SemaDecl.cpp revision d0359af5113c1936ff3f699c7d700adff59351f2
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 Attr *attr = const_cast<Attr*>(Old->getAttrs()); 588 589 while (attr) { 590 Attr *tmp = attr; 591 attr = attr->getNext(); 592 593 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 594 tmp->setInherited(true); 595 New->addAttr(tmp); 596 } else { 597 tmp->setNext(0); 598 tmp->Destroy(C); 599 } 600 } 601 602 Old->invalidateAttrs(); 603} 604 605/// Used in MergeFunctionDecl to keep track of function parameters in 606/// C. 607struct GNUCompatibleParamWarning { 608 ParmVarDecl *OldParm; 609 ParmVarDecl *NewParm; 610 QualType PromotedType; 611}; 612 613/// MergeFunctionDecl - We just parsed a function 'New' from 614/// declarator D which has the same name and scope as a previous 615/// declaration 'Old'. Figure out how to resolve this situation, 616/// merging decls or emitting diagnostics as appropriate. 617/// 618/// In C++, New and Old must be declarations that are not 619/// overloaded. Use IsOverload to determine whether New and Old are 620/// overloaded, and to select the Old declaration that New should be 621/// merged with. 622/// 623/// Returns true if there was an error, false otherwise. 624bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 625 assert(!isa<OverloadedFunctionDecl>(OldD) && 626 "Cannot merge with an overloaded function declaration"); 627 628 // Verify the old decl was also a function. 629 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 630 if (!Old) { 631 Diag(New->getLocation(), diag::err_redefinition_different_kind) 632 << New->getDeclName(); 633 Diag(OldD->getLocation(), diag::note_previous_definition); 634 return true; 635 } 636 637 // Determine whether the previous declaration was a definition, 638 // implicit declaration, or a declaration. 639 diag::kind PrevDiag; 640 if (Old->isThisDeclarationADefinition()) 641 PrevDiag = diag::note_previous_definition; 642 else if (Old->isImplicit()) 643 PrevDiag = diag::note_previous_implicit_declaration; 644 else 645 PrevDiag = diag::note_previous_declaration; 646 647 QualType OldQType = Context.getCanonicalType(Old->getType()); 648 QualType NewQType = Context.getCanonicalType(New->getType()); 649 650 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 651 New->getStorageClass() == FunctionDecl::Static && 652 Old->getStorageClass() != FunctionDecl::Static) { 653 Diag(New->getLocation(), diag::err_static_non_static) 654 << New; 655 Diag(Old->getLocation(), PrevDiag); 656 return true; 657 } 658 659 if (getLangOptions().CPlusPlus) { 660 // (C++98 13.1p2): 661 // Certain function declarations cannot be overloaded: 662 // -- Function declarations that differ only in the return type 663 // cannot be overloaded. 664 QualType OldReturnType 665 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 666 QualType NewReturnType 667 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 668 if (OldReturnType != NewReturnType) { 669 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 670 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 671 return true; 672 } 673 674 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 675 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 676 if (OldMethod && NewMethod && 677 OldMethod->getLexicalDeclContext() == 678 NewMethod->getLexicalDeclContext()) { 679 // -- Member function declarations with the same name and the 680 // same parameter types cannot be overloaded if any of them 681 // is a static member function declaration. 682 if (OldMethod->isStatic() || NewMethod->isStatic()) { 683 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 684 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 685 return true; 686 } 687 688 // C++ [class.mem]p1: 689 // [...] A member shall not be declared twice in the 690 // member-specification, except that a nested class or member 691 // class template can be declared and then later defined. 692 unsigned NewDiag; 693 if (isa<CXXConstructorDecl>(OldMethod)) 694 NewDiag = diag::err_constructor_redeclared; 695 else if (isa<CXXDestructorDecl>(NewMethod)) 696 NewDiag = diag::err_destructor_redeclared; 697 else if (isa<CXXConversionDecl>(NewMethod)) 698 NewDiag = diag::err_conv_function_redeclared; 699 else 700 NewDiag = diag::err_member_redeclared; 701 702 Diag(New->getLocation(), NewDiag); 703 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 704 } 705 706 // (C++98 8.3.5p3): 707 // All declarations for a function shall agree exactly in both the 708 // return type and the parameter-type-list. 709 if (OldQType == NewQType) 710 return MergeCompatibleFunctionDecls(New, Old); 711 712 // Fall through for conflicting redeclarations and redefinitions. 713 } 714 715 // C: Function types need to be compatible, not identical. This handles 716 // duplicate function decls like "void f(int); void f(enum X);" properly. 717 if (!getLangOptions().CPlusPlus && 718 Context.typesAreCompatible(OldQType, NewQType)) { 719 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 720 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 721 const FunctionProtoType *OldProto = 0; 722 if (isa<FunctionNoProtoType>(NewFuncType) && 723 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 724 // The old declaration provided a function prototype, but the 725 // new declaration does not. Merge in the prototype. 726 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 727 OldProto->arg_type_end()); 728 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 729 &ParamTypes[0], ParamTypes.size(), 730 OldProto->isVariadic(), 731 OldProto->getTypeQuals()); 732 New->setType(NewQType); 733 New->setInheritedPrototype(); 734 735 // Synthesize a parameter for each argument type. 736 llvm::SmallVector<ParmVarDecl*, 16> Params; 737 for (FunctionProtoType::arg_type_iterator 738 ParamType = OldProto->arg_type_begin(), 739 ParamEnd = OldProto->arg_type_end(); 740 ParamType != ParamEnd; ++ParamType) { 741 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 742 SourceLocation(), 0, 743 *ParamType, VarDecl::None, 744 0); 745 Param->setImplicit(); 746 Params.push_back(Param); 747 } 748 749 New->setParams(Context, &Params[0], Params.size()); 750 } 751 752 return MergeCompatibleFunctionDecls(New, Old); 753 } 754 755 // GNU C permits a K&R definition to follow a prototype declaration 756 // if the declared types of the parameters in the K&R definition 757 // match the types in the prototype declaration, even when the 758 // promoted types of the parameters from the K&R definition differ 759 // from the types in the prototype. GCC then keeps the types from 760 // the prototype. 761 if (!getLangOptions().CPlusPlus && 762 !getLangOptions().NoExtensions && 763 Old->hasPrototype() && !New->hasPrototype() && 764 New->getType()->getAsFunctionProtoType() && 765 Old->getNumParams() == New->getNumParams()) { 766 llvm::SmallVector<QualType, 16> ArgTypes; 767 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 768 const FunctionProtoType *OldProto 769 = Old->getType()->getAsFunctionProtoType(); 770 const FunctionProtoType *NewProto 771 = New->getType()->getAsFunctionProtoType(); 772 773 // Determine whether this is the GNU C extension. 774 bool GNUCompatible = 775 Context.typesAreCompatible(OldProto->getResultType(), 776 NewProto->getResultType()) && 777 (OldProto->isVariadic() == NewProto->isVariadic()); 778 for (unsigned Idx = 0, End = Old->getNumParams(); 779 GNUCompatible && Idx != End; ++Idx) { 780 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 781 ParmVarDecl *NewParm = New->getParamDecl(Idx); 782 if (Context.typesAreCompatible(OldParm->getType(), 783 NewProto->getArgType(Idx))) { 784 ArgTypes.push_back(NewParm->getType()); 785 } else if (Context.typesAreCompatible(OldParm->getType(), 786 NewParm->getType())) { 787 GNUCompatibleParamWarning Warn 788 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 789 Warnings.push_back(Warn); 790 ArgTypes.push_back(NewParm->getType()); 791 } else 792 GNUCompatible = false; 793 } 794 795 if (GNUCompatible) { 796 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 797 Diag(Warnings[Warn].NewParm->getLocation(), 798 diag::ext_param_promoted_not_compatible_with_prototype) 799 << Warnings[Warn].PromotedType 800 << Warnings[Warn].OldParm->getType(); 801 Diag(Warnings[Warn].OldParm->getLocation(), 802 diag::note_previous_declaration); 803 } 804 805 New->setType(Context.getFunctionType(NewProto->getResultType(), 806 &ArgTypes[0], ArgTypes.size(), 807 NewProto->isVariadic(), 808 NewProto->getTypeQuals())); 809 return MergeCompatibleFunctionDecls(New, Old); 810 } 811 812 // Fall through to diagnose conflicting types. 813 } 814 815 // A function that has already been declared has been redeclared or defined 816 // with a different type- show appropriate diagnostic 817 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 818 // The user has declared a builtin function with an incompatible 819 // signature. 820 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 821 // The function the user is redeclaring is a library-defined 822 // function like 'malloc' or 'printf'. Warn about the 823 // redeclaration, then pretend that we don't know about this 824 // library built-in. 825 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 826 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 827 << Old << Old->getType(); 828 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 829 Old->setInvalidDecl(); 830 return false; 831 } 832 833 PrevDiag = diag::note_previous_builtin_declaration; 834 } 835 836 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 837 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 838 return true; 839} 840 841/// \brief Completes the merge of two function declarations that are 842/// known to be compatible. 843/// 844/// This routine handles the merging of attributes and other 845/// properties of function declarations form the old declaration to 846/// the new declaration, once we know that New is in fact a 847/// redeclaration of Old. 848/// 849/// \returns false 850bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 851 // Merge the attributes 852 MergeAttributes(New, Old, Context); 853 854 // Merge the storage class. 855 New->setStorageClass(Old->getStorageClass()); 856 857 // Merge "inline" 858 if (Old->isInline()) 859 New->setInline(true); 860 861 // If this function declaration by itself qualifies as a C99 inline 862 // definition (C99 6.7.4p6), but the previous definition did not, 863 // then the function is not a C99 inline definition. 864 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 865 New->setC99InlineDefinition(false); 866 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 867 // Mark all preceding definitions as not being C99 inline definitions. 868 for (const FunctionDecl *Prev = Old; Prev; 869 Prev = Prev->getPreviousDeclaration()) 870 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 871 } 872 873 // Merge "pure" flag. 874 if (Old->isPure()) 875 New->setPure(); 876 877 // Merge the "deleted" flag. 878 if (Old->isDeleted()) 879 New->setDeleted(); 880 881 if (getLangOptions().CPlusPlus) 882 return MergeCXXFunctionDecl(New, Old); 883 884 return false; 885} 886 887/// MergeVarDecl - We just parsed a variable 'New' which has the same name 888/// and scope as a previous declaration 'Old'. Figure out how to resolve this 889/// situation, merging decls or emitting diagnostics as appropriate. 890/// 891/// Tentative definition rules (C99 6.9.2p2) are checked by 892/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 893/// definitions here, since the initializer hasn't been attached. 894/// 895void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 896 // If either decl is invalid, make sure the new one is marked invalid and 897 // don't do any other checking. 898 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 899 return New->setInvalidDecl(); 900 901 // Verify the old decl was also a variable. 902 VarDecl *Old = dyn_cast<VarDecl>(OldD); 903 if (!Old) { 904 Diag(New->getLocation(), diag::err_redefinition_different_kind) 905 << New->getDeclName(); 906 Diag(OldD->getLocation(), diag::note_previous_definition); 907 return New->setInvalidDecl(); 908 } 909 910 MergeAttributes(New, Old, Context); 911 912 // Merge the types 913 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 914 if (MergedT.isNull()) { 915 Diag(New->getLocation(), diag::err_redefinition_different_type) 916 << New->getDeclName(); 917 Diag(Old->getLocation(), diag::note_previous_definition); 918 return New->setInvalidDecl(); 919 } 920 New->setType(MergedT); 921 922 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 923 if (New->getStorageClass() == VarDecl::Static && 924 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 925 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 926 Diag(Old->getLocation(), diag::note_previous_definition); 927 return New->setInvalidDecl(); 928 } 929 // C99 6.2.2p4: 930 // For an identifier declared with the storage-class specifier 931 // extern in a scope in which a prior declaration of that 932 // identifier is visible,23) if the prior declaration specifies 933 // internal or external linkage, the linkage of the identifier at 934 // the later declaration is the same as the linkage specified at 935 // the prior declaration. If no prior declaration is visible, or 936 // if the prior declaration specifies no linkage, then the 937 // identifier has external linkage. 938 if (New->hasExternalStorage() && Old->hasLinkage()) 939 /* Okay */; 940 else if (New->getStorageClass() != VarDecl::Static && 941 Old->getStorageClass() == VarDecl::Static) { 942 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 943 Diag(Old->getLocation(), diag::note_previous_definition); 944 return New->setInvalidDecl(); 945 } 946 947 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 948 949 // FIXME: The test for external storage here seems wrong? We still 950 // need to check for mismatches. 951 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 952 // Don't complain about out-of-line definitions of static members. 953 !(Old->getLexicalDeclContext()->isRecord() && 954 !New->getLexicalDeclContext()->isRecord())) { 955 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 956 Diag(Old->getLocation(), diag::note_previous_definition); 957 return New->setInvalidDecl(); 958 } 959 960 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 961 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 962 Diag(Old->getLocation(), diag::note_previous_definition); 963 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 964 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 965 Diag(Old->getLocation(), diag::note_previous_definition); 966 } 967 968 // Keep a chain of previous declarations. 969 New->setPreviousDeclaration(Old); 970} 971 972/// CheckParmsForFunctionDef - Check that the parameters of the given 973/// function are appropriate for the definition of a function. This 974/// takes care of any checks that cannot be performed on the 975/// declaration itself, e.g., that the types of each of the function 976/// parameters are complete. 977bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 978 bool HasInvalidParm = false; 979 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 980 ParmVarDecl *Param = FD->getParamDecl(p); 981 982 // C99 6.7.5.3p4: the parameters in a parameter type list in a 983 // function declarator that is part of a function definition of 984 // that function shall not have incomplete type. 985 // 986 // This is also C++ [dcl.fct]p6. 987 if (!Param->isInvalidDecl() && 988 RequireCompleteType(Param->getLocation(), Param->getType(), 989 diag::err_typecheck_decl_incomplete_type)) { 990 Param->setInvalidDecl(); 991 HasInvalidParm = true; 992 } 993 994 // C99 6.9.1p5: If the declarator includes a parameter type list, the 995 // declaration of each parameter shall include an identifier. 996 if (Param->getIdentifier() == 0 && 997 !Param->isImplicit() && 998 !getLangOptions().CPlusPlus) 999 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1000 } 1001 1002 return HasInvalidParm; 1003} 1004 1005/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1006/// no declarator (e.g. "struct foo;") is parsed. 1007Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1008 // FIXME: Error on auto/register at file scope 1009 // FIXME: Error on inline/virtual/explicit 1010 // FIXME: Error on invalid restrict 1011 // FIXME: Warn on useless __thread 1012 // FIXME: Warn on useless const/volatile 1013 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1014 // FIXME: Warn on useless attributes 1015 1016 TagDecl *Tag = 0; 1017 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1018 DS.getTypeSpecType() == DeclSpec::TST_struct || 1019 DS.getTypeSpecType() == DeclSpec::TST_union || 1020 DS.getTypeSpecType() == DeclSpec::TST_enum) 1021 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1022 1023 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1024 if (!Record->getDeclName() && Record->isDefinition() && 1025 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1026 if (getLangOptions().CPlusPlus || 1027 Record->getDeclContext()->isRecord()) 1028 return BuildAnonymousStructOrUnion(S, DS, Record); 1029 1030 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1031 << DS.getSourceRange(); 1032 } 1033 1034 // Microsoft allows unnamed struct/union fields. Don't complain 1035 // about them. 1036 // FIXME: Should we support Microsoft's extensions in this area? 1037 if (Record->getDeclName() && getLangOptions().Microsoft) 1038 return DeclPtrTy::make(Tag); 1039 } 1040 1041 if (!DS.isMissingDeclaratorOk() && 1042 DS.getTypeSpecType() != DeclSpec::TST_error) { 1043 // Warn about typedefs of enums without names, since this is an 1044 // extension in both Microsoft an GNU. 1045 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1046 Tag && isa<EnumDecl>(Tag)) { 1047 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1048 << DS.getSourceRange(); 1049 return DeclPtrTy::make(Tag); 1050 } 1051 1052 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1053 << DS.getSourceRange(); 1054 return DeclPtrTy(); 1055 } 1056 1057 return DeclPtrTy::make(Tag); 1058} 1059 1060/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1061/// anonymous struct or union AnonRecord into the owning context Owner 1062/// and scope S. This routine will be invoked just after we realize 1063/// that an unnamed union or struct is actually an anonymous union or 1064/// struct, e.g., 1065/// 1066/// @code 1067/// union { 1068/// int i; 1069/// float f; 1070/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1071/// // f into the surrounding scope.x 1072/// @endcode 1073/// 1074/// This routine is recursive, injecting the names of nested anonymous 1075/// structs/unions into the owning context and scope as well. 1076bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1077 RecordDecl *AnonRecord) { 1078 bool Invalid = false; 1079 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1080 FEnd = AnonRecord->field_end(Context); 1081 F != FEnd; ++F) { 1082 if ((*F)->getDeclName()) { 1083 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1084 LookupOrdinaryName, true); 1085 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1086 // C++ [class.union]p2: 1087 // The names of the members of an anonymous union shall be 1088 // distinct from the names of any other entity in the 1089 // scope in which the anonymous union is declared. 1090 unsigned diagKind 1091 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1092 : diag::err_anonymous_struct_member_redecl; 1093 Diag((*F)->getLocation(), diagKind) 1094 << (*F)->getDeclName(); 1095 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1096 Invalid = true; 1097 } else { 1098 // C++ [class.union]p2: 1099 // For the purpose of name lookup, after the anonymous union 1100 // definition, the members of the anonymous union are 1101 // considered to have been defined in the scope in which the 1102 // anonymous union is declared. 1103 Owner->makeDeclVisibleInContext(Context, *F); 1104 S->AddDecl(DeclPtrTy::make(*F)); 1105 IdResolver.AddDecl(*F); 1106 } 1107 } else if (const RecordType *InnerRecordType 1108 = (*F)->getType()->getAsRecordType()) { 1109 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1110 if (InnerRecord->isAnonymousStructOrUnion()) 1111 Invalid = Invalid || 1112 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1113 } 1114 } 1115 1116 return Invalid; 1117} 1118 1119/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1120/// anonymous structure or union. Anonymous unions are a C++ feature 1121/// (C++ [class.union]) and a GNU C extension; anonymous structures 1122/// are a GNU C and GNU C++ extension. 1123Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1124 RecordDecl *Record) { 1125 DeclContext *Owner = Record->getDeclContext(); 1126 1127 // Diagnose whether this anonymous struct/union is an extension. 1128 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1129 Diag(Record->getLocation(), diag::ext_anonymous_union); 1130 else if (!Record->isUnion()) 1131 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1132 1133 // C and C++ require different kinds of checks for anonymous 1134 // structs/unions. 1135 bool Invalid = false; 1136 if (getLangOptions().CPlusPlus) { 1137 const char* PrevSpec = 0; 1138 // C++ [class.union]p3: 1139 // Anonymous unions declared in a named namespace or in the 1140 // global namespace shall be declared static. 1141 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1142 (isa<TranslationUnitDecl>(Owner) || 1143 (isa<NamespaceDecl>(Owner) && 1144 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1145 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1146 Invalid = true; 1147 1148 // Recover by adding 'static'. 1149 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1150 } 1151 // C++ [class.union]p3: 1152 // A storage class is not allowed in a declaration of an 1153 // anonymous union in a class scope. 1154 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1155 isa<RecordDecl>(Owner)) { 1156 Diag(DS.getStorageClassSpecLoc(), 1157 diag::err_anonymous_union_with_storage_spec); 1158 Invalid = true; 1159 1160 // Recover by removing the storage specifier. 1161 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1162 PrevSpec); 1163 } 1164 1165 // C++ [class.union]p2: 1166 // The member-specification of an anonymous union shall only 1167 // define non-static data members. [Note: nested types and 1168 // functions cannot be declared within an anonymous union. ] 1169 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1170 MemEnd = Record->decls_end(Context); 1171 Mem != MemEnd; ++Mem) { 1172 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1173 // C++ [class.union]p3: 1174 // An anonymous union shall not have private or protected 1175 // members (clause 11). 1176 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1177 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1178 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1179 Invalid = true; 1180 } 1181 } else if ((*Mem)->isImplicit()) { 1182 // Any implicit members are fine. 1183 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1184 // This is a type that showed up in an 1185 // elaborated-type-specifier inside the anonymous struct or 1186 // union, but which actually declares a type outside of the 1187 // anonymous struct or union. It's okay. 1188 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1189 if (!MemRecord->isAnonymousStructOrUnion() && 1190 MemRecord->getDeclName()) { 1191 // This is a nested type declaration. 1192 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1193 << (int)Record->isUnion(); 1194 Invalid = true; 1195 } 1196 } else { 1197 // We have something that isn't a non-static data 1198 // member. Complain about it. 1199 unsigned DK = diag::err_anonymous_record_bad_member; 1200 if (isa<TypeDecl>(*Mem)) 1201 DK = diag::err_anonymous_record_with_type; 1202 else if (isa<FunctionDecl>(*Mem)) 1203 DK = diag::err_anonymous_record_with_function; 1204 else if (isa<VarDecl>(*Mem)) 1205 DK = diag::err_anonymous_record_with_static; 1206 Diag((*Mem)->getLocation(), DK) 1207 << (int)Record->isUnion(); 1208 Invalid = true; 1209 } 1210 } 1211 } 1212 1213 if (!Record->isUnion() && !Owner->isRecord()) { 1214 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1215 << (int)getLangOptions().CPlusPlus; 1216 Invalid = true; 1217 } 1218 1219 // Create a declaration for this anonymous struct/union. 1220 NamedDecl *Anon = 0; 1221 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1222 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1223 /*IdentifierInfo=*/0, 1224 Context.getTypeDeclType(Record), 1225 /*BitWidth=*/0, /*Mutable=*/false); 1226 Anon->setAccess(AS_public); 1227 if (getLangOptions().CPlusPlus) 1228 FieldCollector->Add(cast<FieldDecl>(Anon)); 1229 } else { 1230 VarDecl::StorageClass SC; 1231 switch (DS.getStorageClassSpec()) { 1232 default: assert(0 && "Unknown storage class!"); 1233 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1234 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1235 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1236 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1237 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1238 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1239 case DeclSpec::SCS_mutable: 1240 // mutable can only appear on non-static class members, so it's always 1241 // an error here 1242 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1243 Invalid = true; 1244 SC = VarDecl::None; 1245 break; 1246 } 1247 1248 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1249 /*IdentifierInfo=*/0, 1250 Context.getTypeDeclType(Record), 1251 SC, DS.getSourceRange().getBegin()); 1252 } 1253 Anon->setImplicit(); 1254 1255 // Add the anonymous struct/union object to the current 1256 // context. We'll be referencing this object when we refer to one of 1257 // its members. 1258 Owner->addDecl(Context, Anon); 1259 1260 // Inject the members of the anonymous struct/union into the owning 1261 // context and into the identifier resolver chain for name lookup 1262 // purposes. 1263 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1264 Invalid = true; 1265 1266 // Mark this as an anonymous struct/union type. Note that we do not 1267 // do this until after we have already checked and injected the 1268 // members of this anonymous struct/union type, because otherwise 1269 // the members could be injected twice: once by DeclContext when it 1270 // builds its lookup table, and once by 1271 // InjectAnonymousStructOrUnionMembers. 1272 Record->setAnonymousStructOrUnion(true); 1273 1274 if (Invalid) 1275 Anon->setInvalidDecl(); 1276 1277 return DeclPtrTy::make(Anon); 1278} 1279 1280 1281/// GetNameForDeclarator - Determine the full declaration name for the 1282/// given Declarator. 1283DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1284 switch (D.getKind()) { 1285 case Declarator::DK_Abstract: 1286 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1287 return DeclarationName(); 1288 1289 case Declarator::DK_Normal: 1290 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1291 return DeclarationName(D.getIdentifier()); 1292 1293 case Declarator::DK_Constructor: { 1294 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1295 Ty = Context.getCanonicalType(Ty); 1296 return Context.DeclarationNames.getCXXConstructorName(Ty); 1297 } 1298 1299 case Declarator::DK_Destructor: { 1300 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1301 Ty = Context.getCanonicalType(Ty); 1302 return Context.DeclarationNames.getCXXDestructorName(Ty); 1303 } 1304 1305 case Declarator::DK_Conversion: { 1306 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1307 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1308 Ty = Context.getCanonicalType(Ty); 1309 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1310 } 1311 1312 case Declarator::DK_Operator: 1313 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1314 return Context.DeclarationNames.getCXXOperatorName( 1315 D.getOverloadedOperator()); 1316 } 1317 1318 assert(false && "Unknown name kind"); 1319 return DeclarationName(); 1320} 1321 1322/// isNearlyMatchingFunction - Determine whether the C++ functions 1323/// Declaration and Definition are "nearly" matching. This heuristic 1324/// is used to improve diagnostics in the case where an out-of-line 1325/// function definition doesn't match any declaration within 1326/// the class or namespace. 1327static bool isNearlyMatchingFunction(ASTContext &Context, 1328 FunctionDecl *Declaration, 1329 FunctionDecl *Definition) { 1330 if (Declaration->param_size() != Definition->param_size()) 1331 return false; 1332 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1333 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1334 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1335 1336 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1337 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1338 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1339 return false; 1340 } 1341 1342 return true; 1343} 1344 1345Sema::DeclPtrTy 1346Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1347 DeclarationName Name = GetNameForDeclarator(D); 1348 1349 // All of these full declarators require an identifier. If it doesn't have 1350 // one, the ParsedFreeStandingDeclSpec action should be used. 1351 if (!Name) { 1352 if (!D.isInvalidType()) // Reject this if we think it is valid. 1353 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1354 diag::err_declarator_need_ident) 1355 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1356 return DeclPtrTy(); 1357 } 1358 1359 // The scope passed in may not be a decl scope. Zip up the scope tree until 1360 // we find one that is. 1361 while ((S->getFlags() & Scope::DeclScope) == 0 || 1362 (S->getFlags() & Scope::TemplateParamScope) != 0) 1363 S = S->getParent(); 1364 1365 DeclContext *DC; 1366 NamedDecl *PrevDecl; 1367 NamedDecl *New; 1368 1369 QualType R = GetTypeForDeclarator(D, S); 1370 1371 // See if this is a redefinition of a variable in the same scope. 1372 if (D.getCXXScopeSpec().isInvalid()) { 1373 DC = CurContext; 1374 PrevDecl = 0; 1375 D.setInvalidType(); 1376 } else if (!D.getCXXScopeSpec().isSet()) { 1377 LookupNameKind NameKind = LookupOrdinaryName; 1378 1379 // If the declaration we're planning to build will be a function 1380 // or object with linkage, then look for another declaration with 1381 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1382 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1383 /* Do nothing*/; 1384 else if (R->isFunctionType()) { 1385 if (CurContext->isFunctionOrMethod()) 1386 NameKind = LookupRedeclarationWithLinkage; 1387 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1388 NameKind = LookupRedeclarationWithLinkage; 1389 1390 DC = CurContext; 1391 PrevDecl = LookupName(S, Name, NameKind, true, 1392 D.getDeclSpec().getStorageClassSpec() != 1393 DeclSpec::SCS_static, 1394 D.getIdentifierLoc()); 1395 } else { // Something like "int foo::x;" 1396 DC = computeDeclContext(D.getCXXScopeSpec()); 1397 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1398 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1399 1400 // C++ 7.3.1.2p2: 1401 // Members (including explicit specializations of templates) of a named 1402 // namespace can also be defined outside that namespace by explicit 1403 // qualification of the name being defined, provided that the entity being 1404 // defined was already declared in the namespace and the definition appears 1405 // after the point of declaration in a namespace that encloses the 1406 // declarations namespace. 1407 // 1408 // Note that we only check the context at this point. We don't yet 1409 // have enough information to make sure that PrevDecl is actually 1410 // the declaration we want to match. For example, given: 1411 // 1412 // class X { 1413 // void f(); 1414 // void f(float); 1415 // }; 1416 // 1417 // void X::f(int) { } // ill-formed 1418 // 1419 // In this case, PrevDecl will point to the overload set 1420 // containing the two f's declared in X, but neither of them 1421 // matches. 1422 1423 // First check whether we named the global scope. 1424 if (isa<TranslationUnitDecl>(DC)) { 1425 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1426 << Name << D.getCXXScopeSpec().getRange(); 1427 } else if (!CurContext->Encloses(DC)) { 1428 // The qualifying scope doesn't enclose the original declaration. 1429 // Emit diagnostic based on current scope. 1430 SourceLocation L = D.getIdentifierLoc(); 1431 SourceRange R = D.getCXXScopeSpec().getRange(); 1432 if (isa<FunctionDecl>(CurContext)) 1433 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1434 else 1435 Diag(L, diag::err_invalid_declarator_scope) 1436 << Name << cast<NamedDecl>(DC) << R; 1437 D.setInvalidType(); 1438 } 1439 } 1440 1441 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1442 // Maybe we will complain about the shadowed template parameter. 1443 if (!D.isInvalidType()) 1444 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1445 D.setInvalidType(); 1446 1447 // Just pretend that we didn't see the previous declaration. 1448 PrevDecl = 0; 1449 } 1450 1451 // In C++, the previous declaration we find might be a tag type 1452 // (class or enum). In this case, the new declaration will hide the 1453 // tag type. Note that this does does not apply if we're declaring a 1454 // typedef (C++ [dcl.typedef]p4). 1455 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1456 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1457 PrevDecl = 0; 1458 1459 bool Redeclaration = false; 1460 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1461 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1462 } else if (R->isFunctionType()) { 1463 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1464 IsFunctionDefinition, Redeclaration); 1465 } else { 1466 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1467 } 1468 1469 if (New == 0) 1470 return DeclPtrTy(); 1471 1472 // If this has an identifier and is not an invalid redeclaration, 1473 // add it to the scope stack. 1474 if (Name && !(Redeclaration && New->isInvalidDecl())) 1475 PushOnScopeChains(New, S); 1476 1477 return DeclPtrTy::make(New); 1478} 1479 1480/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1481/// types into constant array types in certain situations which would otherwise 1482/// be errors (for GCC compatibility). 1483static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1484 ASTContext &Context, 1485 bool &SizeIsNegative) { 1486 // This method tries to turn a variable array into a constant 1487 // array even when the size isn't an ICE. This is necessary 1488 // for compatibility with code that depends on gcc's buggy 1489 // constant expression folding, like struct {char x[(int)(char*)2];} 1490 SizeIsNegative = false; 1491 1492 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1493 QualType Pointee = PTy->getPointeeType(); 1494 QualType FixedType = 1495 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1496 if (FixedType.isNull()) return FixedType; 1497 FixedType = Context.getPointerType(FixedType); 1498 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1499 return FixedType; 1500 } 1501 1502 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1503 if (!VLATy) 1504 return QualType(); 1505 // FIXME: We should probably handle this case 1506 if (VLATy->getElementType()->isVariablyModifiedType()) 1507 return QualType(); 1508 1509 Expr::EvalResult EvalResult; 1510 if (!VLATy->getSizeExpr() || 1511 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1512 !EvalResult.Val.isInt()) 1513 return QualType(); 1514 1515 llvm::APSInt &Res = EvalResult.Val.getInt(); 1516 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1517 return Context.getConstantArrayType(VLATy->getElementType(), 1518 Res, ArrayType::Normal, 0); 1519 1520 SizeIsNegative = true; 1521 return QualType(); 1522} 1523 1524/// \brief Register the given locally-scoped external C declaration so 1525/// that it can be found later for redeclarations 1526void 1527Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1528 Scope *S) { 1529 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1530 "Decl is not a locally-scoped decl!"); 1531 // Note that we have a locally-scoped external with this name. 1532 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1533 1534 if (!PrevDecl) 1535 return; 1536 1537 // If there was a previous declaration of this variable, it may be 1538 // in our identifier chain. Update the identifier chain with the new 1539 // declaration. 1540 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1541 // The previous declaration was found on the identifer resolver 1542 // chain, so remove it from its scope. 1543 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1544 S = S->getParent(); 1545 1546 if (S) 1547 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1548 } 1549} 1550 1551/// \brief Diagnose function specifiers on a declaration of an identifier that 1552/// does not identify a function. 1553void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1554 // FIXME: We should probably indicate the identifier in question to avoid 1555 // confusion for constructs like "inline int a(), b;" 1556 if (D.getDeclSpec().isInlineSpecified()) 1557 Diag(D.getDeclSpec().getInlineSpecLoc(), 1558 diag::err_inline_non_function); 1559 1560 if (D.getDeclSpec().isVirtualSpecified()) 1561 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1562 diag::err_virtual_non_function); 1563 1564 if (D.getDeclSpec().isExplicitSpecified()) 1565 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1566 diag::err_explicit_non_function); 1567} 1568 1569NamedDecl* 1570Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1571 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1572 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1573 if (D.getCXXScopeSpec().isSet()) { 1574 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1575 << D.getCXXScopeSpec().getRange(); 1576 D.setInvalidType(); 1577 // Pretend we didn't see the scope specifier. 1578 DC = 0; 1579 } 1580 1581 if (getLangOptions().CPlusPlus) { 1582 // Check that there are no default arguments (C++ only). 1583 CheckExtraCXXDefaultArguments(D); 1584 } 1585 1586 DiagnoseFunctionSpecifiers(D); 1587 1588 if (D.getDeclSpec().isThreadSpecified()) 1589 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1590 1591 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1592 if (!NewTD) return 0; 1593 1594 if (D.isInvalidType()) 1595 NewTD->setInvalidDecl(); 1596 1597 // Handle attributes prior to checking for duplicates in MergeVarDecl 1598 ProcessDeclAttributes(NewTD, D); 1599 // Merge the decl with the existing one if appropriate. If the decl is 1600 // in an outer scope, it isn't the same thing. 1601 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1602 Redeclaration = true; 1603 MergeTypeDefDecl(NewTD, PrevDecl); 1604 } 1605 1606 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1607 // then it shall have block scope. 1608 QualType T = NewTD->getUnderlyingType(); 1609 if (T->isVariablyModifiedType()) { 1610 CurFunctionNeedsScopeChecking = true; 1611 1612 if (S->getFnParent() == 0) { 1613 bool SizeIsNegative; 1614 QualType FixedTy = 1615 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1616 if (!FixedTy.isNull()) { 1617 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1618 NewTD->setUnderlyingType(FixedTy); 1619 } else { 1620 if (SizeIsNegative) 1621 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1622 else if (T->isVariableArrayType()) 1623 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1624 else 1625 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1626 NewTD->setInvalidDecl(); 1627 } 1628 } 1629 } 1630 return NewTD; 1631} 1632 1633/// \brief Determines whether the given declaration is an out-of-scope 1634/// previous declaration. 1635/// 1636/// This routine should be invoked when name lookup has found a 1637/// previous declaration (PrevDecl) that is not in the scope where a 1638/// new declaration by the same name is being introduced. If the new 1639/// declaration occurs in a local scope, previous declarations with 1640/// linkage may still be considered previous declarations (C99 1641/// 6.2.2p4-5, C++ [basic.link]p6). 1642/// 1643/// \param PrevDecl the previous declaration found by name 1644/// lookup 1645/// 1646/// \param DC the context in which the new declaration is being 1647/// declared. 1648/// 1649/// \returns true if PrevDecl is an out-of-scope previous declaration 1650/// for a new delcaration with the same name. 1651static bool 1652isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1653 ASTContext &Context) { 1654 if (!PrevDecl) 1655 return 0; 1656 1657 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1658 // case we need to check each of the overloaded functions. 1659 if (!PrevDecl->hasLinkage()) 1660 return false; 1661 1662 if (Context.getLangOptions().CPlusPlus) { 1663 // C++ [basic.link]p6: 1664 // If there is a visible declaration of an entity with linkage 1665 // having the same name and type, ignoring entities declared 1666 // outside the innermost enclosing namespace scope, the block 1667 // scope declaration declares that same entity and receives the 1668 // linkage of the previous declaration. 1669 DeclContext *OuterContext = DC->getLookupContext(); 1670 if (!OuterContext->isFunctionOrMethod()) 1671 // This rule only applies to block-scope declarations. 1672 return false; 1673 else { 1674 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1675 if (PrevOuterContext->isRecord()) 1676 // We found a member function: ignore it. 1677 return false; 1678 else { 1679 // Find the innermost enclosing namespace for the new and 1680 // previous declarations. 1681 while (!OuterContext->isFileContext()) 1682 OuterContext = OuterContext->getParent(); 1683 while (!PrevOuterContext->isFileContext()) 1684 PrevOuterContext = PrevOuterContext->getParent(); 1685 1686 // The previous declaration is in a different namespace, so it 1687 // isn't the same function. 1688 if (OuterContext->getPrimaryContext() != 1689 PrevOuterContext->getPrimaryContext()) 1690 return false; 1691 } 1692 } 1693 } 1694 1695 return true; 1696} 1697 1698NamedDecl* 1699Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1700 QualType R,NamedDecl* PrevDecl, 1701 bool &Redeclaration) { 1702 DeclarationName Name = GetNameForDeclarator(D); 1703 1704 // Check that there are no default arguments (C++ only). 1705 if (getLangOptions().CPlusPlus) 1706 CheckExtraCXXDefaultArguments(D); 1707 1708 VarDecl *NewVD; 1709 VarDecl::StorageClass SC; 1710 switch (D.getDeclSpec().getStorageClassSpec()) { 1711 default: assert(0 && "Unknown storage class!"); 1712 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1713 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1714 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1715 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1716 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1717 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1718 case DeclSpec::SCS_mutable: 1719 // mutable can only appear on non-static class members, so it's always 1720 // an error here 1721 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1722 D.setInvalidType(); 1723 SC = VarDecl::None; 1724 break; 1725 } 1726 1727 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1728 if (!II) { 1729 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1730 << Name.getAsString(); 1731 return 0; 1732 } 1733 1734 DiagnoseFunctionSpecifiers(D); 1735 1736 if (!DC->isRecord() && S->getFnParent() == 0) { 1737 // C99 6.9p2: The storage-class specifiers auto and register shall not 1738 // appear in the declaration specifiers in an external declaration. 1739 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1740 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1741 D.setInvalidType(); 1742 } 1743 } 1744 if (DC->isRecord() && !CurContext->isRecord()) { 1745 // This is an out-of-line definition of a static data member. 1746 if (SC == VarDecl::Static) { 1747 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1748 diag::err_static_out_of_line) 1749 << CodeModificationHint::CreateRemoval( 1750 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1751 } else if (SC == VarDecl::None) 1752 SC = VarDecl::Static; 1753 } 1754 1755 // The variable can not 1756 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1757 II, R, SC, 1758 // FIXME: Move to DeclGroup... 1759 D.getDeclSpec().getSourceRange().getBegin()); 1760 1761 if (D.isInvalidType()) 1762 NewVD->setInvalidDecl(); 1763 1764 if (D.getDeclSpec().isThreadSpecified()) { 1765 if (NewVD->hasLocalStorage()) 1766 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1767 else if (!Context.Target.isTLSSupported()) 1768 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1769 else 1770 NewVD->setThreadSpecified(true); 1771 } 1772 1773 // Set the lexical context. If the declarator has a C++ scope specifier, the 1774 // lexical context will be different from the semantic context. 1775 NewVD->setLexicalDeclContext(CurContext); 1776 1777 // Handle attributes prior to checking for duplicates in MergeVarDecl 1778 ProcessDeclAttributes(NewVD, D); 1779 1780 // Handle GNU asm-label extension (encoded as an attribute). 1781 if (Expr *E = (Expr*) D.getAsmLabel()) { 1782 // The parser guarantees this is a string. 1783 StringLiteral *SE = cast<StringLiteral>(E); 1784 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1785 SE->getByteLength()))); 1786 } 1787 1788 // If name lookup finds a previous declaration that is not in the 1789 // same scope as the new declaration, this may still be an 1790 // acceptable redeclaration. 1791 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1792 !(NewVD->hasLinkage() && 1793 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1794 PrevDecl = 0; 1795 1796 // Merge the decl with the existing one if appropriate. 1797 if (PrevDecl) { 1798 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1799 // The user tried to define a non-static data member 1800 // out-of-line (C++ [dcl.meaning]p1). 1801 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1802 << D.getCXXScopeSpec().getRange(); 1803 PrevDecl = 0; 1804 NewVD->setInvalidDecl(); 1805 } 1806 } else if (D.getCXXScopeSpec().isSet()) { 1807 // No previous declaration in the qualifying scope. 1808 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1809 << Name << D.getCXXScopeSpec().getRange(); 1810 NewVD->setInvalidDecl(); 1811 } 1812 1813 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1814 1815 // If this is a locally-scoped extern C variable, update the map of 1816 // such variables. 1817 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1818 !NewVD->isInvalidDecl()) 1819 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1820 1821 return NewVD; 1822} 1823 1824/// \brief Perform semantic checking on a newly-created variable 1825/// declaration. 1826/// 1827/// This routine performs all of the type-checking required for a 1828/// variable declaration once it has been build. It is used both to 1829/// check variables after they have been parsed and their declarators 1830/// have been translated into a declaration, and to check 1831/// 1832/// Sets NewVD->isInvalidDecl() if an error was encountered. 1833void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1834 bool &Redeclaration) { 1835 // If the decl is already known invalid, don't check it. 1836 if (NewVD->isInvalidDecl()) 1837 return; 1838 1839 QualType T = NewVD->getType(); 1840 1841 if (T->isObjCInterfaceType()) { 1842 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1843 return NewVD->setInvalidDecl(); 1844 } 1845 1846 // The variable can not have an abstract class type. 1847 if (RequireNonAbstractType(NewVD->getLocation(), T, 1848 diag::err_abstract_type_in_decl, 1849 AbstractVariableType)) 1850 return NewVD->setInvalidDecl(); 1851 1852 // Emit an error if an address space was applied to decl with local storage. 1853 // This includes arrays of objects with address space qualifiers, but not 1854 // automatic variables that point to other address spaces. 1855 // ISO/IEC TR 18037 S5.1.2 1856 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1857 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1858 return NewVD->setInvalidDecl(); 1859 } 1860 1861 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1862 && !NewVD->hasAttr<BlocksAttr>()) 1863 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1864 1865 bool isVM = T->isVariablyModifiedType(); 1866 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1867 CurFunctionNeedsScopeChecking = true; 1868 1869 if ((isVM && NewVD->hasLinkage()) || 1870 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1871 bool SizeIsNegative; 1872 QualType FixedTy = 1873 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1874 1875 if (FixedTy.isNull() && T->isVariableArrayType()) { 1876 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1877 // FIXME: This won't give the correct result for 1878 // int a[10][n]; 1879 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1880 1881 if (NewVD->isFileVarDecl()) 1882 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1883 << SizeRange; 1884 else if (NewVD->getStorageClass() == VarDecl::Static) 1885 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1886 << SizeRange; 1887 else 1888 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1889 << SizeRange; 1890 return NewVD->setInvalidDecl(); 1891 } 1892 1893 if (FixedTy.isNull()) { 1894 if (NewVD->isFileVarDecl()) 1895 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1896 else 1897 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1898 return NewVD->setInvalidDecl(); 1899 } 1900 1901 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1902 NewVD->setType(FixedTy); 1903 } 1904 1905 if (!PrevDecl && NewVD->isExternC(Context)) { 1906 // Since we did not find anything by this name and we're declaring 1907 // an extern "C" variable, look for a non-visible extern "C" 1908 // declaration with the same name. 1909 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1910 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1911 if (Pos != LocallyScopedExternalDecls.end()) 1912 PrevDecl = Pos->second; 1913 } 1914 1915 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1916 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1917 << T; 1918 return NewVD->setInvalidDecl(); 1919 } 1920 1921 if (PrevDecl) { 1922 Redeclaration = true; 1923 MergeVarDecl(NewVD, PrevDecl); 1924 } 1925} 1926 1927NamedDecl* 1928Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1929 QualType R, NamedDecl* PrevDecl, 1930 bool IsFunctionDefinition, bool &Redeclaration) { 1931 assert(R.getTypePtr()->isFunctionType()); 1932 1933 DeclarationName Name = GetNameForDeclarator(D); 1934 FunctionDecl::StorageClass SC = FunctionDecl::None; 1935 switch (D.getDeclSpec().getStorageClassSpec()) { 1936 default: assert(0 && "Unknown storage class!"); 1937 case DeclSpec::SCS_auto: 1938 case DeclSpec::SCS_register: 1939 case DeclSpec::SCS_mutable: 1940 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1941 diag::err_typecheck_sclass_func); 1942 D.setInvalidType(); 1943 break; 1944 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1945 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1946 case DeclSpec::SCS_static: { 1947 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1948 // C99 6.7.1p5: 1949 // The declaration of an identifier for a function that has 1950 // block scope shall have no explicit storage-class specifier 1951 // other than extern 1952 // See also (C++ [dcl.stc]p4). 1953 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1954 diag::err_static_block_func); 1955 SC = FunctionDecl::None; 1956 } else 1957 SC = FunctionDecl::Static; 1958 break; 1959 } 1960 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1961 } 1962 1963 if (D.getDeclSpec().isThreadSpecified()) 1964 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1965 1966 bool isInline = D.getDeclSpec().isInlineSpecified(); 1967 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1968 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1969 1970 // Check that the return type is not an abstract class type. 1971 // For record types, this is done by the AbstractClassUsageDiagnoser once 1972 // the class has been completely parsed. 1973 if (!DC->isRecord() && 1974 RequireNonAbstractType(D.getIdentifierLoc(), 1975 R->getAsFunctionType()->getResultType(), 1976 diag::err_abstract_type_in_decl, 1977 AbstractReturnType)) 1978 D.setInvalidType(); 1979 1980 // Do not allow returning a objc interface by-value. 1981 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1982 Diag(D.getIdentifierLoc(), 1983 diag::err_object_cannot_be_passed_returned_by_value) << 0 1984 << R->getAsFunctionType()->getResultType(); 1985 D.setInvalidType(); 1986 } 1987 1988 bool isVirtualOkay = false; 1989 FunctionDecl *NewFD; 1990 if (D.getKind() == Declarator::DK_Constructor) { 1991 // This is a C++ constructor declaration. 1992 assert(DC->isRecord() && 1993 "Constructors can only be declared in a member context"); 1994 1995 R = CheckConstructorDeclarator(D, R, SC); 1996 1997 // Create the new declaration 1998 NewFD = CXXConstructorDecl::Create(Context, 1999 cast<CXXRecordDecl>(DC), 2000 D.getIdentifierLoc(), Name, R, 2001 isExplicit, isInline, 2002 /*isImplicitlyDeclared=*/false); 2003 } else if (D.getKind() == Declarator::DK_Destructor) { 2004 // This is a C++ destructor declaration. 2005 if (DC->isRecord()) { 2006 R = CheckDestructorDeclarator(D, SC); 2007 2008 NewFD = CXXDestructorDecl::Create(Context, 2009 cast<CXXRecordDecl>(DC), 2010 D.getIdentifierLoc(), Name, R, 2011 isInline, 2012 /*isImplicitlyDeclared=*/false); 2013 2014 isVirtualOkay = true; 2015 } else { 2016 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2017 2018 // Create a FunctionDecl to satisfy the function definition parsing 2019 // code path. 2020 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2021 Name, R, SC, isInline, 2022 /*hasPrototype=*/true, 2023 // FIXME: Move to DeclGroup... 2024 D.getDeclSpec().getSourceRange().getBegin()); 2025 D.setInvalidType(); 2026 } 2027 } else if (D.getKind() == Declarator::DK_Conversion) { 2028 if (!DC->isRecord()) { 2029 Diag(D.getIdentifierLoc(), 2030 diag::err_conv_function_not_member); 2031 return 0; 2032 } 2033 2034 CheckConversionDeclarator(D, R, SC); 2035 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2036 D.getIdentifierLoc(), Name, R, 2037 isInline, isExplicit); 2038 2039 isVirtualOkay = true; 2040 } else if (DC->isRecord()) { 2041 // This is a C++ method declaration. 2042 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2043 D.getIdentifierLoc(), Name, R, 2044 (SC == FunctionDecl::Static), isInline); 2045 2046 isVirtualOkay = (SC != FunctionDecl::Static); 2047 } else { 2048 // Determine whether the function was written with a 2049 // prototype. This true when: 2050 // - we're in C++ (where every function has a prototype), 2051 // - there is a prototype in the declarator, or 2052 // - the type R of the function is some kind of typedef or other reference 2053 // to a type name (which eventually refers to a function type). 2054 bool HasPrototype = 2055 getLangOptions().CPlusPlus || 2056 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2057 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2058 2059 NewFD = FunctionDecl::Create(Context, DC, 2060 D.getIdentifierLoc(), 2061 Name, R, SC, isInline, HasPrototype, 2062 // FIXME: Move to DeclGroup... 2063 D.getDeclSpec().getSourceRange().getBegin()); 2064 } 2065 2066 if (D.isInvalidType()) 2067 NewFD->setInvalidDecl(); 2068 2069 // Set the lexical context. If the declarator has a C++ 2070 // scope specifier, the lexical context will be different 2071 // from the semantic context. 2072 NewFD->setLexicalDeclContext(CurContext); 2073 2074 // C++ [dcl.fct.spec]p5: 2075 // The virtual specifier shall only be used in declarations of 2076 // nonstatic class member functions that appear within a 2077 // member-specification of a class declaration; see 10.3. 2078 // 2079 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2080 // function is also virtual if it overrides an already virtual 2081 // function. This is important to do here because it's part of the 2082 // declaration. 2083 if (isVirtual && !NewFD->isInvalidDecl()) { 2084 if (!isVirtualOkay) { 2085 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2086 diag::err_virtual_non_function); 2087 } else if (!CurContext->isRecord()) { 2088 // 'virtual' was specified outside of the class. 2089 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2090 << CodeModificationHint::CreateRemoval( 2091 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2092 } else { 2093 // Okay: Add virtual to the method. 2094 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2095 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2096 CurClass->setAggregate(false); 2097 CurClass->setPOD(false); 2098 CurClass->setPolymorphic(true); 2099 CurClass->setHasTrivialConstructor(false); 2100 } 2101 } 2102 2103 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2104 !CurContext->isRecord()) { 2105 // C++ [class.static]p1: 2106 // A data or function member of a class may be declared static 2107 // in a class definition, in which case it is a static member of 2108 // the class. 2109 2110 // Complain about the 'static' specifier if it's on an out-of-line 2111 // member function definition. 2112 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2113 diag::err_static_out_of_line) 2114 << CodeModificationHint::CreateRemoval( 2115 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2116 } 2117 2118 // Handle GNU asm-label extension (encoded as an attribute). 2119 if (Expr *E = (Expr*) D.getAsmLabel()) { 2120 // The parser guarantees this is a string. 2121 StringLiteral *SE = cast<StringLiteral>(E); 2122 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2123 SE->getByteLength()))); 2124 } 2125 2126 // Copy the parameter declarations from the declarator D to the function 2127 // declaration NewFD, if they are available. First scavenge them into Params. 2128 llvm::SmallVector<ParmVarDecl*, 16> Params; 2129 if (D.getNumTypeObjects() > 0) { 2130 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2131 2132 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2133 // function that takes no arguments, not a function that takes a 2134 // single void argument. 2135 // We let through "const void" here because Sema::GetTypeForDeclarator 2136 // already checks for that case. 2137 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2138 FTI.ArgInfo[0].Param && 2139 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2140 // Empty arg list, don't push any params. 2141 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2142 2143 // In C++, the empty parameter-type-list must be spelled "void"; a 2144 // typedef of void is not permitted. 2145 if (getLangOptions().CPlusPlus && 2146 Param->getType().getUnqualifiedType() != Context.VoidTy) 2147 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2148 // FIXME: Leaks decl? 2149 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2150 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2151 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2152 } 2153 2154 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2155 // When we're declaring a function with a typedef, typeof, etc as in the 2156 // following example, we'll need to synthesize (unnamed) 2157 // parameters for use in the declaration. 2158 // 2159 // @code 2160 // typedef void fn(int); 2161 // fn f; 2162 // @endcode 2163 2164 // Synthesize a parameter for each argument type. 2165 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2166 AE = FT->arg_type_end(); AI != AE; ++AI) { 2167 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2168 SourceLocation(), 0, 2169 *AI, VarDecl::None, 0); 2170 Param->setImplicit(); 2171 Params.push_back(Param); 2172 } 2173 } else { 2174 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2175 "Should not need args for typedef of non-prototype fn"); 2176 } 2177 // Finally, we know we have the right number of parameters, install them. 2178 NewFD->setParams(Context, &Params[0], Params.size()); 2179 2180 2181 2182 // If name lookup finds a previous declaration that is not in the 2183 // same scope as the new declaration, this may still be an 2184 // acceptable redeclaration. 2185 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2186 !(NewFD->hasLinkage() && 2187 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2188 PrevDecl = 0; 2189 2190 // FIXME: We need to determine whether the GNU inline attribute will 2191 // be applied to this function declaration, since it affects 2192 // declaration merging. This hack will go away when the FIXME below 2193 // is resolved, since we should be putting *all* attributes onto the 2194 // declaration now. 2195 for (const AttributeList *Attr = D.getDeclSpec().getAttributes(); 2196 Attr; Attr = Attr->getNext()) { 2197 if (Attr->getKind() == AttributeList::AT_gnu_inline) { 2198 NewFD->addAttr(::new (Context) GNUInlineAttr()); 2199 break; 2200 } 2201 } 2202 2203 // Perform semantic checking on the function declaration. 2204 bool OverloadableAttrRequired = false; // FIXME: HACK! 2205 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2206 /*FIXME:*/OverloadableAttrRequired); 2207 2208 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2209 // An out-of-line member function declaration must also be a 2210 // definition (C++ [dcl.meaning]p1). 2211 if (!IsFunctionDefinition) { 2212 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2213 << D.getCXXScopeSpec().getRange(); 2214 NewFD->setInvalidDecl(); 2215 } else if (!Redeclaration) { 2216 // The user tried to provide an out-of-line definition for a 2217 // function that is a member of a class or namespace, but there 2218 // was no such member function declared (C++ [class.mfct]p2, 2219 // C++ [namespace.memdef]p2). For example: 2220 // 2221 // class X { 2222 // void f() const; 2223 // }; 2224 // 2225 // void X::f() { } // ill-formed 2226 // 2227 // Complain about this problem, and attempt to suggest close 2228 // matches (e.g., those that differ only in cv-qualifiers and 2229 // whether the parameter types are references). 2230 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2231 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2232 NewFD->setInvalidDecl(); 2233 2234 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2235 true); 2236 assert(!Prev.isAmbiguous() && 2237 "Cannot have an ambiguity in previous-declaration lookup"); 2238 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2239 Func != FuncEnd; ++Func) { 2240 if (isa<FunctionDecl>(*Func) && 2241 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2242 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2243 } 2244 2245 PrevDecl = 0; 2246 } 2247 } 2248 2249 // Handle attributes. We need to have merged decls when handling attributes 2250 // (for example to check for conflicts, etc). 2251 // FIXME: This needs to happen before we merge declarations. Then, 2252 // let attribute merging cope with attribute conflicts. 2253 ProcessDeclAttributes(NewFD, D); 2254 AddKnownFunctionAttributes(NewFD); 2255 2256 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2257 // If a function name is overloadable in C, then every function 2258 // with that name must be marked "overloadable". 2259 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2260 << Redeclaration << NewFD; 2261 if (PrevDecl) 2262 Diag(PrevDecl->getLocation(), 2263 diag::note_attribute_overloadable_prev_overload); 2264 NewFD->addAttr(::new (Context) OverloadableAttr()); 2265 } 2266 2267 // If this is a locally-scoped extern C function, update the 2268 // map of such names. 2269 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2270 && !NewFD->isInvalidDecl()) 2271 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2272 2273 return NewFD; 2274} 2275 2276/// \brief Perform semantic checking of a new function declaration. 2277/// 2278/// Performs semantic analysis of the new function declaration 2279/// NewFD. This routine performs all semantic checking that does not 2280/// require the actual declarator involved in the declaration, and is 2281/// used both for the declaration of functions as they are parsed 2282/// (called via ActOnDeclarator) and for the declaration of functions 2283/// that have been instantiated via C++ template instantiation (called 2284/// via InstantiateDecl). 2285/// 2286/// This sets NewFD->isInvalidDecl() to true if there was an error. 2287void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2288 bool &Redeclaration, 2289 bool &OverloadableAttrRequired) { 2290 // If NewFD is already known erroneous, don't do any of this checking. 2291 if (NewFD->isInvalidDecl()) 2292 return; 2293 2294 // Semantic checking for this function declaration (in isolation). 2295 if (getLangOptions().CPlusPlus) { 2296 // C++-specific checks. 2297 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2298 CheckConstructor(Constructor); 2299 } else if (isa<CXXDestructorDecl>(NewFD)) { 2300 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2301 Record->setUserDeclaredDestructor(true); 2302 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2303 // user-defined destructor. 2304 Record->setPOD(false); 2305 2306 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2307 // declared destructor. 2308 Record->setHasTrivialDestructor(false); 2309 } else if (CXXConversionDecl *Conversion 2310 = dyn_cast<CXXConversionDecl>(NewFD)) 2311 ActOnConversionDeclarator(Conversion); 2312 2313 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2314 if (NewFD->isOverloadedOperator() && 2315 CheckOverloadedOperatorDeclaration(NewFD)) 2316 return NewFD->setInvalidDecl(); 2317 } 2318 2319 // C99 6.7.4p6: 2320 // [... ] For a function with external linkage, the following 2321 // restrictions apply: [...] If all of the file scope declarations 2322 // for a function in a translation unit include the inline 2323 // function specifier without extern, then the definition in that 2324 // translation unit is an inline definition. An inline definition 2325 // does not provide an external definition for the function, and 2326 // does not forbid an external definition in another translation 2327 // unit. 2328 // 2329 // Here we determine whether this function, in isolation, would be a 2330 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2331 // previous declarations. 2332 if (NewFD->isInline() && 2333 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2334 bool GNUInline = NewFD->hasAttr<GNUInlineAttr>() || 2335 (PrevDecl && PrevDecl->hasAttr<GNUInlineAttr>()); 2336 if (GNUInline || (!getLangOptions().CPlusPlus && !getLangOptions().C99)) { 2337 // GNU "extern inline" is the same as "inline" in C99. 2338 if (NewFD->getStorageClass() == FunctionDecl::Extern) 2339 NewFD->setC99InlineDefinition(true); 2340 } else if (getLangOptions().C99 && 2341 NewFD->getStorageClass() == FunctionDecl::None) 2342 NewFD->setC99InlineDefinition(true); 2343 } 2344 2345 // Check for a previous declaration of this name. 2346 if (!PrevDecl && NewFD->isExternC(Context)) { 2347 // Since we did not find anything by this name and we're declaring 2348 // an extern "C" function, look for a non-visible extern "C" 2349 // declaration with the same name. 2350 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2351 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2352 if (Pos != LocallyScopedExternalDecls.end()) 2353 PrevDecl = Pos->second; 2354 } 2355 2356 // Merge or overload the declaration with an existing declaration of 2357 // the same name, if appropriate. 2358 if (PrevDecl) { 2359 // Determine whether NewFD is an overload of PrevDecl or 2360 // a declaration that requires merging. If it's an overload, 2361 // there's no more work to do here; we'll just add the new 2362 // function to the scope. 2363 OverloadedFunctionDecl::function_iterator MatchedDecl; 2364 2365 if (!getLangOptions().CPlusPlus && 2366 AllowOverloadingOfFunction(PrevDecl, Context)) { 2367 OverloadableAttrRequired = true; 2368 2369 // Functions marked "overloadable" must have a prototype (that 2370 // we can't get through declaration merging). 2371 if (!NewFD->getType()->getAsFunctionProtoType()) { 2372 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2373 << NewFD; 2374 Redeclaration = true; 2375 2376 // Turn this into a variadic function with no parameters. 2377 QualType R = Context.getFunctionType( 2378 NewFD->getType()->getAsFunctionType()->getResultType(), 2379 0, 0, true, 0); 2380 NewFD->setType(R); 2381 return NewFD->setInvalidDecl(); 2382 } 2383 } 2384 2385 if (PrevDecl && 2386 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2387 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2388 Redeclaration = true; 2389 Decl *OldDecl = PrevDecl; 2390 2391 // If PrevDecl was an overloaded function, extract the 2392 // FunctionDecl that matched. 2393 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2394 OldDecl = *MatchedDecl; 2395 2396 // NewFD and OldDecl represent declarations that need to be 2397 // merged. 2398 if (MergeFunctionDecl(NewFD, OldDecl)) 2399 return NewFD->setInvalidDecl(); 2400 2401 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2402 } 2403 } 2404 2405 // In C++, check default arguments now that we have merged decls. Unless 2406 // the lexical context is the class, because in this case this is done 2407 // during delayed parsing anyway. 2408 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2409 CheckCXXDefaultArguments(NewFD); 2410} 2411 2412bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2413 // FIXME: Need strict checking. In C89, we need to check for 2414 // any assignment, increment, decrement, function-calls, or 2415 // commas outside of a sizeof. In C99, it's the same list, 2416 // except that the aforementioned are allowed in unevaluated 2417 // expressions. Everything else falls under the 2418 // "may accept other forms of constant expressions" exception. 2419 // (We never end up here for C++, so the constant expression 2420 // rules there don't matter.) 2421 if (Init->isConstantInitializer(Context)) 2422 return false; 2423 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2424 << Init->getSourceRange(); 2425 return true; 2426} 2427 2428void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2429 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2430} 2431 2432/// AddInitializerToDecl - Adds the initializer Init to the 2433/// declaration dcl. If DirectInit is true, this is C++ direct 2434/// initialization rather than copy initialization. 2435void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2436 Decl *RealDecl = dcl.getAs<Decl>(); 2437 // If there is no declaration, there was an error parsing it. Just ignore 2438 // the initializer. 2439 if (RealDecl == 0) 2440 return; 2441 2442 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2443 // With declarators parsed the way they are, the parser cannot 2444 // distinguish between a normal initializer and a pure-specifier. 2445 // Thus this grotesque test. 2446 IntegerLiteral *IL; 2447 Expr *Init = static_cast<Expr *>(init.get()); 2448 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2449 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2450 if (Method->isVirtual()) { 2451 Method->setPure(); 2452 2453 // A class is abstract if at least one function is pure virtual. 2454 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2455 } else if (!Method->isInvalidDecl()) { 2456 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2457 << Method->getDeclName() << Init->getSourceRange(); 2458 Method->setInvalidDecl(); 2459 } 2460 } else { 2461 Diag(Method->getLocation(), diag::err_member_function_initialization) 2462 << Method->getDeclName() << Init->getSourceRange(); 2463 Method->setInvalidDecl(); 2464 } 2465 return; 2466 } 2467 2468 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2469 if (!VDecl) { 2470 if (getLangOptions().CPlusPlus && 2471 RealDecl->getLexicalDeclContext()->isRecord() && 2472 isa<NamedDecl>(RealDecl)) 2473 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2474 << cast<NamedDecl>(RealDecl)->getDeclName(); 2475 else 2476 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2477 RealDecl->setInvalidDecl(); 2478 return; 2479 } 2480 2481 if (!VDecl->getType()->isArrayType() && 2482 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2483 diag::err_typecheck_decl_incomplete_type)) { 2484 RealDecl->setInvalidDecl(); 2485 return; 2486 } 2487 2488 const VarDecl *Def = 0; 2489 if (VDecl->getDefinition(Def)) { 2490 Diag(VDecl->getLocation(), diag::err_redefinition) 2491 << VDecl->getDeclName(); 2492 Diag(Def->getLocation(), diag::note_previous_definition); 2493 VDecl->setInvalidDecl(); 2494 return; 2495 } 2496 2497 // Take ownership of the expression, now that we're sure we have somewhere 2498 // to put it. 2499 Expr *Init = static_cast<Expr *>(init.release()); 2500 assert(Init && "missing initializer"); 2501 2502 // Get the decls type and save a reference for later, since 2503 // CheckInitializerTypes may change it. 2504 QualType DclT = VDecl->getType(), SavT = DclT; 2505 if (VDecl->isBlockVarDecl()) { 2506 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2507 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2508 VDecl->setInvalidDecl(); 2509 } else if (!VDecl->isInvalidDecl()) { 2510 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2511 VDecl->getDeclName(), DirectInit)) 2512 VDecl->setInvalidDecl(); 2513 2514 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2515 // Don't check invalid declarations to avoid emitting useless diagnostics. 2516 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2517 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2518 CheckForConstantInitializer(Init, DclT); 2519 } 2520 } 2521 } else if (VDecl->isStaticDataMember() && 2522 VDecl->getLexicalDeclContext()->isRecord()) { 2523 // This is an in-class initialization for a static data member, e.g., 2524 // 2525 // struct S { 2526 // static const int value = 17; 2527 // }; 2528 2529 // Attach the initializer 2530 VDecl->setInit(Init); 2531 2532 // C++ [class.mem]p4: 2533 // A member-declarator can contain a constant-initializer only 2534 // if it declares a static member (9.4) of const integral or 2535 // const enumeration type, see 9.4.2. 2536 QualType T = VDecl->getType(); 2537 if (!T->isDependentType() && 2538 (!Context.getCanonicalType(T).isConstQualified() || 2539 !T->isIntegralType())) { 2540 Diag(VDecl->getLocation(), diag::err_member_initialization) 2541 << VDecl->getDeclName() << Init->getSourceRange(); 2542 VDecl->setInvalidDecl(); 2543 } else { 2544 // C++ [class.static.data]p4: 2545 // If a static data member is of const integral or const 2546 // enumeration type, its declaration in the class definition 2547 // can specify a constant-initializer which shall be an 2548 // integral constant expression (5.19). 2549 if (!Init->isTypeDependent() && 2550 !Init->getType()->isIntegralType()) { 2551 // We have a non-dependent, non-integral or enumeration type. 2552 Diag(Init->getSourceRange().getBegin(), 2553 diag::err_in_class_initializer_non_integral_type) 2554 << Init->getType() << Init->getSourceRange(); 2555 VDecl->setInvalidDecl(); 2556 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2557 // Check whether the expression is a constant expression. 2558 llvm::APSInt Value; 2559 SourceLocation Loc; 2560 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2561 Diag(Loc, diag::err_in_class_initializer_non_constant) 2562 << Init->getSourceRange(); 2563 VDecl->setInvalidDecl(); 2564 } else if (!VDecl->getType()->isDependentType()) 2565 ImpCastExprToType(Init, VDecl->getType()); 2566 } 2567 } 2568 } else if (VDecl->isFileVarDecl()) { 2569 if (VDecl->getStorageClass() == VarDecl::Extern) 2570 Diag(VDecl->getLocation(), diag::warn_extern_init); 2571 if (!VDecl->isInvalidDecl()) 2572 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2573 VDecl->getDeclName(), DirectInit)) 2574 VDecl->setInvalidDecl(); 2575 2576 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2577 // Don't check invalid declarations to avoid emitting useless diagnostics. 2578 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2579 // C99 6.7.8p4. All file scoped initializers need to be constant. 2580 CheckForConstantInitializer(Init, DclT); 2581 } 2582 } 2583 // If the type changed, it means we had an incomplete type that was 2584 // completed by the initializer. For example: 2585 // int ary[] = { 1, 3, 5 }; 2586 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2587 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2588 VDecl->setType(DclT); 2589 Init->setType(DclT); 2590 } 2591 2592 // Attach the initializer to the decl. 2593 VDecl->setInit(Init); 2594 2595 // If the previous declaration of VDecl was a tentative definition, 2596 // remove it from the set of tentative definitions. 2597 if (VDecl->getPreviousDeclaration() && 2598 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2599 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2600 = TentativeDefinitions.find(VDecl->getDeclName()); 2601 assert(Pos != TentativeDefinitions.end() && 2602 "Unrecorded tentative definition?"); 2603 TentativeDefinitions.erase(Pos); 2604 } 2605 2606 return; 2607} 2608 2609void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2610 Decl *RealDecl = dcl.getAs<Decl>(); 2611 2612 // If there is no declaration, there was an error parsing it. Just ignore it. 2613 if (RealDecl == 0) 2614 return; 2615 2616 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2617 QualType Type = Var->getType(); 2618 2619 // Record tentative definitions. 2620 if (Var->isTentativeDefinition(Context)) 2621 TentativeDefinitions[Var->getDeclName()] = Var; 2622 2623 // C++ [dcl.init.ref]p3: 2624 // The initializer can be omitted for a reference only in a 2625 // parameter declaration (8.3.5), in the declaration of a 2626 // function return type, in the declaration of a class member 2627 // within its class declaration (9.2), and where the extern 2628 // specifier is explicitly used. 2629 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2630 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2631 << Var->getDeclName() 2632 << SourceRange(Var->getLocation(), Var->getLocation()); 2633 Var->setInvalidDecl(); 2634 return; 2635 } 2636 2637 // C++ [dcl.init]p9: 2638 // 2639 // If no initializer is specified for an object, and the object 2640 // is of (possibly cv-qualified) non-POD class type (or array 2641 // thereof), the object shall be default-initialized; if the 2642 // object is of const-qualified type, the underlying class type 2643 // shall have a user-declared default constructor. 2644 if (getLangOptions().CPlusPlus) { 2645 QualType InitType = Type; 2646 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2647 InitType = Array->getElementType(); 2648 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2649 CXXRecordDecl *RD = 2650 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2651 CXXConstructorDecl *Constructor = 0; 2652 if (!RequireCompleteType(Var->getLocation(), InitType, 2653 diag::err_invalid_incomplete_type_use)) 2654 Constructor 2655 = PerformInitializationByConstructor(InitType, 0, 0, 2656 Var->getLocation(), 2657 SourceRange(Var->getLocation(), 2658 Var->getLocation()), 2659 Var->getDeclName(), 2660 IK_Default); 2661 if (!Constructor) 2662 Var->setInvalidDecl(); 2663 else if (!RD->hasTrivialConstructor()) 2664 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2665 } 2666 } 2667 2668#if 0 2669 // FIXME: Temporarily disabled because we are not properly parsing 2670 // linkage specifications on declarations, e.g., 2671 // 2672 // extern "C" const CGPoint CGPointerZero; 2673 // 2674 // C++ [dcl.init]p9: 2675 // 2676 // If no initializer is specified for an object, and the 2677 // object is of (possibly cv-qualified) non-POD class type (or 2678 // array thereof), the object shall be default-initialized; if 2679 // the object is of const-qualified type, the underlying class 2680 // type shall have a user-declared default 2681 // constructor. Otherwise, if no initializer is specified for 2682 // an object, the object and its subobjects, if any, have an 2683 // indeterminate initial value; if the object or any of its 2684 // subobjects are of const-qualified type, the program is 2685 // ill-formed. 2686 // 2687 // This isn't technically an error in C, so we don't diagnose it. 2688 // 2689 // FIXME: Actually perform the POD/user-defined default 2690 // constructor check. 2691 if (getLangOptions().CPlusPlus && 2692 Context.getCanonicalType(Type).isConstQualified() && 2693 !Var->hasExternalStorage()) 2694 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2695 << Var->getName() 2696 << SourceRange(Var->getLocation(), Var->getLocation()); 2697#endif 2698 } 2699} 2700 2701Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2702 unsigned NumDecls) { 2703 llvm::SmallVector<Decl*, 8> Decls; 2704 2705 for (unsigned i = 0; i != NumDecls; ++i) 2706 if (Decl *D = Group[i].getAs<Decl>()) 2707 Decls.push_back(D); 2708 2709 // Perform semantic analysis that depends on having fully processed both 2710 // the declarator and initializer. 2711 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2712 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2713 if (!IDecl) 2714 continue; 2715 QualType T = IDecl->getType(); 2716 2717 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2718 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2719 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2720 if (!IDecl->isInvalidDecl() && 2721 RequireCompleteType(IDecl->getLocation(), T, 2722 diag::err_typecheck_decl_incomplete_type)) 2723 IDecl->setInvalidDecl(); 2724 } 2725 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2726 // object that has file scope without an initializer, and without a 2727 // storage-class specifier or with the storage-class specifier "static", 2728 // constitutes a tentative definition. Note: A tentative definition with 2729 // external linkage is valid (C99 6.2.2p5). 2730 if (IDecl->isTentativeDefinition(Context)) { 2731 QualType CheckType = T; 2732 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2733 2734 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2735 if (ArrayT) { 2736 CheckType = ArrayT->getElementType(); 2737 DiagID = diag::err_illegal_decl_array_incomplete_type; 2738 } 2739 2740 if (IDecl->isInvalidDecl()) { 2741 // Do nothing with invalid declarations 2742 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2743 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2744 // C99 6.9.2p3: If the declaration of an identifier for an object is 2745 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2746 // declared type shall not be an incomplete type. 2747 IDecl->setInvalidDecl(); 2748 } 2749 } 2750 } 2751 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2752 &Decls[0], Decls.size())); 2753} 2754 2755 2756/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2757/// to introduce parameters into function prototype scope. 2758Sema::DeclPtrTy 2759Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2760 const DeclSpec &DS = D.getDeclSpec(); 2761 2762 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2763 VarDecl::StorageClass StorageClass = VarDecl::None; 2764 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2765 StorageClass = VarDecl::Register; 2766 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2767 Diag(DS.getStorageClassSpecLoc(), 2768 diag::err_invalid_storage_class_in_func_decl); 2769 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2770 } 2771 2772 if (D.getDeclSpec().isThreadSpecified()) 2773 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2774 2775 DiagnoseFunctionSpecifiers(D); 2776 2777 // Check that there are no default arguments inside the type of this 2778 // parameter (C++ only). 2779 if (getLangOptions().CPlusPlus) 2780 CheckExtraCXXDefaultArguments(D); 2781 2782 QualType parmDeclType = GetTypeForDeclarator(D, S); 2783 2784 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2785 // Can this happen for params? We already checked that they don't conflict 2786 // among each other. Here they can only shadow globals, which is ok. 2787 IdentifierInfo *II = D.getIdentifier(); 2788 if (II) { 2789 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2790 if (PrevDecl->isTemplateParameter()) { 2791 // Maybe we will complain about the shadowed template parameter. 2792 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2793 // Just pretend that we didn't see the previous declaration. 2794 PrevDecl = 0; 2795 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2796 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2797 2798 // Recover by removing the name 2799 II = 0; 2800 D.SetIdentifier(0, D.getIdentifierLoc()); 2801 } 2802 } 2803 } 2804 2805 // Parameters can not be abstract class types. 2806 // For record types, this is done by the AbstractClassUsageDiagnoser once 2807 // the class has been completely parsed. 2808 if (!CurContext->isRecord() && 2809 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2810 diag::err_abstract_type_in_decl, 2811 AbstractParamType)) 2812 D.setInvalidType(true); 2813 2814 QualType T = adjustParameterType(parmDeclType); 2815 2816 ParmVarDecl *New; 2817 if (T == parmDeclType) // parameter type did not need adjustment 2818 New = ParmVarDecl::Create(Context, CurContext, 2819 D.getIdentifierLoc(), II, 2820 parmDeclType, StorageClass, 2821 0); 2822 else // keep track of both the adjusted and unadjusted types 2823 New = OriginalParmVarDecl::Create(Context, CurContext, 2824 D.getIdentifierLoc(), II, T, 2825 parmDeclType, StorageClass, 0); 2826 2827 if (D.isInvalidType()) 2828 New->setInvalidDecl(); 2829 2830 // Parameter declarators cannot be interface types. All ObjC objects are 2831 // passed by reference. 2832 if (T->isObjCInterfaceType()) { 2833 Diag(D.getIdentifierLoc(), 2834 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2835 New->setInvalidDecl(); 2836 } 2837 2838 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2839 if (D.getCXXScopeSpec().isSet()) { 2840 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2841 << D.getCXXScopeSpec().getRange(); 2842 New->setInvalidDecl(); 2843 } 2844 2845 // Add the parameter declaration into this scope. 2846 S->AddDecl(DeclPtrTy::make(New)); 2847 if (II) 2848 IdResolver.AddDecl(New); 2849 2850 ProcessDeclAttributes(New, D); 2851 return DeclPtrTy::make(New); 2852} 2853 2854void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2855 SourceLocation LocAfterDecls) { 2856 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2857 "Not a function declarator!"); 2858 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2859 2860 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2861 // for a K&R function. 2862 if (!FTI.hasPrototype) { 2863 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2864 --i; 2865 if (FTI.ArgInfo[i].Param == 0) { 2866 std::string Code = " int "; 2867 Code += FTI.ArgInfo[i].Ident->getName(); 2868 Code += ";\n"; 2869 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2870 << FTI.ArgInfo[i].Ident 2871 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2872 2873 // Implicitly declare the argument as type 'int' for lack of a better 2874 // type. 2875 DeclSpec DS; 2876 const char* PrevSpec; // unused 2877 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2878 PrevSpec); 2879 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2880 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2881 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2882 } 2883 } 2884 } 2885} 2886 2887Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2888 Declarator &D) { 2889 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2890 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2891 "Not a function declarator!"); 2892 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2893 2894 if (FTI.hasPrototype) { 2895 // FIXME: Diagnose arguments without names in C. 2896 } 2897 2898 Scope *ParentScope = FnBodyScope->getParent(); 2899 2900 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2901 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2902} 2903 2904Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2905 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2906 2907 CurFunctionNeedsScopeChecking = false; 2908 2909 // See if this is a redefinition. 2910 const FunctionDecl *Definition; 2911 if (FD->getBody(Context, Definition)) { 2912 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2913 Diag(Definition->getLocation(), diag::note_previous_definition); 2914 } 2915 2916 // Builtin functions cannot be defined. 2917 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2918 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2919 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2920 FD->setInvalidDecl(); 2921 } 2922 } 2923 2924 // The return type of a function definition must be complete 2925 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2926 QualType ResultType = FD->getResultType(); 2927 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2928 RequireCompleteType(FD->getLocation(), ResultType, 2929 diag::err_func_def_incomplete_result)) 2930 FD->setInvalidDecl(); 2931 2932 // GNU warning -Wmissing-prototypes: 2933 // Warn if a global function is defined without a previous 2934 // prototype declaration. This warning is issued even if the 2935 // definition itself provides a prototype. The aim is to detect 2936 // global functions that fail to be declared in header files. 2937 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2938 !FD->isMain()) { 2939 bool MissingPrototype = true; 2940 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2941 Prev; Prev = Prev->getPreviousDeclaration()) { 2942 // Ignore any declarations that occur in function or method 2943 // scope, because they aren't visible from the header. 2944 if (Prev->getDeclContext()->isFunctionOrMethod()) 2945 continue; 2946 2947 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2948 break; 2949 } 2950 2951 if (MissingPrototype) 2952 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2953 } 2954 2955 PushDeclContext(FnBodyScope, FD); 2956 2957 // Check the validity of our function parameters 2958 CheckParmsForFunctionDef(FD); 2959 2960 // Introduce our parameters into the function scope 2961 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2962 ParmVarDecl *Param = FD->getParamDecl(p); 2963 Param->setOwningFunction(FD); 2964 2965 // If this has an identifier, add it to the scope stack. 2966 if (Param->getIdentifier()) 2967 PushOnScopeChains(Param, FnBodyScope); 2968 } 2969 2970 // Checking attributes of current function definition 2971 // dllimport attribute. 2972 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2973 // dllimport attribute cannot be applied to definition. 2974 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2975 Diag(FD->getLocation(), 2976 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2977 << "dllimport"; 2978 FD->setInvalidDecl(); 2979 return DeclPtrTy::make(FD); 2980 } else { 2981 // If a symbol previously declared dllimport is later defined, the 2982 // attribute is ignored in subsequent references, and a warning is 2983 // emitted. 2984 Diag(FD->getLocation(), 2985 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2986 << FD->getNameAsCString() << "dllimport"; 2987 } 2988 } 2989 return DeclPtrTy::make(FD); 2990} 2991 2992 2993Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 2994 Decl *dcl = D.getAs<Decl>(); 2995 Stmt *Body = BodyArg.takeAs<Stmt>(); 2996 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2997 FD->setBody(Body); 2998 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2999 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3000 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3001 MD->setBody(Body); 3002 } else { 3003 Body->Destroy(Context); 3004 return DeclPtrTy(); 3005 } 3006 PopDeclContext(); 3007 // Verify and clean out per-function state. 3008 3009 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3010 3011 // Check goto/label use. 3012 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3013 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3014 LabelStmt *L = I->second; 3015 3016 // Verify that we have no forward references left. If so, there was a goto 3017 // or address of a label taken, but no definition of it. Label fwd 3018 // definitions are indicated with a null substmt. 3019 if (L->getSubStmt() != 0) 3020 continue; 3021 3022 // Emit error. 3023 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3024 3025 // At this point, we have gotos that use the bogus label. Stitch it into 3026 // the function body so that they aren't leaked and that the AST is well 3027 // formed. 3028 if (Body == 0) { 3029 // The whole function wasn't parsed correctly, just delete this. 3030 L->Destroy(Context); 3031 continue; 3032 } 3033 3034 // Otherwise, the body is valid: we want to stitch the label decl into the 3035 // function somewhere so that it is properly owned and so that the goto 3036 // has a valid target. Do this by creating a new compound stmt with the 3037 // label in it. 3038 3039 // Give the label a sub-statement. 3040 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3041 3042 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3043 cast<CXXTryStmt>(Body)->getTryBlock() : 3044 cast<CompoundStmt>(Body); 3045 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3046 Elements.push_back(L); 3047 Compound->setStmts(Context, &Elements[0], Elements.size()); 3048 } 3049 FunctionLabelMap.clear(); 3050 3051 if (!Body) return D; 3052 3053 // Verify that that gotos and switch cases don't jump into scopes illegally. 3054 if (CurFunctionNeedsScopeChecking) 3055 DiagnoseInvalidJumps(Body); 3056 3057 return D; 3058} 3059 3060/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3061/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3062NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3063 IdentifierInfo &II, Scope *S) { 3064 // Before we produce a declaration for an implicitly defined 3065 // function, see whether there was a locally-scoped declaration of 3066 // this name as a function or variable. If so, use that 3067 // (non-visible) declaration, and complain about it. 3068 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3069 = LocallyScopedExternalDecls.find(&II); 3070 if (Pos != LocallyScopedExternalDecls.end()) { 3071 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3072 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3073 return Pos->second; 3074 } 3075 3076 // Extension in C99. Legal in C90, but warn about it. 3077 if (getLangOptions().C99) 3078 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3079 else 3080 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3081 3082 // FIXME: handle stuff like: 3083 // void foo() { extern float X(); } 3084 // void bar() { X(); } <-- implicit decl for X in another scope. 3085 3086 // Set a Declarator for the implicit definition: int foo(); 3087 const char *Dummy; 3088 DeclSpec DS; 3089 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3090 Error = Error; // Silence warning. 3091 assert(!Error && "Error setting up implicit decl!"); 3092 Declarator D(DS, Declarator::BlockContext); 3093 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3094 0, 0, 0, Loc, D), 3095 SourceLocation()); 3096 D.SetIdentifier(&II, Loc); 3097 3098 // Insert this function into translation-unit scope. 3099 3100 DeclContext *PrevDC = CurContext; 3101 CurContext = Context.getTranslationUnitDecl(); 3102 3103 FunctionDecl *FD = 3104 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3105 FD->setImplicit(); 3106 3107 CurContext = PrevDC; 3108 3109 AddKnownFunctionAttributes(FD); 3110 3111 return FD; 3112} 3113 3114/// \brief Adds any function attributes that we know a priori based on 3115/// the declaration of this function. 3116/// 3117/// These attributes can apply both to implicitly-declared builtins 3118/// (like __builtin___printf_chk) or to library-declared functions 3119/// like NSLog or printf. 3120void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3121 if (FD->isInvalidDecl()) 3122 return; 3123 3124 // If this is a built-in function, map its builtin attributes to 3125 // actual attributes. 3126 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3127 // Handle printf-formatting attributes. 3128 unsigned FormatIdx; 3129 bool HasVAListArg; 3130 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3131 if (!FD->getAttr<FormatAttr>()) 3132 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3133 FormatIdx + 2)); 3134 } 3135 3136 // Mark const if we don't care about errno and that is the only 3137 // thing preventing the function from being const. This allows 3138 // IRgen to use LLVM intrinsics for such functions. 3139 if (!getLangOptions().MathErrno && 3140 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3141 if (!FD->getAttr<ConstAttr>()) 3142 FD->addAttr(::new (Context) ConstAttr()); 3143 } 3144 } 3145 3146 IdentifierInfo *Name = FD->getIdentifier(); 3147 if (!Name) 3148 return; 3149 if ((!getLangOptions().CPlusPlus && 3150 FD->getDeclContext()->isTranslationUnit()) || 3151 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3152 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3153 LinkageSpecDecl::lang_c)) { 3154 // Okay: this could be a libc/libm/Objective-C function we know 3155 // about. 3156 } else 3157 return; 3158 3159 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3160 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3161 // FIXME: We known better than our headers. 3162 const_cast<FormatAttr *>(Format)->setType("printf"); 3163 } else 3164 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3165 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3166 if (!FD->getAttr<FormatAttr>()) 3167 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3168 } 3169} 3170 3171TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3172 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3173 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3174 3175 // Scope manipulation handled by caller. 3176 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3177 D.getIdentifierLoc(), 3178 D.getIdentifier(), 3179 T); 3180 3181 if (TagType *TT = dyn_cast<TagType>(T)) { 3182 TagDecl *TD = TT->getDecl(); 3183 3184 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3185 // keep track of the TypedefDecl. 3186 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3187 TD->setTypedefForAnonDecl(NewTD); 3188 } 3189 3190 if (D.isInvalidType()) 3191 NewTD->setInvalidDecl(); 3192 return NewTD; 3193} 3194 3195/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3196/// former case, Name will be non-null. In the later case, Name will be null. 3197/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3198/// reference/declaration/definition of a tag. 3199Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3200 SourceLocation KWLoc, const CXXScopeSpec &SS, 3201 IdentifierInfo *Name, SourceLocation NameLoc, 3202 AttributeList *Attr, AccessSpecifier AS) { 3203 // If this is not a definition, it must have a name. 3204 assert((Name != 0 || TK == TK_Definition) && 3205 "Nameless record must be a definition!"); 3206 3207 TagDecl::TagKind Kind; 3208 switch (TagSpec) { 3209 default: assert(0 && "Unknown tag type!"); 3210 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3211 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3212 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3213 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3214 } 3215 3216 DeclContext *SearchDC = CurContext; 3217 DeclContext *DC = CurContext; 3218 NamedDecl *PrevDecl = 0; 3219 3220 bool Invalid = false; 3221 3222 if (Name && SS.isNotEmpty()) { 3223 // We have a nested-name tag ('struct foo::bar'). 3224 3225 // Check for invalid 'foo::'. 3226 if (SS.isInvalid()) { 3227 Name = 0; 3228 goto CreateNewDecl; 3229 } 3230 3231 // FIXME: RequireCompleteDeclContext(SS)? 3232 DC = computeDeclContext(SS); 3233 SearchDC = DC; 3234 // Look-up name inside 'foo::'. 3235 PrevDecl = dyn_cast_or_null<TagDecl>( 3236 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3237 3238 // A tag 'foo::bar' must already exist. 3239 if (PrevDecl == 0) { 3240 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3241 Name = 0; 3242 goto CreateNewDecl; 3243 } 3244 } else if (Name) { 3245 // If this is a named struct, check to see if there was a previous forward 3246 // declaration or definition. 3247 // FIXME: We're looking into outer scopes here, even when we 3248 // shouldn't be. Doing so can result in ambiguities that we 3249 // shouldn't be diagnosing. 3250 LookupResult R = LookupName(S, Name, LookupTagName, 3251 /*RedeclarationOnly=*/(TK != TK_Reference)); 3252 if (R.isAmbiguous()) { 3253 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3254 // FIXME: This is not best way to recover from case like: 3255 // 3256 // struct S s; 3257 // 3258 // causes needless "incomplete type" error later. 3259 Name = 0; 3260 PrevDecl = 0; 3261 Invalid = true; 3262 } 3263 else 3264 PrevDecl = R; 3265 3266 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3267 // FIXME: This makes sure that we ignore the contexts associated 3268 // with C structs, unions, and enums when looking for a matching 3269 // tag declaration or definition. See the similar lookup tweak 3270 // in Sema::LookupName; is there a better way to deal with this? 3271 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3272 SearchDC = SearchDC->getParent(); 3273 } 3274 } 3275 3276 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3277 // Maybe we will complain about the shadowed template parameter. 3278 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3279 // Just pretend that we didn't see the previous declaration. 3280 PrevDecl = 0; 3281 } 3282 3283 if (PrevDecl) { 3284 // Check whether the previous declaration is usable. 3285 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3286 3287 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3288 // If this is a use of a previous tag, or if the tag is already declared 3289 // in the same scope (so that the definition/declaration completes or 3290 // rementions the tag), reuse the decl. 3291 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3292 // Make sure that this wasn't declared as an enum and now used as a 3293 // struct or something similar. 3294 if (PrevTagDecl->getTagKind() != Kind) { 3295 bool SafeToContinue 3296 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3297 Kind != TagDecl::TK_enum); 3298 if (SafeToContinue) 3299 Diag(KWLoc, diag::err_use_with_wrong_tag) 3300 << Name 3301 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3302 PrevTagDecl->getKindName()); 3303 else 3304 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3305 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3306 3307 if (SafeToContinue) 3308 Kind = PrevTagDecl->getTagKind(); 3309 else { 3310 // Recover by making this an anonymous redefinition. 3311 Name = 0; 3312 PrevDecl = 0; 3313 Invalid = true; 3314 } 3315 } 3316 3317 if (!Invalid) { 3318 // If this is a use, just return the declaration we found. 3319 3320 // FIXME: In the future, return a variant or some other clue 3321 // for the consumer of this Decl to know it doesn't own it. 3322 // For our current ASTs this shouldn't be a problem, but will 3323 // need to be changed with DeclGroups. 3324 if (TK == TK_Reference) 3325 return DeclPtrTy::make(PrevDecl); 3326 3327 // Diagnose attempts to redefine a tag. 3328 if (TK == TK_Definition) { 3329 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3330 Diag(NameLoc, diag::err_redefinition) << Name; 3331 Diag(Def->getLocation(), diag::note_previous_definition); 3332 // If this is a redefinition, recover by making this 3333 // struct be anonymous, which will make any later 3334 // references get the previous definition. 3335 Name = 0; 3336 PrevDecl = 0; 3337 Invalid = true; 3338 } else { 3339 // If the type is currently being defined, complain 3340 // about a nested redefinition. 3341 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3342 if (Tag->isBeingDefined()) { 3343 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3344 Diag(PrevTagDecl->getLocation(), 3345 diag::note_previous_definition); 3346 Name = 0; 3347 PrevDecl = 0; 3348 Invalid = true; 3349 } 3350 } 3351 3352 // Okay, this is definition of a previously declared or referenced 3353 // tag PrevDecl. We're going to create a new Decl for it. 3354 } 3355 } 3356 // If we get here we have (another) forward declaration or we 3357 // have a definition. Just create a new decl. 3358 } else { 3359 // If we get here, this is a definition of a new tag type in a nested 3360 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3361 // new decl/type. We set PrevDecl to NULL so that the entities 3362 // have distinct types. 3363 PrevDecl = 0; 3364 } 3365 // If we get here, we're going to create a new Decl. If PrevDecl 3366 // is non-NULL, it's a definition of the tag declared by 3367 // PrevDecl. If it's NULL, we have a new definition. 3368 } else { 3369 // PrevDecl is a namespace, template, or anything else 3370 // that lives in the IDNS_Tag identifier namespace. 3371 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3372 // The tag name clashes with a namespace name, issue an error and 3373 // recover by making this tag be anonymous. 3374 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3375 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3376 Name = 0; 3377 PrevDecl = 0; 3378 Invalid = true; 3379 } else { 3380 // The existing declaration isn't relevant to us; we're in a 3381 // new scope, so clear out the previous declaration. 3382 PrevDecl = 0; 3383 } 3384 } 3385 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3386 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3387 // C.scope.pdecl]p5: 3388 // -- for an elaborated-type-specifier of the form 3389 // 3390 // class-key identifier 3391 // 3392 // if the elaborated-type-specifier is used in the 3393 // decl-specifier-seq or parameter-declaration-clause of a 3394 // function defined in namespace scope, the identifier is 3395 // declared as a class-name in the namespace that contains 3396 // the declaration; otherwise, except as a friend 3397 // declaration, the identifier is declared in the smallest 3398 // non-class, non-function-prototype scope that contains the 3399 // declaration. 3400 // 3401 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3402 // C structs and unions. 3403 // 3404 // GNU C also supports this behavior as part of its incomplete 3405 // enum types extension, while GNU C++ does not. 3406 // 3407 // Find the context where we'll be declaring the tag. 3408 // FIXME: We would like to maintain the current DeclContext as the 3409 // lexical context, 3410 while (SearchDC->isRecord()) 3411 SearchDC = SearchDC->getParent(); 3412 3413 // Find the scope where we'll be declaring the tag. 3414 while (S->isClassScope() || 3415 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3416 ((S->getFlags() & Scope::DeclScope) == 0) || 3417 (S->getEntity() && 3418 ((DeclContext *)S->getEntity())->isTransparentContext())) 3419 S = S->getParent(); 3420 } 3421 3422CreateNewDecl: 3423 3424 // If there is an identifier, use the location of the identifier as the 3425 // location of the decl, otherwise use the location of the struct/union 3426 // keyword. 3427 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3428 3429 // Otherwise, create a new declaration. If there is a previous 3430 // declaration of the same entity, the two will be linked via 3431 // PrevDecl. 3432 TagDecl *New; 3433 3434 if (Kind == TagDecl::TK_enum) { 3435 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3436 // enum X { A, B, C } D; D should chain to X. 3437 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3438 cast_or_null<EnumDecl>(PrevDecl)); 3439 // If this is an undefined enum, warn. 3440 if (TK != TK_Definition && !Invalid) { 3441 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3442 : diag::ext_forward_ref_enum; 3443 Diag(Loc, DK); 3444 } 3445 } else { 3446 // struct/union/class 3447 3448 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3449 // struct X { int A; } D; D should chain to X. 3450 if (getLangOptions().CPlusPlus) 3451 // FIXME: Look for a way to use RecordDecl for simple structs. 3452 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3453 cast_or_null<CXXRecordDecl>(PrevDecl)); 3454 else 3455 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3456 cast_or_null<RecordDecl>(PrevDecl)); 3457 } 3458 3459 if (Kind != TagDecl::TK_enum) { 3460 // Handle #pragma pack: if the #pragma pack stack has non-default 3461 // alignment, make up a packed attribute for this decl. These 3462 // attributes are checked when the ASTContext lays out the 3463 // structure. 3464 // 3465 // It is important for implementing the correct semantics that this 3466 // happen here (in act on tag decl). The #pragma pack stack is 3467 // maintained as a result of parser callbacks which can occur at 3468 // many points during the parsing of a struct declaration (because 3469 // the #pragma tokens are effectively skipped over during the 3470 // parsing of the struct). 3471 if (unsigned Alignment = getPragmaPackAlignment()) 3472 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3473 } 3474 3475 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3476 // C++ [dcl.typedef]p3: 3477 // [...] Similarly, in a given scope, a class or enumeration 3478 // shall not be declared with the same name as a typedef-name 3479 // that is declared in that scope and refers to a type other 3480 // than the class or enumeration itself. 3481 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3482 TypedefDecl *PrevTypedef = 0; 3483 if (Lookup.getKind() == LookupResult::Found) 3484 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3485 3486 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3487 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3488 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3489 Diag(Loc, diag::err_tag_definition_of_typedef) 3490 << Context.getTypeDeclType(New) 3491 << PrevTypedef->getUnderlyingType(); 3492 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3493 Invalid = true; 3494 } 3495 } 3496 3497 if (Invalid) 3498 New->setInvalidDecl(); 3499 3500 if (Attr) 3501 ProcessDeclAttributeList(New, Attr); 3502 3503 // If we're declaring or defining a tag in function prototype scope 3504 // in C, note that this type can only be used within the function. 3505 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3506 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3507 3508 // Set the lexical context. If the tag has a C++ scope specifier, the 3509 // lexical context will be different from the semantic context. 3510 New->setLexicalDeclContext(CurContext); 3511 3512 // Set the access specifier. 3513 SetMemberAccessSpecifier(New, PrevDecl, AS); 3514 3515 if (TK == TK_Definition) 3516 New->startDefinition(); 3517 3518 // If this has an identifier, add it to the scope stack. 3519 if (Name) { 3520 S = getNonFieldDeclScope(S); 3521 PushOnScopeChains(New, S); 3522 } else { 3523 CurContext->addDecl(Context, New); 3524 } 3525 3526 return DeclPtrTy::make(New); 3527} 3528 3529void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3530 AdjustDeclIfTemplate(TagD); 3531 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3532 3533 // Enter the tag context. 3534 PushDeclContext(S, Tag); 3535 3536 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3537 FieldCollector->StartClass(); 3538 3539 if (Record->getIdentifier()) { 3540 // C++ [class]p2: 3541 // [...] The class-name is also inserted into the scope of the 3542 // class itself; this is known as the injected-class-name. For 3543 // purposes of access checking, the injected-class-name is treated 3544 // as if it were a public member name. 3545 CXXRecordDecl *InjectedClassName 3546 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3547 CurContext, Record->getLocation(), 3548 Record->getIdentifier(), Record); 3549 InjectedClassName->setImplicit(); 3550 InjectedClassName->setAccess(AS_public); 3551 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3552 InjectedClassName->setDescribedClassTemplate(Template); 3553 PushOnScopeChains(InjectedClassName, S); 3554 assert(InjectedClassName->isInjectedClassName() && 3555 "Broken injected-class-name"); 3556 } 3557 } 3558} 3559 3560void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3561 AdjustDeclIfTemplate(TagD); 3562 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3563 3564 if (isa<CXXRecordDecl>(Tag)) 3565 FieldCollector->FinishClass(); 3566 3567 // Exit this scope of this tag's definition. 3568 PopDeclContext(); 3569 3570 // Notify the consumer that we've defined a tag. 3571 Consumer.HandleTagDeclDefinition(Tag); 3572} 3573 3574// Note that FieldName may be null for anonymous bitfields. 3575bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3576 QualType FieldTy, const Expr *BitWidth) { 3577 3578 // C99 6.7.2.1p4 - verify the field type. 3579 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3580 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3581 // Handle incomplete types with specific error. 3582 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3583 return true; 3584 if (FieldName) 3585 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3586 << FieldName << FieldTy << BitWidth->getSourceRange(); 3587 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3588 << FieldTy << BitWidth->getSourceRange(); 3589 } 3590 3591 // If the bit-width is type- or value-dependent, don't try to check 3592 // it now. 3593 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3594 return false; 3595 3596 llvm::APSInt Value; 3597 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3598 return true; 3599 3600 // Zero-width bitfield is ok for anonymous field. 3601 if (Value == 0 && FieldName) 3602 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3603 3604 if (Value.isSigned() && Value.isNegative()) { 3605 if (FieldName) 3606 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3607 << FieldName << Value.toString(10); 3608 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3609 << Value.toString(10); 3610 } 3611 3612 if (!FieldTy->isDependentType()) { 3613 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3614 if (Value.getZExtValue() > TypeSize) { 3615 if (FieldName) 3616 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3617 << FieldName << (unsigned)TypeSize; 3618 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3619 << (unsigned)TypeSize; 3620 } 3621 } 3622 3623 return false; 3624} 3625 3626/// ActOnField - Each field of a struct/union/class is passed into this in order 3627/// to create a FieldDecl object for it. 3628Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3629 SourceLocation DeclStart, 3630 Declarator &D, ExprTy *BitfieldWidth) { 3631 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3632 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3633 AS_public); 3634 return DeclPtrTy::make(Res); 3635} 3636 3637/// HandleField - Analyze a field of a C struct or a C++ data member. 3638/// 3639FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3640 SourceLocation DeclStart, 3641 Declarator &D, Expr *BitWidth, 3642 AccessSpecifier AS) { 3643 IdentifierInfo *II = D.getIdentifier(); 3644 SourceLocation Loc = DeclStart; 3645 if (II) Loc = D.getIdentifierLoc(); 3646 3647 QualType T = GetTypeForDeclarator(D, S); 3648 if (getLangOptions().CPlusPlus) 3649 CheckExtraCXXDefaultArguments(D); 3650 3651 DiagnoseFunctionSpecifiers(D); 3652 3653 if (D.getDeclSpec().isThreadSpecified()) 3654 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3655 3656 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3657 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3658 PrevDecl = 0; 3659 3660 FieldDecl *NewFD 3661 = CheckFieldDecl(II, T, Record, Loc, 3662 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3663 BitWidth, AS, PrevDecl, &D); 3664 if (NewFD->isInvalidDecl() && PrevDecl) { 3665 // Don't introduce NewFD into scope; there's already something 3666 // with the same name in the same scope. 3667 } else if (II) { 3668 PushOnScopeChains(NewFD, S); 3669 } else 3670 Record->addDecl(Context, NewFD); 3671 3672 return NewFD; 3673} 3674 3675/// \brief Build a new FieldDecl and check its well-formedness. 3676/// 3677/// This routine builds a new FieldDecl given the fields name, type, 3678/// record, etc. \p PrevDecl should refer to any previous declaration 3679/// with the same name and in the same scope as the field to be 3680/// created. 3681/// 3682/// \returns a new FieldDecl. 3683/// 3684/// \todo The Declarator argument is a hack. It will be removed once 3685FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3686 RecordDecl *Record, SourceLocation Loc, 3687 bool Mutable, Expr *BitWidth, 3688 AccessSpecifier AS, NamedDecl *PrevDecl, 3689 Declarator *D) { 3690 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3691 bool InvalidDecl = false; 3692 if (D) InvalidDecl = D->isInvalidType(); 3693 3694 // If we receive a broken type, recover by assuming 'int' and 3695 // marking this declaration as invalid. 3696 if (T.isNull()) { 3697 InvalidDecl = true; 3698 T = Context.IntTy; 3699 } 3700 3701 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3702 // than a variably modified type. 3703 if (T->isVariablyModifiedType()) { 3704 bool SizeIsNegative; 3705 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3706 SizeIsNegative); 3707 if (!FixedTy.isNull()) { 3708 Diag(Loc, diag::warn_illegal_constant_array_size); 3709 T = FixedTy; 3710 } else { 3711 if (SizeIsNegative) 3712 Diag(Loc, diag::err_typecheck_negative_array_size); 3713 else 3714 Diag(Loc, diag::err_typecheck_field_variable_size); 3715 T = Context.IntTy; 3716 InvalidDecl = true; 3717 } 3718 } 3719 3720 // Fields can not have abstract class types 3721 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3722 AbstractFieldType)) 3723 InvalidDecl = true; 3724 3725 // If this is declared as a bit-field, check the bit-field. 3726 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3727 InvalidDecl = true; 3728 DeleteExpr(BitWidth); 3729 BitWidth = 0; 3730 } 3731 3732 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3733 Mutable); 3734 if (InvalidDecl) 3735 NewFD->setInvalidDecl(); 3736 3737 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3738 Diag(Loc, diag::err_duplicate_member) << II; 3739 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3740 NewFD->setInvalidDecl(); 3741 Record->setInvalidDecl(); 3742 } 3743 3744 if (getLangOptions().CPlusPlus && !T->isPODType()) 3745 cast<CXXRecordDecl>(Record)->setPOD(false); 3746 3747 // FIXME: We need to pass in the attributes given an AST 3748 // representation, not a parser representation. 3749 if (D) 3750 ProcessDeclAttributes(NewFD, *D); 3751 3752 if (T.isObjCGCWeak()) 3753 Diag(Loc, diag::warn_attribute_weak_on_field); 3754 3755 NewFD->setAccess(AS); 3756 3757 // C++ [dcl.init.aggr]p1: 3758 // An aggregate is an array or a class (clause 9) with [...] no 3759 // private or protected non-static data members (clause 11). 3760 // A POD must be an aggregate. 3761 if (getLangOptions().CPlusPlus && 3762 (AS == AS_private || AS == AS_protected)) { 3763 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3764 CXXRecord->setAggregate(false); 3765 CXXRecord->setPOD(false); 3766 } 3767 3768 return NewFD; 3769} 3770 3771/// TranslateIvarVisibility - Translate visibility from a token ID to an 3772/// AST enum value. 3773static ObjCIvarDecl::AccessControl 3774TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3775 switch (ivarVisibility) { 3776 default: assert(0 && "Unknown visitibility kind"); 3777 case tok::objc_private: return ObjCIvarDecl::Private; 3778 case tok::objc_public: return ObjCIvarDecl::Public; 3779 case tok::objc_protected: return ObjCIvarDecl::Protected; 3780 case tok::objc_package: return ObjCIvarDecl::Package; 3781 } 3782} 3783 3784/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3785/// in order to create an IvarDecl object for it. 3786Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3787 SourceLocation DeclStart, 3788 Declarator &D, ExprTy *BitfieldWidth, 3789 tok::ObjCKeywordKind Visibility) { 3790 3791 IdentifierInfo *II = D.getIdentifier(); 3792 Expr *BitWidth = (Expr*)BitfieldWidth; 3793 SourceLocation Loc = DeclStart; 3794 if (II) Loc = D.getIdentifierLoc(); 3795 3796 // FIXME: Unnamed fields can be handled in various different ways, for 3797 // example, unnamed unions inject all members into the struct namespace! 3798 3799 QualType T = GetTypeForDeclarator(D, S); 3800 3801 if (BitWidth) { 3802 // 6.7.2.1p3, 6.7.2.1p4 3803 if (VerifyBitField(Loc, II, T, BitWidth)) { 3804 D.setInvalidType(); 3805 DeleteExpr(BitWidth); 3806 BitWidth = 0; 3807 } 3808 } else { 3809 // Not a bitfield. 3810 3811 // validate II. 3812 3813 } 3814 3815 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3816 // than a variably modified type. 3817 if (T->isVariablyModifiedType()) { 3818 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3819 D.setInvalidType(); 3820 } 3821 3822 // Get the visibility (access control) for this ivar. 3823 ObjCIvarDecl::AccessControl ac = 3824 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3825 : ObjCIvarDecl::None; 3826 3827 // Construct the decl. 3828 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3829 (Expr *)BitfieldWidth); 3830 3831 if (II) { 3832 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3833 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3834 && !isa<TagDecl>(PrevDecl)) { 3835 Diag(Loc, diag::err_duplicate_member) << II; 3836 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3837 NewID->setInvalidDecl(); 3838 } 3839 } 3840 3841 // Process attributes attached to the ivar. 3842 ProcessDeclAttributes(NewID, D); 3843 3844 if (D.isInvalidType()) 3845 NewID->setInvalidDecl(); 3846 3847 if (II) { 3848 // FIXME: When interfaces are DeclContexts, we'll need to add 3849 // these to the interface. 3850 S->AddDecl(DeclPtrTy::make(NewID)); 3851 IdResolver.AddDecl(NewID); 3852 } 3853 3854 return DeclPtrTy::make(NewID); 3855} 3856 3857void Sema::ActOnFields(Scope* S, 3858 SourceLocation RecLoc, DeclPtrTy RecDecl, 3859 DeclPtrTy *Fields, unsigned NumFields, 3860 SourceLocation LBrac, SourceLocation RBrac, 3861 AttributeList *Attr) { 3862 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3863 assert(EnclosingDecl && "missing record or interface decl"); 3864 3865 // If the decl this is being inserted into is invalid, then it may be a 3866 // redeclaration or some other bogus case. Don't try to add fields to it. 3867 if (EnclosingDecl->isInvalidDecl()) { 3868 // FIXME: Deallocate fields? 3869 return; 3870 } 3871 3872 3873 // Verify that all the fields are okay. 3874 unsigned NumNamedMembers = 0; 3875 llvm::SmallVector<FieldDecl*, 32> RecFields; 3876 3877 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3878 for (unsigned i = 0; i != NumFields; ++i) { 3879 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3880 3881 // Get the type for the field. 3882 Type *FDTy = FD->getType().getTypePtr(); 3883 3884 if (!FD->isAnonymousStructOrUnion()) { 3885 // Remember all fields written by the user. 3886 RecFields.push_back(FD); 3887 } 3888 3889 // If the field is already invalid for some reason, don't emit more 3890 // diagnostics about it. 3891 if (FD->isInvalidDecl()) 3892 continue; 3893 3894 // C99 6.7.2.1p2: 3895 // A structure or union shall not contain a member with 3896 // incomplete or function type (hence, a structure shall not 3897 // contain an instance of itself, but may contain a pointer to 3898 // an instance of itself), except that the last member of a 3899 // structure with more than one named member may have incomplete 3900 // array type; such a structure (and any union containing, 3901 // possibly recursively, a member that is such a structure) 3902 // shall not be a member of a structure or an element of an 3903 // array. 3904 if (FDTy->isFunctionType()) { 3905 // Field declared as a function. 3906 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3907 << FD->getDeclName(); 3908 FD->setInvalidDecl(); 3909 EnclosingDecl->setInvalidDecl(); 3910 continue; 3911 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3912 Record && Record->isStruct()) { 3913 // Flexible array member. 3914 if (NumNamedMembers < 1) { 3915 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3916 << FD->getDeclName(); 3917 FD->setInvalidDecl(); 3918 EnclosingDecl->setInvalidDecl(); 3919 continue; 3920 } 3921 // Okay, we have a legal flexible array member at the end of the struct. 3922 if (Record) 3923 Record->setHasFlexibleArrayMember(true); 3924 } else if (!FDTy->isDependentType() && 3925 RequireCompleteType(FD->getLocation(), FD->getType(), 3926 diag::err_field_incomplete)) { 3927 // Incomplete type 3928 FD->setInvalidDecl(); 3929 EnclosingDecl->setInvalidDecl(); 3930 continue; 3931 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3932 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3933 // If this is a member of a union, then entire union becomes "flexible". 3934 if (Record && Record->isUnion()) { 3935 Record->setHasFlexibleArrayMember(true); 3936 } else { 3937 // If this is a struct/class and this is not the last element, reject 3938 // it. Note that GCC supports variable sized arrays in the middle of 3939 // structures. 3940 if (i != NumFields-1) 3941 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3942 << FD->getDeclName() << FD->getType(); 3943 else { 3944 // We support flexible arrays at the end of structs in 3945 // other structs as an extension. 3946 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3947 << FD->getDeclName(); 3948 if (Record) 3949 Record->setHasFlexibleArrayMember(true); 3950 } 3951 } 3952 } 3953 } else if (FDTy->isObjCInterfaceType()) { 3954 /// A field cannot be an Objective-c object 3955 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3956 FD->setInvalidDecl(); 3957 EnclosingDecl->setInvalidDecl(); 3958 continue; 3959 } 3960 // Keep track of the number of named members. 3961 if (FD->getIdentifier()) 3962 ++NumNamedMembers; 3963 } 3964 3965 // Okay, we successfully defined 'Record'. 3966 if (Record) { 3967 Record->completeDefinition(Context); 3968 } else { 3969 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3970 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3971 ID->setIVarList(ClsFields, RecFields.size(), Context); 3972 ID->setLocEnd(RBrac); 3973 3974 // Must enforce the rule that ivars in the base classes may not be 3975 // duplicates. 3976 if (ID->getSuperClass()) { 3977 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3978 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3979 ObjCIvarDecl* Ivar = (*IVI); 3980 IdentifierInfo *II = Ivar->getIdentifier(); 3981 ObjCIvarDecl* prevIvar = 3982 ID->getSuperClass()->lookupInstanceVariable(Context, II); 3983 if (prevIvar) { 3984 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3985 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3986 } 3987 } 3988 } 3989 } else if (ObjCImplementationDecl *IMPDecl = 3990 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3991 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3992 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) { 3993 // FIXME: Set the DeclContext correctly when we build the 3994 // declarations. 3995 ClsFields[I]->setLexicalDeclContext(IMPDecl); 3996 IMPDecl->addDecl(Context, ClsFields[I]); 3997 } 3998 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3999 } 4000 } 4001 4002 if (Attr) 4003 ProcessDeclAttributeList(Record, Attr); 4004} 4005 4006EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4007 EnumConstantDecl *LastEnumConst, 4008 SourceLocation IdLoc, 4009 IdentifierInfo *Id, 4010 ExprArg val) { 4011 Expr *Val = (Expr *)val.get(); 4012 4013 llvm::APSInt EnumVal(32); 4014 QualType EltTy; 4015 if (Val && !Val->isTypeDependent()) { 4016 // Make sure to promote the operand type to int. 4017 UsualUnaryConversions(Val); 4018 if (Val != val.get()) { 4019 val.release(); 4020 val = Val; 4021 } 4022 4023 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4024 SourceLocation ExpLoc; 4025 if (!Val->isValueDependent() && 4026 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4027 Val = 0; 4028 } else { 4029 EltTy = Val->getType(); 4030 } 4031 } 4032 4033 if (!Val) { 4034 if (LastEnumConst) { 4035 // Assign the last value + 1. 4036 EnumVal = LastEnumConst->getInitVal(); 4037 ++EnumVal; 4038 4039 // Check for overflow on increment. 4040 if (EnumVal < LastEnumConst->getInitVal()) 4041 Diag(IdLoc, diag::warn_enum_value_overflow); 4042 4043 EltTy = LastEnumConst->getType(); 4044 } else { 4045 // First value, set to zero. 4046 EltTy = Context.IntTy; 4047 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4048 } 4049 } 4050 4051 val.release(); 4052 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4053 Val, EnumVal); 4054} 4055 4056 4057Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4058 DeclPtrTy lastEnumConst, 4059 SourceLocation IdLoc, 4060 IdentifierInfo *Id, 4061 SourceLocation EqualLoc, ExprTy *val) { 4062 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4063 EnumConstantDecl *LastEnumConst = 4064 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4065 Expr *Val = static_cast<Expr*>(val); 4066 4067 // The scope passed in may not be a decl scope. Zip up the scope tree until 4068 // we find one that is. 4069 S = getNonFieldDeclScope(S); 4070 4071 // Verify that there isn't already something declared with this name in this 4072 // scope. 4073 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4074 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4075 // Maybe we will complain about the shadowed template parameter. 4076 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4077 // Just pretend that we didn't see the previous declaration. 4078 PrevDecl = 0; 4079 } 4080 4081 if (PrevDecl) { 4082 // When in C++, we may get a TagDecl with the same name; in this case the 4083 // enum constant will 'hide' the tag. 4084 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4085 "Received TagDecl when not in C++!"); 4086 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4087 if (isa<EnumConstantDecl>(PrevDecl)) 4088 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4089 else 4090 Diag(IdLoc, diag::err_redefinition) << Id; 4091 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4092 if (Val) Val->Destroy(Context); 4093 return DeclPtrTy(); 4094 } 4095 } 4096 4097 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4098 IdLoc, Id, Owned(Val)); 4099 4100 // Register this decl in the current scope stack. 4101 if (New) 4102 PushOnScopeChains(New, S); 4103 4104 return DeclPtrTy::make(New); 4105} 4106 4107// FIXME: For consistency with ActOnFields(), we should have the parser 4108// pass in the source location for the left/right braces. 4109void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4110 DeclPtrTy *Elements, unsigned NumElements) { 4111 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4112 QualType EnumType = Context.getTypeDeclType(Enum); 4113 4114 // TODO: If the result value doesn't fit in an int, it must be a long or long 4115 // long value. ISO C does not support this, but GCC does as an extension, 4116 // emit a warning. 4117 unsigned IntWidth = Context.Target.getIntWidth(); 4118 4119 // Verify that all the values are okay, compute the size of the values, and 4120 // reverse the list. 4121 unsigned NumNegativeBits = 0; 4122 unsigned NumPositiveBits = 0; 4123 4124 // Keep track of whether all elements have type int. 4125 bool AllElementsInt = true; 4126 4127 for (unsigned i = 0; i != NumElements; ++i) { 4128 EnumConstantDecl *ECD = 4129 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4130 if (!ECD) continue; // Already issued a diagnostic. 4131 4132 // If the enum value doesn't fit in an int, emit an extension warning. 4133 const llvm::APSInt &InitVal = ECD->getInitVal(); 4134 assert(InitVal.getBitWidth() >= IntWidth && 4135 "Should have promoted value to int"); 4136 if (InitVal.getBitWidth() > IntWidth) { 4137 llvm::APSInt V(InitVal); 4138 V.trunc(IntWidth); 4139 V.extend(InitVal.getBitWidth()); 4140 if (V != InitVal) 4141 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4142 << InitVal.toString(10); 4143 } 4144 4145 // Keep track of the size of positive and negative values. 4146 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4147 NumPositiveBits = std::max(NumPositiveBits, 4148 (unsigned)InitVal.getActiveBits()); 4149 else 4150 NumNegativeBits = std::max(NumNegativeBits, 4151 (unsigned)InitVal.getMinSignedBits()); 4152 4153 // Keep track of whether every enum element has type int (very commmon). 4154 if (AllElementsInt) 4155 AllElementsInt = ECD->getType() == Context.IntTy; 4156 } 4157 4158 // Figure out the type that should be used for this enum. 4159 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4160 QualType BestType; 4161 unsigned BestWidth; 4162 4163 if (NumNegativeBits) { 4164 // If there is a negative value, figure out the smallest integer type (of 4165 // int/long/longlong) that fits. 4166 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4167 BestType = Context.IntTy; 4168 BestWidth = IntWidth; 4169 } else { 4170 BestWidth = Context.Target.getLongWidth(); 4171 4172 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4173 BestType = Context.LongTy; 4174 else { 4175 BestWidth = Context.Target.getLongLongWidth(); 4176 4177 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4178 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4179 BestType = Context.LongLongTy; 4180 } 4181 } 4182 } else { 4183 // If there is no negative value, figure out which of uint, ulong, ulonglong 4184 // fits. 4185 if (NumPositiveBits <= IntWidth) { 4186 BestType = Context.UnsignedIntTy; 4187 BestWidth = IntWidth; 4188 } else if (NumPositiveBits <= 4189 (BestWidth = Context.Target.getLongWidth())) { 4190 BestType = Context.UnsignedLongTy; 4191 } else { 4192 BestWidth = Context.Target.getLongLongWidth(); 4193 assert(NumPositiveBits <= BestWidth && 4194 "How could an initializer get larger than ULL?"); 4195 BestType = Context.UnsignedLongLongTy; 4196 } 4197 } 4198 4199 // Loop over all of the enumerator constants, changing their types to match 4200 // the type of the enum if needed. 4201 for (unsigned i = 0; i != NumElements; ++i) { 4202 EnumConstantDecl *ECD = 4203 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4204 if (!ECD) continue; // Already issued a diagnostic. 4205 4206 // Standard C says the enumerators have int type, but we allow, as an 4207 // extension, the enumerators to be larger than int size. If each 4208 // enumerator value fits in an int, type it as an int, otherwise type it the 4209 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4210 // that X has type 'int', not 'unsigned'. 4211 if (ECD->getType() == Context.IntTy) { 4212 // Make sure the init value is signed. 4213 llvm::APSInt IV = ECD->getInitVal(); 4214 IV.setIsSigned(true); 4215 ECD->setInitVal(IV); 4216 4217 if (getLangOptions().CPlusPlus) 4218 // C++ [dcl.enum]p4: Following the closing brace of an 4219 // enum-specifier, each enumerator has the type of its 4220 // enumeration. 4221 ECD->setType(EnumType); 4222 continue; // Already int type. 4223 } 4224 4225 // Determine whether the value fits into an int. 4226 llvm::APSInt InitVal = ECD->getInitVal(); 4227 bool FitsInInt; 4228 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4229 FitsInInt = InitVal.getActiveBits() < IntWidth; 4230 else 4231 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4232 4233 // If it fits into an integer type, force it. Otherwise force it to match 4234 // the enum decl type. 4235 QualType NewTy; 4236 unsigned NewWidth; 4237 bool NewSign; 4238 if (FitsInInt) { 4239 NewTy = Context.IntTy; 4240 NewWidth = IntWidth; 4241 NewSign = true; 4242 } else if (ECD->getType() == BestType) { 4243 // Already the right type! 4244 if (getLangOptions().CPlusPlus) 4245 // C++ [dcl.enum]p4: Following the closing brace of an 4246 // enum-specifier, each enumerator has the type of its 4247 // enumeration. 4248 ECD->setType(EnumType); 4249 continue; 4250 } else { 4251 NewTy = BestType; 4252 NewWidth = BestWidth; 4253 NewSign = BestType->isSignedIntegerType(); 4254 } 4255 4256 // Adjust the APSInt value. 4257 InitVal.extOrTrunc(NewWidth); 4258 InitVal.setIsSigned(NewSign); 4259 ECD->setInitVal(InitVal); 4260 4261 // Adjust the Expr initializer and type. 4262 if (ECD->getInitExpr()) 4263 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4264 /*isLvalue=*/false)); 4265 if (getLangOptions().CPlusPlus) 4266 // C++ [dcl.enum]p4: Following the closing brace of an 4267 // enum-specifier, each enumerator has the type of its 4268 // enumeration. 4269 ECD->setType(EnumType); 4270 else 4271 ECD->setType(NewTy); 4272 } 4273 4274 Enum->completeDefinition(Context, BestType); 4275} 4276 4277Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4278 ExprArg expr) { 4279 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4280 4281 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4282 Loc, AsmString)); 4283} 4284 4285