SemaDecl.cpp revision e8e4492eaea4328dfd968b28e73e2211ca649299
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/AST/StmtCXX.h" 22#include "clang/Parse/DeclSpec.h" 23#include "clang/Basic/TargetInfo.h" 24#include "clang/Basic/SourceManager.h" 25// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 26#include "clang/Lex/Preprocessor.h" 27#include "clang/Lex/HeaderSearch.h" 28#include "llvm/ADT/SmallSet.h" 29#include "llvm/ADT/STLExtras.h" 30#include <algorithm> 31#include <functional> 32using namespace clang; 33 34/// getDeclName - Return a pretty name for the specified decl if possible, or 35/// an empty string if not. This is used for pretty crash reporting. 36std::string Sema::getDeclName(DeclPtrTy d) { 37 Decl *D = d.getAs<Decl>(); 38 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 39 return DN->getQualifiedNameAsString(); 40 return ""; 41} 42 43Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 44 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 45} 46 47/// \brief If the identifier refers to a type name within this scope, 48/// return the declaration of that type. 49/// 50/// This routine performs ordinary name lookup of the identifier II 51/// within the given scope, with optional C++ scope specifier SS, to 52/// determine whether the name refers to a type. If so, returns an 53/// opaque pointer (actually a QualType) corresponding to that 54/// type. Otherwise, returns NULL. 55/// 56/// If name lookup results in an ambiguity, this routine will complain 57/// and then return NULL. 58Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 59 Scope *S, const CXXScopeSpec *SS) { 60 // C++ [temp.res]p3: 61 // A qualified-id that refers to a type and in which the 62 // nested-name-specifier depends on a template-parameter (14.6.2) 63 // shall be prefixed by the keyword typename to indicate that the 64 // qualified-id denotes a type, forming an 65 // elaborated-type-specifier (7.1.5.3). 66 // 67 // We therefore do not perform any name lookup up SS is a dependent 68 // scope name. FIXME: we will need to perform a special kind of 69 // lookup if the scope specifier names a member of the current 70 // instantiation. 71 if (SS && isDependentScopeSpecifier(*SS)) 72 return 0; 73 74 NamedDecl *IIDecl = 0; 75 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 76 false, false); 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 T = Context.getTypeDeclType(TD); 128 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 129 // Check whether we can use this interface. 130 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 131 132 T = Context.getObjCInterfaceType(IDecl); 133 } else 134 return 0; 135 136 if (SS) 137 T = getQualifiedNameType(*SS, T); 138 139 return T.getAsOpaquePtr(); 140 } 141 142 return 0; 143} 144 145/// isTagName() - This method is called *for error recovery purposes only* 146/// to determine if the specified name is a valid tag name ("struct foo"). If 147/// so, this returns the TST for the tag corresponding to it (TST_enum, 148/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 149/// where the user forgot to specify the tag. 150DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 151 // Do a tag name lookup in this scope. 152 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 153 if (R.getKind() == LookupResult::Found) 154 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 155 switch (TD->getTagKind()) { 156 case TagDecl::TK_struct: return DeclSpec::TST_struct; 157 case TagDecl::TK_union: return DeclSpec::TST_union; 158 case TagDecl::TK_class: return DeclSpec::TST_class; 159 case TagDecl::TK_enum: return DeclSpec::TST_enum; 160 } 161 } 162 163 return DeclSpec::TST_unspecified; 164} 165 166 167 168DeclContext *Sema::getContainingDC(DeclContext *DC) { 169 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 170 // A C++ out-of-line method will return to the file declaration context. 171 if (MD->isOutOfLineDefinition()) 172 return MD->getLexicalDeclContext(); 173 174 // A C++ inline method is parsed *after* the topmost class it was declared 175 // in is fully parsed (it's "complete"). 176 // The parsing of a C++ inline method happens at the declaration context of 177 // the topmost (non-nested) class it is lexically declared in. 178 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 179 DC = MD->getParent(); 180 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 181 DC = RD; 182 183 // Return the declaration context of the topmost class the inline method is 184 // declared in. 185 return DC; 186 } 187 188 if (isa<ObjCMethodDecl>(DC)) 189 return Context.getTranslationUnitDecl(); 190 191 return DC->getLexicalParent(); 192} 193 194void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 195 assert(getContainingDC(DC) == CurContext && 196 "The next DeclContext should be lexically contained in the current one."); 197 CurContext = DC; 198 S->setEntity(DC); 199} 200 201void Sema::PopDeclContext() { 202 assert(CurContext && "DeclContext imbalance!"); 203 204 CurContext = getContainingDC(CurContext); 205} 206 207/// \brief Determine whether we allow overloading of the function 208/// PrevDecl with another declaration. 209/// 210/// This routine determines whether overloading is possible, not 211/// whether some new function is actually an overload. It will return 212/// true in C++ (where we can always provide overloads) or, as an 213/// extension, in C when the previous function is already an 214/// overloaded function declaration or has the "overloadable" 215/// attribute. 216static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 217 if (Context.getLangOptions().CPlusPlus) 218 return true; 219 220 if (isa<OverloadedFunctionDecl>(PrevDecl)) 221 return true; 222 223 return PrevDecl->getAttr<OverloadableAttr>() != 0; 224} 225 226/// Add this decl to the scope shadowed decl chains. 227void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 228 // Move up the scope chain until we find the nearest enclosing 229 // non-transparent context. The declaration will be introduced into this 230 // scope. 231 while (S->getEntity() && 232 ((DeclContext *)S->getEntity())->isTransparentContext()) 233 S = S->getParent(); 234 235 S->AddDecl(DeclPtrTy::make(D)); 236 237 // Add scoped declarations into their context, so that they can be 238 // found later. Declarations without a context won't be inserted 239 // into any context. 240 CurContext->addDecl(Context, D); 241 242 // C++ [basic.scope]p4: 243 // -- exactly one declaration shall declare a class name or 244 // enumeration name that is not a typedef name and the other 245 // declarations shall all refer to the same object or 246 // enumerator, or all refer to functions and function templates; 247 // in this case the class name or enumeration name is hidden. 248 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 249 // We are pushing the name of a tag (enum or class). 250 if (CurContext->getLookupContext() 251 == TD->getDeclContext()->getLookupContext()) { 252 // We're pushing the tag into the current context, which might 253 // require some reshuffling in the identifier resolver. 254 IdentifierResolver::iterator 255 I = IdResolver.begin(TD->getDeclName()), 256 IEnd = IdResolver.end(); 257 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 258 NamedDecl *PrevDecl = *I; 259 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 260 PrevDecl = *I, ++I) { 261 if (TD->declarationReplaces(*I)) { 262 // This is a redeclaration. Remove it from the chain and 263 // break out, so that we'll add in the shadowed 264 // declaration. 265 S->RemoveDecl(DeclPtrTy::make(*I)); 266 if (PrevDecl == *I) { 267 IdResolver.RemoveDecl(*I); 268 IdResolver.AddDecl(TD); 269 return; 270 } else { 271 IdResolver.RemoveDecl(*I); 272 break; 273 } 274 } 275 } 276 277 // There is already a declaration with the same name in the same 278 // scope, which is not a tag declaration. It must be found 279 // before we find the new declaration, so insert the new 280 // declaration at the end of the chain. 281 IdResolver.AddShadowedDecl(TD, PrevDecl); 282 283 return; 284 } 285 } 286 } else if (isa<FunctionDecl>(D) && 287 AllowOverloadingOfFunction(D, Context)) { 288 // We are pushing the name of a function, which might be an 289 // overloaded name. 290 FunctionDecl *FD = cast<FunctionDecl>(D); 291 IdentifierResolver::iterator Redecl 292 = std::find_if(IdResolver.begin(FD->getDeclName()), 293 IdResolver.end(), 294 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 295 FD)); 296 if (Redecl != IdResolver.end() && 297 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 298 // There is already a declaration of a function on our 299 // IdResolver chain. Replace it with this declaration. 300 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 301 IdResolver.RemoveDecl(*Redecl); 302 } 303 } else if (isa<ObjCInterfaceDecl>(D)) { 304 // We're pushing an Objective-C interface into the current 305 // context. If there is already an alias declaration, remove it first. 306 for (IdentifierResolver::iterator 307 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 308 I != IEnd; ++I) { 309 if (isa<ObjCCompatibleAliasDecl>(*I)) { 310 S->RemoveDecl(DeclPtrTy::make(*I)); 311 IdResolver.RemoveDecl(*I); 312 break; 313 } 314 } 315 } 316 317 IdResolver.AddDecl(D); 318} 319 320void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 321 if (S->decl_empty()) return; 322 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 323 "Scope shouldn't contain decls!"); 324 325 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 326 I != E; ++I) { 327 Decl *TmpD = (*I).getAs<Decl>(); 328 assert(TmpD && "This decl didn't get pushed??"); 329 330 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 331 NamedDecl *D = cast<NamedDecl>(TmpD); 332 333 if (!D->getDeclName()) continue; 334 335 // Remove this name from our lexical scope. 336 IdResolver.RemoveDecl(D); 337 } 338} 339 340/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 341/// return 0 if one not found. 342ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 343 // The third "scope" argument is 0 since we aren't enabling lazy built-in 344 // creation from this context. 345 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 346 347 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 348} 349 350/// getNonFieldDeclScope - Retrieves the innermost scope, starting 351/// from S, where a non-field would be declared. This routine copes 352/// with the difference between C and C++ scoping rules in structs and 353/// unions. For example, the following code is well-formed in C but 354/// ill-formed in C++: 355/// @code 356/// struct S6 { 357/// enum { BAR } e; 358/// }; 359/// 360/// void test_S6() { 361/// struct S6 a; 362/// a.e = BAR; 363/// } 364/// @endcode 365/// For the declaration of BAR, this routine will return a different 366/// scope. The scope S will be the scope of the unnamed enumeration 367/// within S6. In C++, this routine will return the scope associated 368/// with S6, because the enumeration's scope is a transparent 369/// context but structures can contain non-field names. In C, this 370/// routine will return the translation unit scope, since the 371/// enumeration's scope is a transparent context and structures cannot 372/// contain non-field names. 373Scope *Sema::getNonFieldDeclScope(Scope *S) { 374 while (((S->getFlags() & Scope::DeclScope) == 0) || 375 (S->getEntity() && 376 ((DeclContext *)S->getEntity())->isTransparentContext()) || 377 (S->isClassScope() && !getLangOptions().CPlusPlus)) 378 S = S->getParent(); 379 return S; 380} 381 382void Sema::InitBuiltinVaListType() { 383 if (!Context.getBuiltinVaListType().isNull()) 384 return; 385 386 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 387 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 388 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 389 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 390} 391 392/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 393/// file scope. lazily create a decl for it. ForRedeclaration is true 394/// if we're creating this built-in in anticipation of redeclaring the 395/// built-in. 396NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 397 Scope *S, bool ForRedeclaration, 398 SourceLocation Loc) { 399 Builtin::ID BID = (Builtin::ID)bid; 400 401 if (Context.BuiltinInfo.hasVAListUse(BID)) 402 InitBuiltinVaListType(); 403 404 Builtin::Context::GetBuiltinTypeError Error; 405 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 406 switch (Error) { 407 case Builtin::Context::GE_None: 408 // Okay 409 break; 410 411 case Builtin::Context::GE_Missing_FILE: 412 if (ForRedeclaration) 413 Diag(Loc, diag::err_implicit_decl_requires_stdio) 414 << Context.BuiltinInfo.GetName(BID); 415 return 0; 416 } 417 418 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 419 Diag(Loc, diag::ext_implicit_lib_function_decl) 420 << Context.BuiltinInfo.GetName(BID) 421 << R; 422 if (Context.BuiltinInfo.getHeaderName(BID) && 423 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 424 != Diagnostic::Ignored) 425 Diag(Loc, diag::note_please_include_header) 426 << Context.BuiltinInfo.getHeaderName(BID) 427 << Context.BuiltinInfo.GetName(BID); 428 } 429 430 FunctionDecl *New = FunctionDecl::Create(Context, 431 Context.getTranslationUnitDecl(), 432 Loc, II, R, 433 FunctionDecl::Extern, false, 434 /*hasPrototype=*/true); 435 New->setImplicit(); 436 437 // Create Decl objects for each parameter, adding them to the 438 // FunctionDecl. 439 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 440 llvm::SmallVector<ParmVarDecl*, 16> Params; 441 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 442 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 443 FT->getArgType(i), VarDecl::None, 0)); 444 New->setParams(Context, &Params[0], Params.size()); 445 } 446 447 AddKnownFunctionAttributes(New); 448 449 // TUScope is the translation-unit scope to insert this function into. 450 // FIXME: This is hideous. We need to teach PushOnScopeChains to 451 // relate Scopes to DeclContexts, and probably eliminate CurContext 452 // entirely, but we're not there yet. 453 DeclContext *SavedContext = CurContext; 454 CurContext = Context.getTranslationUnitDecl(); 455 PushOnScopeChains(New, TUScope); 456 CurContext = SavedContext; 457 return New; 458} 459 460/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 461/// everything from the standard library is defined. 462NamespaceDecl *Sema::GetStdNamespace() { 463 if (!StdNamespace) { 464 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 465 DeclContext *Global = Context.getTranslationUnitDecl(); 466 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 467 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 468 } 469 return StdNamespace; 470} 471 472/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 473/// same name and scope as a previous declaration 'Old'. Figure out 474/// how to resolve this situation, merging decls or emitting 475/// diagnostics as appropriate. If there was an error, set New to be invalid. 476/// 477void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 478 // If either decl is known invalid already, set the new one to be invalid and 479 // don't bother doing any merging checks. 480 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 481 return New->setInvalidDecl(); 482 483 bool objc_types = false; 484 485 // Allow multiple definitions for ObjC built-in typedefs. 486 // FIXME: Verify the underlying types are equivalent! 487 if (getLangOptions().ObjC1) { 488 const IdentifierInfo *TypeID = New->getIdentifier(); 489 switch (TypeID->getLength()) { 490 default: break; 491 case 2: 492 if (!TypeID->isStr("id")) 493 break; 494 Context.setObjCIdType(Context.getTypeDeclType(New)); 495 objc_types = true; 496 break; 497 case 5: 498 if (!TypeID->isStr("Class")) 499 break; 500 Context.setObjCClassType(Context.getTypeDeclType(New)); 501 return; 502 case 3: 503 if (!TypeID->isStr("SEL")) 504 break; 505 Context.setObjCSelType(Context.getTypeDeclType(New)); 506 return; 507 case 8: 508 if (!TypeID->isStr("Protocol")) 509 break; 510 Context.setObjCProtoType(New->getUnderlyingType()); 511 return; 512 } 513 // Fall through - the typedef name was not a builtin type. 514 } 515 // Verify the old decl was also a type. 516 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 517 if (!Old) { 518 Diag(New->getLocation(), diag::err_redefinition_different_kind) 519 << New->getDeclName(); 520 if (OldD->getLocation().isValid()) 521 Diag(OldD->getLocation(), diag::note_previous_definition); 522 return New->setInvalidDecl(); 523 } 524 525 // Determine the "old" type we'll use for checking and diagnostics. 526 QualType OldType; 527 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 528 OldType = OldTypedef->getUnderlyingType(); 529 else 530 OldType = Context.getTypeDeclType(Old); 531 532 // If the typedef types are not identical, reject them in all languages and 533 // with any extensions enabled. 534 535 if (OldType != New->getUnderlyingType() && 536 Context.getCanonicalType(OldType) != 537 Context.getCanonicalType(New->getUnderlyingType())) { 538 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 539 << New->getUnderlyingType() << OldType; 540 if (Old->getLocation().isValid()) 541 Diag(Old->getLocation(), diag::note_previous_definition); 542 return New->setInvalidDecl(); 543 } 544 545 if (objc_types || getLangOptions().Microsoft) 546 return; 547 548 // C++ [dcl.typedef]p2: 549 // In a given non-class scope, a typedef specifier can be used to 550 // redefine the name of any type declared in that scope to refer 551 // to the type to which it already refers. 552 if (getLangOptions().CPlusPlus) { 553 if (!isa<CXXRecordDecl>(CurContext)) 554 return; 555 Diag(New->getLocation(), diag::err_redefinition) 556 << New->getDeclName(); 557 Diag(Old->getLocation(), diag::note_previous_definition); 558 return New->setInvalidDecl(); 559 } 560 561 // If we have a redefinition of a typedef in C, emit a warning. This warning 562 // is normally mapped to an error, but can be controlled with 563 // -Wtypedef-redefinition. If either the original was in a system header, 564 // don't emit this for compatibility with GCC. 565 if (PP.getDiagnostics().getSuppressSystemWarnings() && 566 Context.getSourceManager().isInSystemHeader(Old->getLocation())) 567 return; 568 569 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 570 << New->getDeclName(); 571 Diag(Old->getLocation(), diag::note_previous_definition); 572 return; 573} 574 575/// DeclhasAttr - returns true if decl Declaration already has the target 576/// attribute. 577static bool DeclHasAttr(const Decl *decl, const Attr *target) { 578 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 579 if (attr->getKind() == target->getKind()) 580 return true; 581 582 return false; 583} 584 585/// MergeAttributes - append attributes from the Old decl to the New one. 586static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 587 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 588 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 589 Attr *NewAttr = attr->clone(C); 590 NewAttr->setInherited(true); 591 New->addAttr(NewAttr); 592 } 593 } 594} 595 596/// Used in MergeFunctionDecl to keep track of function parameters in 597/// C. 598struct GNUCompatibleParamWarning { 599 ParmVarDecl *OldParm; 600 ParmVarDecl *NewParm; 601 QualType PromotedType; 602}; 603 604/// MergeFunctionDecl - We just parsed a function 'New' from 605/// declarator D which has the same name and scope as a previous 606/// declaration 'Old'. Figure out how to resolve this situation, 607/// merging decls or emitting diagnostics as appropriate. 608/// 609/// In C++, New and Old must be declarations that are not 610/// overloaded. Use IsOverload to determine whether New and Old are 611/// overloaded, and to select the Old declaration that New should be 612/// merged with. 613/// 614/// Returns true if there was an error, false otherwise. 615bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 616 assert(!isa<OverloadedFunctionDecl>(OldD) && 617 "Cannot merge with an overloaded function declaration"); 618 619 // Verify the old decl was also a function. 620 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 621 if (!Old) { 622 Diag(New->getLocation(), diag::err_redefinition_different_kind) 623 << New->getDeclName(); 624 Diag(OldD->getLocation(), diag::note_previous_definition); 625 return true; 626 } 627 628 // Determine whether the previous declaration was a definition, 629 // implicit declaration, or a declaration. 630 diag::kind PrevDiag; 631 if (Old->isThisDeclarationADefinition()) 632 PrevDiag = diag::note_previous_definition; 633 else if (Old->isImplicit()) 634 PrevDiag = diag::note_previous_implicit_declaration; 635 else 636 PrevDiag = diag::note_previous_declaration; 637 638 QualType OldQType = Context.getCanonicalType(Old->getType()); 639 QualType NewQType = Context.getCanonicalType(New->getType()); 640 641 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 642 New->getStorageClass() == FunctionDecl::Static && 643 Old->getStorageClass() != FunctionDecl::Static) { 644 Diag(New->getLocation(), diag::err_static_non_static) 645 << New; 646 Diag(Old->getLocation(), PrevDiag); 647 return true; 648 } 649 650 if (getLangOptions().CPlusPlus) { 651 // (C++98 13.1p2): 652 // Certain function declarations cannot be overloaded: 653 // -- Function declarations that differ only in the return type 654 // cannot be overloaded. 655 QualType OldReturnType 656 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 657 QualType NewReturnType 658 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 659 if (OldReturnType != NewReturnType) { 660 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 661 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 662 return true; 663 } 664 665 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 666 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 667 if (OldMethod && NewMethod && 668 OldMethod->getLexicalDeclContext() == 669 NewMethod->getLexicalDeclContext()) { 670 // -- Member function declarations with the same name and the 671 // same parameter types cannot be overloaded if any of them 672 // is a static member function declaration. 673 if (OldMethod->isStatic() || NewMethod->isStatic()) { 674 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 675 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 676 return true; 677 } 678 679 // C++ [class.mem]p1: 680 // [...] A member shall not be declared twice in the 681 // member-specification, except that a nested class or member 682 // class template can be declared and then later defined. 683 unsigned NewDiag; 684 if (isa<CXXConstructorDecl>(OldMethod)) 685 NewDiag = diag::err_constructor_redeclared; 686 else if (isa<CXXDestructorDecl>(NewMethod)) 687 NewDiag = diag::err_destructor_redeclared; 688 else if (isa<CXXConversionDecl>(NewMethod)) 689 NewDiag = diag::err_conv_function_redeclared; 690 else 691 NewDiag = diag::err_member_redeclared; 692 693 Diag(New->getLocation(), NewDiag); 694 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 695 } 696 697 // (C++98 8.3.5p3): 698 // All declarations for a function shall agree exactly in both the 699 // return type and the parameter-type-list. 700 if (OldQType == NewQType) 701 return MergeCompatibleFunctionDecls(New, Old); 702 703 // Fall through for conflicting redeclarations and redefinitions. 704 } 705 706 // C: Function types need to be compatible, not identical. This handles 707 // duplicate function decls like "void f(int); void f(enum X);" properly. 708 if (!getLangOptions().CPlusPlus && 709 Context.typesAreCompatible(OldQType, NewQType)) { 710 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 711 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 712 const FunctionProtoType *OldProto = 0; 713 if (isa<FunctionNoProtoType>(NewFuncType) && 714 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 715 // The old declaration provided a function prototype, but the 716 // new declaration does not. Merge in the prototype. 717 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 718 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 719 OldProto->arg_type_end()); 720 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 721 &ParamTypes[0], ParamTypes.size(), 722 OldProto->isVariadic(), 723 OldProto->getTypeQuals()); 724 New->setType(NewQType); 725 New->setInheritedPrototype(); 726 727 // Synthesize a parameter for each argument type. 728 llvm::SmallVector<ParmVarDecl*, 16> Params; 729 for (FunctionProtoType::arg_type_iterator 730 ParamType = OldProto->arg_type_begin(), 731 ParamEnd = OldProto->arg_type_end(); 732 ParamType != ParamEnd; ++ParamType) { 733 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 734 SourceLocation(), 0, 735 *ParamType, VarDecl::None, 736 0); 737 Param->setImplicit(); 738 Params.push_back(Param); 739 } 740 741 New->setParams(Context, &Params[0], Params.size()); 742 } 743 744 return MergeCompatibleFunctionDecls(New, Old); 745 } 746 747 // GNU C permits a K&R definition to follow a prototype declaration 748 // if the declared types of the parameters in the K&R definition 749 // match the types in the prototype declaration, even when the 750 // promoted types of the parameters from the K&R definition differ 751 // from the types in the prototype. GCC then keeps the types from 752 // the prototype. 753 if (!getLangOptions().CPlusPlus && 754 Old->hasPrototype() && !New->hasPrototype() && 755 New->getType()->getAsFunctionProtoType() && 756 Old->getNumParams() == New->getNumParams()) { 757 llvm::SmallVector<QualType, 16> ArgTypes; 758 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 759 const FunctionProtoType *OldProto 760 = Old->getType()->getAsFunctionProtoType(); 761 const FunctionProtoType *NewProto 762 = New->getType()->getAsFunctionProtoType(); 763 764 // Determine whether this is the GNU C extension. 765 bool GNUCompatible = 766 Context.typesAreCompatible(OldProto->getResultType(), 767 NewProto->getResultType()) && 768 (OldProto->isVariadic() == NewProto->isVariadic()); 769 for (unsigned Idx = 0, End = Old->getNumParams(); 770 GNUCompatible && Idx != End; ++Idx) { 771 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 772 ParmVarDecl *NewParm = New->getParamDecl(Idx); 773 if (Context.typesAreCompatible(OldParm->getType(), 774 NewProto->getArgType(Idx))) { 775 ArgTypes.push_back(NewParm->getType()); 776 } else if (Context.typesAreCompatible(OldParm->getType(), 777 NewParm->getType())) { 778 GNUCompatibleParamWarning Warn 779 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 780 Warnings.push_back(Warn); 781 ArgTypes.push_back(NewParm->getType()); 782 } else 783 GNUCompatible = false; 784 } 785 786 if (GNUCompatible) { 787 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 788 Diag(Warnings[Warn].NewParm->getLocation(), 789 diag::ext_param_promoted_not_compatible_with_prototype) 790 << Warnings[Warn].PromotedType 791 << Warnings[Warn].OldParm->getType(); 792 Diag(Warnings[Warn].OldParm->getLocation(), 793 diag::note_previous_declaration); 794 } 795 796 New->setType(Context.getFunctionType(NewProto->getResultType(), 797 &ArgTypes[0], ArgTypes.size(), 798 NewProto->isVariadic(), 799 NewProto->getTypeQuals())); 800 return MergeCompatibleFunctionDecls(New, Old); 801 } 802 803 // Fall through to diagnose conflicting types. 804 } 805 806 // A function that has already been declared has been redeclared or defined 807 // with a different type- show appropriate diagnostic 808 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 809 // The user has declared a builtin function with an incompatible 810 // signature. 811 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 812 // The function the user is redeclaring is a library-defined 813 // function like 'malloc' or 'printf'. Warn about the 814 // redeclaration, then pretend that we don't know about this 815 // library built-in. 816 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 817 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 818 << Old << Old->getType(); 819 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 820 Old->setInvalidDecl(); 821 return false; 822 } 823 824 PrevDiag = diag::note_previous_builtin_declaration; 825 } 826 827 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 828 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 829 return true; 830} 831 832/// \brief Completes the merge of two function declarations that are 833/// known to be compatible. 834/// 835/// This routine handles the merging of attributes and other 836/// properties of function declarations form the old declaration to 837/// the new declaration, once we know that New is in fact a 838/// redeclaration of Old. 839/// 840/// \returns false 841bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 842 // Merge the attributes 843 MergeAttributes(New, Old, Context); 844 845 // Merge the storage class. 846 if (Old->getStorageClass() != FunctionDecl::Extern) 847 New->setStorageClass(Old->getStorageClass()); 848 849 // Merge "inline" 850 if (Old->isInline()) 851 New->setInline(true); 852 853 // If this function declaration by itself qualifies as a C99 inline 854 // definition (C99 6.7.4p6), but the previous definition did not, 855 // then the function is not a C99 inline definition. 856 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 857 New->setC99InlineDefinition(false); 858 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 859 // Mark all preceding definitions as not being C99 inline definitions. 860 for (const FunctionDecl *Prev = Old; Prev; 861 Prev = Prev->getPreviousDeclaration()) 862 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 863 } 864 865 // Merge "pure" flag. 866 if (Old->isPure()) 867 New->setPure(); 868 869 // Merge the "deleted" flag. 870 if (Old->isDeleted()) 871 New->setDeleted(); 872 873 if (getLangOptions().CPlusPlus) 874 return MergeCXXFunctionDecl(New, Old); 875 876 return false; 877} 878 879/// MergeVarDecl - We just parsed a variable 'New' which has the same name 880/// and scope as a previous declaration 'Old'. Figure out how to resolve this 881/// situation, merging decls or emitting diagnostics as appropriate. 882/// 883/// Tentative definition rules (C99 6.9.2p2) are checked by 884/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 885/// definitions here, since the initializer hasn't been attached. 886/// 887void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 888 // If either decl is invalid, make sure the new one is marked invalid and 889 // don't do any other checking. 890 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 891 return New->setInvalidDecl(); 892 893 // Verify the old decl was also a variable. 894 VarDecl *Old = dyn_cast<VarDecl>(OldD); 895 if (!Old) { 896 Diag(New->getLocation(), diag::err_redefinition_different_kind) 897 << New->getDeclName(); 898 Diag(OldD->getLocation(), diag::note_previous_definition); 899 return New->setInvalidDecl(); 900 } 901 902 MergeAttributes(New, Old, Context); 903 904 // Merge the types 905 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 906 if (MergedT.isNull()) { 907 Diag(New->getLocation(), diag::err_redefinition_different_type) 908 << New->getDeclName(); 909 Diag(Old->getLocation(), diag::note_previous_definition); 910 return New->setInvalidDecl(); 911 } 912 New->setType(MergedT); 913 914 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 915 if (New->getStorageClass() == VarDecl::Static && 916 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 917 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 918 Diag(Old->getLocation(), diag::note_previous_definition); 919 return New->setInvalidDecl(); 920 } 921 // C99 6.2.2p4: 922 // For an identifier declared with the storage-class specifier 923 // extern in a scope in which a prior declaration of that 924 // identifier is visible,23) if the prior declaration specifies 925 // internal or external linkage, the linkage of the identifier at 926 // the later declaration is the same as the linkage specified at 927 // the prior declaration. If no prior declaration is visible, or 928 // if the prior declaration specifies no linkage, then the 929 // identifier has external linkage. 930 if (New->hasExternalStorage() && Old->hasLinkage()) 931 /* Okay */; 932 else if (New->getStorageClass() != VarDecl::Static && 933 Old->getStorageClass() == VarDecl::Static) { 934 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 935 Diag(Old->getLocation(), diag::note_previous_definition); 936 return New->setInvalidDecl(); 937 } 938 939 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 940 941 // FIXME: The test for external storage here seems wrong? We still 942 // need to check for mismatches. 943 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 944 // Don't complain about out-of-line definitions of static members. 945 !(Old->getLexicalDeclContext()->isRecord() && 946 !New->getLexicalDeclContext()->isRecord())) { 947 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 948 Diag(Old->getLocation(), diag::note_previous_definition); 949 return New->setInvalidDecl(); 950 } 951 952 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 953 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 954 Diag(Old->getLocation(), diag::note_previous_definition); 955 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 956 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 957 Diag(Old->getLocation(), diag::note_previous_definition); 958 } 959 960 // Keep a chain of previous declarations. 961 New->setPreviousDeclaration(Old); 962} 963 964/// CheckParmsForFunctionDef - Check that the parameters of the given 965/// function are appropriate for the definition of a function. This 966/// takes care of any checks that cannot be performed on the 967/// declaration itself, e.g., that the types of each of the function 968/// parameters are complete. 969bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 970 bool HasInvalidParm = false; 971 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 972 ParmVarDecl *Param = FD->getParamDecl(p); 973 974 // C99 6.7.5.3p4: the parameters in a parameter type list in a 975 // function declarator that is part of a function definition of 976 // that function shall not have incomplete type. 977 // 978 // This is also C++ [dcl.fct]p6. 979 if (!Param->isInvalidDecl() && 980 RequireCompleteType(Param->getLocation(), Param->getType(), 981 diag::err_typecheck_decl_incomplete_type)) { 982 Param->setInvalidDecl(); 983 HasInvalidParm = true; 984 } 985 986 // C99 6.9.1p5: If the declarator includes a parameter type list, the 987 // declaration of each parameter shall include an identifier. 988 if (Param->getIdentifier() == 0 && 989 !Param->isImplicit() && 990 !getLangOptions().CPlusPlus) 991 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 992 } 993 994 return HasInvalidParm; 995} 996 997/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 998/// no declarator (e.g. "struct foo;") is parsed. 999Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1000 // FIXME: Error on auto/register at file scope 1001 // FIXME: Error on inline/virtual/explicit 1002 // FIXME: Error on invalid restrict 1003 // FIXME: Warn on useless __thread 1004 // FIXME: Warn on useless const/volatile 1005 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1006 // FIXME: Warn on useless attributes 1007 1008 TagDecl *Tag = 0; 1009 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1010 DS.getTypeSpecType() == DeclSpec::TST_struct || 1011 DS.getTypeSpecType() == DeclSpec::TST_union || 1012 DS.getTypeSpecType() == DeclSpec::TST_enum) 1013 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1014 1015 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1016 if (!Record->getDeclName() && Record->isDefinition() && 1017 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1018 if (getLangOptions().CPlusPlus || 1019 Record->getDeclContext()->isRecord()) 1020 return BuildAnonymousStructOrUnion(S, DS, Record); 1021 1022 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1023 << DS.getSourceRange(); 1024 } 1025 1026 // Microsoft allows unnamed struct/union fields. Don't complain 1027 // about them. 1028 // FIXME: Should we support Microsoft's extensions in this area? 1029 if (Record->getDeclName() && getLangOptions().Microsoft) 1030 return DeclPtrTy::make(Tag); 1031 } 1032 1033 if (!DS.isMissingDeclaratorOk() && 1034 DS.getTypeSpecType() != DeclSpec::TST_error) { 1035 // Warn about typedefs of enums without names, since this is an 1036 // extension in both Microsoft an GNU. 1037 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1038 Tag && isa<EnumDecl>(Tag)) { 1039 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1040 << DS.getSourceRange(); 1041 return DeclPtrTy::make(Tag); 1042 } 1043 1044 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1045 << DS.getSourceRange(); 1046 return DeclPtrTy(); 1047 } 1048 1049 return DeclPtrTy::make(Tag); 1050} 1051 1052/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1053/// anonymous struct or union AnonRecord into the owning context Owner 1054/// and scope S. This routine will be invoked just after we realize 1055/// that an unnamed union or struct is actually an anonymous union or 1056/// struct, e.g., 1057/// 1058/// @code 1059/// union { 1060/// int i; 1061/// float f; 1062/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1063/// // f into the surrounding scope.x 1064/// @endcode 1065/// 1066/// This routine is recursive, injecting the names of nested anonymous 1067/// structs/unions into the owning context and scope as well. 1068bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1069 RecordDecl *AnonRecord) { 1070 bool Invalid = false; 1071 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1072 FEnd = AnonRecord->field_end(Context); 1073 F != FEnd; ++F) { 1074 if ((*F)->getDeclName()) { 1075 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1076 LookupOrdinaryName, true); 1077 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1078 // C++ [class.union]p2: 1079 // The names of the members of an anonymous union shall be 1080 // distinct from the names of any other entity in the 1081 // scope in which the anonymous union is declared. 1082 unsigned diagKind 1083 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1084 : diag::err_anonymous_struct_member_redecl; 1085 Diag((*F)->getLocation(), diagKind) 1086 << (*F)->getDeclName(); 1087 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1088 Invalid = true; 1089 } else { 1090 // C++ [class.union]p2: 1091 // For the purpose of name lookup, after the anonymous union 1092 // definition, the members of the anonymous union are 1093 // considered to have been defined in the scope in which the 1094 // anonymous union is declared. 1095 Owner->makeDeclVisibleInContext(Context, *F); 1096 S->AddDecl(DeclPtrTy::make(*F)); 1097 IdResolver.AddDecl(*F); 1098 } 1099 } else if (const RecordType *InnerRecordType 1100 = (*F)->getType()->getAsRecordType()) { 1101 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1102 if (InnerRecord->isAnonymousStructOrUnion()) 1103 Invalid = Invalid || 1104 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1105 } 1106 } 1107 1108 return Invalid; 1109} 1110 1111/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1112/// anonymous structure or union. Anonymous unions are a C++ feature 1113/// (C++ [class.union]) and a GNU C extension; anonymous structures 1114/// are a GNU C and GNU C++ extension. 1115Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1116 RecordDecl *Record) { 1117 DeclContext *Owner = Record->getDeclContext(); 1118 1119 // Diagnose whether this anonymous struct/union is an extension. 1120 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1121 Diag(Record->getLocation(), diag::ext_anonymous_union); 1122 else if (!Record->isUnion()) 1123 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1124 1125 // C and C++ require different kinds of checks for anonymous 1126 // structs/unions. 1127 bool Invalid = false; 1128 if (getLangOptions().CPlusPlus) { 1129 const char* PrevSpec = 0; 1130 // C++ [class.union]p3: 1131 // Anonymous unions declared in a named namespace or in the 1132 // global namespace shall be declared static. 1133 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1134 (isa<TranslationUnitDecl>(Owner) || 1135 (isa<NamespaceDecl>(Owner) && 1136 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1137 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1138 Invalid = true; 1139 1140 // Recover by adding 'static'. 1141 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1142 } 1143 // C++ [class.union]p3: 1144 // A storage class is not allowed in a declaration of an 1145 // anonymous union in a class scope. 1146 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1147 isa<RecordDecl>(Owner)) { 1148 Diag(DS.getStorageClassSpecLoc(), 1149 diag::err_anonymous_union_with_storage_spec); 1150 Invalid = true; 1151 1152 // Recover by removing the storage specifier. 1153 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1154 PrevSpec); 1155 } 1156 1157 // C++ [class.union]p2: 1158 // The member-specification of an anonymous union shall only 1159 // define non-static data members. [Note: nested types and 1160 // functions cannot be declared within an anonymous union. ] 1161 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1162 MemEnd = Record->decls_end(Context); 1163 Mem != MemEnd; ++Mem) { 1164 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1165 // C++ [class.union]p3: 1166 // An anonymous union shall not have private or protected 1167 // members (clause 11). 1168 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1169 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1170 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1171 Invalid = true; 1172 } 1173 } else if ((*Mem)->isImplicit()) { 1174 // Any implicit members are fine. 1175 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1176 // This is a type that showed up in an 1177 // elaborated-type-specifier inside the anonymous struct or 1178 // union, but which actually declares a type outside of the 1179 // anonymous struct or union. It's okay. 1180 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1181 if (!MemRecord->isAnonymousStructOrUnion() && 1182 MemRecord->getDeclName()) { 1183 // This is a nested type declaration. 1184 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1185 << (int)Record->isUnion(); 1186 Invalid = true; 1187 } 1188 } else { 1189 // We have something that isn't a non-static data 1190 // member. Complain about it. 1191 unsigned DK = diag::err_anonymous_record_bad_member; 1192 if (isa<TypeDecl>(*Mem)) 1193 DK = diag::err_anonymous_record_with_type; 1194 else if (isa<FunctionDecl>(*Mem)) 1195 DK = diag::err_anonymous_record_with_function; 1196 else if (isa<VarDecl>(*Mem)) 1197 DK = diag::err_anonymous_record_with_static; 1198 Diag((*Mem)->getLocation(), DK) 1199 << (int)Record->isUnion(); 1200 Invalid = true; 1201 } 1202 } 1203 } 1204 1205 if (!Record->isUnion() && !Owner->isRecord()) { 1206 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1207 << (int)getLangOptions().CPlusPlus; 1208 Invalid = true; 1209 } 1210 1211 // Create a declaration for this anonymous struct/union. 1212 NamedDecl *Anon = 0; 1213 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1214 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1215 /*IdentifierInfo=*/0, 1216 Context.getTypeDeclType(Record), 1217 /*BitWidth=*/0, /*Mutable=*/false); 1218 Anon->setAccess(AS_public); 1219 if (getLangOptions().CPlusPlus) 1220 FieldCollector->Add(cast<FieldDecl>(Anon)); 1221 } else { 1222 VarDecl::StorageClass SC; 1223 switch (DS.getStorageClassSpec()) { 1224 default: assert(0 && "Unknown storage class!"); 1225 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1226 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1227 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1228 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1229 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1230 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1231 case DeclSpec::SCS_mutable: 1232 // mutable can only appear on non-static class members, so it's always 1233 // an error here 1234 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1235 Invalid = true; 1236 SC = VarDecl::None; 1237 break; 1238 } 1239 1240 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1241 /*IdentifierInfo=*/0, 1242 Context.getTypeDeclType(Record), 1243 SC, DS.getSourceRange().getBegin()); 1244 } 1245 Anon->setImplicit(); 1246 1247 // Add the anonymous struct/union object to the current 1248 // context. We'll be referencing this object when we refer to one of 1249 // its members. 1250 Owner->addDecl(Context, Anon); 1251 1252 // Inject the members of the anonymous struct/union into the owning 1253 // context and into the identifier resolver chain for name lookup 1254 // purposes. 1255 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1256 Invalid = true; 1257 1258 // Mark this as an anonymous struct/union type. Note that we do not 1259 // do this until after we have already checked and injected the 1260 // members of this anonymous struct/union type, because otherwise 1261 // the members could be injected twice: once by DeclContext when it 1262 // builds its lookup table, and once by 1263 // InjectAnonymousStructOrUnionMembers. 1264 Record->setAnonymousStructOrUnion(true); 1265 1266 if (Invalid) 1267 Anon->setInvalidDecl(); 1268 1269 return DeclPtrTy::make(Anon); 1270} 1271 1272 1273/// GetNameForDeclarator - Determine the full declaration name for the 1274/// given Declarator. 1275DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1276 switch (D.getKind()) { 1277 case Declarator::DK_Abstract: 1278 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1279 return DeclarationName(); 1280 1281 case Declarator::DK_Normal: 1282 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1283 return DeclarationName(D.getIdentifier()); 1284 1285 case Declarator::DK_Constructor: { 1286 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1287 Ty = Context.getCanonicalType(Ty); 1288 return Context.DeclarationNames.getCXXConstructorName(Ty); 1289 } 1290 1291 case Declarator::DK_Destructor: { 1292 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1293 Ty = Context.getCanonicalType(Ty); 1294 return Context.DeclarationNames.getCXXDestructorName(Ty); 1295 } 1296 1297 case Declarator::DK_Conversion: { 1298 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1299 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1300 Ty = Context.getCanonicalType(Ty); 1301 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1302 } 1303 1304 case Declarator::DK_Operator: 1305 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1306 return Context.DeclarationNames.getCXXOperatorName( 1307 D.getOverloadedOperator()); 1308 } 1309 1310 assert(false && "Unknown name kind"); 1311 return DeclarationName(); 1312} 1313 1314/// isNearlyMatchingFunction - Determine whether the C++ functions 1315/// Declaration and Definition are "nearly" matching. This heuristic 1316/// is used to improve diagnostics in the case where an out-of-line 1317/// function definition doesn't match any declaration within 1318/// the class or namespace. 1319static bool isNearlyMatchingFunction(ASTContext &Context, 1320 FunctionDecl *Declaration, 1321 FunctionDecl *Definition) { 1322 if (Declaration->param_size() != Definition->param_size()) 1323 return false; 1324 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1325 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1326 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1327 1328 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1329 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1330 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1331 return false; 1332 } 1333 1334 return true; 1335} 1336 1337Sema::DeclPtrTy 1338Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1339 DeclarationName Name = GetNameForDeclarator(D); 1340 1341 // All of these full declarators require an identifier. If it doesn't have 1342 // one, the ParsedFreeStandingDeclSpec action should be used. 1343 if (!Name) { 1344 if (!D.isInvalidType()) // Reject this if we think it is valid. 1345 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1346 diag::err_declarator_need_ident) 1347 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1348 return DeclPtrTy(); 1349 } 1350 1351 // The scope passed in may not be a decl scope. Zip up the scope tree until 1352 // we find one that is. 1353 while ((S->getFlags() & Scope::DeclScope) == 0 || 1354 (S->getFlags() & Scope::TemplateParamScope) != 0) 1355 S = S->getParent(); 1356 1357 DeclContext *DC; 1358 NamedDecl *PrevDecl; 1359 NamedDecl *New; 1360 1361 QualType R = GetTypeForDeclarator(D, S); 1362 1363 // See if this is a redefinition of a variable in the same scope. 1364 if (D.getCXXScopeSpec().isInvalid()) { 1365 DC = CurContext; 1366 PrevDecl = 0; 1367 D.setInvalidType(); 1368 } else if (!D.getCXXScopeSpec().isSet()) { 1369 LookupNameKind NameKind = LookupOrdinaryName; 1370 1371 // If the declaration we're planning to build will be a function 1372 // or object with linkage, then look for another declaration with 1373 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1374 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1375 /* Do nothing*/; 1376 else if (R->isFunctionType()) { 1377 if (CurContext->isFunctionOrMethod()) 1378 NameKind = LookupRedeclarationWithLinkage; 1379 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1380 NameKind = LookupRedeclarationWithLinkage; 1381 1382 DC = CurContext; 1383 PrevDecl = LookupName(S, Name, NameKind, true, 1384 D.getDeclSpec().getStorageClassSpec() != 1385 DeclSpec::SCS_static, 1386 D.getIdentifierLoc()); 1387 } else { // Something like "int foo::x;" 1388 DC = computeDeclContext(D.getCXXScopeSpec()); 1389 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1390 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1391 1392 // C++ 7.3.1.2p2: 1393 // Members (including explicit specializations of templates) of a named 1394 // namespace can also be defined outside that namespace by explicit 1395 // qualification of the name being defined, provided that the entity being 1396 // defined was already declared in the namespace and the definition appears 1397 // after the point of declaration in a namespace that encloses the 1398 // declarations namespace. 1399 // 1400 // Note that we only check the context at this point. We don't yet 1401 // have enough information to make sure that PrevDecl is actually 1402 // the declaration we want to match. For example, given: 1403 // 1404 // class X { 1405 // void f(); 1406 // void f(float); 1407 // }; 1408 // 1409 // void X::f(int) { } // ill-formed 1410 // 1411 // In this case, PrevDecl will point to the overload set 1412 // containing the two f's declared in X, but neither of them 1413 // matches. 1414 1415 // First check whether we named the global scope. 1416 if (isa<TranslationUnitDecl>(DC)) { 1417 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1418 << Name << D.getCXXScopeSpec().getRange(); 1419 } else if (!CurContext->Encloses(DC)) { 1420 // The qualifying scope doesn't enclose the original declaration. 1421 // Emit diagnostic based on current scope. 1422 SourceLocation L = D.getIdentifierLoc(); 1423 SourceRange R = D.getCXXScopeSpec().getRange(); 1424 if (isa<FunctionDecl>(CurContext)) 1425 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1426 else 1427 Diag(L, diag::err_invalid_declarator_scope) 1428 << Name << cast<NamedDecl>(DC) << R; 1429 D.setInvalidType(); 1430 } 1431 } 1432 1433 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1434 // Maybe we will complain about the shadowed template parameter. 1435 if (!D.isInvalidType()) 1436 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1437 D.setInvalidType(); 1438 1439 // Just pretend that we didn't see the previous declaration. 1440 PrevDecl = 0; 1441 } 1442 1443 // In C++, the previous declaration we find might be a tag type 1444 // (class or enum). In this case, the new declaration will hide the 1445 // tag type. Note that this does does not apply if we're declaring a 1446 // typedef (C++ [dcl.typedef]p4). 1447 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1448 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1449 PrevDecl = 0; 1450 1451 bool Redeclaration = false; 1452 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1453 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1454 } else if (R->isFunctionType()) { 1455 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1456 IsFunctionDefinition, Redeclaration); 1457 } else { 1458 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1459 } 1460 1461 if (New == 0) 1462 return DeclPtrTy(); 1463 1464 // If this has an identifier and is not an invalid redeclaration, 1465 // add it to the scope stack. 1466 if (Name && !(Redeclaration && New->isInvalidDecl())) 1467 PushOnScopeChains(New, S); 1468 1469 return DeclPtrTy::make(New); 1470} 1471 1472/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1473/// types into constant array types in certain situations which would otherwise 1474/// be errors (for GCC compatibility). 1475static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1476 ASTContext &Context, 1477 bool &SizeIsNegative) { 1478 // This method tries to turn a variable array into a constant 1479 // array even when the size isn't an ICE. This is necessary 1480 // for compatibility with code that depends on gcc's buggy 1481 // constant expression folding, like struct {char x[(int)(char*)2];} 1482 SizeIsNegative = false; 1483 1484 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1485 QualType Pointee = PTy->getPointeeType(); 1486 QualType FixedType = 1487 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1488 if (FixedType.isNull()) return FixedType; 1489 FixedType = Context.getPointerType(FixedType); 1490 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1491 return FixedType; 1492 } 1493 1494 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1495 if (!VLATy) 1496 return QualType(); 1497 // FIXME: We should probably handle this case 1498 if (VLATy->getElementType()->isVariablyModifiedType()) 1499 return QualType(); 1500 1501 Expr::EvalResult EvalResult; 1502 if (!VLATy->getSizeExpr() || 1503 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1504 !EvalResult.Val.isInt()) 1505 return QualType(); 1506 1507 llvm::APSInt &Res = EvalResult.Val.getInt(); 1508 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1509 return Context.getConstantArrayType(VLATy->getElementType(), 1510 Res, ArrayType::Normal, 0); 1511 1512 SizeIsNegative = true; 1513 return QualType(); 1514} 1515 1516/// \brief Register the given locally-scoped external C declaration so 1517/// that it can be found later for redeclarations 1518void 1519Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1520 Scope *S) { 1521 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1522 "Decl is not a locally-scoped decl!"); 1523 // Note that we have a locally-scoped external with this name. 1524 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1525 1526 if (!PrevDecl) 1527 return; 1528 1529 // If there was a previous declaration of this variable, it may be 1530 // in our identifier chain. Update the identifier chain with the new 1531 // declaration. 1532 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1533 // The previous declaration was found on the identifer resolver 1534 // chain, so remove it from its scope. 1535 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1536 S = S->getParent(); 1537 1538 if (S) 1539 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1540 } 1541} 1542 1543/// \brief Diagnose function specifiers on a declaration of an identifier that 1544/// does not identify a function. 1545void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1546 // FIXME: We should probably indicate the identifier in question to avoid 1547 // confusion for constructs like "inline int a(), b;" 1548 if (D.getDeclSpec().isInlineSpecified()) 1549 Diag(D.getDeclSpec().getInlineSpecLoc(), 1550 diag::err_inline_non_function); 1551 1552 if (D.getDeclSpec().isVirtualSpecified()) 1553 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1554 diag::err_virtual_non_function); 1555 1556 if (D.getDeclSpec().isExplicitSpecified()) 1557 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1558 diag::err_explicit_non_function); 1559} 1560 1561NamedDecl* 1562Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1563 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1564 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1565 if (D.getCXXScopeSpec().isSet()) { 1566 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1567 << D.getCXXScopeSpec().getRange(); 1568 D.setInvalidType(); 1569 // Pretend we didn't see the scope specifier. 1570 DC = 0; 1571 } 1572 1573 if (getLangOptions().CPlusPlus) { 1574 // Check that there are no default arguments (C++ only). 1575 CheckExtraCXXDefaultArguments(D); 1576 } 1577 1578 DiagnoseFunctionSpecifiers(D); 1579 1580 if (D.getDeclSpec().isThreadSpecified()) 1581 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1582 1583 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1584 if (!NewTD) return 0; 1585 1586 if (D.isInvalidType()) 1587 NewTD->setInvalidDecl(); 1588 1589 // Handle attributes prior to checking for duplicates in MergeVarDecl 1590 ProcessDeclAttributes(NewTD, D); 1591 // Merge the decl with the existing one if appropriate. If the decl is 1592 // in an outer scope, it isn't the same thing. 1593 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1594 Redeclaration = true; 1595 MergeTypeDefDecl(NewTD, PrevDecl); 1596 } 1597 1598 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1599 // then it shall have block scope. 1600 QualType T = NewTD->getUnderlyingType(); 1601 if (T->isVariablyModifiedType()) { 1602 CurFunctionNeedsScopeChecking = true; 1603 1604 if (S->getFnParent() == 0) { 1605 bool SizeIsNegative; 1606 QualType FixedTy = 1607 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1608 if (!FixedTy.isNull()) { 1609 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1610 NewTD->setUnderlyingType(FixedTy); 1611 } else { 1612 if (SizeIsNegative) 1613 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1614 else if (T->isVariableArrayType()) 1615 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1616 else 1617 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1618 NewTD->setInvalidDecl(); 1619 } 1620 } 1621 } 1622 return NewTD; 1623} 1624 1625/// \brief Determines whether the given declaration is an out-of-scope 1626/// previous declaration. 1627/// 1628/// This routine should be invoked when name lookup has found a 1629/// previous declaration (PrevDecl) that is not in the scope where a 1630/// new declaration by the same name is being introduced. If the new 1631/// declaration occurs in a local scope, previous declarations with 1632/// linkage may still be considered previous declarations (C99 1633/// 6.2.2p4-5, C++ [basic.link]p6). 1634/// 1635/// \param PrevDecl the previous declaration found by name 1636/// lookup 1637/// 1638/// \param DC the context in which the new declaration is being 1639/// declared. 1640/// 1641/// \returns true if PrevDecl is an out-of-scope previous declaration 1642/// for a new delcaration with the same name. 1643static bool 1644isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1645 ASTContext &Context) { 1646 if (!PrevDecl) 1647 return 0; 1648 1649 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1650 // case we need to check each of the overloaded functions. 1651 if (!PrevDecl->hasLinkage()) 1652 return false; 1653 1654 if (Context.getLangOptions().CPlusPlus) { 1655 // C++ [basic.link]p6: 1656 // If there is a visible declaration of an entity with linkage 1657 // having the same name and type, ignoring entities declared 1658 // outside the innermost enclosing namespace scope, the block 1659 // scope declaration declares that same entity and receives the 1660 // linkage of the previous declaration. 1661 DeclContext *OuterContext = DC->getLookupContext(); 1662 if (!OuterContext->isFunctionOrMethod()) 1663 // This rule only applies to block-scope declarations. 1664 return false; 1665 else { 1666 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1667 if (PrevOuterContext->isRecord()) 1668 // We found a member function: ignore it. 1669 return false; 1670 else { 1671 // Find the innermost enclosing namespace for the new and 1672 // previous declarations. 1673 while (!OuterContext->isFileContext()) 1674 OuterContext = OuterContext->getParent(); 1675 while (!PrevOuterContext->isFileContext()) 1676 PrevOuterContext = PrevOuterContext->getParent(); 1677 1678 // The previous declaration is in a different namespace, so it 1679 // isn't the same function. 1680 if (OuterContext->getPrimaryContext() != 1681 PrevOuterContext->getPrimaryContext()) 1682 return false; 1683 } 1684 } 1685 } 1686 1687 return true; 1688} 1689 1690NamedDecl* 1691Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1692 QualType R,NamedDecl* PrevDecl, 1693 bool &Redeclaration) { 1694 DeclarationName Name = GetNameForDeclarator(D); 1695 1696 // Check that there are no default arguments (C++ only). 1697 if (getLangOptions().CPlusPlus) 1698 CheckExtraCXXDefaultArguments(D); 1699 1700 VarDecl *NewVD; 1701 VarDecl::StorageClass SC; 1702 switch (D.getDeclSpec().getStorageClassSpec()) { 1703 default: assert(0 && "Unknown storage class!"); 1704 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1705 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1706 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1707 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1708 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1709 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1710 case DeclSpec::SCS_mutable: 1711 // mutable can only appear on non-static class members, so it's always 1712 // an error here 1713 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1714 D.setInvalidType(); 1715 SC = VarDecl::None; 1716 break; 1717 } 1718 1719 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1720 if (!II) { 1721 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1722 << Name.getAsString(); 1723 return 0; 1724 } 1725 1726 DiagnoseFunctionSpecifiers(D); 1727 1728 if (!DC->isRecord() && S->getFnParent() == 0) { 1729 // C99 6.9p2: The storage-class specifiers auto and register shall not 1730 // appear in the declaration specifiers in an external declaration. 1731 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1732 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1733 D.setInvalidType(); 1734 } 1735 } 1736 if (DC->isRecord() && !CurContext->isRecord()) { 1737 // This is an out-of-line definition of a static data member. 1738 if (SC == VarDecl::Static) { 1739 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1740 diag::err_static_out_of_line) 1741 << CodeModificationHint::CreateRemoval( 1742 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1743 } else if (SC == VarDecl::None) 1744 SC = VarDecl::Static; 1745 } 1746 1747 // The variable can not 1748 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1749 II, R, SC, 1750 // FIXME: Move to DeclGroup... 1751 D.getDeclSpec().getSourceRange().getBegin()); 1752 1753 if (D.isInvalidType()) 1754 NewVD->setInvalidDecl(); 1755 1756 if (D.getDeclSpec().isThreadSpecified()) { 1757 if (NewVD->hasLocalStorage()) 1758 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1759 else if (!Context.Target.isTLSSupported()) 1760 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1761 else 1762 NewVD->setThreadSpecified(true); 1763 } 1764 1765 // Set the lexical context. If the declarator has a C++ scope specifier, the 1766 // lexical context will be different from the semantic context. 1767 NewVD->setLexicalDeclContext(CurContext); 1768 1769 // Handle attributes prior to checking for duplicates in MergeVarDecl 1770 ProcessDeclAttributes(NewVD, D); 1771 1772 // Handle GNU asm-label extension (encoded as an attribute). 1773 if (Expr *E = (Expr*) D.getAsmLabel()) { 1774 // The parser guarantees this is a string. 1775 StringLiteral *SE = cast<StringLiteral>(E); 1776 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1777 SE->getByteLength()))); 1778 } 1779 1780 // If name lookup finds a previous declaration that is not in the 1781 // same scope as the new declaration, this may still be an 1782 // acceptable redeclaration. 1783 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1784 !(NewVD->hasLinkage() && 1785 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1786 PrevDecl = 0; 1787 1788 // Merge the decl with the existing one if appropriate. 1789 if (PrevDecl) { 1790 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1791 // The user tried to define a non-static data member 1792 // out-of-line (C++ [dcl.meaning]p1). 1793 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1794 << D.getCXXScopeSpec().getRange(); 1795 PrevDecl = 0; 1796 NewVD->setInvalidDecl(); 1797 } 1798 } else if (D.getCXXScopeSpec().isSet()) { 1799 // No previous declaration in the qualifying scope. 1800 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1801 << Name << D.getCXXScopeSpec().getRange(); 1802 NewVD->setInvalidDecl(); 1803 } 1804 1805 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1806 1807 // If this is a locally-scoped extern C variable, update the map of 1808 // such variables. 1809 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1810 !NewVD->isInvalidDecl()) 1811 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1812 1813 return NewVD; 1814} 1815 1816/// \brief Perform semantic checking on a newly-created variable 1817/// declaration. 1818/// 1819/// This routine performs all of the type-checking required for a 1820/// variable declaration once it has been built. It is used both to 1821/// check variables after they have been parsed and their declarators 1822/// have been translated into a declaration, and to check variables 1823/// that have been instantiated from a template. 1824/// 1825/// Sets NewVD->isInvalidDecl() if an error was encountered. 1826void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1827 bool &Redeclaration) { 1828 // If the decl is already known invalid, don't check it. 1829 if (NewVD->isInvalidDecl()) 1830 return; 1831 1832 QualType T = NewVD->getType(); 1833 1834 if (T->isObjCInterfaceType()) { 1835 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1836 return NewVD->setInvalidDecl(); 1837 } 1838 1839 // The variable can not have an abstract class type. 1840 if (RequireNonAbstractType(NewVD->getLocation(), T, 1841 diag::err_abstract_type_in_decl, 1842 AbstractVariableType)) 1843 return NewVD->setInvalidDecl(); 1844 1845 // Emit an error if an address space was applied to decl with local storage. 1846 // This includes arrays of objects with address space qualifiers, but not 1847 // automatic variables that point to other address spaces. 1848 // ISO/IEC TR 18037 S5.1.2 1849 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1850 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1851 return NewVD->setInvalidDecl(); 1852 } 1853 1854 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1855 && !NewVD->hasAttr<BlocksAttr>()) 1856 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1857 1858 bool isVM = T->isVariablyModifiedType(); 1859 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1860 CurFunctionNeedsScopeChecking = true; 1861 1862 if ((isVM && NewVD->hasLinkage()) || 1863 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1864 bool SizeIsNegative; 1865 QualType FixedTy = 1866 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1867 1868 if (FixedTy.isNull() && T->isVariableArrayType()) { 1869 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1870 // FIXME: This won't give the correct result for 1871 // int a[10][n]; 1872 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1873 1874 if (NewVD->isFileVarDecl()) 1875 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1876 << SizeRange; 1877 else if (NewVD->getStorageClass() == VarDecl::Static) 1878 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1879 << SizeRange; 1880 else 1881 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1882 << SizeRange; 1883 return NewVD->setInvalidDecl(); 1884 } 1885 1886 if (FixedTy.isNull()) { 1887 if (NewVD->isFileVarDecl()) 1888 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1889 else 1890 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1891 return NewVD->setInvalidDecl(); 1892 } 1893 1894 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1895 NewVD->setType(FixedTy); 1896 } 1897 1898 if (!PrevDecl && NewVD->isExternC(Context)) { 1899 // Since we did not find anything by this name and we're declaring 1900 // an extern "C" variable, look for a non-visible extern "C" 1901 // declaration with the same name. 1902 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1903 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1904 if (Pos != LocallyScopedExternalDecls.end()) 1905 PrevDecl = Pos->second; 1906 } 1907 1908 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1909 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1910 << T; 1911 return NewVD->setInvalidDecl(); 1912 } 1913 1914 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 1915 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 1916 return NewVD->setInvalidDecl(); 1917 } 1918 1919 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 1920 Diag(NewVD->getLocation(), diag::err_block_on_vm); 1921 return NewVD->setInvalidDecl(); 1922 } 1923 1924 if (PrevDecl) { 1925 Redeclaration = true; 1926 MergeVarDecl(NewVD, PrevDecl); 1927 } 1928} 1929 1930NamedDecl* 1931Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1932 QualType R, NamedDecl* PrevDecl, 1933 bool IsFunctionDefinition, bool &Redeclaration) { 1934 assert(R.getTypePtr()->isFunctionType()); 1935 1936 DeclarationName Name = GetNameForDeclarator(D); 1937 FunctionDecl::StorageClass SC = FunctionDecl::None; 1938 switch (D.getDeclSpec().getStorageClassSpec()) { 1939 default: assert(0 && "Unknown storage class!"); 1940 case DeclSpec::SCS_auto: 1941 case DeclSpec::SCS_register: 1942 case DeclSpec::SCS_mutable: 1943 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1944 diag::err_typecheck_sclass_func); 1945 D.setInvalidType(); 1946 break; 1947 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1948 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1949 case DeclSpec::SCS_static: { 1950 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1951 // C99 6.7.1p5: 1952 // The declaration of an identifier for a function that has 1953 // block scope shall have no explicit storage-class specifier 1954 // other than extern 1955 // See also (C++ [dcl.stc]p4). 1956 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1957 diag::err_static_block_func); 1958 SC = FunctionDecl::None; 1959 } else 1960 SC = FunctionDecl::Static; 1961 break; 1962 } 1963 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1964 } 1965 1966 if (D.getDeclSpec().isThreadSpecified()) 1967 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1968 1969 bool isInline = D.getDeclSpec().isInlineSpecified(); 1970 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1971 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1972 1973 // Check that the return type is not an abstract class type. 1974 // For record types, this is done by the AbstractClassUsageDiagnoser once 1975 // the class has been completely parsed. 1976 if (!DC->isRecord() && 1977 RequireNonAbstractType(D.getIdentifierLoc(), 1978 R->getAsFunctionType()->getResultType(), 1979 diag::err_abstract_type_in_decl, 1980 AbstractReturnType)) 1981 D.setInvalidType(); 1982 1983 // Do not allow returning a objc interface by-value. 1984 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1985 Diag(D.getIdentifierLoc(), 1986 diag::err_object_cannot_be_passed_returned_by_value) << 0 1987 << R->getAsFunctionType()->getResultType(); 1988 D.setInvalidType(); 1989 } 1990 1991 bool isVirtualOkay = false; 1992 FunctionDecl *NewFD; 1993 if (D.getKind() == Declarator::DK_Constructor) { 1994 // This is a C++ constructor declaration. 1995 assert(DC->isRecord() && 1996 "Constructors can only be declared in a member context"); 1997 1998 R = CheckConstructorDeclarator(D, R, SC); 1999 2000 // Create the new declaration 2001 NewFD = CXXConstructorDecl::Create(Context, 2002 cast<CXXRecordDecl>(DC), 2003 D.getIdentifierLoc(), Name, R, 2004 isExplicit, isInline, 2005 /*isImplicitlyDeclared=*/false); 2006 } else if (D.getKind() == Declarator::DK_Destructor) { 2007 // This is a C++ destructor declaration. 2008 if (DC->isRecord()) { 2009 R = CheckDestructorDeclarator(D, SC); 2010 2011 NewFD = CXXDestructorDecl::Create(Context, 2012 cast<CXXRecordDecl>(DC), 2013 D.getIdentifierLoc(), Name, R, 2014 isInline, 2015 /*isImplicitlyDeclared=*/false); 2016 2017 isVirtualOkay = true; 2018 } else { 2019 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2020 2021 // Create a FunctionDecl to satisfy the function definition parsing 2022 // code path. 2023 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2024 Name, R, SC, isInline, 2025 /*hasPrototype=*/true, 2026 // FIXME: Move to DeclGroup... 2027 D.getDeclSpec().getSourceRange().getBegin()); 2028 D.setInvalidType(); 2029 } 2030 } else if (D.getKind() == Declarator::DK_Conversion) { 2031 if (!DC->isRecord()) { 2032 Diag(D.getIdentifierLoc(), 2033 diag::err_conv_function_not_member); 2034 return 0; 2035 } 2036 2037 CheckConversionDeclarator(D, R, SC); 2038 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2039 D.getIdentifierLoc(), Name, R, 2040 isInline, isExplicit); 2041 2042 isVirtualOkay = true; 2043 } else if (DC->isRecord()) { 2044 // If the of the function is the same as the name of the record, then this 2045 // must be an invalid constructor that has a return type. 2046 // (The parser checks for a return type and makes the declarator a 2047 // constructor if it has no return type). 2048 // must have an invalid constructor that has a return type 2049 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2050 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2051 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2052 << SourceRange(D.getIdentifierLoc()); 2053 return 0; 2054 } 2055 2056 // This is a C++ method declaration. 2057 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2058 D.getIdentifierLoc(), Name, R, 2059 (SC == FunctionDecl::Static), isInline); 2060 2061 isVirtualOkay = (SC != FunctionDecl::Static); 2062 } else { 2063 // Determine whether the function was written with a 2064 // prototype. This true when: 2065 // - we're in C++ (where every function has a prototype), 2066 // - there is a prototype in the declarator, or 2067 // - the type R of the function is some kind of typedef or other reference 2068 // to a type name (which eventually refers to a function type). 2069 bool HasPrototype = 2070 getLangOptions().CPlusPlus || 2071 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2072 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2073 2074 NewFD = FunctionDecl::Create(Context, DC, 2075 D.getIdentifierLoc(), 2076 Name, R, SC, isInline, HasPrototype, 2077 // FIXME: Move to DeclGroup... 2078 D.getDeclSpec().getSourceRange().getBegin()); 2079 } 2080 2081 if (D.isInvalidType()) 2082 NewFD->setInvalidDecl(); 2083 2084 // Set the lexical context. If the declarator has a C++ 2085 // scope specifier, the lexical context will be different 2086 // from the semantic context. 2087 NewFD->setLexicalDeclContext(CurContext); 2088 2089 // C++ [dcl.fct.spec]p5: 2090 // The virtual specifier shall only be used in declarations of 2091 // nonstatic class member functions that appear within a 2092 // member-specification of a class declaration; see 10.3. 2093 // 2094 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2095 // function is also virtual if it overrides an already virtual 2096 // function. This is important to do here because it's part of the 2097 // declaration. 2098 if (isVirtual && !NewFD->isInvalidDecl()) { 2099 if (!isVirtualOkay) { 2100 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2101 diag::err_virtual_non_function); 2102 } else if (!CurContext->isRecord()) { 2103 // 'virtual' was specified outside of the class. 2104 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2105 << CodeModificationHint::CreateRemoval( 2106 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2107 } else { 2108 // Okay: Add virtual to the method. 2109 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2110 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2111 CurClass->setAggregate(false); 2112 CurClass->setPOD(false); 2113 CurClass->setPolymorphic(true); 2114 CurClass->setHasTrivialConstructor(false); 2115 } 2116 } 2117 2118 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2119 !CurContext->isRecord()) { 2120 // C++ [class.static]p1: 2121 // A data or function member of a class may be declared static 2122 // in a class definition, in which case it is a static member of 2123 // the class. 2124 2125 // Complain about the 'static' specifier if it's on an out-of-line 2126 // member function definition. 2127 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2128 diag::err_static_out_of_line) 2129 << CodeModificationHint::CreateRemoval( 2130 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2131 } 2132 2133 // Handle GNU asm-label extension (encoded as an attribute). 2134 if (Expr *E = (Expr*) D.getAsmLabel()) { 2135 // The parser guarantees this is a string. 2136 StringLiteral *SE = cast<StringLiteral>(E); 2137 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2138 SE->getByteLength()))); 2139 } 2140 2141 // Copy the parameter declarations from the declarator D to the function 2142 // declaration NewFD, if they are available. First scavenge them into Params. 2143 llvm::SmallVector<ParmVarDecl*, 16> Params; 2144 if (D.getNumTypeObjects() > 0) { 2145 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2146 2147 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2148 // function that takes no arguments, not a function that takes a 2149 // single void argument. 2150 // We let through "const void" here because Sema::GetTypeForDeclarator 2151 // already checks for that case. 2152 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2153 FTI.ArgInfo[0].Param && 2154 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2155 // Empty arg list, don't push any params. 2156 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2157 2158 // In C++, the empty parameter-type-list must be spelled "void"; a 2159 // typedef of void is not permitted. 2160 if (getLangOptions().CPlusPlus && 2161 Param->getType().getUnqualifiedType() != Context.VoidTy) 2162 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2163 // FIXME: Leaks decl? 2164 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2165 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2166 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2167 } 2168 2169 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2170 // When we're declaring a function with a typedef, typeof, etc as in the 2171 // following example, we'll need to synthesize (unnamed) 2172 // parameters for use in the declaration. 2173 // 2174 // @code 2175 // typedef void fn(int); 2176 // fn f; 2177 // @endcode 2178 2179 // Synthesize a parameter for each argument type. 2180 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2181 AE = FT->arg_type_end(); AI != AE; ++AI) { 2182 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2183 SourceLocation(), 0, 2184 *AI, VarDecl::None, 0); 2185 Param->setImplicit(); 2186 Params.push_back(Param); 2187 } 2188 } else { 2189 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2190 "Should not need args for typedef of non-prototype fn"); 2191 } 2192 // Finally, we know we have the right number of parameters, install them. 2193 NewFD->setParams(Context, &Params[0], Params.size()); 2194 2195 2196 2197 // If name lookup finds a previous declaration that is not in the 2198 // same scope as the new declaration, this may still be an 2199 // acceptable redeclaration. 2200 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2201 !(NewFD->hasLinkage() && 2202 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2203 PrevDecl = 0; 2204 2205 // Perform semantic checking on the function declaration. 2206 bool OverloadableAttrRequired = false; // FIXME: HACK! 2207 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2208 /*FIXME:*/OverloadableAttrRequired); 2209 2210 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2211 // An out-of-line member function declaration must also be a 2212 // definition (C++ [dcl.meaning]p1). 2213 if (!IsFunctionDefinition) { 2214 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2215 << D.getCXXScopeSpec().getRange(); 2216 NewFD->setInvalidDecl(); 2217 } else if (!Redeclaration) { 2218 // The user tried to provide an out-of-line definition for a 2219 // function that is a member of a class or namespace, but there 2220 // was no such member function declared (C++ [class.mfct]p2, 2221 // C++ [namespace.memdef]p2). For example: 2222 // 2223 // class X { 2224 // void f() const; 2225 // }; 2226 // 2227 // void X::f() { } // ill-formed 2228 // 2229 // Complain about this problem, and attempt to suggest close 2230 // matches (e.g., those that differ only in cv-qualifiers and 2231 // whether the parameter types are references). 2232 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2233 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2234 NewFD->setInvalidDecl(); 2235 2236 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2237 true); 2238 assert(!Prev.isAmbiguous() && 2239 "Cannot have an ambiguity in previous-declaration lookup"); 2240 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2241 Func != FuncEnd; ++Func) { 2242 if (isa<FunctionDecl>(*Func) && 2243 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2244 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2245 } 2246 2247 PrevDecl = 0; 2248 } 2249 } 2250 2251 // Handle attributes. We need to have merged decls when handling attributes 2252 // (for example to check for conflicts, etc). 2253 // FIXME: This needs to happen before we merge declarations. Then, 2254 // let attribute merging cope with attribute conflicts. 2255 ProcessDeclAttributes(NewFD, D); 2256 AddKnownFunctionAttributes(NewFD); 2257 2258 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2259 // If a function name is overloadable in C, then every function 2260 // with that name must be marked "overloadable". 2261 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2262 << Redeclaration << NewFD; 2263 if (PrevDecl) 2264 Diag(PrevDecl->getLocation(), 2265 diag::note_attribute_overloadable_prev_overload); 2266 NewFD->addAttr(::new (Context) OverloadableAttr()); 2267 } 2268 2269 // If this is a locally-scoped extern C function, update the 2270 // map of such names. 2271 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2272 && !NewFD->isInvalidDecl()) 2273 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2274 2275 return NewFD; 2276} 2277 2278/// \brief Perform semantic checking of a new function declaration. 2279/// 2280/// Performs semantic analysis of the new function declaration 2281/// NewFD. This routine performs all semantic checking that does not 2282/// require the actual declarator involved in the declaration, and is 2283/// used both for the declaration of functions as they are parsed 2284/// (called via ActOnDeclarator) and for the declaration of functions 2285/// that have been instantiated via C++ template instantiation (called 2286/// via InstantiateDecl). 2287/// 2288/// This sets NewFD->isInvalidDecl() to true if there was an error. 2289void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2290 bool &Redeclaration, 2291 bool &OverloadableAttrRequired) { 2292 // If NewFD is already known erroneous, don't do any of this checking. 2293 if (NewFD->isInvalidDecl()) 2294 return; 2295 2296 // Semantic checking for this function declaration (in isolation). 2297 if (getLangOptions().CPlusPlus) { 2298 // C++-specific checks. 2299 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2300 CheckConstructor(Constructor); 2301 } else if (isa<CXXDestructorDecl>(NewFD)) { 2302 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2303 Record->setUserDeclaredDestructor(true); 2304 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2305 // user-defined destructor. 2306 Record->setPOD(false); 2307 2308 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2309 // declared destructor. 2310 Record->setHasTrivialDestructor(false); 2311 } else if (CXXConversionDecl *Conversion 2312 = dyn_cast<CXXConversionDecl>(NewFD)) 2313 ActOnConversionDeclarator(Conversion); 2314 2315 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2316 if (NewFD->isOverloadedOperator() && 2317 CheckOverloadedOperatorDeclaration(NewFD)) 2318 return NewFD->setInvalidDecl(); 2319 } 2320 2321 // C99 6.7.4p6: 2322 // [... ] For a function with external linkage, the following 2323 // restrictions apply: [...] If all of the file scope declarations 2324 // for a function in a translation unit include the inline 2325 // function specifier without extern, then the definition in that 2326 // translation unit is an inline definition. An inline definition 2327 // does not provide an external definition for the function, and 2328 // does not forbid an external definition in another translation 2329 // unit. 2330 // 2331 // Here we determine whether this function, in isolation, would be a 2332 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2333 // previous declarations. 2334 if (NewFD->isInline() && getLangOptions().C99 && 2335 NewFD->getStorageClass() == FunctionDecl::None && 2336 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2337 NewFD->setC99InlineDefinition(true); 2338 2339 // Check for a previous declaration of this name. 2340 if (!PrevDecl && NewFD->isExternC(Context)) { 2341 // Since we did not find anything by this name and we're declaring 2342 // an extern "C" function, look for a non-visible extern "C" 2343 // declaration with the same name. 2344 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2345 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2346 if (Pos != LocallyScopedExternalDecls.end()) 2347 PrevDecl = Pos->second; 2348 } 2349 2350 // Merge or overload the declaration with an existing declaration of 2351 // the same name, if appropriate. 2352 if (PrevDecl) { 2353 // Determine whether NewFD is an overload of PrevDecl or 2354 // a declaration that requires merging. If it's an overload, 2355 // there's no more work to do here; we'll just add the new 2356 // function to the scope. 2357 OverloadedFunctionDecl::function_iterator MatchedDecl; 2358 2359 if (!getLangOptions().CPlusPlus && 2360 AllowOverloadingOfFunction(PrevDecl, Context)) { 2361 OverloadableAttrRequired = true; 2362 2363 // Functions marked "overloadable" must have a prototype (that 2364 // we can't get through declaration merging). 2365 if (!NewFD->getType()->getAsFunctionProtoType()) { 2366 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2367 << NewFD; 2368 Redeclaration = true; 2369 2370 // Turn this into a variadic function with no parameters. 2371 QualType R = Context.getFunctionType( 2372 NewFD->getType()->getAsFunctionType()->getResultType(), 2373 0, 0, true, 0); 2374 NewFD->setType(R); 2375 return NewFD->setInvalidDecl(); 2376 } 2377 } 2378 2379 if (PrevDecl && 2380 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2381 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2382 Redeclaration = true; 2383 Decl *OldDecl = PrevDecl; 2384 2385 // If PrevDecl was an overloaded function, extract the 2386 // FunctionDecl that matched. 2387 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2388 OldDecl = *MatchedDecl; 2389 2390 // NewFD and OldDecl represent declarations that need to be 2391 // merged. 2392 if (MergeFunctionDecl(NewFD, OldDecl)) 2393 return NewFD->setInvalidDecl(); 2394 2395 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2396 } 2397 } 2398 2399 // In C++, check default arguments now that we have merged decls. Unless 2400 // the lexical context is the class, because in this case this is done 2401 // during delayed parsing anyway. 2402 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2403 CheckCXXDefaultArguments(NewFD); 2404} 2405 2406bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2407 // FIXME: Need strict checking. In C89, we need to check for 2408 // any assignment, increment, decrement, function-calls, or 2409 // commas outside of a sizeof. In C99, it's the same list, 2410 // except that the aforementioned are allowed in unevaluated 2411 // expressions. Everything else falls under the 2412 // "may accept other forms of constant expressions" exception. 2413 // (We never end up here for C++, so the constant expression 2414 // rules there don't matter.) 2415 if (Init->isConstantInitializer(Context)) 2416 return false; 2417 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2418 << Init->getSourceRange(); 2419 return true; 2420} 2421 2422void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2423 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2424} 2425 2426/// AddInitializerToDecl - Adds the initializer Init to the 2427/// declaration dcl. If DirectInit is true, this is C++ direct 2428/// initialization rather than copy initialization. 2429void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2430 Decl *RealDecl = dcl.getAs<Decl>(); 2431 // If there is no declaration, there was an error parsing it. Just ignore 2432 // the initializer. 2433 if (RealDecl == 0) 2434 return; 2435 2436 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2437 // With declarators parsed the way they are, the parser cannot 2438 // distinguish between a normal initializer and a pure-specifier. 2439 // Thus this grotesque test. 2440 IntegerLiteral *IL; 2441 Expr *Init = static_cast<Expr *>(init.get()); 2442 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2443 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2444 if (Method->isVirtual()) { 2445 Method->setPure(); 2446 2447 // A class is abstract if at least one function is pure virtual. 2448 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2449 } else if (!Method->isInvalidDecl()) { 2450 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2451 << Method->getDeclName() << Init->getSourceRange(); 2452 Method->setInvalidDecl(); 2453 } 2454 } else { 2455 Diag(Method->getLocation(), diag::err_member_function_initialization) 2456 << Method->getDeclName() << Init->getSourceRange(); 2457 Method->setInvalidDecl(); 2458 } 2459 return; 2460 } 2461 2462 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2463 if (!VDecl) { 2464 if (getLangOptions().CPlusPlus && 2465 RealDecl->getLexicalDeclContext()->isRecord() && 2466 isa<NamedDecl>(RealDecl)) 2467 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2468 << cast<NamedDecl>(RealDecl)->getDeclName(); 2469 else 2470 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2471 RealDecl->setInvalidDecl(); 2472 return; 2473 } 2474 2475 if (!VDecl->getType()->isArrayType() && 2476 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2477 diag::err_typecheck_decl_incomplete_type)) { 2478 RealDecl->setInvalidDecl(); 2479 return; 2480 } 2481 2482 const VarDecl *Def = 0; 2483 if (VDecl->getDefinition(Def)) { 2484 Diag(VDecl->getLocation(), diag::err_redefinition) 2485 << VDecl->getDeclName(); 2486 Diag(Def->getLocation(), diag::note_previous_definition); 2487 VDecl->setInvalidDecl(); 2488 return; 2489 } 2490 2491 // Take ownership of the expression, now that we're sure we have somewhere 2492 // to put it. 2493 Expr *Init = init.takeAs<Expr>(); 2494 assert(Init && "missing initializer"); 2495 2496 // Get the decls type and save a reference for later, since 2497 // CheckInitializerTypes may change it. 2498 QualType DclT = VDecl->getType(), SavT = DclT; 2499 if (VDecl->isBlockVarDecl()) { 2500 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2501 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2502 VDecl->setInvalidDecl(); 2503 } else if (!VDecl->isInvalidDecl()) { 2504 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2505 VDecl->getDeclName(), DirectInit)) 2506 VDecl->setInvalidDecl(); 2507 2508 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2509 // Don't check invalid declarations to avoid emitting useless diagnostics. 2510 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2511 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2512 CheckForConstantInitializer(Init, DclT); 2513 } 2514 } 2515 } else if (VDecl->isStaticDataMember() && 2516 VDecl->getLexicalDeclContext()->isRecord()) { 2517 // This is an in-class initialization for a static data member, e.g., 2518 // 2519 // struct S { 2520 // static const int value = 17; 2521 // }; 2522 2523 // Attach the initializer 2524 VDecl->setInit(Init); 2525 2526 // C++ [class.mem]p4: 2527 // A member-declarator can contain a constant-initializer only 2528 // if it declares a static member (9.4) of const integral or 2529 // const enumeration type, see 9.4.2. 2530 QualType T = VDecl->getType(); 2531 if (!T->isDependentType() && 2532 (!Context.getCanonicalType(T).isConstQualified() || 2533 !T->isIntegralType())) { 2534 Diag(VDecl->getLocation(), diag::err_member_initialization) 2535 << VDecl->getDeclName() << Init->getSourceRange(); 2536 VDecl->setInvalidDecl(); 2537 } else { 2538 // C++ [class.static.data]p4: 2539 // If a static data member is of const integral or const 2540 // enumeration type, its declaration in the class definition 2541 // can specify a constant-initializer which shall be an 2542 // integral constant expression (5.19). 2543 if (!Init->isTypeDependent() && 2544 !Init->getType()->isIntegralType()) { 2545 // We have a non-dependent, non-integral or enumeration type. 2546 Diag(Init->getSourceRange().getBegin(), 2547 diag::err_in_class_initializer_non_integral_type) 2548 << Init->getType() << Init->getSourceRange(); 2549 VDecl->setInvalidDecl(); 2550 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2551 // Check whether the expression is a constant expression. 2552 llvm::APSInt Value; 2553 SourceLocation Loc; 2554 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2555 Diag(Loc, diag::err_in_class_initializer_non_constant) 2556 << Init->getSourceRange(); 2557 VDecl->setInvalidDecl(); 2558 } else if (!VDecl->getType()->isDependentType()) 2559 ImpCastExprToType(Init, VDecl->getType()); 2560 } 2561 } 2562 } else if (VDecl->isFileVarDecl()) { 2563 if (VDecl->getStorageClass() == VarDecl::Extern) 2564 Diag(VDecl->getLocation(), diag::warn_extern_init); 2565 if (!VDecl->isInvalidDecl()) 2566 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2567 VDecl->getDeclName(), DirectInit)) 2568 VDecl->setInvalidDecl(); 2569 2570 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2571 // Don't check invalid declarations to avoid emitting useless diagnostics. 2572 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2573 // C99 6.7.8p4. All file scoped initializers need to be constant. 2574 CheckForConstantInitializer(Init, DclT); 2575 } 2576 } 2577 // If the type changed, it means we had an incomplete type that was 2578 // completed by the initializer. For example: 2579 // int ary[] = { 1, 3, 5 }; 2580 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2581 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2582 VDecl->setType(DclT); 2583 Init->setType(DclT); 2584 } 2585 2586 // Attach the initializer to the decl. 2587 VDecl->setInit(Init); 2588 2589 // If the previous declaration of VDecl was a tentative definition, 2590 // remove it from the set of tentative definitions. 2591 if (VDecl->getPreviousDeclaration() && 2592 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2593 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2594 = TentativeDefinitions.find(VDecl->getDeclName()); 2595 assert(Pos != TentativeDefinitions.end() && 2596 "Unrecorded tentative definition?"); 2597 TentativeDefinitions.erase(Pos); 2598 } 2599 2600 return; 2601} 2602 2603void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2604 Decl *RealDecl = dcl.getAs<Decl>(); 2605 2606 // If there is no declaration, there was an error parsing it. Just ignore it. 2607 if (RealDecl == 0) 2608 return; 2609 2610 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2611 QualType Type = Var->getType(); 2612 2613 // Record tentative definitions. 2614 if (Var->isTentativeDefinition(Context)) 2615 TentativeDefinitions[Var->getDeclName()] = Var; 2616 2617 // C++ [dcl.init.ref]p3: 2618 // The initializer can be omitted for a reference only in a 2619 // parameter declaration (8.3.5), in the declaration of a 2620 // function return type, in the declaration of a class member 2621 // within its class declaration (9.2), and where the extern 2622 // specifier is explicitly used. 2623 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2624 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2625 << Var->getDeclName() 2626 << SourceRange(Var->getLocation(), Var->getLocation()); 2627 Var->setInvalidDecl(); 2628 return; 2629 } 2630 2631 // C++ [dcl.init]p9: 2632 // 2633 // If no initializer is specified for an object, and the object 2634 // is of (possibly cv-qualified) non-POD class type (or array 2635 // thereof), the object shall be default-initialized; if the 2636 // object is of const-qualified type, the underlying class type 2637 // shall have a user-declared default constructor. 2638 if (getLangOptions().CPlusPlus) { 2639 QualType InitType = Type; 2640 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2641 InitType = Array->getElementType(); 2642 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2643 CXXRecordDecl *RD = 2644 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2645 CXXConstructorDecl *Constructor = 0; 2646 if (!RequireCompleteType(Var->getLocation(), InitType, 2647 diag::err_invalid_incomplete_type_use)) 2648 Constructor 2649 = PerformInitializationByConstructor(InitType, 0, 0, 2650 Var->getLocation(), 2651 SourceRange(Var->getLocation(), 2652 Var->getLocation()), 2653 Var->getDeclName(), 2654 IK_Default); 2655 if (!Constructor) 2656 Var->setInvalidDecl(); 2657 else if (!RD->hasTrivialConstructor()) 2658 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2659 } 2660 } 2661 2662#if 0 2663 // FIXME: Temporarily disabled because we are not properly parsing 2664 // linkage specifications on declarations, e.g., 2665 // 2666 // extern "C" const CGPoint CGPointerZero; 2667 // 2668 // C++ [dcl.init]p9: 2669 // 2670 // If no initializer is specified for an object, and the 2671 // object is of (possibly cv-qualified) non-POD class type (or 2672 // array thereof), the object shall be default-initialized; if 2673 // the object is of const-qualified type, the underlying class 2674 // type shall have a user-declared default 2675 // constructor. Otherwise, if no initializer is specified for 2676 // an object, the object and its subobjects, if any, have an 2677 // indeterminate initial value; if the object or any of its 2678 // subobjects are of const-qualified type, the program is 2679 // ill-formed. 2680 // 2681 // This isn't technically an error in C, so we don't diagnose it. 2682 // 2683 // FIXME: Actually perform the POD/user-defined default 2684 // constructor check. 2685 if (getLangOptions().CPlusPlus && 2686 Context.getCanonicalType(Type).isConstQualified() && 2687 !Var->hasExternalStorage()) 2688 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2689 << Var->getName() 2690 << SourceRange(Var->getLocation(), Var->getLocation()); 2691#endif 2692 } 2693} 2694 2695Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2696 unsigned NumDecls) { 2697 llvm::SmallVector<Decl*, 8> Decls; 2698 2699 for (unsigned i = 0; i != NumDecls; ++i) 2700 if (Decl *D = Group[i].getAs<Decl>()) 2701 Decls.push_back(D); 2702 2703 // Perform semantic analysis that depends on having fully processed both 2704 // the declarator and initializer. 2705 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2706 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2707 if (!IDecl) 2708 continue; 2709 QualType T = IDecl->getType(); 2710 2711 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2712 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2713 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2714 if (!IDecl->isInvalidDecl() && 2715 RequireCompleteType(IDecl->getLocation(), T, 2716 diag::err_typecheck_decl_incomplete_type)) 2717 IDecl->setInvalidDecl(); 2718 } 2719 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2720 // object that has file scope without an initializer, and without a 2721 // storage-class specifier or with the storage-class specifier "static", 2722 // constitutes a tentative definition. Note: A tentative definition with 2723 // external linkage is valid (C99 6.2.2p5). 2724 if (IDecl->isTentativeDefinition(Context)) { 2725 QualType CheckType = T; 2726 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2727 2728 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2729 if (ArrayT) { 2730 CheckType = ArrayT->getElementType(); 2731 DiagID = diag::err_illegal_decl_array_incomplete_type; 2732 } 2733 2734 if (IDecl->isInvalidDecl()) { 2735 // Do nothing with invalid declarations 2736 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2737 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2738 // C99 6.9.2p3: If the declaration of an identifier for an object is 2739 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2740 // declared type shall not be an incomplete type. 2741 IDecl->setInvalidDecl(); 2742 } 2743 } 2744 } 2745 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2746 &Decls[0], Decls.size())); 2747} 2748 2749 2750/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2751/// to introduce parameters into function prototype scope. 2752Sema::DeclPtrTy 2753Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2754 const DeclSpec &DS = D.getDeclSpec(); 2755 2756 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2757 VarDecl::StorageClass StorageClass = VarDecl::None; 2758 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2759 StorageClass = VarDecl::Register; 2760 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2761 Diag(DS.getStorageClassSpecLoc(), 2762 diag::err_invalid_storage_class_in_func_decl); 2763 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2764 } 2765 2766 if (D.getDeclSpec().isThreadSpecified()) 2767 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2768 2769 DiagnoseFunctionSpecifiers(D); 2770 2771 // Check that there are no default arguments inside the type of this 2772 // parameter (C++ only). 2773 if (getLangOptions().CPlusPlus) 2774 CheckExtraCXXDefaultArguments(D); 2775 2776 QualType parmDeclType = GetTypeForDeclarator(D, S); 2777 2778 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2779 // Can this happen for params? We already checked that they don't conflict 2780 // among each other. Here they can only shadow globals, which is ok. 2781 IdentifierInfo *II = D.getIdentifier(); 2782 if (II) { 2783 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2784 if (PrevDecl->isTemplateParameter()) { 2785 // Maybe we will complain about the shadowed template parameter. 2786 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2787 // Just pretend that we didn't see the previous declaration. 2788 PrevDecl = 0; 2789 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2790 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2791 2792 // Recover by removing the name 2793 II = 0; 2794 D.SetIdentifier(0, D.getIdentifierLoc()); 2795 } 2796 } 2797 } 2798 2799 // Parameters can not be abstract class types. 2800 // For record types, this is done by the AbstractClassUsageDiagnoser once 2801 // the class has been completely parsed. 2802 if (!CurContext->isRecord() && 2803 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2804 diag::err_abstract_type_in_decl, 2805 AbstractParamType)) 2806 D.setInvalidType(true); 2807 2808 QualType T = adjustParameterType(parmDeclType); 2809 2810 ParmVarDecl *New; 2811 if (T == parmDeclType) // parameter type did not need adjustment 2812 New = ParmVarDecl::Create(Context, CurContext, 2813 D.getIdentifierLoc(), II, 2814 parmDeclType, StorageClass, 2815 0); 2816 else // keep track of both the adjusted and unadjusted types 2817 New = OriginalParmVarDecl::Create(Context, CurContext, 2818 D.getIdentifierLoc(), II, T, 2819 parmDeclType, StorageClass, 0); 2820 2821 if (D.isInvalidType()) 2822 New->setInvalidDecl(); 2823 2824 // Parameter declarators cannot be interface types. All ObjC objects are 2825 // passed by reference. 2826 if (T->isObjCInterfaceType()) { 2827 Diag(D.getIdentifierLoc(), 2828 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2829 New->setInvalidDecl(); 2830 } 2831 2832 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2833 if (D.getCXXScopeSpec().isSet()) { 2834 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2835 << D.getCXXScopeSpec().getRange(); 2836 New->setInvalidDecl(); 2837 } 2838 2839 // Add the parameter declaration into this scope. 2840 S->AddDecl(DeclPtrTy::make(New)); 2841 if (II) 2842 IdResolver.AddDecl(New); 2843 2844 ProcessDeclAttributes(New, D); 2845 2846 if (New->hasAttr<BlocksAttr>()) { 2847 Diag(New->getLocation(), diag::err_block_on_nonlocal); 2848 } 2849 return DeclPtrTy::make(New); 2850} 2851 2852void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2853 SourceLocation LocAfterDecls) { 2854 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2855 "Not a function declarator!"); 2856 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2857 2858 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2859 // for a K&R function. 2860 if (!FTI.hasPrototype) { 2861 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2862 --i; 2863 if (FTI.ArgInfo[i].Param == 0) { 2864 std::string Code = " int "; 2865 Code += FTI.ArgInfo[i].Ident->getName(); 2866 Code += ";\n"; 2867 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2868 << FTI.ArgInfo[i].Ident 2869 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2870 2871 // Implicitly declare the argument as type 'int' for lack of a better 2872 // type. 2873 DeclSpec DS; 2874 const char* PrevSpec; // unused 2875 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2876 PrevSpec); 2877 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2878 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2879 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2880 } 2881 } 2882 } 2883} 2884 2885Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2886 Declarator &D) { 2887 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2888 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2889 "Not a function declarator!"); 2890 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2891 2892 if (FTI.hasPrototype) { 2893 // FIXME: Diagnose arguments without names in C. 2894 } 2895 2896 Scope *ParentScope = FnBodyScope->getParent(); 2897 2898 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2899 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2900} 2901 2902Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2903 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2904 2905 CurFunctionNeedsScopeChecking = false; 2906 2907 // See if this is a redefinition. 2908 const FunctionDecl *Definition; 2909 if (FD->getBody(Context, Definition)) { 2910 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2911 Diag(Definition->getLocation(), diag::note_previous_definition); 2912 } 2913 2914 // Builtin functions cannot be defined. 2915 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2916 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2917 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2918 FD->setInvalidDecl(); 2919 } 2920 } 2921 2922 // The return type of a function definition must be complete 2923 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2924 QualType ResultType = FD->getResultType(); 2925 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2926 !FD->isInvalidDecl() && 2927 RequireCompleteType(FD->getLocation(), ResultType, 2928 diag::err_func_def_incomplete_result)) 2929 FD->setInvalidDecl(); 2930 2931 // GNU warning -Wmissing-prototypes: 2932 // Warn if a global function is defined without a previous 2933 // prototype declaration. This warning is issued even if the 2934 // definition itself provides a prototype. The aim is to detect 2935 // global functions that fail to be declared in header files. 2936 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2937 !FD->isMain()) { 2938 bool MissingPrototype = true; 2939 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2940 Prev; Prev = Prev->getPreviousDeclaration()) { 2941 // Ignore any declarations that occur in function or method 2942 // scope, because they aren't visible from the header. 2943 if (Prev->getDeclContext()->isFunctionOrMethod()) 2944 continue; 2945 2946 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2947 break; 2948 } 2949 2950 if (MissingPrototype) 2951 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2952 } 2953 2954 PushDeclContext(FnBodyScope, FD); 2955 2956 // Check the validity of our function parameters 2957 CheckParmsForFunctionDef(FD); 2958 2959 // Introduce our parameters into the function scope 2960 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2961 ParmVarDecl *Param = FD->getParamDecl(p); 2962 Param->setOwningFunction(FD); 2963 2964 // If this has an identifier, add it to the scope stack. 2965 if (Param->getIdentifier()) 2966 PushOnScopeChains(Param, FnBodyScope); 2967 } 2968 2969 // Checking attributes of current function definition 2970 // dllimport attribute. 2971 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2972 // dllimport attribute cannot be applied to definition. 2973 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2974 Diag(FD->getLocation(), 2975 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2976 << "dllimport"; 2977 FD->setInvalidDecl(); 2978 return DeclPtrTy::make(FD); 2979 } else { 2980 // If a symbol previously declared dllimport is later defined, the 2981 // attribute is ignored in subsequent references, and a warning is 2982 // emitted. 2983 Diag(FD->getLocation(), 2984 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2985 << FD->getNameAsCString() << "dllimport"; 2986 } 2987 } 2988 return DeclPtrTy::make(FD); 2989} 2990 2991 2992Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 2993 Decl *dcl = D.getAs<Decl>(); 2994 Stmt *Body = BodyArg.takeAs<Stmt>(); 2995 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2996 FD->setBody(Body); 2997 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2998 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2999 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3000 MD->setBody(Body); 3001 } else { 3002 Body->Destroy(Context); 3003 return DeclPtrTy(); 3004 } 3005 PopDeclContext(); 3006 // Verify and clean out per-function state. 3007 3008 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3009 3010 // Check goto/label use. 3011 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3012 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3013 LabelStmt *L = I->second; 3014 3015 // Verify that we have no forward references left. If so, there was a goto 3016 // or address of a label taken, but no definition of it. Label fwd 3017 // definitions are indicated with a null substmt. 3018 if (L->getSubStmt() != 0) 3019 continue; 3020 3021 // Emit error. 3022 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3023 3024 // At this point, we have gotos that use the bogus label. Stitch it into 3025 // the function body so that they aren't leaked and that the AST is well 3026 // formed. 3027 if (Body == 0) { 3028 // The whole function wasn't parsed correctly, just delete this. 3029 L->Destroy(Context); 3030 continue; 3031 } 3032 3033 // Otherwise, the body is valid: we want to stitch the label decl into the 3034 // function somewhere so that it is properly owned and so that the goto 3035 // has a valid target. Do this by creating a new compound stmt with the 3036 // label in it. 3037 3038 // Give the label a sub-statement. 3039 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3040 3041 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3042 cast<CXXTryStmt>(Body)->getTryBlock() : 3043 cast<CompoundStmt>(Body); 3044 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3045 Elements.push_back(L); 3046 Compound->setStmts(Context, &Elements[0], Elements.size()); 3047 } 3048 FunctionLabelMap.clear(); 3049 3050 if (!Body) return D; 3051 3052 // Verify that that gotos and switch cases don't jump into scopes illegally. 3053 if (CurFunctionNeedsScopeChecking) 3054 DiagnoseInvalidJumps(Body); 3055 3056 // C++ constructors that have function-try-blocks can't have return statements 3057 // in the handlers of that block. (C++ [except.handle]p14) Verify this. 3058 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3059 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3060 3061 return D; 3062} 3063 3064/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3065/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3066NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3067 IdentifierInfo &II, Scope *S) { 3068 // Before we produce a declaration for an implicitly defined 3069 // function, see whether there was a locally-scoped declaration of 3070 // this name as a function or variable. If so, use that 3071 // (non-visible) declaration, and complain about it. 3072 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3073 = LocallyScopedExternalDecls.find(&II); 3074 if (Pos != LocallyScopedExternalDecls.end()) { 3075 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3076 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3077 return Pos->second; 3078 } 3079 3080 // Extension in C99. Legal in C90, but warn about it. 3081 if (getLangOptions().C99) 3082 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3083 else 3084 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3085 3086 // FIXME: handle stuff like: 3087 // void foo() { extern float X(); } 3088 // void bar() { X(); } <-- implicit decl for X in another scope. 3089 3090 // Set a Declarator for the implicit definition: int foo(); 3091 const char *Dummy; 3092 DeclSpec DS; 3093 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3094 Error = Error; // Silence warning. 3095 assert(!Error && "Error setting up implicit decl!"); 3096 Declarator D(DS, Declarator::BlockContext); 3097 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 3098 0, 0, false, false, 0, 0, Loc, D), 3099 SourceLocation()); 3100 D.SetIdentifier(&II, Loc); 3101 3102 // Insert this function into translation-unit scope. 3103 3104 DeclContext *PrevDC = CurContext; 3105 CurContext = Context.getTranslationUnitDecl(); 3106 3107 FunctionDecl *FD = 3108 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3109 FD->setImplicit(); 3110 3111 CurContext = PrevDC; 3112 3113 AddKnownFunctionAttributes(FD); 3114 3115 return FD; 3116} 3117 3118/// \brief Adds any function attributes that we know a priori based on 3119/// the declaration of this function. 3120/// 3121/// These attributes can apply both to implicitly-declared builtins 3122/// (like __builtin___printf_chk) or to library-declared functions 3123/// like NSLog or printf. 3124void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3125 if (FD->isInvalidDecl()) 3126 return; 3127 3128 // If this is a built-in function, map its builtin attributes to 3129 // actual attributes. 3130 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3131 // Handle printf-formatting attributes. 3132 unsigned FormatIdx; 3133 bool HasVAListArg; 3134 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3135 if (!FD->getAttr<FormatAttr>()) 3136 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3137 FormatIdx + 2)); 3138 } 3139 3140 // Mark const if we don't care about errno and that is the only 3141 // thing preventing the function from being const. This allows 3142 // IRgen to use LLVM intrinsics for such functions. 3143 if (!getLangOptions().MathErrno && 3144 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3145 if (!FD->getAttr<ConstAttr>()) 3146 FD->addAttr(::new (Context) ConstAttr()); 3147 } 3148 } 3149 3150 IdentifierInfo *Name = FD->getIdentifier(); 3151 if (!Name) 3152 return; 3153 if ((!getLangOptions().CPlusPlus && 3154 FD->getDeclContext()->isTranslationUnit()) || 3155 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3156 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3157 LinkageSpecDecl::lang_c)) { 3158 // Okay: this could be a libc/libm/Objective-C function we know 3159 // about. 3160 } else 3161 return; 3162 3163 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3164 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3165 // FIXME: We known better than our headers. 3166 const_cast<FormatAttr *>(Format)->setType("printf"); 3167 } else 3168 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3169 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3170 if (!FD->getAttr<FormatAttr>()) 3171 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3172 } 3173} 3174 3175TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3176 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3177 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3178 3179 // Scope manipulation handled by caller. 3180 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3181 D.getIdentifierLoc(), 3182 D.getIdentifier(), 3183 T); 3184 3185 if (TagType *TT = dyn_cast<TagType>(T)) { 3186 TagDecl *TD = TT->getDecl(); 3187 3188 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3189 // keep track of the TypedefDecl. 3190 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3191 TD->setTypedefForAnonDecl(NewTD); 3192 } 3193 3194 if (D.isInvalidType()) 3195 NewTD->setInvalidDecl(); 3196 return NewTD; 3197} 3198 3199/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3200/// former case, Name will be non-null. In the later case, Name will be null. 3201/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3202/// reference/declaration/definition of a tag. 3203Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3204 SourceLocation KWLoc, const CXXScopeSpec &SS, 3205 IdentifierInfo *Name, SourceLocation NameLoc, 3206 AttributeList *Attr, AccessSpecifier AS) { 3207 // If this is not a definition, it must have a name. 3208 assert((Name != 0 || TK == TK_Definition) && 3209 "Nameless record must be a definition!"); 3210 3211 TagDecl::TagKind Kind; 3212 switch (TagSpec) { 3213 default: assert(0 && "Unknown tag type!"); 3214 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3215 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3216 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3217 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3218 } 3219 3220 DeclContext *SearchDC = CurContext; 3221 DeclContext *DC = CurContext; 3222 NamedDecl *PrevDecl = 0; 3223 3224 bool Invalid = false; 3225 3226 if (Name && SS.isNotEmpty()) { 3227 // We have a nested-name tag ('struct foo::bar'). 3228 3229 // Check for invalid 'foo::'. 3230 if (SS.isInvalid()) { 3231 Name = 0; 3232 goto CreateNewDecl; 3233 } 3234 3235 // FIXME: RequireCompleteDeclContext(SS)? 3236 DC = computeDeclContext(SS); 3237 SearchDC = DC; 3238 // Look-up name inside 'foo::'. 3239 PrevDecl = dyn_cast_or_null<TagDecl>( 3240 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3241 3242 // A tag 'foo::bar' must already exist. 3243 if (PrevDecl == 0) { 3244 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3245 Name = 0; 3246 goto CreateNewDecl; 3247 } 3248 } else if (Name) { 3249 // If this is a named struct, check to see if there was a previous forward 3250 // declaration or definition. 3251 // FIXME: We're looking into outer scopes here, even when we 3252 // shouldn't be. Doing so can result in ambiguities that we 3253 // shouldn't be diagnosing. 3254 LookupResult R = LookupName(S, Name, LookupTagName, 3255 /*RedeclarationOnly=*/(TK != TK_Reference)); 3256 if (R.isAmbiguous()) { 3257 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3258 // FIXME: This is not best way to recover from case like: 3259 // 3260 // struct S s; 3261 // 3262 // causes needless "incomplete type" error later. 3263 Name = 0; 3264 PrevDecl = 0; 3265 Invalid = true; 3266 } 3267 else 3268 PrevDecl = R; 3269 3270 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3271 // FIXME: This makes sure that we ignore the contexts associated 3272 // with C structs, unions, and enums when looking for a matching 3273 // tag declaration or definition. See the similar lookup tweak 3274 // in Sema::LookupName; is there a better way to deal with this? 3275 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3276 SearchDC = SearchDC->getParent(); 3277 } 3278 } 3279 3280 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3281 // Maybe we will complain about the shadowed template parameter. 3282 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3283 // Just pretend that we didn't see the previous declaration. 3284 PrevDecl = 0; 3285 } 3286 3287 if (PrevDecl) { 3288 // Check whether the previous declaration is usable. 3289 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3290 3291 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3292 // If this is a use of a previous tag, or if the tag is already declared 3293 // in the same scope (so that the definition/declaration completes or 3294 // rementions the tag), reuse the decl. 3295 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3296 // Make sure that this wasn't declared as an enum and now used as a 3297 // struct or something similar. 3298 if (PrevTagDecl->getTagKind() != Kind) { 3299 bool SafeToContinue 3300 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3301 Kind != TagDecl::TK_enum); 3302 if (SafeToContinue) 3303 Diag(KWLoc, diag::err_use_with_wrong_tag) 3304 << Name 3305 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3306 PrevTagDecl->getKindName()); 3307 else 3308 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3309 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3310 3311 if (SafeToContinue) 3312 Kind = PrevTagDecl->getTagKind(); 3313 else { 3314 // Recover by making this an anonymous redefinition. 3315 Name = 0; 3316 PrevDecl = 0; 3317 Invalid = true; 3318 } 3319 } 3320 3321 if (!Invalid) { 3322 // If this is a use, just return the declaration we found. 3323 3324 // FIXME: In the future, return a variant or some other clue 3325 // for the consumer of this Decl to know it doesn't own it. 3326 // For our current ASTs this shouldn't be a problem, but will 3327 // need to be changed with DeclGroups. 3328 if (TK == TK_Reference) 3329 return DeclPtrTy::make(PrevDecl); 3330 3331 // Diagnose attempts to redefine a tag. 3332 if (TK == TK_Definition) { 3333 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3334 Diag(NameLoc, diag::err_redefinition) << Name; 3335 Diag(Def->getLocation(), diag::note_previous_definition); 3336 // If this is a redefinition, recover by making this 3337 // struct be anonymous, which will make any later 3338 // references get the previous definition. 3339 Name = 0; 3340 PrevDecl = 0; 3341 Invalid = true; 3342 } else { 3343 // If the type is currently being defined, complain 3344 // about a nested redefinition. 3345 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3346 if (Tag->isBeingDefined()) { 3347 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3348 Diag(PrevTagDecl->getLocation(), 3349 diag::note_previous_definition); 3350 Name = 0; 3351 PrevDecl = 0; 3352 Invalid = true; 3353 } 3354 } 3355 3356 // Okay, this is definition of a previously declared or referenced 3357 // tag PrevDecl. We're going to create a new Decl for it. 3358 } 3359 } 3360 // If we get here we have (another) forward declaration or we 3361 // have a definition. Just create a new decl. 3362 } else { 3363 // If we get here, this is a definition of a new tag type in a nested 3364 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3365 // new decl/type. We set PrevDecl to NULL so that the entities 3366 // have distinct types. 3367 PrevDecl = 0; 3368 } 3369 // If we get here, we're going to create a new Decl. If PrevDecl 3370 // is non-NULL, it's a definition of the tag declared by 3371 // PrevDecl. If it's NULL, we have a new definition. 3372 } else { 3373 // PrevDecl is a namespace, template, or anything else 3374 // that lives in the IDNS_Tag identifier namespace. 3375 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3376 // The tag name clashes with a namespace name, issue an error and 3377 // recover by making this tag be anonymous. 3378 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3379 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3380 Name = 0; 3381 PrevDecl = 0; 3382 Invalid = true; 3383 } else { 3384 // The existing declaration isn't relevant to us; we're in a 3385 // new scope, so clear out the previous declaration. 3386 PrevDecl = 0; 3387 } 3388 } 3389 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3390 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3391 // C.scope.pdecl]p5: 3392 // -- for an elaborated-type-specifier of the form 3393 // 3394 // class-key identifier 3395 // 3396 // if the elaborated-type-specifier is used in the 3397 // decl-specifier-seq or parameter-declaration-clause of a 3398 // function defined in namespace scope, the identifier is 3399 // declared as a class-name in the namespace that contains 3400 // the declaration; otherwise, except as a friend 3401 // declaration, the identifier is declared in the smallest 3402 // non-class, non-function-prototype scope that contains the 3403 // declaration. 3404 // 3405 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3406 // C structs and unions. 3407 // 3408 // GNU C also supports this behavior as part of its incomplete 3409 // enum types extension, while GNU C++ does not. 3410 // 3411 // Find the context where we'll be declaring the tag. 3412 // FIXME: We would like to maintain the current DeclContext as the 3413 // lexical context, 3414 while (SearchDC->isRecord()) 3415 SearchDC = SearchDC->getParent(); 3416 3417 // Find the scope where we'll be declaring the tag. 3418 while (S->isClassScope() || 3419 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3420 ((S->getFlags() & Scope::DeclScope) == 0) || 3421 (S->getEntity() && 3422 ((DeclContext *)S->getEntity())->isTransparentContext())) 3423 S = S->getParent(); 3424 } 3425 3426CreateNewDecl: 3427 3428 // If there is an identifier, use the location of the identifier as the 3429 // location of the decl, otherwise use the location of the struct/union 3430 // keyword. 3431 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3432 3433 // Otherwise, create a new declaration. If there is a previous 3434 // declaration of the same entity, the two will be linked via 3435 // PrevDecl. 3436 TagDecl *New; 3437 3438 if (Kind == TagDecl::TK_enum) { 3439 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3440 // enum X { A, B, C } D; D should chain to X. 3441 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3442 cast_or_null<EnumDecl>(PrevDecl)); 3443 // If this is an undefined enum, warn. 3444 if (TK != TK_Definition && !Invalid) { 3445 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3446 : diag::ext_forward_ref_enum; 3447 Diag(Loc, DK); 3448 } 3449 } else { 3450 // struct/union/class 3451 3452 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3453 // struct X { int A; } D; D should chain to X. 3454 if (getLangOptions().CPlusPlus) 3455 // FIXME: Look for a way to use RecordDecl for simple structs. 3456 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3457 cast_or_null<CXXRecordDecl>(PrevDecl)); 3458 else 3459 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3460 cast_or_null<RecordDecl>(PrevDecl)); 3461 } 3462 3463 if (Kind != TagDecl::TK_enum) { 3464 // Handle #pragma pack: if the #pragma pack stack has non-default 3465 // alignment, make up a packed attribute for this decl. These 3466 // attributes are checked when the ASTContext lays out the 3467 // structure. 3468 // 3469 // It is important for implementing the correct semantics that this 3470 // happen here (in act on tag decl). The #pragma pack stack is 3471 // maintained as a result of parser callbacks which can occur at 3472 // many points during the parsing of a struct declaration (because 3473 // the #pragma tokens are effectively skipped over during the 3474 // parsing of the struct). 3475 if (unsigned Alignment = getPragmaPackAlignment()) 3476 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3477 } 3478 3479 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3480 // C++ [dcl.typedef]p3: 3481 // [...] Similarly, in a given scope, a class or enumeration 3482 // shall not be declared with the same name as a typedef-name 3483 // that is declared in that scope and refers to a type other 3484 // than the class or enumeration itself. 3485 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3486 TypedefDecl *PrevTypedef = 0; 3487 if (Lookup.getKind() == LookupResult::Found) 3488 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3489 3490 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3491 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3492 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3493 Diag(Loc, diag::err_tag_definition_of_typedef) 3494 << Context.getTypeDeclType(New) 3495 << PrevTypedef->getUnderlyingType(); 3496 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3497 Invalid = true; 3498 } 3499 } 3500 3501 if (Invalid) 3502 New->setInvalidDecl(); 3503 3504 if (Attr) 3505 ProcessDeclAttributeList(New, Attr); 3506 3507 // If we're declaring or defining a tag in function prototype scope 3508 // in C, note that this type can only be used within the function. 3509 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3510 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3511 3512 // Set the lexical context. If the tag has a C++ scope specifier, the 3513 // lexical context will be different from the semantic context. 3514 New->setLexicalDeclContext(CurContext); 3515 3516 // Set the access specifier. 3517 SetMemberAccessSpecifier(New, PrevDecl, AS); 3518 3519 if (TK == TK_Definition) 3520 New->startDefinition(); 3521 3522 // If this has an identifier, add it to the scope stack. 3523 if (Name) { 3524 S = getNonFieldDeclScope(S); 3525 PushOnScopeChains(New, S); 3526 } else { 3527 CurContext->addDecl(Context, New); 3528 } 3529 3530 return DeclPtrTy::make(New); 3531} 3532 3533void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3534 AdjustDeclIfTemplate(TagD); 3535 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3536 3537 // Enter the tag context. 3538 PushDeclContext(S, Tag); 3539 3540 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3541 FieldCollector->StartClass(); 3542 3543 if (Record->getIdentifier()) { 3544 // C++ [class]p2: 3545 // [...] The class-name is also inserted into the scope of the 3546 // class itself; this is known as the injected-class-name. For 3547 // purposes of access checking, the injected-class-name is treated 3548 // as if it were a public member name. 3549 CXXRecordDecl *InjectedClassName 3550 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3551 CurContext, Record->getLocation(), 3552 Record->getIdentifier(), Record); 3553 InjectedClassName->setImplicit(); 3554 InjectedClassName->setAccess(AS_public); 3555 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3556 InjectedClassName->setDescribedClassTemplate(Template); 3557 PushOnScopeChains(InjectedClassName, S); 3558 assert(InjectedClassName->isInjectedClassName() && 3559 "Broken injected-class-name"); 3560 } 3561 } 3562} 3563 3564void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3565 AdjustDeclIfTemplate(TagD); 3566 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3567 3568 if (isa<CXXRecordDecl>(Tag)) 3569 FieldCollector->FinishClass(); 3570 3571 // Exit this scope of this tag's definition. 3572 PopDeclContext(); 3573 3574 // Notify the consumer that we've defined a tag. 3575 Consumer.HandleTagDeclDefinition(Tag); 3576} 3577 3578// Note that FieldName may be null for anonymous bitfields. 3579bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3580 QualType FieldTy, const Expr *BitWidth) { 3581 3582 // C99 6.7.2.1p4 - verify the field type. 3583 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3584 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3585 // Handle incomplete types with specific error. 3586 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3587 return true; 3588 if (FieldName) 3589 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3590 << FieldName << FieldTy << BitWidth->getSourceRange(); 3591 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3592 << FieldTy << BitWidth->getSourceRange(); 3593 } 3594 3595 // If the bit-width is type- or value-dependent, don't try to check 3596 // it now. 3597 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3598 return false; 3599 3600 llvm::APSInt Value; 3601 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3602 return true; 3603 3604 // Zero-width bitfield is ok for anonymous field. 3605 if (Value == 0 && FieldName) 3606 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3607 3608 if (Value.isSigned() && Value.isNegative()) { 3609 if (FieldName) 3610 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3611 << FieldName << Value.toString(10); 3612 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3613 << Value.toString(10); 3614 } 3615 3616 if (!FieldTy->isDependentType()) { 3617 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3618 if (Value.getZExtValue() > TypeSize) { 3619 if (FieldName) 3620 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3621 << FieldName << (unsigned)TypeSize; 3622 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3623 << (unsigned)TypeSize; 3624 } 3625 } 3626 3627 return false; 3628} 3629 3630/// ActOnField - Each field of a struct/union/class is passed into this in order 3631/// to create a FieldDecl object for it. 3632Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3633 SourceLocation DeclStart, 3634 Declarator &D, ExprTy *BitfieldWidth) { 3635 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3636 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3637 AS_public); 3638 return DeclPtrTy::make(Res); 3639} 3640 3641/// HandleField - Analyze a field of a C struct or a C++ data member. 3642/// 3643FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3644 SourceLocation DeclStart, 3645 Declarator &D, Expr *BitWidth, 3646 AccessSpecifier AS) { 3647 IdentifierInfo *II = D.getIdentifier(); 3648 SourceLocation Loc = DeclStart; 3649 if (II) Loc = D.getIdentifierLoc(); 3650 3651 QualType T = GetTypeForDeclarator(D, S); 3652 if (getLangOptions().CPlusPlus) 3653 CheckExtraCXXDefaultArguments(D); 3654 3655 DiagnoseFunctionSpecifiers(D); 3656 3657 if (D.getDeclSpec().isThreadSpecified()) 3658 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3659 3660 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3661 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3662 PrevDecl = 0; 3663 3664 FieldDecl *NewFD 3665 = CheckFieldDecl(II, T, Record, Loc, 3666 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3667 BitWidth, AS, PrevDecl, &D); 3668 if (NewFD->isInvalidDecl() && PrevDecl) { 3669 // Don't introduce NewFD into scope; there's already something 3670 // with the same name in the same scope. 3671 } else if (II) { 3672 PushOnScopeChains(NewFD, S); 3673 } else 3674 Record->addDecl(Context, NewFD); 3675 3676 return NewFD; 3677} 3678 3679/// \brief Build a new FieldDecl and check its well-formedness. 3680/// 3681/// This routine builds a new FieldDecl given the fields name, type, 3682/// record, etc. \p PrevDecl should refer to any previous declaration 3683/// with the same name and in the same scope as the field to be 3684/// created. 3685/// 3686/// \returns a new FieldDecl. 3687/// 3688/// \todo The Declarator argument is a hack. It will be removed once 3689FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3690 RecordDecl *Record, SourceLocation Loc, 3691 bool Mutable, Expr *BitWidth, 3692 AccessSpecifier AS, NamedDecl *PrevDecl, 3693 Declarator *D) { 3694 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3695 bool InvalidDecl = false; 3696 if (D) InvalidDecl = D->isInvalidType(); 3697 3698 // If we receive a broken type, recover by assuming 'int' and 3699 // marking this declaration as invalid. 3700 if (T.isNull()) { 3701 InvalidDecl = true; 3702 T = Context.IntTy; 3703 } 3704 3705 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3706 // than a variably modified type. 3707 if (T->isVariablyModifiedType()) { 3708 bool SizeIsNegative; 3709 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3710 SizeIsNegative); 3711 if (!FixedTy.isNull()) { 3712 Diag(Loc, diag::warn_illegal_constant_array_size); 3713 T = FixedTy; 3714 } else { 3715 if (SizeIsNegative) 3716 Diag(Loc, diag::err_typecheck_negative_array_size); 3717 else 3718 Diag(Loc, diag::err_typecheck_field_variable_size); 3719 T = Context.IntTy; 3720 InvalidDecl = true; 3721 } 3722 } 3723 3724 // Fields can not have abstract class types 3725 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3726 AbstractFieldType)) 3727 InvalidDecl = true; 3728 3729 // If this is declared as a bit-field, check the bit-field. 3730 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3731 InvalidDecl = true; 3732 DeleteExpr(BitWidth); 3733 BitWidth = 0; 3734 } 3735 3736 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3737 Mutable); 3738 if (InvalidDecl) 3739 NewFD->setInvalidDecl(); 3740 3741 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3742 Diag(Loc, diag::err_duplicate_member) << II; 3743 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3744 NewFD->setInvalidDecl(); 3745 } 3746 3747 if (getLangOptions().CPlusPlus && !T->isPODType()) 3748 cast<CXXRecordDecl>(Record)->setPOD(false); 3749 3750 // FIXME: We need to pass in the attributes given an AST 3751 // representation, not a parser representation. 3752 if (D) 3753 ProcessDeclAttributes(NewFD, *D); 3754 3755 if (T.isObjCGCWeak()) 3756 Diag(Loc, diag::warn_attribute_weak_on_field); 3757 3758 NewFD->setAccess(AS); 3759 3760 // C++ [dcl.init.aggr]p1: 3761 // An aggregate is an array or a class (clause 9) with [...] no 3762 // private or protected non-static data members (clause 11). 3763 // A POD must be an aggregate. 3764 if (getLangOptions().CPlusPlus && 3765 (AS == AS_private || AS == AS_protected)) { 3766 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3767 CXXRecord->setAggregate(false); 3768 CXXRecord->setPOD(false); 3769 } 3770 3771 return NewFD; 3772} 3773 3774/// TranslateIvarVisibility - Translate visibility from a token ID to an 3775/// AST enum value. 3776static ObjCIvarDecl::AccessControl 3777TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3778 switch (ivarVisibility) { 3779 default: assert(0 && "Unknown visitibility kind"); 3780 case tok::objc_private: return ObjCIvarDecl::Private; 3781 case tok::objc_public: return ObjCIvarDecl::Public; 3782 case tok::objc_protected: return ObjCIvarDecl::Protected; 3783 case tok::objc_package: return ObjCIvarDecl::Package; 3784 } 3785} 3786 3787/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3788/// in order to create an IvarDecl object for it. 3789Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3790 SourceLocation DeclStart, 3791 Declarator &D, ExprTy *BitfieldWidth, 3792 tok::ObjCKeywordKind Visibility) { 3793 3794 IdentifierInfo *II = D.getIdentifier(); 3795 Expr *BitWidth = (Expr*)BitfieldWidth; 3796 SourceLocation Loc = DeclStart; 3797 if (II) Loc = D.getIdentifierLoc(); 3798 3799 // FIXME: Unnamed fields can be handled in various different ways, for 3800 // example, unnamed unions inject all members into the struct namespace! 3801 3802 QualType T = GetTypeForDeclarator(D, S); 3803 3804 if (BitWidth) { 3805 // 6.7.2.1p3, 6.7.2.1p4 3806 if (VerifyBitField(Loc, II, T, BitWidth)) { 3807 D.setInvalidType(); 3808 DeleteExpr(BitWidth); 3809 BitWidth = 0; 3810 } 3811 } else { 3812 // Not a bitfield. 3813 3814 // validate II. 3815 3816 } 3817 3818 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3819 // than a variably modified type. 3820 if (T->isVariablyModifiedType()) { 3821 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3822 D.setInvalidType(); 3823 } 3824 3825 // Get the visibility (access control) for this ivar. 3826 ObjCIvarDecl::AccessControl ac = 3827 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3828 : ObjCIvarDecl::None; 3829 3830 // Construct the decl. 3831 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3832 (Expr *)BitfieldWidth); 3833 3834 if (II) { 3835 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3836 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3837 && !isa<TagDecl>(PrevDecl)) { 3838 Diag(Loc, diag::err_duplicate_member) << II; 3839 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3840 NewID->setInvalidDecl(); 3841 } 3842 } 3843 3844 // Process attributes attached to the ivar. 3845 ProcessDeclAttributes(NewID, D); 3846 3847 if (D.isInvalidType()) 3848 NewID->setInvalidDecl(); 3849 3850 if (II) { 3851 // FIXME: When interfaces are DeclContexts, we'll need to add 3852 // these to the interface. 3853 S->AddDecl(DeclPtrTy::make(NewID)); 3854 IdResolver.AddDecl(NewID); 3855 } 3856 3857 return DeclPtrTy::make(NewID); 3858} 3859 3860void Sema::ActOnFields(Scope* S, 3861 SourceLocation RecLoc, DeclPtrTy RecDecl, 3862 DeclPtrTy *Fields, unsigned NumFields, 3863 SourceLocation LBrac, SourceLocation RBrac, 3864 AttributeList *Attr) { 3865 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3866 assert(EnclosingDecl && "missing record or interface decl"); 3867 3868 // If the decl this is being inserted into is invalid, then it may be a 3869 // redeclaration or some other bogus case. Don't try to add fields to it. 3870 if (EnclosingDecl->isInvalidDecl()) { 3871 // FIXME: Deallocate fields? 3872 return; 3873 } 3874 3875 3876 // Verify that all the fields are okay. 3877 unsigned NumNamedMembers = 0; 3878 llvm::SmallVector<FieldDecl*, 32> RecFields; 3879 3880 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3881 for (unsigned i = 0; i != NumFields; ++i) { 3882 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3883 3884 // Get the type for the field. 3885 Type *FDTy = FD->getType().getTypePtr(); 3886 3887 if (!FD->isAnonymousStructOrUnion()) { 3888 // Remember all fields written by the user. 3889 RecFields.push_back(FD); 3890 } 3891 3892 // If the field is already invalid for some reason, don't emit more 3893 // diagnostics about it. 3894 if (FD->isInvalidDecl()) 3895 continue; 3896 3897 // C99 6.7.2.1p2: 3898 // A structure or union shall not contain a member with 3899 // incomplete or function type (hence, a structure shall not 3900 // contain an instance of itself, but may contain a pointer to 3901 // an instance of itself), except that the last member of a 3902 // structure with more than one named member may have incomplete 3903 // array type; such a structure (and any union containing, 3904 // possibly recursively, a member that is such a structure) 3905 // shall not be a member of a structure or an element of an 3906 // array. 3907 if (FDTy->isFunctionType()) { 3908 // Field declared as a function. 3909 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3910 << FD->getDeclName(); 3911 FD->setInvalidDecl(); 3912 EnclosingDecl->setInvalidDecl(); 3913 continue; 3914 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3915 Record && Record->isStruct()) { 3916 // Flexible array member. 3917 if (NumNamedMembers < 1) { 3918 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3919 << FD->getDeclName(); 3920 FD->setInvalidDecl(); 3921 EnclosingDecl->setInvalidDecl(); 3922 continue; 3923 } 3924 // Okay, we have a legal flexible array member at the end of the struct. 3925 if (Record) 3926 Record->setHasFlexibleArrayMember(true); 3927 } else if (!FDTy->isDependentType() && 3928 RequireCompleteType(FD->getLocation(), FD->getType(), 3929 diag::err_field_incomplete)) { 3930 // Incomplete type 3931 FD->setInvalidDecl(); 3932 EnclosingDecl->setInvalidDecl(); 3933 continue; 3934 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3935 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3936 // If this is a member of a union, then entire union becomes "flexible". 3937 if (Record && Record->isUnion()) { 3938 Record->setHasFlexibleArrayMember(true); 3939 } else { 3940 // If this is a struct/class and this is not the last element, reject 3941 // it. Note that GCC supports variable sized arrays in the middle of 3942 // structures. 3943 if (i != NumFields-1) 3944 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3945 << FD->getDeclName() << FD->getType(); 3946 else { 3947 // We support flexible arrays at the end of structs in 3948 // other structs as an extension. 3949 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3950 << FD->getDeclName(); 3951 if (Record) 3952 Record->setHasFlexibleArrayMember(true); 3953 } 3954 } 3955 } 3956 } else if (FDTy->isObjCInterfaceType()) { 3957 /// A field cannot be an Objective-c object 3958 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3959 FD->setInvalidDecl(); 3960 EnclosingDecl->setInvalidDecl(); 3961 continue; 3962 } 3963 // Keep track of the number of named members. 3964 if (FD->getIdentifier()) 3965 ++NumNamedMembers; 3966 } 3967 3968 // Okay, we successfully defined 'Record'. 3969 if (Record) { 3970 Record->completeDefinition(Context); 3971 } else { 3972 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3973 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3974 ID->setIVarList(ClsFields, RecFields.size(), Context); 3975 ID->setLocEnd(RBrac); 3976 3977 // Must enforce the rule that ivars in the base classes may not be 3978 // duplicates. 3979 if (ID->getSuperClass()) { 3980 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3981 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3982 ObjCIvarDecl* Ivar = (*IVI); 3983 3984 if (IdentifierInfo *II = Ivar->getIdentifier()) { 3985 ObjCIvarDecl* prevIvar = 3986 ID->getSuperClass()->lookupInstanceVariable(Context, II); 3987 if (prevIvar) { 3988 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3989 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3990 } 3991 } 3992 } 3993 } 3994 } else if (ObjCImplementationDecl *IMPDecl = 3995 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3996 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3997 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) { 3998 // FIXME: Set the DeclContext correctly when we build the 3999 // declarations. 4000 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4001 IMPDecl->addDecl(Context, ClsFields[I]); 4002 } 4003 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4004 } 4005 } 4006 4007 if (Attr) 4008 ProcessDeclAttributeList(Record, Attr); 4009} 4010 4011EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4012 EnumConstantDecl *LastEnumConst, 4013 SourceLocation IdLoc, 4014 IdentifierInfo *Id, 4015 ExprArg val) { 4016 Expr *Val = (Expr *)val.get(); 4017 4018 llvm::APSInt EnumVal(32); 4019 QualType EltTy; 4020 if (Val && !Val->isTypeDependent()) { 4021 // Make sure to promote the operand type to int. 4022 UsualUnaryConversions(Val); 4023 if (Val != val.get()) { 4024 val.release(); 4025 val = Val; 4026 } 4027 4028 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4029 SourceLocation ExpLoc; 4030 if (!Val->isValueDependent() && 4031 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4032 Val = 0; 4033 } else { 4034 EltTy = Val->getType(); 4035 } 4036 } 4037 4038 if (!Val) { 4039 if (LastEnumConst) { 4040 // Assign the last value + 1. 4041 EnumVal = LastEnumConst->getInitVal(); 4042 ++EnumVal; 4043 4044 // Check for overflow on increment. 4045 if (EnumVal < LastEnumConst->getInitVal()) 4046 Diag(IdLoc, diag::warn_enum_value_overflow); 4047 4048 EltTy = LastEnumConst->getType(); 4049 } else { 4050 // First value, set to zero. 4051 EltTy = Context.IntTy; 4052 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4053 } 4054 } 4055 4056 val.release(); 4057 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4058 Val, EnumVal); 4059} 4060 4061 4062Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4063 DeclPtrTy lastEnumConst, 4064 SourceLocation IdLoc, 4065 IdentifierInfo *Id, 4066 SourceLocation EqualLoc, ExprTy *val) { 4067 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4068 EnumConstantDecl *LastEnumConst = 4069 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4070 Expr *Val = static_cast<Expr*>(val); 4071 4072 // The scope passed in may not be a decl scope. Zip up the scope tree until 4073 // we find one that is. 4074 S = getNonFieldDeclScope(S); 4075 4076 // Verify that there isn't already something declared with this name in this 4077 // scope. 4078 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4079 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4080 // Maybe we will complain about the shadowed template parameter. 4081 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4082 // Just pretend that we didn't see the previous declaration. 4083 PrevDecl = 0; 4084 } 4085 4086 if (PrevDecl) { 4087 // When in C++, we may get a TagDecl with the same name; in this case the 4088 // enum constant will 'hide' the tag. 4089 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4090 "Received TagDecl when not in C++!"); 4091 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4092 if (isa<EnumConstantDecl>(PrevDecl)) 4093 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4094 else 4095 Diag(IdLoc, diag::err_redefinition) << Id; 4096 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4097 if (Val) Val->Destroy(Context); 4098 return DeclPtrTy(); 4099 } 4100 } 4101 4102 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4103 IdLoc, Id, Owned(Val)); 4104 4105 // Register this decl in the current scope stack. 4106 if (New) 4107 PushOnScopeChains(New, S); 4108 4109 return DeclPtrTy::make(New); 4110} 4111 4112// FIXME: For consistency with ActOnFields(), we should have the parser 4113// pass in the source location for the left/right braces. 4114void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4115 DeclPtrTy *Elements, unsigned NumElements) { 4116 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4117 QualType EnumType = Context.getTypeDeclType(Enum); 4118 4119 // TODO: If the result value doesn't fit in an int, it must be a long or long 4120 // long value. ISO C does not support this, but GCC does as an extension, 4121 // emit a warning. 4122 unsigned IntWidth = Context.Target.getIntWidth(); 4123 4124 // Verify that all the values are okay, compute the size of the values, and 4125 // reverse the list. 4126 unsigned NumNegativeBits = 0; 4127 unsigned NumPositiveBits = 0; 4128 4129 // Keep track of whether all elements have type int. 4130 bool AllElementsInt = true; 4131 4132 for (unsigned i = 0; i != NumElements; ++i) { 4133 EnumConstantDecl *ECD = 4134 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4135 if (!ECD) continue; // Already issued a diagnostic. 4136 4137 // If the enum value doesn't fit in an int, emit an extension warning. 4138 const llvm::APSInt &InitVal = ECD->getInitVal(); 4139 assert(InitVal.getBitWidth() >= IntWidth && 4140 "Should have promoted value to int"); 4141 if (InitVal.getBitWidth() > IntWidth) { 4142 llvm::APSInt V(InitVal); 4143 V.trunc(IntWidth); 4144 V.extend(InitVal.getBitWidth()); 4145 if (V != InitVal) 4146 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4147 << InitVal.toString(10); 4148 } 4149 4150 // Keep track of the size of positive and negative values. 4151 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4152 NumPositiveBits = std::max(NumPositiveBits, 4153 (unsigned)InitVal.getActiveBits()); 4154 else 4155 NumNegativeBits = std::max(NumNegativeBits, 4156 (unsigned)InitVal.getMinSignedBits()); 4157 4158 // Keep track of whether every enum element has type int (very commmon). 4159 if (AllElementsInt) 4160 AllElementsInt = ECD->getType() == Context.IntTy; 4161 } 4162 4163 // Figure out the type that should be used for this enum. 4164 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4165 QualType BestType; 4166 unsigned BestWidth; 4167 4168 if (NumNegativeBits) { 4169 // If there is a negative value, figure out the smallest integer type (of 4170 // int/long/longlong) that fits. 4171 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4172 BestType = Context.IntTy; 4173 BestWidth = IntWidth; 4174 } else { 4175 BestWidth = Context.Target.getLongWidth(); 4176 4177 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4178 BestType = Context.LongTy; 4179 else { 4180 BestWidth = Context.Target.getLongLongWidth(); 4181 4182 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4183 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4184 BestType = Context.LongLongTy; 4185 } 4186 } 4187 } else { 4188 // If there is no negative value, figure out which of uint, ulong, ulonglong 4189 // fits. 4190 if (NumPositiveBits <= IntWidth) { 4191 BestType = Context.UnsignedIntTy; 4192 BestWidth = IntWidth; 4193 } else if (NumPositiveBits <= 4194 (BestWidth = Context.Target.getLongWidth())) { 4195 BestType = Context.UnsignedLongTy; 4196 } else { 4197 BestWidth = Context.Target.getLongLongWidth(); 4198 assert(NumPositiveBits <= BestWidth && 4199 "How could an initializer get larger than ULL?"); 4200 BestType = Context.UnsignedLongLongTy; 4201 } 4202 } 4203 4204 // Loop over all of the enumerator constants, changing their types to match 4205 // the type of the enum if needed. 4206 for (unsigned i = 0; i != NumElements; ++i) { 4207 EnumConstantDecl *ECD = 4208 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4209 if (!ECD) continue; // Already issued a diagnostic. 4210 4211 // Standard C says the enumerators have int type, but we allow, as an 4212 // extension, the enumerators to be larger than int size. If each 4213 // enumerator value fits in an int, type it as an int, otherwise type it the 4214 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4215 // that X has type 'int', not 'unsigned'. 4216 if (ECD->getType() == Context.IntTy) { 4217 // Make sure the init value is signed. 4218 llvm::APSInt IV = ECD->getInitVal(); 4219 IV.setIsSigned(true); 4220 ECD->setInitVal(IV); 4221 4222 if (getLangOptions().CPlusPlus) 4223 // C++ [dcl.enum]p4: Following the closing brace of an 4224 // enum-specifier, each enumerator has the type of its 4225 // enumeration. 4226 ECD->setType(EnumType); 4227 continue; // Already int type. 4228 } 4229 4230 // Determine whether the value fits into an int. 4231 llvm::APSInt InitVal = ECD->getInitVal(); 4232 bool FitsInInt; 4233 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4234 FitsInInt = InitVal.getActiveBits() < IntWidth; 4235 else 4236 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4237 4238 // If it fits into an integer type, force it. Otherwise force it to match 4239 // the enum decl type. 4240 QualType NewTy; 4241 unsigned NewWidth; 4242 bool NewSign; 4243 if (FitsInInt) { 4244 NewTy = Context.IntTy; 4245 NewWidth = IntWidth; 4246 NewSign = true; 4247 } else if (ECD->getType() == BestType) { 4248 // Already the right type! 4249 if (getLangOptions().CPlusPlus) 4250 // C++ [dcl.enum]p4: Following the closing brace of an 4251 // enum-specifier, each enumerator has the type of its 4252 // enumeration. 4253 ECD->setType(EnumType); 4254 continue; 4255 } else { 4256 NewTy = BestType; 4257 NewWidth = BestWidth; 4258 NewSign = BestType->isSignedIntegerType(); 4259 } 4260 4261 // Adjust the APSInt value. 4262 InitVal.extOrTrunc(NewWidth); 4263 InitVal.setIsSigned(NewSign); 4264 ECD->setInitVal(InitVal); 4265 4266 // Adjust the Expr initializer and type. 4267 if (ECD->getInitExpr()) 4268 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4269 /*isLvalue=*/false)); 4270 if (getLangOptions().CPlusPlus) 4271 // C++ [dcl.enum]p4: Following the closing brace of an 4272 // enum-specifier, each enumerator has the type of its 4273 // enumeration. 4274 ECD->setType(EnumType); 4275 else 4276 ECD->setType(NewTy); 4277 } 4278 4279 Enum->completeDefinition(Context, BestType); 4280} 4281 4282Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4283 ExprArg expr) { 4284 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 4285 4286 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4287 Loc, AsmString)); 4288} 4289