration with the same name. 2421 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2422 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2423 if (Pos != LocallyScopedExternalDecls.end()) 2424 PrevDecl = Pos->second; 2425 } 2426 2427 // Merge or overload the declaration with an existing declaration of 2428 // the same name, if appropriate. 2429 if (PrevDecl) { 2430 // Determine whether NewFD is an overload of PrevDecl or 2431 // a declaration that requires merging. If it's an overload, 2432 // there's no more work to do here; we'll just add the new 2433 // function to the scope. 2434 OverloadedFunctionDecl::function_iterator MatchedDecl; 2435 2436 if (!getLangOptions().CPlusPlus && 2437 AllowOverloadingOfFunction(PrevDecl, Context)) { 2438 OverloadableAttrRequired = true; 2439 2440 // Functions marked "overloadable" must have a prototype (that 2441 // we can't get through declaration merging). 2442 if (!NewFD->getType()->getAsFunctionProtoType()) { 2443 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2444 << NewFD; 2445 Redeclaration = true; 2446 2447 // Turn this into a variadic function with no parameters. 2448 QualType R = Context.getFunctionType( 2449 NewFD->getType()->getAsFunctionType()->getResultType(), 2450 0, 0, true, 0); 2451 NewFD->setType(R); 2452 return NewFD->setInvalidDecl(); 2453 } 2454 } 2455 2456 if (PrevDecl && 2457 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2458 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2459 Redeclaration = true; 2460 Decl *OldDecl = PrevDecl; 2461 2462 // If PrevDecl was an overloaded function, extract the 2463 // FunctionDecl that matched. 2464 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2465 OldDecl = *MatchedDecl; 2466 2467 // NewFD and OldDecl represent declarations that need to be 2468 // merged. 2469 if (MergeFunctionDecl(NewFD, OldDecl)) 2470 return NewFD->setInvalidDecl(); 2471 2472 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2473 } 2474 } 2475 2476 // In C++, check default arguments now that we have merged decls. Unless 2477 // the lexical context is the class, because in this case this is done 2478 // during delayed parsing anyway. 2479 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2480 CheckCXXDefaultArguments(NewFD); 2481} 2482 2483bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2484 // FIXME: Need strict checking. In C89, we need to check for 2485 // any assignment, increment, decrement, function-calls, or 2486 // commas outside of a sizeof. In C99, it's the same list, 2487 // except that the aforementioned are allowed in unevaluated 2488 // expressions. Everything else falls under the 2489 // "may accept other forms of constant expressions" exception. 2490 // (We never end up here for C++, so the constant expression 2491 // rules there don't matter.) 2492 if (Init->isConstantInitializer(Context)) 2493 return false; 2494 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2495 << Init->getSourceRange(); 2496 return true; 2497} 2498 2499void Sema::AddInitializerToDecl(DeclPtrTy dcl, FullExprArg init) { 2500 AddInitializerToDecl(dcl, init.release(), /*DirectInit=*/false); 2501} 2502 2503/// AddInitializerToDecl - Adds the initializer Init to the 2504/// declaration dcl. If DirectInit is true, this is C++ direct 2505/// initialization rather than copy initialization. 2506void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2507 Decl *RealDecl = dcl.getAs<Decl>(); 2508 // If there is no declaration, there was an error parsing it. Just ignore 2509 // the initializer. 2510 if (RealDecl == 0) 2511 return; 2512 2513 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2514 // With declarators parsed the way they are, the parser cannot 2515 // distinguish between a normal initializer and a pure-specifier. 2516 // Thus this grotesque test. 2517 IntegerLiteral *IL; 2518 Expr *Init = static_cast<Expr *>(init.get()); 2519 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2520 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2521 if (Method->isVirtualAsWritten()) { 2522 Method->setPure(); 2523 2524 // A class is abstract if at least one function is pure virtual. 2525 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2526 } else if (!Method->isInvalidDecl()) { 2527 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2528 << Method->getDeclName() << Init->getSourceRange(); 2529 Method->setInvalidDecl(); 2530 } 2531 } else { 2532 Diag(Method->getLocation(), diag::err_member_function_initialization) 2533 << Method->getDeclName() << Init->getSourceRange(); 2534 Method->setInvalidDecl(); 2535 } 2536 return; 2537 } 2538 2539 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2540 if (!VDecl) { 2541 if (getLangOptions().CPlusPlus && 2542 RealDecl->getLexicalDeclContext()->isRecord() && 2543 isa<NamedDecl>(RealDecl)) 2544 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2545 << cast<NamedDecl>(RealDecl)->getDeclName(); 2546 else 2547 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2548 RealDecl->setInvalidDecl(); 2549 return; 2550 } 2551 2552 if (!VDecl->getType()->isArrayType() && 2553 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2554 diag::err_typecheck_decl_incomplete_type)) { 2555 RealDecl->setInvalidDecl(); 2556 return; 2557 } 2558 2559 const VarDecl *Def = 0; 2560 if (VDecl->getDefinition(Def)) { 2561 Diag(VDecl->getLocation(), diag::err_redefinition) 2562 << VDecl->getDeclName(); 2563 Diag(Def->getLocation(), diag::note_previous_definition); 2564 VDecl->setInvalidDecl(); 2565 return; 2566 } 2567 2568 // Take ownership of the expression, now that we're sure we have somewhere 2569 // to put it. 2570 Expr *Init = init.takeAs<Expr>(); 2571 assert(Init && "missing initializer"); 2572 2573 // Get the decls type and save a reference for later, since 2574 // CheckInitializerTypes may change it. 2575 QualType DclT = VDecl->getType(), SavT = DclT; 2576 if (VDecl->isBlockVarDecl()) { 2577 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2578 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2579 VDecl->setInvalidDecl(); 2580 } else if (!VDecl->isInvalidDecl()) { 2581 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2582 VDecl->getDeclName(), DirectInit)) 2583 VDecl->setInvalidDecl(); 2584 2585 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2586 // Don't check invalid declarations to avoid emitting useless diagnostics. 2587 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2588 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2589 CheckForConstantInitializer(Init, DclT); 2590 } 2591 } 2592 } else if (VDecl->isStaticDataMember() && 2593 VDecl->getLexicalDeclContext()->isRecord()) { 2594 // This is an in-class initialization for a static data member, e.g., 2595 // 2596 // struct S { 2597 // static const int value = 17; 2598 // }; 2599 2600 // Attach the initializer 2601 VDecl->setInit(Context, Init); 2602 2603 // C++ [class.mem]p4: 2604 // A member-declarator can contain a constant-initializer only 2605 // if it declares a static member (9.4) of const integral or 2606 // const enumeration type, see 9.4.2. 2607 QualType T = VDecl->getType(); 2608 if (!T->isDependentType() && 2609 (!Context.getCanonicalType(T).isConstQualified() || 2610 !T->isIntegralType())) { 2611 Diag(VDecl->getLocation(), diag::err_member_initialization) 2612 << VDecl->getDeclName() << Init->getSourceRange(); 2613 VDecl->setInvalidDecl(); 2614 } else { 2615 // C++ [class.static.data]p4: 2616 // If a static data member is of const integral or const 2617 // enumeration type, its declaration in the class definition 2618 // can specify a constant-initializer which shall be an 2619 // integral constant expression (5.19). 2620 if (!Init->isTypeDependent() && 2621 !Init->getType()->isIntegralType()) { 2622 // We have a non-dependent, non-integral or enumeration type. 2623 Diag(Init->getSourceRange().getBegin(), 2624 diag::err_in_class_initializer_non_integral_type) 2625 << Init->getType() << Init->getSourceRange(); 2626 VDecl->setInvalidDecl(); 2627 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2628 // Check whether the expression is a constant expression. 2629 llvm::APSInt Value; 2630 SourceLocation Loc; 2631 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2632 Diag(Loc, diag::err_in_class_initializer_non_constant) 2633 << Init->getSourceRange(); 2634 VDecl->setInvalidDecl(); 2635 } else if (!VDecl->getType()->isDependentType()) 2636 ImpCastExprToType(Init, VDecl->getType()); 2637 } 2638 } 2639 } else if (VDecl->isFileVarDecl()) { 2640 if (VDecl->getStorageClass() == VarDecl::Extern) 2641 Diag(VDecl->getLocation(), diag::warn_extern_init); 2642 if (!VDecl->isInvalidDecl()) 2643 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2644 VDecl->getDeclName(), DirectInit)) 2645 VDecl->setInvalidDecl(); 2646 2647 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2648 // Don't check invalid declarations to avoid emitting useless diagnostics. 2649 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2650 // C99 6.7.8p4. All file scoped initializers need to be constant. 2651 CheckForConstantInitializer(Init, DclT); 2652 } 2653 } 2654 // If the type changed, it means we had an incomplete type that was 2655 // completed by the initializer. For example: 2656 // int ary[] = { 1, 3, 5 }; 2657 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2658 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2659 VDecl->setType(DclT); 2660 Init->setType(DclT); 2661 } 2662 2663 // Attach the initializer to the decl. 2664 VDecl->setInit(Context, Init); 2665 2666 // If the previous declaration of VDecl was a tentative definition, 2667 // remove it from the set of tentative definitions. 2668 if (VDecl->getPreviousDeclaration() && 2669 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2670 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2671 = TentativeDefinitions.find(VDecl->getDeclName()); 2672 assert(Pos != TentativeDefinitions.end() && 2673 "Unrecorded tentative definition?"); 2674 TentativeDefinitions.erase(Pos); 2675 } 2676 2677 return; 2678} 2679 2680void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2681 Decl *RealDecl = dcl.getAs<Decl>(); 2682 2683 // If there is no declaration, there was an error parsing it. Just ignore it. 2684 if (RealDecl == 0) 2685 return; 2686 2687 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2688 QualType Type = Var->getType(); 2689 2690 // Record tentative definitions. 2691 if (Var->isTentativeDefinition(Context)) 2692 TentativeDefinitions[Var->getDeclName()] = Var; 2693 2694 // C++ [dcl.init.ref]p3: 2695 // The initializer can be omitted for a reference only in a 2696 // parameter declaration (8.3.5), in the declaration of a 2697 // function return type, in the declaration of a class member 2698 // within its class declaration (9.2), and where the extern 2699 // specifier is explicitly used. 2700 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2701 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2702 << Var->getDeclName() 2703 << SourceRange(Var->getLocation(), Var->getLocation()); 2704 Var->setInvalidDecl(); 2705 return; 2706 } 2707 2708 // C++ [dcl.init]p9: 2709 // 2710 // If no initializer is specified for an object, and the object 2711 // is of (possibly cv-qualified) non-POD class type (or array 2712 // thereof), the object shall be default-initialized; if the 2713 // object is of const-qualified type, the underlying class type 2714 // shall have a user-declared default constructor. 2715 if (getLangOptions().CPlusPlus) { 2716 QualType InitType = Type; 2717 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2718 InitType = Array->getElementType(); 2719 if ((!Var->hasExternalStorage() && !Var->isExternC(Context)) && 2720 InitType->isRecordType() && !InitType->isDependentType()) { 2721 CXXRecordDecl *RD = 2722 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2723 CXXConstructorDecl *Constructor = 0; 2724 if (!RequireCompleteType(Var->getLocation(), InitType, 2725 diag::err_invalid_incomplete_type_use)) 2726 Constructor 2727 = PerformInitializationByConstructor(InitType, 0, 0, 2728 Var->getLocation(), 2729 SourceRange(Var->getLocation(), 2730 Var->getLocation()), 2731 Var->getDeclName(), 2732 IK_Default); 2733 if (!Constructor) 2734 Var->setInvalidDecl(); 2735 else { 2736 if (!RD->hasTrivialConstructor()) 2737 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2738 // Check for valid construction. 2739 DefineImplicitDefaultConstructor(Var->getLocation(), Constructor); 2740 } 2741 } 2742 } 2743 2744#if 0 2745 // FIXME: Temporarily disabled because we are not properly parsing 2746 // linkage specifications on declarations, e.g., 2747 // 2748 // extern "C" const CGPoint CGPointerZero; 2749 // 2750 // C++ [dcl.init]p9: 2751 // 2752 // If no initializer is specified for an object, and the 2753 // object is of (possibly cv-qualified) non-POD class type (or 2754 // array thereof), the object shall be default-initialized; if 2755 // the object is of const-qualified type, the underlying class 2756 // type shall have a user-declared default 2757 // constructor. Otherwise, if no initializer is specified for 2758 // an object, the object and its subobjects, if any, have an 2759 // indeterminate initial value; if the object or any of its 2760 // subobjects are of const-qualified type, the program is 2761 // ill-formed. 2762 // 2763 // This isn't technically an error in C, so we don't diagnose it. 2764 // 2765 // FIXME: Actually perform the POD/user-defined default 2766 // constructor check. 2767 if (getLangOptions().CPlusPlus && 2768 Context.getCanonicalType(Type).isConstQualified() && 2769 !Var->hasExternalStorage()) 2770 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2771 << Var->getName() 2772 << SourceRange(Var->getLocation(), Var->getLocation()); 2773#endif 2774 } 2775} 2776 2777Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 2778 DeclPtrTy *Group, 2779 unsigned NumDecls) { 2780 llvm::SmallVector<Decl*, 8> Decls; 2781 2782 if (DS.isTypeSpecOwned()) 2783 Decls.push_back((Decl*)DS.getTypeRep()); 2784 2785 for (unsigned i = 0; i != NumDecls; ++i) 2786 if (Decl *D = Group[i].getAs<Decl>()) 2787 Decls.push_back(D); 2788 2789 // Perform semantic analysis that depends on having fully processed both 2790 // the declarator and initializer. 2791 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2792 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2793 if (!IDecl) 2794 continue; 2795 QualType T = IDecl->getType(); 2796 2797 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2798 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2799 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2800 if (!IDecl->isInvalidDecl() && 2801 RequireCompleteType(IDecl->getLocation(), T, 2802 diag::err_typecheck_decl_incomplete_type)) 2803 IDecl->setInvalidDecl(); 2804 } 2805 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2806 // object that has file scope without an initializer, and without a 2807 // storage-class specifier or with the storage-class specifier "static", 2808 // constitutes a tentative definition. Note: A tentative definition with 2809 // external linkage is valid (C99 6.2.2p5). 2810 if (IDecl->isTentativeDefinition(Context)) { 2811 QualType CheckType = T; 2812 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2813 2814 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2815 if (ArrayT) { 2816 CheckType = ArrayT->getElementType(); 2817 DiagID = diag::err_illegal_decl_array_incomplete_type; 2818 } 2819 2820 if (IDecl->isInvalidDecl()) { 2821 // Do nothing with invalid declarations 2822 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2823 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2824 // C99 6.9.2p3: If the declaration of an identifier for an object is 2825 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2826 // declared type shall not be an incomplete type. 2827 IDecl->setInvalidDecl(); 2828 } 2829 } 2830 } 2831 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2832 Decls.data(), Decls.size())); 2833} 2834 2835 2836/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2837/// to introduce parameters into function prototype scope. 2838Sema::DeclPtrTy 2839Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2840 const DeclSpec &DS = D.getDeclSpec(); 2841 2842 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2843 VarDecl::StorageClass StorageClass = VarDecl::None; 2844 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2845 StorageClass = VarDecl::Register; 2846 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2847 Diag(DS.getStorageClassSpecLoc(), 2848 diag::err_invalid_storage_class_in_func_decl); 2849 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2850 } 2851 2852 if (D.getDeclSpec().isThreadSpecified()) 2853 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2854 2855 DiagnoseFunctionSpecifiers(D); 2856 2857 // Check that there are no default arguments inside the type of this 2858 // parameter (C++ only). 2859 if (getLangOptions().CPlusPlus) 2860 CheckExtraCXXDefaultArguments(D); 2861 2862 TagDecl *OwnedDecl = 0; 2863 QualType parmDeclType = GetTypeForDeclarator(D, S, /*Skip=*/0, &OwnedDecl); 2864 2865 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 2866 // C++ [dcl.fct]p6: 2867 // Types shall not be defined in return or parameter types. 2868 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 2869 << Context.getTypeDeclType(OwnedDecl); 2870 } 2871 2872 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2873 // Can this happen for params? We already checked that they don't conflict 2874 // among each other. Here they can only shadow globals, which is ok. 2875 IdentifierInfo *II = D.getIdentifier(); 2876 if (II) { 2877 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2878 if (PrevDecl->isTemplateParameter()) { 2879 // Maybe we will complain about the shadowed template parameter. 2880 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2881 // Just pretend that we didn't see the previous declaration. 2882 PrevDecl = 0; 2883 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2884 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2885 2886 // Recover by removing the name 2887 II = 0; 2888 D.SetIdentifier(0, D.getIdentifierLoc()); 2889 } 2890 } 2891 } 2892 2893 // Parameters can not be abstract class types. 2894 // For record types, this is done by the AbstractClassUsageDiagnoser once 2895 // the class has been completely parsed. 2896 if (!CurContext->isRecord() && 2897 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2898 diag::err_abstract_type_in_decl, 2899 AbstractParamType)) 2900 D.setInvalidType(true); 2901 2902 QualType T = adjustParameterType(parmDeclType); 2903 2904 ParmVarDecl *New; 2905 if (T == parmDeclType) // parameter type did not need adjustment 2906 New = ParmVarDecl::Create(Context, CurContext, 2907 D.getIdentifierLoc(), II, 2908 parmDeclType, StorageClass, 2909 0); 2910 else // keep track of both the adjusted and unadjusted types 2911 New = OriginalParmVarDecl::Create(Context, CurContext, 2912 D.getIdentifierLoc(), II, T, 2913 parmDeclType, StorageClass, 0); 2914 2915 if (D.isInvalidType()) 2916 New->setInvalidDecl(); 2917 2918 // Parameter declarators cannot be interface types. All ObjC objects are 2919 // passed by reference. 2920 if (T->isObjCInterfaceType()) { 2921 Diag(D.getIdentifierLoc(), 2922 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2923 New->setInvalidDecl(); 2924 } 2925 2926 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2927 if (D.getCXXScopeSpec().isSet()) { 2928 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2929 << D.getCXXScopeSpec().getRange(); 2930 New->setInvalidDecl(); 2931 } 2932 2933 // Add the parameter declaration into this scope. 2934 S->AddDecl(DeclPtrTy::make(New)); 2935 if (II) 2936 IdResolver.AddDecl(New); 2937 2938 ProcessDeclAttributes(S, New, D); 2939 2940 if (New->hasAttr<BlocksAttr>(Context)) { 2941 Diag(New->getLocation(), diag::err_block_on_nonlocal); 2942 } 2943 return DeclPtrTy::make(New); 2944} 2945 2946void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2947 SourceLocation LocAfterDecls) { 2948 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2949 "Not a function declarator!"); 2950 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2951 2952 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2953 // for a K&R function. 2954 if (!FTI.hasPrototype) { 2955 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2956 --i; 2957 if (FTI.ArgInfo[i].Param == 0) { 2958 std::string Code = " int "; 2959 Code += FTI.ArgInfo[i].Ident->getName(); 2960 Code += ";\n"; 2961 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2962 << FTI.ArgInfo[i].Ident 2963 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2964 2965 // Implicitly declare the argument as type 'int' for lack of a better 2966 // type. 2967 DeclSpec DS; 2968 const char* PrevSpec; // unused 2969 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2970 PrevSpec); 2971 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2972 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2973 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2974 } 2975 } 2976 } 2977} 2978 2979Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2980 Declarator &D) { 2981 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2982 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2983 "Not a function declarator!"); 2984 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2985 2986 if (FTI.hasPrototype) { 2987 // FIXME: Diagnose arguments without names in C. 2988 } 2989 2990 Scope *ParentScope = FnBodyScope->getParent(); 2991 2992 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2993 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2994} 2995 2996Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2997 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2998 2999 CurFunctionNeedsScopeChecking = false; 3000 3001 // See if this is a redefinition. 3002 const FunctionDecl *Definition; 3003 if (FD->getBody(Context, Definition)) { 3004 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3005 Diag(Definition->getLocation(), diag::note_previous_definition); 3006 } 3007 3008 // Builtin functions cannot be defined. 3009 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3010 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3011 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3012 FD->setInvalidDecl(); 3013 } 3014 } 3015 3016 // The return type of a function definition must be complete 3017 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3018 QualType ResultType = FD->getResultType(); 3019 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3020 !FD->isInvalidDecl() && 3021 RequireCompleteType(FD->getLocation(), ResultType, 3022 diag::err_func_def_incomplete_result)) 3023 FD->setInvalidDecl(); 3024 3025 // GNU warning -Wmissing-prototypes: 3026 // Warn if a global function is defined without a previous 3027 // prototype declaration. This warning is issued even if the 3028 // definition itself provides a prototype. The aim is to detect 3029 // global functions that fail to be declared in header files. 3030 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3031 !FD->isMain()) { 3032 bool MissingPrototype = true; 3033 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3034 Prev; Prev = Prev->getPreviousDeclaration()) { 3035 // Ignore any declarations that occur in function or method 3036 // scope, because they aren't visible from the header. 3037 if (Prev->getDeclContext()->isFunctionOrMethod()) 3038 continue; 3039 3040 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3041 break; 3042 } 3043 3044 if (MissingPrototype) 3045 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3046 } 3047 3048 if (FnBodyScope) 3049 PushDeclContext(FnBodyScope, FD); 3050 3051 // Check the validity of our function parameters 3052 CheckParmsForFunctionDef(FD); 3053 3054 // Introduce our parameters into the function scope 3055 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3056 ParmVarDecl *Param = FD->getParamDecl(p); 3057 Param->setOwningFunction(FD); 3058 3059 // If this has an identifier, add it to the scope stack. 3060 if (Param->getIdentifier() && FnBodyScope) 3061 PushOnScopeChains(Param, FnBodyScope); 3062 } 3063 3064 // Checking attributes of current function definition 3065 // dllimport attribute. 3066 if (FD->getAttr<DLLImportAttr>(Context) && 3067 (!FD->getAttr<DLLExportAttr>(Context))) { 3068 // dllimport attribute cannot be applied to definition. 3069 if (!(FD->getAttr<DLLImportAttr>(Context))->isInherited()) { 3070 Diag(FD->getLocation(), 3071 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3072 << "dllimport"; 3073 FD->setInvalidDecl(); 3074 return DeclPtrTy::make(FD); 3075 } else { 3076 // If a symbol previously declared dllimport is later defined, the 3077 // attribute is ignored in subsequent references, and a warning is 3078 // emitted. 3079 Diag(FD->getLocation(), 3080 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3081 << FD->getNameAsCString() << "dllimport"; 3082 } 3083 } 3084 return DeclPtrTy::make(FD); 3085} 3086 3087Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3088 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3089} 3090 3091Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3092 bool IsInstantiation) { 3093 Decl *dcl = D.getAs<Decl>(); 3094 Stmt *Body = BodyArg.takeAs<Stmt>(); 3095 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3096 FD->setBody(Body); 3097 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3098 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3099 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3100 MD->setBody(Body); 3101 } else { 3102 Body->Destroy(Context); 3103 return DeclPtrTy(); 3104 } 3105 if (!IsInstantiation) 3106 PopDeclContext(); 3107 3108 // Verify and clean out per-function state. 3109 3110 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3111 3112 // Check goto/label use. 3113 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3114 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3115 LabelStmt *L = I->second; 3116 3117 // Verify that we have no forward references left. If so, there was a goto 3118 // or address of a label taken, but no definition of it. Label fwd 3119 // definitions are indicated with a null substmt. 3120 if (L->getSubStmt() != 0) 3121 continue; 3122 3123 // Emit error. 3124 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3125 3126 // At this point, we have gotos that use the bogus label. Stitch it into 3127 // the function body so that they aren't leaked and that the AST is well 3128 // formed. 3129 if (Body == 0) { 3130 // The whole function wasn't parsed correctly, just delete this. 3131 L->Destroy(Context); 3132 continue; 3133 } 3134 3135 // Otherwise, the body is valid: we want to stitch the label decl into the 3136 // function somewhere so that it is properly owned and so that the goto 3137 // has a valid target. Do this by creating a new compound stmt with the 3138 // label in it. 3139 3140 // Give the label a sub-statement. 3141 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3142 3143 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3144 cast<CXXTryStmt>(Body)->getTryBlock() : 3145 cast<CompoundStmt>(Body); 3146 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3147 Elements.push_back(L); 3148 Compound->setStmts(Context, &Elements[0], Elements.size()); 3149 } 3150 FunctionLabelMap.clear(); 3151 3152 if (!Body) return D; 3153 3154 // Verify that that gotos and switch cases don't jump into scopes illegally. 3155 if (CurFunctionNeedsScopeChecking) 3156 DiagnoseInvalidJumps(Body); 3157 3158 // C++ constructors that have function-try-blocks can't have return statements 3159 // in the handlers of that block. (C++ [except.handle]p14) Verify this. 3160 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3161 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3162 3163 return D; 3164} 3165 3166/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3167/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3168NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3169 IdentifierInfo &II, Scope *S) { 3170 // Before we produce a declaration for an implicitly defined 3171 // function, see whether there was a locally-scoped declaration of 3172 // this name as a function or variable. If so, use that 3173 // (non-visible) declaration, and complain about it. 3174 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3175 = LocallyScopedExternalDecls.find(&II); 3176 if (Pos != LocallyScopedExternalDecls.end()) { 3177 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3178 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3179 return Pos->second; 3180 } 3181 3182 // Extension in C99. Legal in C90, but warn about it. 3183 if (getLangOptions().C99) 3184 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3185 else 3186 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3187 3188 // FIXME: handle stuff like: 3189 // void foo() { extern float X(); } 3190 // void bar() { X(); } <-- implicit decl for X in another scope. 3191 3192 // Set a Declarator for the implicit definition: int foo(); 3193 const char *Dummy; 3194 DeclSpec DS; 3195 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3196 Error = Error; // Silence warning. 3197 assert(!Error && "Error setting up implicit decl!"); 3198 Declarator D(DS, Declarator::BlockContext); 3199 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3200 0, 0, false, SourceLocation(), 3201 false, 0,0,0, Loc, D), 3202 SourceLocation()); 3203 D.SetIdentifier(&II, Loc); 3204 3205 // Insert this function into translation-unit scope. 3206 3207 DeclContext *PrevDC = CurContext; 3208 CurContext = Context.getTranslationUnitDecl(); 3209 3210 FunctionDecl *FD = 3211 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3212 FD->setImplicit(); 3213 3214 CurContext = PrevDC; 3215 3216 AddKnownFunctionAttributes(FD); 3217 3218 return FD; 3219} 3220 3221/// \brief Adds any function attributes that we know a priori based on 3222/// the declaration of this function. 3223/// 3224/// These attributes can apply both to implicitly-declared builtins 3225/// (like __builtin___printf_chk) or to library-declared functions 3226/// like NSLog or printf. 3227void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3228 if (FD->isInvalidDecl()) 3229 return; 3230 3231 // If this is a built-in function, map its builtin attributes to 3232 // actual attributes. 3233 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3234 // Handle printf-formatting attributes. 3235 unsigned FormatIdx; 3236 bool HasVAListArg; 3237 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3238 if (!FD->getAttr<FormatAttr>(Context)) 3239 FD->addAttr(Context, 3240 ::new (Context) FormatAttr("printf", FormatIdx + 1, 3241 HasVAListArg ? 0 : FormatIdx + 2)); 3242 } 3243 3244 // Mark const if we don't care about errno and that is the only 3245 // thing preventing the function from being const. This allows 3246 // IRgen to use LLVM intrinsics for such functions. 3247 if (!getLangOptions().MathErrno && 3248 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3249 if (!FD->getAttr<ConstAttr>(Context)) 3250 FD->addAttr(Context, ::new (Context) ConstAttr()); 3251 } 3252 } 3253 3254 IdentifierInfo *Name = FD->getIdentifier(); 3255 if (!Name) 3256 return; 3257 if ((!getLangOptions().CPlusPlus && 3258 FD->getDeclContext()->isTranslationUnit()) || 3259 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3260 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3261 LinkageSpecDecl::lang_c)) { 3262 // Okay: this could be a libc/libm/Objective-C function we know 3263 // about. 3264 } else 3265 return; 3266 3267 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3268 if (const FormatAttr *Format = FD->getAttr<FormatAttr>(Context)) { 3269 // FIXME: We known better than our headers. 3270 const_cast<FormatAttr *>(Format)->setType("printf"); 3271 } else 3272 FD->addAttr(Context, 3273 ::new (Context) FormatAttr("printf", 1, 3274 Name->isStr("NSLogv") ? 0 : 2)); 3275 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3276 if (!FD->getAttr<FormatAttr>(Context)) 3277 FD->addAttr(Context, 3278 ::new (Context) FormatAttr("printf", 2, 3279 Name->isStr("vasprintf") ? 0 : 3)); 3280 } 3281} 3282 3283TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3284 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3285 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3286 3287 // Scope manipulation handled by caller. 3288 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3289 D.getIdentifierLoc(), 3290 D.getIdentifier(), 3291 T); 3292 3293 if (TagType *TT = dyn_cast<TagType>(T)) { 3294 TagDecl *TD = TT->getDecl(); 3295 3296 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3297 // keep track of the TypedefDecl. 3298 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3299 TD->setTypedefForAnonDecl(NewTD); 3300 } 3301 3302 if (D.isInvalidType()) 3303 NewTD->setInvalidDecl(); 3304 return NewTD; 3305} 3306 3307 3308/// \brief Determine whether a tag with a given kind is acceptable 3309/// as a redeclaration of the given tag declaration. 3310/// 3311/// \returns true if the new tag kind is acceptable, false otherwise. 3312bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 3313 TagDecl::TagKind NewTag, 3314 SourceLocation NewTagLoc, 3315 const IdentifierInfo &Name) { 3316 // C++ [dcl.type.elab]p3: 3317 // The class-key or enum keyword present in the 3318 // elaborated-type-specifier shall agree in kind with the 3319 // declaration to which the name in theelaborated-type-specifier 3320 // refers. This rule also applies to the form of 3321 // elaborated-type-specifier that declares a class-name or 3322 // friend class since it can be construed as referring to the 3323 // definition of the class. Thus, in any 3324 // elaborated-type-specifier, the enum keyword shall be used to 3325 // refer to an enumeration (7.2), the union class-keyshall be 3326 // used to refer to a union (clause 9), and either the class or 3327 // struct class-key shall be used to refer to a class (clause 9) 3328 // declared using the class or struct class-key. 3329 TagDecl::TagKind OldTag = Previous->getTagKind(); 3330 if (OldTag == NewTag) 3331 return true; 3332 3333 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 3334 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 3335 // Warn about the struct/class tag mismatch. 3336 bool isTemplate = false; 3337 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 3338 isTemplate = Record->getDescribedClassTemplate(); 3339 3340 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 3341 << (NewTag == TagDecl::TK_class) 3342 << isTemplate << &Name 3343 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 3344 OldTag == TagDecl::TK_class? "class" : "struct"); 3345 Diag(Previous->getLocation(), diag::note_previous_use); 3346 return true; 3347 } 3348 return false; 3349} 3350 3351/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3352/// former case, Name will be non-null. In the later case, Name will be null. 3353/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3354/// reference/declaration/definition of a tag. 3355Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3356 SourceLocation KWLoc, const CXXScopeSpec &SS, 3357 IdentifierInfo *Name, SourceLocation NameLoc, 3358 AttributeList *Attr, AccessSpecifier AS, 3359 bool &OwnedDecl) { 3360 // If this is not a definition, it must have a name. 3361 assert((Name != 0 || TK == TK_Definition) && 3362 "Nameless record must be a definition!"); 3363 3364 OwnedDecl = false; 3365 TagDecl::TagKind Kind; 3366 switch (TagSpec) { 3367 default: assert(0 && "Unknown tag type!"); 3368 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3369 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3370 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3371 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3372 } 3373 3374 DeclContext *SearchDC = CurContext; 3375 DeclContext *DC = CurContext; 3376 NamedDecl *PrevDecl = 0; 3377 3378 bool Invalid = false; 3379 3380 if (Name && SS.isNotEmpty()) { 3381 // We have a nested-name tag ('struct foo::bar'). 3382 3383 // Check for invalid 'foo::'. 3384 if (SS.isInvalid()) { 3385 Name = 0; 3386 goto CreateNewDecl; 3387 } 3388 3389 if (RequireCompleteDeclContext(SS)) 3390 return DeclPtrTy::make((Decl *)0); 3391 3392 DC = computeDeclContext(SS); 3393 SearchDC = DC; 3394 // Look-up name inside 'foo::'. 3395 PrevDecl 3396 = dyn_cast_or_null<TagDecl>( 3397 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3398 3399 // A tag 'foo::bar' must already exist. 3400 if (PrevDecl == 0) { 3401 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3402 Name = 0; 3403 Invalid = true; 3404 goto CreateNewDecl; 3405 } 3406 } else if (Name) { 3407 // If this is a named struct, check to see if there was a previous forward 3408 // declaration or definition. 3409 // FIXME: We're looking into outer scopes here, even when we 3410 // shouldn't be. Doing so can result in ambiguities that we 3411 // shouldn't be diagnosing. 3412 LookupResult R = LookupName(S, Name, LookupTagName, 3413 /*RedeclarationOnly=*/(TK != TK_Reference)); 3414 if (R.isAmbiguous()) { 3415 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3416 // FIXME: This is not best way to recover from case like: 3417 // 3418 // struct S s; 3419 // 3420 // causes needless "incomplete type" error later. 3421 Name = 0; 3422 PrevDecl = 0; 3423 Invalid = true; 3424 } 3425 else 3426 PrevDecl = R; 3427 3428 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3429 // FIXME: This makes sure that we ignore the contexts associated 3430 // with C structs, unions, and enums when looking for a matching 3431 // tag declaration or definition. See the similar lookup tweak 3432 // in Sema::LookupName; is there a better way to deal with this? 3433 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3434 SearchDC = SearchDC->getParent(); 3435 } 3436 } 3437 3438 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3439 // Maybe we will complain about the shadowed template parameter. 3440 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3441 // Just pretend that we didn't see the previous declaration. 3442 PrevDecl = 0; 3443 } 3444 3445 if (PrevDecl) { 3446 // Check whether the previous declaration is usable. 3447 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3448 3449 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3450 // If this is a use of a previous tag, or if the tag is already declared 3451 // in the same scope (so that the definition/declaration completes or 3452 // rementions the tag), reuse the decl. 3453 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3454 // Make sure that this wasn't declared as an enum and now used as a 3455 // struct or something similar. 3456 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 3457 bool SafeToContinue 3458 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3459 Kind != TagDecl::TK_enum); 3460 if (SafeToContinue) 3461 Diag(KWLoc, diag::err_use_with_wrong_tag) 3462 << Name 3463 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3464 PrevTagDecl->getKindName()); 3465 else 3466 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3467 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3468 3469 if (SafeToContinue) 3470 Kind = PrevTagDecl->getTagKind(); 3471 else { 3472 // Recover by making this an anonymous redefinition. 3473 Name = 0; 3474 PrevDecl = 0; 3475 Invalid = true; 3476 } 3477 } 3478 3479 if (!Invalid) { 3480 // If this is a use, just return the declaration we found. 3481 3482 // FIXME: In the future, return a variant or some other clue 3483 // for the consumer of this Decl to know it doesn't own it. 3484 // For our current ASTs this shouldn't be a problem, but will 3485 // need to be changed with DeclGroups. 3486 if (TK == TK_Reference) 3487 return DeclPtrTy::make(PrevDecl); 3488 3489 // Diagnose attempts to redefine a tag. 3490 if (TK == TK_Definition) { 3491 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3492 Diag(NameLoc, diag::err_redefinition) << Name; 3493 Diag(Def->getLocation(), diag::note_previous_definition); 3494 // If this is a redefinition, recover by making this 3495 // struct be anonymous, which will make any later 3496 // references get the previous definition. 3497 Name = 0; 3498 PrevDecl = 0; 3499 Invalid = true; 3500 } else { 3501 // If the type is currently being defined, complain 3502 // about a nested redefinition. 3503 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3504 if (Tag->isBeingDefined()) { 3505 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3506 Diag(PrevTagDecl->getLocation(), 3507 diag::note_previous_definition); 3508 Name = 0; 3509 PrevDecl = 0; 3510 Invalid = true; 3511 } 3512 } 3513 3514 // Okay, this is definition of a previously declared or referenced 3515 // tag PrevDecl. We're going to create a new Decl for it. 3516 } 3517 } 3518 // If we get here we have (another) forward declaration or we 3519 // have a definition. Just create a new decl. 3520 } else { 3521 // If we get here, this is a definition of a new tag type in a nested 3522 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3523 // new decl/type. We set PrevDecl to NULL so that the entities 3524 // have distinct types. 3525 PrevDecl = 0; 3526 } 3527 // If we get here, we're going to create a new Decl. If PrevDecl 3528 // is non-NULL, it's a definition of the tag declared by 3529 // PrevDecl. If it's NULL, we have a new definition. 3530 } else { 3531 // PrevDecl is a namespace, template, or anything else 3532 // that lives in the IDNS_Tag identifier namespace. 3533 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3534 // The tag name clashes with a namespace name, issue an error and 3535 // recover by making this tag be anonymous. 3536 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3537 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3538 Name = 0; 3539 PrevDecl = 0; 3540 Invalid = true; 3541 } else { 3542 // The existing declaration isn't relevant to us; we're in a 3543 // new scope, so clear out the previous declaration. 3544 PrevDecl = 0; 3545 } 3546 } 3547 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3548 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3549 // C++ [basic.scope.pdecl]p5: 3550 // -- for an elaborated-type-specifier of the form 3551 // 3552 // class-key identifier 3553 // 3554 // if the elaborated-type-specifier is used in the 3555 // decl-specifier-seq or parameter-declaration-clause of a 3556 // function defined in namespace scope, the identifier is 3557 // declared as a class-name in the namespace that contains 3558 // the declaration; otherwise, except as a friend 3559 // declaration, the identifier is declared in the smallest 3560 // non-class, non-function-prototype scope that contains the 3561 // declaration. 3562 // 3563 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3564 // C structs and unions. 3565 // 3566 // GNU C also supports this behavior as part of its incomplete 3567 // enum types extension, while GNU C++ does not. 3568 // 3569 // Find the context where we'll be declaring the tag. 3570 // FIXME: We would like to maintain the current DeclContext as the 3571 // lexical context, 3572 while (SearchDC->isRecord()) 3573 SearchDC = SearchDC->getParent(); 3574 3575 // Find the scope where we'll be declaring the tag. 3576 while (S->isClassScope() || 3577 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3578 ((S->getFlags() & Scope::DeclScope) == 0) || 3579 (S->getEntity() && 3580 ((DeclContext *)S->getEntity())->isTransparentContext())) 3581 S = S->getParent(); 3582 } 3583 3584CreateNewDecl: 3585 3586 // If there is an identifier, use the location of the identifier as the 3587 // location of the decl, otherwise use the location of the struct/union 3588 // keyword. 3589 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3590 3591 // Otherwise, create a new declaration. If there is a previous 3592 // declaration of the same entity, the two will be linked via 3593 // PrevDecl. 3594 TagDecl *New; 3595 3596 if (Kind == TagDecl::TK_enum) { 3597 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3598 // enum X { A, B, C } D; D should chain to X. 3599 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3600 cast_or_null<EnumDecl>(PrevDecl)); 3601 // If this is an undefined enum, warn. 3602 if (TK != TK_Definition && !Invalid) { 3603 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3604 : diag::ext_forward_ref_enum; 3605 Diag(Loc, DK); 3606 } 3607 } else { 3608 // struct/union/class 3609 3610 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3611 // struct X { int A; } D; D should chain to X. 3612 if (getLangOptions().CPlusPlus) 3613 // FIXME: Look for a way to use RecordDecl for simple structs. 3614 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3615 cast_or_null<CXXRecordDecl>(PrevDecl)); 3616 else 3617 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3618 cast_or_null<RecordDecl>(PrevDecl)); 3619 } 3620 3621 if (Kind != TagDecl::TK_enum) { 3622 // Handle #pragma pack: if the #pragma pack stack has non-default 3623 // alignment, make up a packed attribute for this decl. These 3624 // attributes are checked when the ASTContext lays out the 3625 // structure. 3626 // 3627 // It is important for implementing the correct semantics that this 3628 // happen here (in act on tag decl). The #pragma pack stack is 3629 // maintained as a result of parser callbacks which can occur at 3630 // many points during the parsing of a struct declaration (because 3631 // the #pragma tokens are effectively skipped over during the 3632 // parsing of the struct). 3633 if (unsigned Alignment = getPragmaPackAlignment()) 3634 New->addAttr(Context, ::new (Context) PackedAttr(Alignment * 8)); 3635 } 3636 3637 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3638 // C++ [dcl.typedef]p3: 3639 // [...] Similarly, in a given scope, a class or enumeration 3640 // shall not be declared with the same name as a typedef-name 3641 // that is declared in that scope and refers to a type other 3642 // than the class or enumeration itself. 3643 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3644 TypedefDecl *PrevTypedef = 0; 3645 if (Lookup.getKind() == LookupResult::Found) 3646 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3647 3648 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3649 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3650 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3651 Diag(Loc, diag::err_tag_definition_of_typedef) 3652 << Context.getTypeDeclType(New) 3653 << PrevTypedef->getUnderlyingType(); 3654 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3655 Invalid = true; 3656 } 3657 } 3658 3659 if (Invalid) 3660 New->setInvalidDecl(); 3661 3662 if (Attr) 3663 ProcessDeclAttributeList(S, New, Attr); 3664 3665 // If we're declaring or defining a tag in function prototype scope 3666 // in C, note that this type can only be used within the function. 3667 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3668 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3669 3670 // Set the lexical context. If the tag has a C++ scope specifier, the 3671 // lexical context will be different from the semantic context. 3672 New->setLexicalDeclContext(CurContext); 3673 3674 // Set the access specifier. 3675 if (!Invalid) 3676 SetMemberAccessSpecifier(New, PrevDecl, AS); 3677 3678 if (TK == TK_Definition) 3679 New->startDefinition(); 3680 3681 // If this has an identifier, add it to the scope stack. 3682 if (Name) { 3683 S = getNonFieldDeclScope(S); 3684 PushOnScopeChains(New, S); 3685 } else { 3686 CurContext->addDecl(Context, New); 3687 } 3688 3689 OwnedDecl = true; 3690 return DeclPtrTy::make(New); 3691} 3692 3693void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3694 AdjustDeclIfTemplate(TagD); 3695 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3696 3697 // Enter the tag context. 3698 PushDeclContext(S, Tag); 3699 3700 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3701 FieldCollector->StartClass(); 3702 3703 if (Record->getIdentifier()) { 3704 // C++ [class]p2: 3705 // [...] The class-name is also inserted into the scope of the 3706 // class itself; this is known as the injected-class-name. For 3707 // purposes of access checking, the injected-class-name is treated 3708 // as if it were a public member name. 3709 CXXRecordDecl *InjectedClassName 3710 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3711 CurContext, Record->getLocation(), 3712 Record->getIdentifier(), Record); 3713 InjectedClassName->setImplicit(); 3714 InjectedClassName->setAccess(AS_public); 3715 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3716 InjectedClassName->setDescribedClassTemplate(Template); 3717 PushOnScopeChains(InjectedClassName, S); 3718 assert(InjectedClassName->isInjectedClassName() && 3719 "Broken injected-class-name"); 3720 } 3721 } 3722} 3723 3724void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3725 AdjustDeclIfTemplate(TagD); 3726 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3727 3728 if (isa<CXXRecordDecl>(Tag)) 3729 FieldCollector->FinishClass(); 3730 3731 // Exit this scope of this tag's definition. 3732 PopDeclContext(); 3733 3734 // Notify the consumer that we've defined a tag. 3735 Consumer.HandleTagDeclDefinition(Tag); 3736} 3737 3738// Note that FieldName may be null for anonymous bitfields. 3739bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3740 QualType FieldTy, const Expr *BitWidth) { 3741 3742 // C99 6.7.2.1p4 - verify the field type. 3743 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3744 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3745 // Handle incomplete types with specific error. 3746 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3747 return true; 3748 if (FieldName) 3749 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3750 << FieldName << FieldTy << BitWidth->getSourceRange(); 3751 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3752 << FieldTy << BitWidth->getSourceRange(); 3753 } 3754 3755 // If the bit-width is type- or value-dependent, don't try to check 3756 // it now. 3757 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3758 return false; 3759 3760 llvm::APSInt Value; 3761 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3762 return true; 3763 3764 // Zero-width bitfield is ok for anonymous field. 3765 if (Value == 0 && FieldName) 3766 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3767 3768 if (Value.isSigned() && Value.isNegative()) { 3769 if (FieldName) 3770 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3771 << FieldName << Value.toString(10); 3772 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3773 << Value.toString(10); 3774 } 3775 3776 if (!FieldTy->isDependentType()) { 3777 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3778 if (Value.getZExtValue() > TypeSize) { 3779 if (FieldName) 3780 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3781 << FieldName << (unsigned)TypeSize; 3782 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3783 << (unsigned)TypeSize; 3784 } 3785 } 3786 3787 return false; 3788} 3789 3790/// ActOnField - Each field of a struct/union/class is passed into this in order 3791/// to create a FieldDecl object for it. 3792Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3793 SourceLocation DeclStart, 3794 Declarator &D, ExprTy *BitfieldWidth) { 3795 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3796 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3797 AS_public); 3798 return DeclPtrTy::make(Res); 3799} 3800 3801/// HandleField - Analyze a field of a C struct or a C++ data member. 3802/// 3803FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3804 SourceLocation DeclStart, 3805 Declarator &D, Expr *BitWidth, 3806 AccessSpecifier AS) { 3807 IdentifierInfo *II = D.getIdentifier(); 3808 SourceLocation Loc = DeclStart; 3809 if (II) Loc = D.getIdentifierLoc(); 3810 3811 QualType T = GetTypeForDeclarator(D, S); 3812 if (getLangOptions().CPlusPlus) 3813 CheckExtraCXXDefaultArguments(D); 3814 3815 DiagnoseFunctionSpecifiers(D); 3816 3817 if (D.getDeclSpec().isThreadSpecified()) 3818 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3819 3820 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3821 3822 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3823 // Maybe we will complain about the shadowed template parameter. 3824 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3825 // Just pretend that we didn't see the previous declaration. 3826 PrevDecl = 0; 3827 } 3828 3829 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3830 PrevDecl = 0; 3831 3832 FieldDecl *NewFD 3833 = CheckFieldDecl(II, T, Record, Loc, 3834 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3835 BitWidth, AS, PrevDecl, &D); 3836 if (NewFD->isInvalidDecl() && PrevDecl) { 3837 // Don't introduce NewFD into scope; there's already something 3838 // with the same name in the same scope. 3839 } else if (II) { 3840 PushOnScopeChains(NewFD, S); 3841 } else 3842 Record->addDecl(Context, NewFD); 3843 3844 return NewFD; 3845} 3846 3847/// \brief Build a new FieldDecl and check its well-formedness. 3848/// 3849/// This routine builds a new FieldDecl given the fields name, type, 3850/// record, etc. \p PrevDecl should refer to any previous declaration 3851/// with the same name and in the same scope as the field to be 3852/// created. 3853/// 3854/// \returns a new FieldDecl. 3855/// 3856/// \todo The Declarator argument is a hack. It will be removed once 3857FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3858 RecordDecl *Record, SourceLocation Loc, 3859 bool Mutable, Expr *BitWidth, 3860 AccessSpecifier AS, NamedDecl *PrevDecl, 3861 Declarator *D) { 3862 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3863 bool InvalidDecl = false; 3864 if (D) InvalidDecl = D->isInvalidType(); 3865 3866 // If we receive a broken type, recover by assuming 'int' and 3867 // marking this declaration as invalid. 3868 if (T.isNull()) { 3869 InvalidDecl = true; 3870 T = Context.IntTy; 3871 } 3872 3873 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3874 // than a variably modified type. 3875 if (T->isVariablyModifiedType()) { 3876 bool SizeIsNegative; 3877 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3878 SizeIsNegative); 3879 if (!FixedTy.isNull()) { 3880 Diag(Loc, diag::warn_illegal_constant_array_size); 3881 T = FixedTy; 3882 } else { 3883 if (SizeIsNegative) 3884 Diag(Loc, diag::err_typecheck_negative_array_size); 3885 else 3886 Diag(Loc, diag::err_typecheck_field_variable_size); 3887 T = Context.IntTy; 3888 InvalidDecl = true; 3889 } 3890 } 3891 3892 // Fields can not have abstract class types 3893 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3894 AbstractFieldType)) 3895 InvalidDecl = true; 3896 3897 // If this is declared as a bit-field, check the bit-field. 3898 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3899 InvalidDecl = true; 3900 DeleteExpr(BitWidth); 3901 BitWidth = 0; 3902 } 3903 3904 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3905 Mutable); 3906 if (InvalidDecl) 3907 NewFD->setInvalidDecl(); 3908 3909 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3910 Diag(Loc, diag::err_duplicate_member) << II; 3911 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3912 NewFD->setInvalidDecl(); 3913 } 3914 3915 if (getLangOptions().CPlusPlus && !T->isPODType()) 3916 cast<CXXRecordDecl>(Record)->setPOD(false); 3917 3918 // FIXME: We need to pass in the attributes given an AST 3919 // representation, not a parser representation. 3920 if (D) 3921 // FIXME: What to pass instead of TUScope? 3922 ProcessDeclAttributes(TUScope, NewFD, *D); 3923 3924 if (T.isObjCGCWeak()) 3925 Diag(Loc, diag::warn_attribute_weak_on_field); 3926 3927 NewFD->setAccess(AS); 3928 3929 // C++ [dcl.init.aggr]p1: 3930 // An aggregate is an array or a class (clause 9) with [...] no 3931 // private or protected non-static data members (clause 11). 3932 // A POD must be an aggregate. 3933 if (getLangOptions().CPlusPlus && 3934 (AS == AS_private || AS == AS_protected)) { 3935 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3936 CXXRecord->setAggregate(false); 3937 CXXRecord->setPOD(false); 3938 } 3939 3940 return NewFD; 3941} 3942 3943/// TranslateIvarVisibility - Translate visibility from a token ID to an 3944/// AST enum value. 3945static ObjCIvarDecl::AccessControl 3946TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3947 switch (ivarVisibility) { 3948 default: assert(0 && "Unknown visitibility kind"); 3949 case tok::objc_private: return ObjCIvarDecl::Private; 3950 case tok::objc_public: return ObjCIvarDecl::Public; 3951 case tok::objc_protected: return ObjCIvarDecl::Protected; 3952 case tok::objc_package: return ObjCIvarDecl::Package; 3953 } 3954} 3955 3956/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3957/// in order to create an IvarDecl object for it. 3958Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3959 SourceLocation DeclStart, 3960 DeclPtrTy IntfDecl, 3961 Declarator &D, ExprTy *BitfieldWidth, 3962 tok::ObjCKeywordKind Visibility) { 3963 3964 IdentifierInfo *II = D.getIdentifier(); 3965 Expr *BitWidth = (Expr*)BitfieldWidth; 3966 SourceLocation Loc = DeclStart; 3967 if (II) Loc = D.getIdentifierLoc(); 3968 3969 // FIXME: Unnamed fields can be handled in various different ways, for 3970 // example, unnamed unions inject all members into the struct namespace! 3971 3972 QualType T = GetTypeForDeclarator(D, S); 3973 3974 if (BitWidth) { 3975 // 6.7.2.1p3, 6.7.2.1p4 3976 if (VerifyBitField(Loc, II, T, BitWidth)) { 3977 D.setInvalidType(); 3978 DeleteExpr(BitWidth); 3979 BitWidth = 0; 3980 } 3981 } else { 3982 // Not a bitfield. 3983 3984 // validate II. 3985 3986 } 3987 3988 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3989 // than a variably modified type. 3990 if (T->isVariablyModifiedType()) { 3991 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3992 D.setInvalidType(); 3993 } 3994 3995 // Get the visibility (access control) for this ivar. 3996 ObjCIvarDecl::AccessControl ac = 3997 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3998 : ObjCIvarDecl::None; 3999 // Must set ivar's DeclContext to its enclosing interface. 4000 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 4001 DeclContext *EnclosingContext; 4002 if (ObjCImplementationDecl *IMPDecl = 4003 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4004 // Case of ivar declared in an implementation. Context is that of its class. 4005 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 4006 assert(IDecl && "No class- ActOnIvar"); 4007 EnclosingContext = cast_or_null<DeclContext>(IDecl); 4008 } 4009 else 4010 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 4011 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 4012 4013 // Construct the decl. 4014 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 4015 EnclosingContext, Loc, II, T,ac, 4016 (Expr *)BitfieldWidth); 4017 4018 if (II) { 4019 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 4020 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 4021 && !isa<TagDecl>(PrevDecl)) { 4022 Diag(Loc, diag::err_duplicate_member) << II; 4023 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4024 NewID->setInvalidDecl(); 4025 } 4026 } 4027 4028 // Process attributes attached to the ivar. 4029 ProcessDeclAttributes(S, NewID, D); 4030 4031 if (D.isInvalidType()) 4032 NewID->setInvalidDecl(); 4033 4034 if (II) { 4035 // FIXME: When interfaces are DeclContexts, we'll need to add 4036 // these to the interface. 4037 S->AddDecl(DeclPtrTy::make(NewID)); 4038 IdResolver.AddDecl(NewID); 4039 } 4040 4041 return DeclPtrTy::make(NewID); 4042} 4043 4044void Sema::ActOnFields(Scope* S, 4045 SourceLocation RecLoc, DeclPtrTy RecDecl, 4046 DeclPtrTy *Fields, unsigned NumFields, 4047 SourceLocation LBrac, SourceLocation RBrac, 4048 AttributeList *Attr) { 4049 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 4050 assert(EnclosingDecl && "missing record or interface decl"); 4051 4052 // If the decl this is being inserted into is invalid, then it may be a 4053 // redeclaration or some other bogus case. Don't try to add fields to it. 4054 if (EnclosingDecl->isInvalidDecl()) { 4055 // FIXME: Deallocate fields? 4056 return; 4057 } 4058 4059 4060 // Verify that all the fields are okay. 4061 unsigned NumNamedMembers = 0; 4062 llvm::SmallVector<FieldDecl*, 32> RecFields; 4063 4064 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 4065 for (unsigned i = 0; i != NumFields; ++i) { 4066 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 4067 4068 // Get the type for the field. 4069 Type *FDTy = FD->getType().getTypePtr(); 4070 4071 if (!FD->isAnonymousStructOrUnion()) { 4072 // Remember all fields written by the user. 4073 RecFields.push_back(FD); 4074 } 4075 4076 // If the field is already invalid for some reason, don't emit more 4077 // diagnostics about it. 4078 if (FD->isInvalidDecl()) 4079 continue; 4080 4081 // C99 6.7.2.1p2: 4082 // A structure or union shall not contain a member with 4083 // incomplete or function type (hence, a structure shall not 4084 // contain an instance of itself, but may contain a pointer to 4085 // an instance of itself), except that the last member of a 4086 // structure with more than one named member may have incomplete 4087 // array type; such a structure (and any union containing, 4088 // possibly recursively, a member that is such a structure) 4089 // shall not be a member of a structure or an element of an 4090 // array. 4091 if (FDTy->isFunctionType()) { 4092 // Field declared as a function. 4093 Diag(FD->getLocation(), diag::err_field_declared_as_function) 4094 << FD->getDeclName(); 4095 FD->setInvalidDecl(); 4096 EnclosingDecl->setInvalidDecl(); 4097 continue; 4098 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 4099 Record && Record->isStruct()) { 4100 // Flexible array member. 4101 if (NumNamedMembers < 1) { 4102 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 4103 << FD->getDeclName(); 4104 FD->setInvalidDecl(); 4105 EnclosingDecl->setInvalidDecl(); 4106 continue; 4107 } 4108 // Okay, we have a legal flexible array member at the end of the struct. 4109 if (Record) 4110 Record->setHasFlexibleArrayMember(true); 4111 } else if (!FDTy->isDependentType() && 4112 RequireCompleteType(FD->getLocation(), FD->getType(), 4113 diag::err_field_incomplete)) { 4114 // Incomplete type 4115 FD->setInvalidDecl(); 4116 EnclosingDecl->setInvalidDecl(); 4117 continue; 4118 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 4119 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 4120 // If this is a member of a union, then entire union becomes "flexible". 4121 if (Record && Record->isUnion()) { 4122 Record->setHasFlexibleArrayMember(true); 4123 } else { 4124 // If this is a struct/class and this is not the last element, reject 4125 // it. Note that GCC supports variable sized arrays in the middle of 4126 // structures. 4127 if (i != NumFields-1) 4128 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 4129 << FD->getDeclName() << FD->getType(); 4130 else { 4131 // We support flexible arrays at the end of structs in 4132 // other structs as an extension. 4133 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 4134 << FD->getDeclName(); 4135 if (Record) 4136 Record->setHasFlexibleArrayMember(true); 4137 } 4138 } 4139 } 4140 } else if (FDTy->isObjCInterfaceType()) { 4141 /// A field cannot be an Objective-c object 4142 Diag(FD->getLocation(), diag::err_statically_allocated_object); 4143 FD->setInvalidDecl(); 4144 EnclosingDecl->setInvalidDecl(); 4145 continue; 4146 } 4147 // Keep track of the number of named members. 4148 if (FD->getIdentifier()) 4149 ++NumNamedMembers; 4150 } 4151 4152 // Okay, we successfully defined 'Record'. 4153 if (Record) { 4154 Record->completeDefinition(Context); 4155 } else { 4156 ObjCIvarDecl **ClsFields = 4157 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 4158 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 4159 ID->setIVarList(ClsFields, RecFields.size(), Context); 4160 ID->setLocEnd(RBrac); 4161 // Add ivar's to class's DeclContext. 4162 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 4163 ClsFields[i]->setLexicalDeclContext(ID); 4164 ID->addDecl(Context, ClsFields[i]); 4165 } 4166 // Must enforce the rule that ivars in the base classes may not be 4167 // duplicates. 4168 if (ID->getSuperClass()) { 4169 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4170 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4171 ObjCIvarDecl* Ivar = (*IVI); 4172 4173 if (IdentifierInfo *II = Ivar->getIdentifier()) { 4174 ObjCIvarDecl* prevIvar = 4175 ID->getSuperClass()->lookupInstanceVariable(Context, II); 4176 if (prevIvar) { 4177 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4178 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4179 } 4180 } 4181 } 4182 } 4183 } else if (ObjCImplementationDecl *IMPDecl = 4184 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4185 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4186 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 4187 // Ivar declared in @implementation never belongs to the implementation. 4188 // Only it is in implementation's lexical context. 4189 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4190 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4191 } 4192 } 4193 4194 if (Attr) 4195 ProcessDeclAttributeList(S, Record, Attr); 4196} 4197 4198EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4199 EnumConstantDecl *LastEnumConst, 4200 SourceLocation IdLoc, 4201 IdentifierInfo *Id, 4202 ExprArg val) { 4203 Expr *Val = (Expr *)val.get(); 4204 4205 llvm::APSInt EnumVal(32); 4206 QualType EltTy; 4207 if (Val && !Val->isTypeDependent()) { 4208 // Make sure to promote the operand type to int. 4209 UsualUnaryConversions(Val); 4210 if (Val != val.get()) { 4211 val.release(); 4212 val = Val; 4213 } 4214 4215 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4216 SourceLocation ExpLoc; 4217 if (!Val->isValueDependent() && 4218 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4219 Val = 0; 4220 } else { 4221 EltTy = Val->getType(); 4222 } 4223 } 4224 4225 if (!Val) { 4226 if (LastEnumConst) { 4227 // Assign the last value + 1. 4228 EnumVal = LastEnumConst->getInitVal(); 4229 ++EnumVal; 4230 4231 // Check for overflow on increment. 4232 if (EnumVal < LastEnumConst->getInitVal()) 4233 Diag(IdLoc, diag::warn_enum_value_overflow); 4234 4235 EltTy = LastEnumConst->getType(); 4236 } else { 4237 // First value, set to zero. 4238 EltTy = Context.IntTy; 4239 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4240 } 4241 } 4242 4243 val.release(); 4244 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4245 Val, EnumVal); 4246} 4247 4248 4249Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4250 DeclPtrTy lastEnumConst, 4251 SourceLocation IdLoc, 4252 IdentifierInfo *Id, 4253 SourceLocation EqualLoc, ExprTy *val) { 4254 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4255 EnumConstantDecl *LastEnumConst = 4256 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4257 Expr *Val = static_cast<Expr*>(val); 4258 4259 // The scope passed in may not be a decl scope. Zip up the scope tree until 4260 // we find one that is. 4261 S = getNonFieldDeclScope(S); 4262 4263 // Verify that there isn't already something declared with this name in this 4264 // scope. 4265 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4266 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4267 // Maybe we will complain about the shadowed template parameter. 4268 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4269 // Just pretend that we didn't see the previous declaration. 4270 PrevDecl = 0; 4271 } 4272 4273 if (PrevDecl) { 4274 // When in C++, we may get a TagDecl with the same name; in this case the 4275 // enum constant will 'hide' the tag. 4276 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4277 "Received TagDecl when not in C++!"); 4278 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4279 if (isa<EnumConstantDecl>(PrevDecl)) 4280 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4281 else 4282 Diag(IdLoc, diag::err_redefinition) << Id; 4283 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4284 if (Val) Val->Destroy(Context); 4285 return DeclPtrTy(); 4286 } 4287 } 4288 4289 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4290 IdLoc, Id, Owned(Val)); 4291 4292 // Register this decl in the current scope stack. 4293 if (New) 4294 PushOnScopeChains(New, S); 4295 4296 return DeclPtrTy::make(New); 4297} 4298 4299void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 4300 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 4301 DeclPtrTy *Elements, unsigned NumElements) { 4302 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4303 QualType EnumType = Context.getTypeDeclType(Enum); 4304 4305 // TODO: If the result value doesn't fit in an int, it must be a long or long 4306 // long value. ISO C does not support this, but GCC does as an extension, 4307 // emit a warning. 4308 unsigned IntWidth = Context.Target.getIntWidth(); 4309 4310 // Verify that all the values are okay, compute the size of the values, and 4311 // reverse the list. 4312 unsigned NumNegativeBits = 0; 4313 unsigned NumPositiveBits = 0; 4314 4315 // Keep track of whether all elements have type int. 4316 bool AllElementsInt = true; 4317 4318 for (unsigned i = 0; i != NumElements; ++i) { 4319 EnumConstantDecl *ECD = 4320 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4321 if (!ECD) continue; // Already issued a diagnostic. 4322 4323 // If the enum value doesn't fit in an int, emit an extension warning. 4324 const llvm::APSInt &InitVal = ECD->getInitVal(); 4325 assert(InitVal.getBitWidth() >= IntWidth && 4326 "Should have promoted value to int"); 4327 if (InitVal.getBitWidth() > IntWidth) { 4328 llvm::APSInt V(InitVal); 4329 V.trunc(IntWidth); 4330 V.extend(InitVal.getBitWidth()); 4331 if (V != InitVal) 4332 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4333 << InitVal.toString(10); 4334 } 4335 4336 // Keep track of the size of positive and negative values. 4337 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4338 NumPositiveBits = std::max(NumPositiveBits, 4339 (unsigned)InitVal.getActiveBits()); 4340 else 4341 NumNegativeBits = std::max(NumNegativeBits, 4342 (unsigned)InitVal.getMinSignedBits()); 4343 4344 // Keep track of whether every enum element has type int (very commmon). 4345 if (AllElementsInt) 4346 AllElementsInt = ECD->getType() == Context.IntTy; 4347 } 4348 4349 // Figure out the type that should be used for this enum. 4350 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4351 QualType BestType; 4352 unsigned BestWidth; 4353 4354 if (NumNegativeBits) { 4355 // If there is a negative value, figure out the smallest integer type (of 4356 // int/long/longlong) that fits. 4357 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4358 BestType = Context.IntTy; 4359 BestWidth = IntWidth; 4360 } else { 4361 BestWidth = Context.Target.getLongWidth(); 4362 4363 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4364 BestType = Context.LongTy; 4365 else { 4366 BestWidth = Context.Target.getLongLongWidth(); 4367 4368 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4369 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4370 BestType = Context.LongLongTy; 4371 } 4372 } 4373 } else { 4374 // If there is no negative value, figure out which of uint, ulong, ulonglong 4375 // fits. 4376 if (NumPositiveBits <= IntWidth) { 4377 BestType = Context.UnsignedIntTy; 4378 BestWidth = IntWidth; 4379 } else if (NumPositiveBits <= 4380 (BestWidth = Context.Target.getLongWidth())) { 4381 BestType = Context.UnsignedLongTy; 4382 } else { 4383 BestWidth = Context.Target.getLongLongWidth(); 4384 assert(NumPositiveBits <= BestWidth && 4385 "How could an initializer get larger than ULL?"); 4386 BestType = Context.UnsignedLongLongTy; 4387 } 4388 } 4389 4390 // Loop over all of the enumerator constants, changing their types to match 4391 // the type of the enum if needed. 4392 for (unsigned i = 0; i != NumElements; ++i) { 4393 EnumConstantDecl *ECD = 4394 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4395 if (!ECD) continue; // Already issued a diagnostic. 4396 4397 // Standard C says the enumerators have int type, but we allow, as an 4398 // extension, the enumerators to be larger than int size. If each 4399 // enumerator value fits in an int, type it as an int, otherwise type it the 4400 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4401 // that X has type 'int', not 'unsigned'. 4402 if (ECD->getType() == Context.IntTy) { 4403 // Make sure the init value is signed. 4404 llvm::APSInt IV = ECD->getInitVal(); 4405 IV.setIsSigned(true); 4406 ECD->setInitVal(IV); 4407 4408 if (getLangOptions().CPlusPlus) 4409 // C++ [dcl.enum]p4: Following the closing brace of an 4410 // enum-specifier, each enumerator has the type of its 4411 // enumeration. 4412 ECD->setType(EnumType); 4413 continue; // Already int type. 4414 } 4415 4416 // Determine whether the value fits into an int. 4417 llvm::APSInt InitVal = ECD->getInitVal(); 4418 bool FitsInInt; 4419 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4420 FitsInInt = InitVal.getActiveBits() < IntWidth; 4421 else 4422 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4423 4424 // If it fits into an integer type, force it. Otherwise force it to match 4425 // the enum decl type. 4426 QualType NewTy; 4427 unsigned NewWidth; 4428 bool NewSign; 4429 if (FitsInInt) { 4430 NewTy = Context.IntTy; 4431 NewWidth = IntWidth; 4432 NewSign = true; 4433 } else if (ECD->getType() == BestType) { 4434 // Already the right type! 4435 if (getLangOptions().CPlusPlus) 4436 // C++ [dcl.enum]p4: Following the closing brace of an 4437 // enum-specifier, each enumerator has the type of its 4438 // enumeration. 4439 ECD->setType(EnumType); 4440 continue; 4441 } else { 4442 NewTy = BestType; 4443 NewWidth = BestWidth; 4444 NewSign = BestType->isSignedIntegerType(); 4445 } 4446 4447 // Adjust the APSInt value. 4448 InitVal.extOrTrunc(NewWidth); 4449 InitVal.setIsSigned(NewSign); 4450 ECD->setInitVal(InitVal); 4451 4452 // Adjust the Expr initializer and type. 4453 if (ECD->getInitExpr()) 4454 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4455 /*isLvalue=*/false)); 4456 if (getLangOptions().CPlusPlus) 4457 // C++ [dcl.enum]p4: Following the closing brace of an 4458 // enum-specifier, each enumerator has the type of its 4459 // enumeration. 4460 ECD->setType(EnumType); 4461 else 4462 ECD->setType(NewTy); 4463 } 4464 4465 Enum->completeDefinition(Context, BestType); 4466} 4467 4468Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4469 ExprArg expr) { 4470 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 4471 4472 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 4473 Loc, AsmString); 4474 CurContext->addDecl(Context, New); 4475 return DeclPtrTy::make(New); 4476} 4477 4478void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 4479 SourceLocation PragmaLoc, 4480 SourceLocation NameLoc) { 4481 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 4482 4483 // FIXME: This implementation is an ugly hack! 4484 if (PrevDecl) { 4485 PrevDecl->addAttr(Context, ::new (Context) WeakAttr()); 4486 return; 4487 } 4488 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 4489 return; 4490} 4491 4492void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 4493 IdentifierInfo* AliasName, 4494 SourceLocation PragmaLoc, 4495 SourceLocation NameLoc, 4496 SourceLocation AliasNameLoc) { 4497 Decl *PrevDecl = LookupName(TUScope, Name, LookupOrdinaryName); 4498 4499 // FIXME: This implementation is an ugly hack! 4500 if (PrevDecl) { 4501 PrevDecl->addAttr(Context, ::new (Context) AliasAttr(AliasName->getName())); 4502 PrevDecl->addAttr(Context, ::new (Context) WeakAttr()); 4503 return; 4504 } 4505 Diag(PragmaLoc, diag::err_unsupported_pragma_weak); 4506 return; 4507} 4508