SemaDecl.cpp revision 516ff43cc4e20b637335d3dfa5b197ca8faa09cb
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/Parse/DeclSpec.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31using namespace clang; 32 33/// getDeclName - Return a pretty name for the specified decl if possible, or 34/// an empty string if not. This is used for pretty crash reporting. 35std::string Sema::getDeclName(DeclPtrTy d) { 36 Decl *D = d.getAs<Decl>(); 37 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 38 return DN->getQualifiedNameAsString(); 39 return ""; 40} 41 42Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 43 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 44} 45 46/// \brief If the identifier refers to a type name within this scope, 47/// return the declaration of that type. 48/// 49/// This routine performs ordinary name lookup of the identifier II 50/// within the given scope, with optional C++ scope specifier SS, to 51/// determine whether the name refers to a type. If so, returns an 52/// opaque pointer (actually a QualType) corresponding to that 53/// type. Otherwise, returns NULL. 54/// 55/// If name lookup results in an ambiguity, this routine will complain 56/// and then return NULL. 57Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 58 Scope *S, const CXXScopeSpec *SS) { 59 // C++ [temp.res]p3: 60 // A qualified-id that refers to a type and in which the 61 // nested-name-specifier depends on a template-parameter (14.6.2) 62 // shall be prefixed by the keyword typename to indicate that the 63 // qualified-id denotes a type, forming an 64 // elaborated-type-specifier (7.1.5.3). 65 // 66 // We therefore do not perform any name lookup up SS is a dependent 67 // scope name. FIXME: we will need to perform a special kind of 68 // lookup if the scope specifier names a member of the current 69 // instantiation. 70 if (SS && isDependentScopeSpecifier(*SS)) 71 return 0; 72 73 NamedDecl *IIDecl = 0; 74 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 75 false, false); 76 switch (Result.getKind()) { 77 case LookupResult::NotFound: 78 case LookupResult::FoundOverloaded: 79 return 0; 80 81 case LookupResult::AmbiguousBaseSubobjectTypes: 82 case LookupResult::AmbiguousBaseSubobjects: 83 case LookupResult::AmbiguousReference: { 84 // Look to see if we have a type anywhere in the list of results. 85 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 86 Res != ResEnd; ++Res) { 87 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 88 if (!IIDecl || 89 (*Res)->getLocation().getRawEncoding() < 90 IIDecl->getLocation().getRawEncoding()) 91 IIDecl = *Res; 92 } 93 } 94 95 if (!IIDecl) { 96 // None of the entities we found is a type, so there is no way 97 // to even assume that the result is a type. In this case, don't 98 // complain about the ambiguity. The parser will either try to 99 // perform this lookup again (e.g., as an object name), which 100 // will produce the ambiguity, or will complain that it expected 101 // a type name. 102 Result.Destroy(); 103 return 0; 104 } 105 106 // We found a type within the ambiguous lookup; diagnose the 107 // ambiguity and then return that type. This might be the right 108 // answer, or it might not be, but it suppresses any attempt to 109 // perform the name lookup again. 110 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 111 break; 112 } 113 114 case LookupResult::Found: 115 IIDecl = Result.getAsDecl(); 116 break; 117 } 118 119 if (IIDecl) { 120 QualType T; 121 122 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 123 // Check whether we can use this type 124 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 125 126 T = Context.getTypeDeclType(TD); 127 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 128 // Check whether we can use this interface. 129 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 130 131 T = Context.getObjCInterfaceType(IDecl); 132 } else 133 return 0; 134 135 if (SS) 136 T = getQualifiedNameType(*SS, T); 137 138 return T.getAsOpaquePtr(); 139 } 140 141 return 0; 142} 143 144/// isTagName() - This method is called *for error recovery purposes only* 145/// to determine if the specified name is a valid tag name ("struct foo"). If 146/// so, this returns the TST for the tag corresponding to it (TST_enum, 147/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 148/// where the user forgot to specify the tag. 149DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 150 // Do a tag name lookup in this scope. 151 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 152 if (R.getKind() == LookupResult::Found) 153 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 154 switch (TD->getTagKind()) { 155 case TagDecl::TK_struct: return DeclSpec::TST_struct; 156 case TagDecl::TK_union: return DeclSpec::TST_union; 157 case TagDecl::TK_class: return DeclSpec::TST_class; 158 case TagDecl::TK_enum: return DeclSpec::TST_enum; 159 } 160 } 161 162 return DeclSpec::TST_unspecified; 163} 164 165 166 167DeclContext *Sema::getContainingDC(DeclContext *DC) { 168 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 169 // A C++ out-of-line method will return to the file declaration context. 170 if (MD->isOutOfLineDefinition()) 171 return MD->getLexicalDeclContext(); 172 173 // A C++ inline method is parsed *after* the topmost class it was declared 174 // in is fully parsed (it's "complete"). 175 // The parsing of a C++ inline method happens at the declaration context of 176 // the topmost (non-nested) class it is lexically declared in. 177 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 178 DC = MD->getParent(); 179 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 180 DC = RD; 181 182 // Return the declaration context of the topmost class the inline method is 183 // declared in. 184 return DC; 185 } 186 187 if (isa<ObjCMethodDecl>(DC)) 188 return Context.getTranslationUnitDecl(); 189 190 return DC->getLexicalParent(); 191} 192 193void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 194 assert(getContainingDC(DC) == CurContext && 195 "The next DeclContext should be lexically contained in the current one."); 196 CurContext = DC; 197 S->setEntity(DC); 198} 199 200void Sema::PopDeclContext() { 201 assert(CurContext && "DeclContext imbalance!"); 202 203 CurContext = getContainingDC(CurContext); 204} 205 206/// \brief Determine whether we allow overloading of the function 207/// PrevDecl with another declaration. 208/// 209/// This routine determines whether overloading is possible, not 210/// whether some new function is actually an overload. It will return 211/// true in C++ (where we can always provide overloads) or, as an 212/// extension, in C when the previous function is already an 213/// overloaded function declaration or has the "overloadable" 214/// attribute. 215static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 216 if (Context.getLangOptions().CPlusPlus) 217 return true; 218 219 if (isa<OverloadedFunctionDecl>(PrevDecl)) 220 return true; 221 222 return PrevDecl->getAttr<OverloadableAttr>() != 0; 223} 224 225/// Add this decl to the scope shadowed decl chains. 226void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 227 // Move up the scope chain until we find the nearest enclosing 228 // non-transparent context. The declaration will be introduced into this 229 // scope. 230 while (S->getEntity() && 231 ((DeclContext *)S->getEntity())->isTransparentContext()) 232 S = S->getParent(); 233 234 S->AddDecl(DeclPtrTy::make(D)); 235 236 // Add scoped declarations into their context, so that they can be 237 // found later. Declarations without a context won't be inserted 238 // into any context. 239 CurContext->addDecl(Context, D); 240 241 // C++ [basic.scope]p4: 242 // -- exactly one declaration shall declare a class name or 243 // enumeration name that is not a typedef name and the other 244 // declarations shall all refer to the same object or 245 // enumerator, or all refer to functions and function templates; 246 // in this case the class name or enumeration name is hidden. 247 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 248 // We are pushing the name of a tag (enum or class). 249 if (CurContext->getLookupContext() 250 == TD->getDeclContext()->getLookupContext()) { 251 // We're pushing the tag into the current context, which might 252 // require some reshuffling in the identifier resolver. 253 IdentifierResolver::iterator 254 I = IdResolver.begin(TD->getDeclName()), 255 IEnd = IdResolver.end(); 256 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 257 NamedDecl *PrevDecl = *I; 258 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 259 PrevDecl = *I, ++I) { 260 if (TD->declarationReplaces(*I)) { 261 // This is a redeclaration. Remove it from the chain and 262 // break out, so that we'll add in the shadowed 263 // declaration. 264 S->RemoveDecl(DeclPtrTy::make(*I)); 265 if (PrevDecl == *I) { 266 IdResolver.RemoveDecl(*I); 267 IdResolver.AddDecl(TD); 268 return; 269 } else { 270 IdResolver.RemoveDecl(*I); 271 break; 272 } 273 } 274 } 275 276 // There is already a declaration with the same name in the same 277 // scope, which is not a tag declaration. It must be found 278 // before we find the new declaration, so insert the new 279 // declaration at the end of the chain. 280 IdResolver.AddShadowedDecl(TD, PrevDecl); 281 282 return; 283 } 284 } 285 } else if (isa<FunctionDecl>(D) && 286 AllowOverloadingOfFunction(D, Context)) { 287 // We are pushing the name of a function, which might be an 288 // overloaded name. 289 FunctionDecl *FD = cast<FunctionDecl>(D); 290 IdentifierResolver::iterator Redecl 291 = std::find_if(IdResolver.begin(FD->getDeclName()), 292 IdResolver.end(), 293 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 294 FD)); 295 if (Redecl != IdResolver.end() && 296 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 297 // There is already a declaration of a function on our 298 // IdResolver chain. Replace it with this declaration. 299 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 300 IdResolver.RemoveDecl(*Redecl); 301 } 302 } else if (isa<ObjCInterfaceDecl>(D)) { 303 // We're pushing an Objective-C interface into the current 304 // context. If there is already an alias declaration, remove it first. 305 for (IdentifierResolver::iterator 306 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 307 I != IEnd; ++I) { 308 if (isa<ObjCCompatibleAliasDecl>(*I)) { 309 S->RemoveDecl(DeclPtrTy::make(*I)); 310 IdResolver.RemoveDecl(*I); 311 break; 312 } 313 } 314 } 315 316 IdResolver.AddDecl(D); 317} 318 319void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 320 if (S->decl_empty()) return; 321 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 322 "Scope shouldn't contain decls!"); 323 324 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 325 I != E; ++I) { 326 Decl *TmpD = (*I).getAs<Decl>(); 327 assert(TmpD && "This decl didn't get pushed??"); 328 329 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 330 NamedDecl *D = cast<NamedDecl>(TmpD); 331 332 if (!D->getDeclName()) continue; 333 334 // Remove this name from our lexical scope. 335 IdResolver.RemoveDecl(D); 336 } 337} 338 339/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 340/// return 0 if one not found. 341ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 342 // The third "scope" argument is 0 since we aren't enabling lazy built-in 343 // creation from this context. 344 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 345 346 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 347} 348 349/// getNonFieldDeclScope - Retrieves the innermost scope, starting 350/// from S, where a non-field would be declared. This routine copes 351/// with the difference between C and C++ scoping rules in structs and 352/// unions. For example, the following code is well-formed in C but 353/// ill-formed in C++: 354/// @code 355/// struct S6 { 356/// enum { BAR } e; 357/// }; 358/// 359/// void test_S6() { 360/// struct S6 a; 361/// a.e = BAR; 362/// } 363/// @endcode 364/// For the declaration of BAR, this routine will return a different 365/// scope. The scope S will be the scope of the unnamed enumeration 366/// within S6. In C++, this routine will return the scope associated 367/// with S6, because the enumeration's scope is a transparent 368/// context but structures can contain non-field names. In C, this 369/// routine will return the translation unit scope, since the 370/// enumeration's scope is a transparent context and structures cannot 371/// contain non-field names. 372Scope *Sema::getNonFieldDeclScope(Scope *S) { 373 while (((S->getFlags() & Scope::DeclScope) == 0) || 374 (S->getEntity() && 375 ((DeclContext *)S->getEntity())->isTransparentContext()) || 376 (S->isClassScope() && !getLangOptions().CPlusPlus)) 377 S = S->getParent(); 378 return S; 379} 380 381void Sema::InitBuiltinVaListType() { 382 if (!Context.getBuiltinVaListType().isNull()) 383 return; 384 385 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 386 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 387 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 388 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 389} 390 391/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 392/// file scope. lazily create a decl for it. ForRedeclaration is true 393/// if we're creating this built-in in anticipation of redeclaring the 394/// built-in. 395NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 396 Scope *S, bool ForRedeclaration, 397 SourceLocation Loc) { 398 Builtin::ID BID = (Builtin::ID)bid; 399 400 if (Context.BuiltinInfo.hasVAListUse(BID)) 401 InitBuiltinVaListType(); 402 403 Builtin::Context::GetBuiltinTypeError Error; 404 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 405 switch (Error) { 406 case Builtin::Context::GE_None: 407 // Okay 408 break; 409 410 case Builtin::Context::GE_Missing_FILE: 411 if (ForRedeclaration) 412 Diag(Loc, diag::err_implicit_decl_requires_stdio) 413 << Context.BuiltinInfo.GetName(BID); 414 return 0; 415 } 416 417 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 418 Diag(Loc, diag::ext_implicit_lib_function_decl) 419 << Context.BuiltinInfo.GetName(BID) 420 << R; 421 if (Context.BuiltinInfo.getHeaderName(BID) && 422 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 423 != Diagnostic::Ignored) 424 Diag(Loc, diag::note_please_include_header) 425 << Context.BuiltinInfo.getHeaderName(BID) 426 << Context.BuiltinInfo.GetName(BID); 427 } 428 429 FunctionDecl *New = FunctionDecl::Create(Context, 430 Context.getTranslationUnitDecl(), 431 Loc, II, R, 432 FunctionDecl::Extern, false, 433 /*hasPrototype=*/true); 434 New->setImplicit(); 435 436 // Create Decl objects for each parameter, adding them to the 437 // FunctionDecl. 438 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 439 llvm::SmallVector<ParmVarDecl*, 16> Params; 440 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 441 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 442 FT->getArgType(i), VarDecl::None, 0)); 443 New->setParams(Context, &Params[0], Params.size()); 444 } 445 446 AddKnownFunctionAttributes(New); 447 448 // TUScope is the translation-unit scope to insert this function into. 449 // FIXME: This is hideous. We need to teach PushOnScopeChains to 450 // relate Scopes to DeclContexts, and probably eliminate CurContext 451 // entirely, but we're not there yet. 452 DeclContext *SavedContext = CurContext; 453 CurContext = Context.getTranslationUnitDecl(); 454 PushOnScopeChains(New, TUScope); 455 CurContext = SavedContext; 456 return New; 457} 458 459/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 460/// everything from the standard library is defined. 461NamespaceDecl *Sema::GetStdNamespace() { 462 if (!StdNamespace) { 463 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 464 DeclContext *Global = Context.getTranslationUnitDecl(); 465 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 466 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 467 } 468 return StdNamespace; 469} 470 471/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 472/// same name and scope as a previous declaration 'Old'. Figure out 473/// how to resolve this situation, merging decls or emitting 474/// diagnostics as appropriate. Returns true if there was an error, 475/// false otherwise. 476/// 477bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 478 bool objc_types = false; 479 // Allow multiple definitions for ObjC built-in typedefs. 480 // FIXME: Verify the underlying types are equivalent! 481 if (getLangOptions().ObjC1) { 482 const IdentifierInfo *TypeID = New->getIdentifier(); 483 switch (TypeID->getLength()) { 484 default: break; 485 case 2: 486 if (!TypeID->isStr("id")) 487 break; 488 Context.setObjCIdType(Context.getTypeDeclType(New)); 489 objc_types = true; 490 break; 491 case 5: 492 if (!TypeID->isStr("Class")) 493 break; 494 Context.setObjCClassType(Context.getTypeDeclType(New)); 495 objc_types = true; 496 return false; 497 case 3: 498 if (!TypeID->isStr("SEL")) 499 break; 500 Context.setObjCSelType(Context.getTypeDeclType(New)); 501 objc_types = true; 502 return false; 503 case 8: 504 if (!TypeID->isStr("Protocol")) 505 break; 506 Context.setObjCProtoType(New->getUnderlyingType()); 507 objc_types = true; 508 return false; 509 } 510 // Fall through - the typedef name was not a builtin type. 511 } 512 // Verify the old decl was also a type. 513 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 514 if (!Old) { 515 Diag(New->getLocation(), diag::err_redefinition_different_kind) 516 << New->getDeclName(); 517 if (!objc_types) 518 Diag(OldD->getLocation(), diag::note_previous_definition); 519 return true; 520 } 521 522 // Determine the "old" type we'll use for checking and diagnostics. 523 QualType OldType; 524 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 525 OldType = OldTypedef->getUnderlyingType(); 526 else 527 OldType = Context.getTypeDeclType(Old); 528 529 // If the typedef types are not identical, reject them in all languages and 530 // with any extensions enabled. 531 532 if (OldType != New->getUnderlyingType() && 533 Context.getCanonicalType(OldType) != 534 Context.getCanonicalType(New->getUnderlyingType())) { 535 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 536 << New->getUnderlyingType() << OldType; 537 if (!objc_types) 538 Diag(Old->getLocation(), diag::note_previous_definition); 539 return true; 540 } 541 if (objc_types) return false; 542 if (getLangOptions().Microsoft) return false; 543 544 // C++ [dcl.typedef]p2: 545 // In a given non-class scope, a typedef specifier can be used to 546 // redefine the name of any type declared in that scope to refer 547 // to the type to which it already refers. 548 if (getLangOptions().CPlusPlus) { 549 if (!isa<CXXRecordDecl>(CurContext)) 550 return false; 551 Diag(New->getLocation(), diag::err_redefinition) 552 << New->getDeclName(); 553 Diag(Old->getLocation(), diag::note_previous_definition); 554 return true; 555 } 556 557 // If we have a redefinition of a typedef in C, emit a warning. This warning 558 // is normally mapped to an error, but can be controlled with 559 // -Wtypedef-redefinition. 560 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 561 << New->getDeclName(); 562 Diag(Old->getLocation(), diag::note_previous_definition); 563 return false; 564} 565 566/// DeclhasAttr - returns true if decl Declaration already has the target 567/// attribute. 568static bool DeclHasAttr(const Decl *decl, const Attr *target) { 569 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 570 if (attr->getKind() == target->getKind()) 571 return true; 572 573 return false; 574} 575 576/// MergeAttributes - append attributes from the Old decl to the New one. 577static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 578 Attr *attr = const_cast<Attr*>(Old->getAttrs()); 579 580 while (attr) { 581 Attr *tmp = attr; 582 attr = attr->getNext(); 583 584 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 585 tmp->setInherited(true); 586 New->addAttr(tmp); 587 } else { 588 tmp->setNext(0); 589 tmp->Destroy(C); 590 } 591 } 592 593 Old->invalidateAttrs(); 594} 595 596/// Used in MergeFunctionDecl to keep track of function parameters in 597/// C. 598struct GNUCompatibleParamWarning { 599 ParmVarDecl *OldParm; 600 ParmVarDecl *NewParm; 601 QualType PromotedType; 602}; 603 604/// MergeFunctionDecl - We just parsed a function 'New' from 605/// declarator D which has the same name and scope as a previous 606/// declaration 'Old'. Figure out how to resolve this situation, 607/// merging decls or emitting diagnostics as appropriate. 608/// 609/// In C++, New and Old must be declarations that are not 610/// overloaded. Use IsOverload to determine whether New and Old are 611/// overloaded, and to select the Old declaration that New should be 612/// merged with. 613/// 614/// Returns true if there was an error, false otherwise. 615bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 616 assert(!isa<OverloadedFunctionDecl>(OldD) && 617 "Cannot merge with an overloaded function declaration"); 618 619 // Verify the old decl was also a function. 620 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 621 if (!Old) { 622 Diag(New->getLocation(), diag::err_redefinition_different_kind) 623 << New->getDeclName(); 624 Diag(OldD->getLocation(), diag::note_previous_definition); 625 return true; 626 } 627 628 // Determine whether the previous declaration was a definition, 629 // implicit declaration, or a declaration. 630 diag::kind PrevDiag; 631 if (Old->isThisDeclarationADefinition()) 632 PrevDiag = diag::note_previous_definition; 633 else if (Old->isImplicit()) 634 PrevDiag = diag::note_previous_implicit_declaration; 635 else 636 PrevDiag = diag::note_previous_declaration; 637 638 QualType OldQType = Context.getCanonicalType(Old->getType()); 639 QualType NewQType = Context.getCanonicalType(New->getType()); 640 641 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 642 New->getStorageClass() == FunctionDecl::Static && 643 Old->getStorageClass() != FunctionDecl::Static) { 644 Diag(New->getLocation(), diag::err_static_non_static) 645 << New; 646 Diag(Old->getLocation(), PrevDiag); 647 return true; 648 } 649 650 if (getLangOptions().CPlusPlus) { 651 // (C++98 13.1p2): 652 // Certain function declarations cannot be overloaded: 653 // -- Function declarations that differ only in the return type 654 // cannot be overloaded. 655 QualType OldReturnType 656 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 657 QualType NewReturnType 658 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 659 if (OldReturnType != NewReturnType) { 660 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 661 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 662 return true; 663 } 664 665 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 666 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 667 if (OldMethod && NewMethod && 668 OldMethod->getLexicalDeclContext() == 669 NewMethod->getLexicalDeclContext()) { 670 // -- Member function declarations with the same name and the 671 // same parameter types cannot be overloaded if any of them 672 // is a static member function declaration. 673 if (OldMethod->isStatic() || NewMethod->isStatic()) { 674 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 675 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 676 return true; 677 } 678 679 // C++ [class.mem]p1: 680 // [...] A member shall not be declared twice in the 681 // member-specification, except that a nested class or member 682 // class template can be declared and then later defined. 683 unsigned NewDiag; 684 if (isa<CXXConstructorDecl>(OldMethod)) 685 NewDiag = diag::err_constructor_redeclared; 686 else if (isa<CXXDestructorDecl>(NewMethod)) 687 NewDiag = diag::err_destructor_redeclared; 688 else if (isa<CXXConversionDecl>(NewMethod)) 689 NewDiag = diag::err_conv_function_redeclared; 690 else 691 NewDiag = diag::err_member_redeclared; 692 693 Diag(New->getLocation(), NewDiag); 694 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 695 } 696 697 // (C++98 8.3.5p3): 698 // All declarations for a function shall agree exactly in both the 699 // return type and the parameter-type-list. 700 if (OldQType == NewQType) 701 return MergeCompatibleFunctionDecls(New, Old); 702 703 // Fall through for conflicting redeclarations and redefinitions. 704 } 705 706 // C: Function types need to be compatible, not identical. This handles 707 // duplicate function decls like "void f(int); void f(enum X);" properly. 708 if (!getLangOptions().CPlusPlus && 709 Context.typesAreCompatible(OldQType, NewQType)) { 710 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 711 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 712 const FunctionProtoType *OldProto = 0; 713 if (isa<FunctionNoProtoType>(NewFuncType) && 714 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 715 // The old declaration provided a function prototype, but the 716 // new declaration does not. Merge in the prototype. 717 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 718 OldProto->arg_type_end()); 719 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 720 &ParamTypes[0], ParamTypes.size(), 721 OldProto->isVariadic(), 722 OldProto->getTypeQuals()); 723 New->setType(NewQType); 724 New->setInheritedPrototype(); 725 726 // Synthesize a parameter for each argument type. 727 llvm::SmallVector<ParmVarDecl*, 16> Params; 728 for (FunctionProtoType::arg_type_iterator 729 ParamType = OldProto->arg_type_begin(), 730 ParamEnd = OldProto->arg_type_end(); 731 ParamType != ParamEnd; ++ParamType) { 732 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 733 SourceLocation(), 0, 734 *ParamType, VarDecl::None, 735 0); 736 Param->setImplicit(); 737 Params.push_back(Param); 738 } 739 740 New->setParams(Context, &Params[0], Params.size()); 741 } 742 743 return MergeCompatibleFunctionDecls(New, Old); 744 } 745 746 // GNU C permits a K&R definition to follow a prototype declaration 747 // if the declared types of the parameters in the K&R definition 748 // match the types in the prototype declaration, even when the 749 // promoted types of the parameters from the K&R definition differ 750 // from the types in the prototype. GCC then keeps the types from 751 // the prototype. 752 if (!getLangOptions().CPlusPlus && 753 !getLangOptions().NoExtensions && 754 Old->hasPrototype() && !New->hasPrototype() && 755 New->getType()->getAsFunctionProtoType() && 756 Old->getNumParams() == New->getNumParams()) { 757 llvm::SmallVector<QualType, 16> ArgTypes; 758 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 759 const FunctionProtoType *OldProto 760 = Old->getType()->getAsFunctionProtoType(); 761 const FunctionProtoType *NewProto 762 = New->getType()->getAsFunctionProtoType(); 763 764 // Determine whether this is the GNU C extension. 765 bool GNUCompatible = 766 Context.typesAreCompatible(OldProto->getResultType(), 767 NewProto->getResultType()) && 768 (OldProto->isVariadic() == NewProto->isVariadic()); 769 for (unsigned Idx = 0, End = Old->getNumParams(); 770 GNUCompatible && Idx != End; ++Idx) { 771 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 772 ParmVarDecl *NewParm = New->getParamDecl(Idx); 773 if (Context.typesAreCompatible(OldParm->getType(), 774 NewProto->getArgType(Idx))) { 775 ArgTypes.push_back(NewParm->getType()); 776 } else if (Context.typesAreCompatible(OldParm->getType(), 777 NewParm->getType())) { 778 GNUCompatibleParamWarning Warn 779 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 780 Warnings.push_back(Warn); 781 ArgTypes.push_back(NewParm->getType()); 782 } else 783 GNUCompatible = false; 784 } 785 786 if (GNUCompatible) { 787 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 788 Diag(Warnings[Warn].NewParm->getLocation(), 789 diag::ext_param_promoted_not_compatible_with_prototype) 790 << Warnings[Warn].PromotedType 791 << Warnings[Warn].OldParm->getType(); 792 Diag(Warnings[Warn].OldParm->getLocation(), 793 diag::note_previous_declaration); 794 } 795 796 New->setType(Context.getFunctionType(NewProto->getResultType(), 797 &ArgTypes[0], ArgTypes.size(), 798 NewProto->isVariadic(), 799 NewProto->getTypeQuals())); 800 return MergeCompatibleFunctionDecls(New, Old); 801 } 802 803 // Fall through to diagnose conflicting types. 804 } 805 806 // A function that has already been declared has been redeclared or defined 807 // with a different type- show appropriate diagnostic 808 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 809 // The user has declared a builtin function with an incompatible 810 // signature. 811 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 812 // The function the user is redeclaring is a library-defined 813 // function like 'malloc' or 'printf'. Warn about the 814 // redeclaration, then pretend that we don't know about this 815 // library built-in. 816 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 817 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 818 << Old << Old->getType(); 819 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 820 Old->setInvalidDecl(); 821 return false; 822 } 823 824 PrevDiag = diag::note_previous_builtin_declaration; 825 } 826 827 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 828 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 829 return true; 830} 831 832/// \brief Completes the merge of two function declarations that are 833/// known to be compatible. 834/// 835/// This routine handles the merging of attributes and other 836/// properties of function declarations form the old declaration to 837/// the new declaration, once we know that New is in fact a 838/// redeclaration of Old. 839/// 840/// \returns false 841bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 842 // Merge the attributes 843 MergeAttributes(New, Old, Context); 844 845 // Merge the storage class. 846 New->setStorageClass(Old->getStorageClass()); 847 848 // Merge "inline" 849 if (Old->isInline()) 850 New->setInline(true); 851 852 // If this function declaration by itself qualifies as a C99 inline 853 // definition (C99 6.7.4p6), but the previous definition did not, 854 // then the function is not a C99 inline definition. 855 if (New->isC99InlineDefinition() && !Old->isC99InlineDefinition()) 856 New->setC99InlineDefinition(false); 857 else if (Old->isC99InlineDefinition() && !New->isC99InlineDefinition()) { 858 // Mark all preceding definitions as not being C99 inline definitions. 859 for (const FunctionDecl *Prev = Old; Prev; 860 Prev = Prev->getPreviousDeclaration()) 861 const_cast<FunctionDecl *>(Prev)->setC99InlineDefinition(false); 862 } 863 864 // Merge "pure" flag. 865 if (Old->isPure()) 866 New->setPure(); 867 868 // Merge the "deleted" flag. 869 if (Old->isDeleted()) 870 New->setDeleted(); 871 872 if (getLangOptions().CPlusPlus) 873 return MergeCXXFunctionDecl(New, Old); 874 875 return false; 876} 877 878/// MergeVarDecl - We just parsed a variable 'New' which has the same name 879/// and scope as a previous declaration 'Old'. Figure out how to resolve this 880/// situation, merging decls or emitting diagnostics as appropriate. 881/// 882/// Tentative definition rules (C99 6.9.2p2) are checked by 883/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 884/// definitions here, since the initializer hasn't been attached. 885/// 886bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 887 // Verify the old decl was also a variable. 888 VarDecl *Old = dyn_cast<VarDecl>(OldD); 889 if (!Old) { 890 Diag(New->getLocation(), diag::err_redefinition_different_kind) 891 << New->getDeclName(); 892 Diag(OldD->getLocation(), diag::note_previous_definition); 893 return true; 894 } 895 896 MergeAttributes(New, Old, Context); 897 898 // Merge the types 899 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 900 if (MergedT.isNull()) { 901 Diag(New->getLocation(), diag::err_redefinition_different_type) 902 << New->getDeclName(); 903 Diag(Old->getLocation(), diag::note_previous_definition); 904 return true; 905 } 906 New->setType(MergedT); 907 908 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 909 if (New->getStorageClass() == VarDecl::Static && 910 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 911 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 912 Diag(Old->getLocation(), diag::note_previous_definition); 913 return true; 914 } 915 // C99 6.2.2p4: 916 // For an identifier declared with the storage-class specifier 917 // extern in a scope in which a prior declaration of that 918 // identifier is visible,23) if the prior declaration specifies 919 // internal or external linkage, the linkage of the identifier at 920 // the later declaration is the same as the linkage specified at 921 // the prior declaration. If no prior declaration is visible, or 922 // if the prior declaration specifies no linkage, then the 923 // identifier has external linkage. 924 if (New->hasExternalStorage() && Old->hasLinkage()) 925 /* Okay */; 926 else if (New->getStorageClass() != VarDecl::Static && 927 Old->getStorageClass() == VarDecl::Static) { 928 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 929 Diag(Old->getLocation(), diag::note_previous_definition); 930 return true; 931 } 932 933 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 934 935 // FIXME: The test for external storage here seems wrong? We still 936 // need to check for mismatches. 937 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 938 // Don't complain about out-of-line definitions of static members. 939 !(Old->getLexicalDeclContext()->isRecord() && 940 !New->getLexicalDeclContext()->isRecord())) { 941 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 942 Diag(Old->getLocation(), diag::note_previous_definition); 943 return true; 944 } 945 946 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 947 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 948 Diag(Old->getLocation(), diag::note_previous_definition); 949 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 950 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 951 Diag(Old->getLocation(), diag::note_previous_definition); 952 } 953 954 // Keep a chain of previous declarations. 955 New->setPreviousDeclaration(Old); 956 957 return false; 958} 959 960/// CheckParmsForFunctionDef - Check that the parameters of the given 961/// function are appropriate for the definition of a function. This 962/// takes care of any checks that cannot be performed on the 963/// declaration itself, e.g., that the types of each of the function 964/// parameters are complete. 965bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 966 bool HasInvalidParm = false; 967 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 968 ParmVarDecl *Param = FD->getParamDecl(p); 969 970 // C99 6.7.5.3p4: the parameters in a parameter type list in a 971 // function declarator that is part of a function definition of 972 // that function shall not have incomplete type. 973 // 974 // This is also C++ [dcl.fct]p6. 975 if (!Param->isInvalidDecl() && 976 RequireCompleteType(Param->getLocation(), Param->getType(), 977 diag::err_typecheck_decl_incomplete_type)) { 978 Param->setInvalidDecl(); 979 HasInvalidParm = true; 980 } 981 982 // C99 6.9.1p5: If the declarator includes a parameter type list, the 983 // declaration of each parameter shall include an identifier. 984 if (Param->getIdentifier() == 0 && 985 !Param->isImplicit() && 986 !getLangOptions().CPlusPlus) 987 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 988 } 989 990 return HasInvalidParm; 991} 992 993/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 994/// no declarator (e.g. "struct foo;") is parsed. 995Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 996 // FIXME: Error on auto/register at file scope 997 // FIXME: Error on inline/virtual/explicit 998 // FIXME: Error on invalid restrict 999 // FIXME: Warn on useless __thread 1000 // FIXME: Warn on useless const/volatile 1001 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1002 // FIXME: Warn on useless attributes 1003 1004 TagDecl *Tag = 0; 1005 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1006 DS.getTypeSpecType() == DeclSpec::TST_struct || 1007 DS.getTypeSpecType() == DeclSpec::TST_union || 1008 DS.getTypeSpecType() == DeclSpec::TST_enum) 1009 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1010 1011 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1012 if (!Record->getDeclName() && Record->isDefinition() && 1013 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1014 if (getLangOptions().CPlusPlus || 1015 Record->getDeclContext()->isRecord()) 1016 return BuildAnonymousStructOrUnion(S, DS, Record); 1017 1018 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1019 << DS.getSourceRange(); 1020 } 1021 1022 // Microsoft allows unnamed struct/union fields. Don't complain 1023 // about them. 1024 // FIXME: Should we support Microsoft's extensions in this area? 1025 if (Record->getDeclName() && getLangOptions().Microsoft) 1026 return DeclPtrTy::make(Tag); 1027 } 1028 1029 if (!DS.isMissingDeclaratorOk() && 1030 DS.getTypeSpecType() != DeclSpec::TST_error) { 1031 // Warn about typedefs of enums without names, since this is an 1032 // extension in both Microsoft an GNU. 1033 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1034 Tag && isa<EnumDecl>(Tag)) { 1035 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1036 << DS.getSourceRange(); 1037 return DeclPtrTy::make(Tag); 1038 } 1039 1040 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1041 << DS.getSourceRange(); 1042 return DeclPtrTy(); 1043 } 1044 1045 return DeclPtrTy::make(Tag); 1046} 1047 1048/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1049/// anonymous struct or union AnonRecord into the owning context Owner 1050/// and scope S. This routine will be invoked just after we realize 1051/// that an unnamed union or struct is actually an anonymous union or 1052/// struct, e.g., 1053/// 1054/// @code 1055/// union { 1056/// int i; 1057/// float f; 1058/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1059/// // f into the surrounding scope.x 1060/// @endcode 1061/// 1062/// This routine is recursive, injecting the names of nested anonymous 1063/// structs/unions into the owning context and scope as well. 1064bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1065 RecordDecl *AnonRecord) { 1066 bool Invalid = false; 1067 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1068 FEnd = AnonRecord->field_end(Context); 1069 F != FEnd; ++F) { 1070 if ((*F)->getDeclName()) { 1071 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1072 LookupOrdinaryName, true); 1073 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1074 // C++ [class.union]p2: 1075 // The names of the members of an anonymous union shall be 1076 // distinct from the names of any other entity in the 1077 // scope in which the anonymous union is declared. 1078 unsigned diagKind 1079 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1080 : diag::err_anonymous_struct_member_redecl; 1081 Diag((*F)->getLocation(), diagKind) 1082 << (*F)->getDeclName(); 1083 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1084 Invalid = true; 1085 } else { 1086 // C++ [class.union]p2: 1087 // For the purpose of name lookup, after the anonymous union 1088 // definition, the members of the anonymous union are 1089 // considered to have been defined in the scope in which the 1090 // anonymous union is declared. 1091 Owner->makeDeclVisibleInContext(Context, *F); 1092 S->AddDecl(DeclPtrTy::make(*F)); 1093 IdResolver.AddDecl(*F); 1094 } 1095 } else if (const RecordType *InnerRecordType 1096 = (*F)->getType()->getAsRecordType()) { 1097 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1098 if (InnerRecord->isAnonymousStructOrUnion()) 1099 Invalid = Invalid || 1100 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1101 } 1102 } 1103 1104 return Invalid; 1105} 1106 1107/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1108/// anonymous structure or union. Anonymous unions are a C++ feature 1109/// (C++ [class.union]) and a GNU C extension; anonymous structures 1110/// are a GNU C and GNU C++ extension. 1111Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1112 RecordDecl *Record) { 1113 DeclContext *Owner = Record->getDeclContext(); 1114 1115 // Diagnose whether this anonymous struct/union is an extension. 1116 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1117 Diag(Record->getLocation(), diag::ext_anonymous_union); 1118 else if (!Record->isUnion()) 1119 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1120 1121 // C and C++ require different kinds of checks for anonymous 1122 // structs/unions. 1123 bool Invalid = false; 1124 if (getLangOptions().CPlusPlus) { 1125 const char* PrevSpec = 0; 1126 // C++ [class.union]p3: 1127 // Anonymous unions declared in a named namespace or in the 1128 // global namespace shall be declared static. 1129 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1130 (isa<TranslationUnitDecl>(Owner) || 1131 (isa<NamespaceDecl>(Owner) && 1132 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1133 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1134 Invalid = true; 1135 1136 // Recover by adding 'static'. 1137 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1138 } 1139 // C++ [class.union]p3: 1140 // A storage class is not allowed in a declaration of an 1141 // anonymous union in a class scope. 1142 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1143 isa<RecordDecl>(Owner)) { 1144 Diag(DS.getStorageClassSpecLoc(), 1145 diag::err_anonymous_union_with_storage_spec); 1146 Invalid = true; 1147 1148 // Recover by removing the storage specifier. 1149 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1150 PrevSpec); 1151 } 1152 1153 // C++ [class.union]p2: 1154 // The member-specification of an anonymous union shall only 1155 // define non-static data members. [Note: nested types and 1156 // functions cannot be declared within an anonymous union. ] 1157 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1158 MemEnd = Record->decls_end(Context); 1159 Mem != MemEnd; ++Mem) { 1160 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1161 // C++ [class.union]p3: 1162 // An anonymous union shall not have private or protected 1163 // members (clause 11). 1164 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1165 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1166 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1167 Invalid = true; 1168 } 1169 } else if ((*Mem)->isImplicit()) { 1170 // Any implicit members are fine. 1171 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1172 // This is a type that showed up in an 1173 // elaborated-type-specifier inside the anonymous struct or 1174 // union, but which actually declares a type outside of the 1175 // anonymous struct or union. It's okay. 1176 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1177 if (!MemRecord->isAnonymousStructOrUnion() && 1178 MemRecord->getDeclName()) { 1179 // This is a nested type declaration. 1180 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1181 << (int)Record->isUnion(); 1182 Invalid = true; 1183 } 1184 } else { 1185 // We have something that isn't a non-static data 1186 // member. Complain about it. 1187 unsigned DK = diag::err_anonymous_record_bad_member; 1188 if (isa<TypeDecl>(*Mem)) 1189 DK = diag::err_anonymous_record_with_type; 1190 else if (isa<FunctionDecl>(*Mem)) 1191 DK = diag::err_anonymous_record_with_function; 1192 else if (isa<VarDecl>(*Mem)) 1193 DK = diag::err_anonymous_record_with_static; 1194 Diag((*Mem)->getLocation(), DK) 1195 << (int)Record->isUnion(); 1196 Invalid = true; 1197 } 1198 } 1199 } 1200 1201 if (!Record->isUnion() && !Owner->isRecord()) { 1202 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1203 << (int)getLangOptions().CPlusPlus; 1204 Invalid = true; 1205 } 1206 1207 // Create a declaration for this anonymous struct/union. 1208 NamedDecl *Anon = 0; 1209 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1210 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1211 /*IdentifierInfo=*/0, 1212 Context.getTypeDeclType(Record), 1213 /*BitWidth=*/0, /*Mutable=*/false); 1214 Anon->setAccess(AS_public); 1215 if (getLangOptions().CPlusPlus) 1216 FieldCollector->Add(cast<FieldDecl>(Anon)); 1217 } else { 1218 VarDecl::StorageClass SC; 1219 switch (DS.getStorageClassSpec()) { 1220 default: assert(0 && "Unknown storage class!"); 1221 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1222 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1223 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1224 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1225 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1226 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1227 case DeclSpec::SCS_mutable: 1228 // mutable can only appear on non-static class members, so it's always 1229 // an error here 1230 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1231 Invalid = true; 1232 SC = VarDecl::None; 1233 break; 1234 } 1235 1236 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1237 /*IdentifierInfo=*/0, 1238 Context.getTypeDeclType(Record), 1239 SC, DS.getSourceRange().getBegin()); 1240 } 1241 Anon->setImplicit(); 1242 1243 // Add the anonymous struct/union object to the current 1244 // context. We'll be referencing this object when we refer to one of 1245 // its members. 1246 Owner->addDecl(Context, Anon); 1247 1248 // Inject the members of the anonymous struct/union into the owning 1249 // context and into the identifier resolver chain for name lookup 1250 // purposes. 1251 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1252 Invalid = true; 1253 1254 // Mark this as an anonymous struct/union type. Note that we do not 1255 // do this until after we have already checked and injected the 1256 // members of this anonymous struct/union type, because otherwise 1257 // the members could be injected twice: once by DeclContext when it 1258 // builds its lookup table, and once by 1259 // InjectAnonymousStructOrUnionMembers. 1260 Record->setAnonymousStructOrUnion(true); 1261 1262 if (Invalid) 1263 Anon->setInvalidDecl(); 1264 1265 return DeclPtrTy::make(Anon); 1266} 1267 1268 1269/// GetNameForDeclarator - Determine the full declaration name for the 1270/// given Declarator. 1271DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1272 switch (D.getKind()) { 1273 case Declarator::DK_Abstract: 1274 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1275 return DeclarationName(); 1276 1277 case Declarator::DK_Normal: 1278 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1279 return DeclarationName(D.getIdentifier()); 1280 1281 case Declarator::DK_Constructor: { 1282 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1283 Ty = Context.getCanonicalType(Ty); 1284 return Context.DeclarationNames.getCXXConstructorName(Ty); 1285 } 1286 1287 case Declarator::DK_Destructor: { 1288 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1289 Ty = Context.getCanonicalType(Ty); 1290 return Context.DeclarationNames.getCXXDestructorName(Ty); 1291 } 1292 1293 case Declarator::DK_Conversion: { 1294 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1295 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1296 Ty = Context.getCanonicalType(Ty); 1297 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1298 } 1299 1300 case Declarator::DK_Operator: 1301 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1302 return Context.DeclarationNames.getCXXOperatorName( 1303 D.getOverloadedOperator()); 1304 } 1305 1306 assert(false && "Unknown name kind"); 1307 return DeclarationName(); 1308} 1309 1310/// isNearlyMatchingFunction - Determine whether the C++ functions 1311/// Declaration and Definition are "nearly" matching. This heuristic 1312/// is used to improve diagnostics in the case where an out-of-line 1313/// function definition doesn't match any declaration within 1314/// the class or namespace. 1315static bool isNearlyMatchingFunction(ASTContext &Context, 1316 FunctionDecl *Declaration, 1317 FunctionDecl *Definition) { 1318 if (Declaration->param_size() != Definition->param_size()) 1319 return false; 1320 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1321 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1322 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1323 1324 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1325 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1326 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1327 return false; 1328 } 1329 1330 return true; 1331} 1332 1333Sema::DeclPtrTy 1334Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1335 DeclarationName Name = GetNameForDeclarator(D); 1336 1337 // All of these full declarators require an identifier. If it doesn't have 1338 // one, the ParsedFreeStandingDeclSpec action should be used. 1339 if (!Name) { 1340 if (!D.getInvalidType()) // Reject this if we think it is valid. 1341 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1342 diag::err_declarator_need_ident) 1343 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1344 return DeclPtrTy(); 1345 } 1346 1347 // The scope passed in may not be a decl scope. Zip up the scope tree until 1348 // we find one that is. 1349 while ((S->getFlags() & Scope::DeclScope) == 0 || 1350 (S->getFlags() & Scope::TemplateParamScope) != 0) 1351 S = S->getParent(); 1352 1353 DeclContext *DC; 1354 NamedDecl *PrevDecl; 1355 NamedDecl *New; 1356 bool InvalidDecl = false; 1357 1358 QualType R = GetTypeForDeclarator(D, S); 1359 if (R.isNull()) { 1360 InvalidDecl = true; 1361 R = Context.IntTy; 1362 if (IsFunctionDefinition) // int(...) 1363 R = Context.getFunctionType(R, 0, 0, true, 0); 1364 1365 } 1366 1367 // See if this is a redefinition of a variable in the same scope. 1368 if (D.getCXXScopeSpec().isInvalid()) { 1369 DC = CurContext; 1370 PrevDecl = 0; 1371 InvalidDecl = true; 1372 } else if (!D.getCXXScopeSpec().isSet()) { 1373 LookupNameKind NameKind = LookupOrdinaryName; 1374 1375 // If the declaration we're planning to build will be a function 1376 // or object with linkage, then look for another declaration with 1377 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1378 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1379 /* Do nothing*/; 1380 else if (R->isFunctionType()) { 1381 if (CurContext->isFunctionOrMethod()) 1382 NameKind = LookupRedeclarationWithLinkage; 1383 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1384 NameKind = LookupRedeclarationWithLinkage; 1385 1386 DC = CurContext; 1387 PrevDecl = LookupName(S, Name, NameKind, true, 1388 D.getDeclSpec().getStorageClassSpec() != 1389 DeclSpec::SCS_static, 1390 D.getIdentifierLoc()); 1391 } else { // Something like "int foo::x;" 1392 DC = computeDeclContext(D.getCXXScopeSpec()); 1393 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1394 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1395 1396 // C++ 7.3.1.2p2: 1397 // Members (including explicit specializations of templates) of a named 1398 // namespace can also be defined outside that namespace by explicit 1399 // qualification of the name being defined, provided that the entity being 1400 // defined was already declared in the namespace and the definition appears 1401 // after the point of declaration in a namespace that encloses the 1402 // declarations namespace. 1403 // 1404 // Note that we only check the context at this point. We don't yet 1405 // have enough information to make sure that PrevDecl is actually 1406 // the declaration we want to match. For example, given: 1407 // 1408 // class X { 1409 // void f(); 1410 // void f(float); 1411 // }; 1412 // 1413 // void X::f(int) { } // ill-formed 1414 // 1415 // In this case, PrevDecl will point to the overload set 1416 // containing the two f's declared in X, but neither of them 1417 // matches. 1418 1419 // First check whether we named the global scope. 1420 if (isa<TranslationUnitDecl>(DC)) { 1421 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1422 << Name << D.getCXXScopeSpec().getRange(); 1423 } else if (!CurContext->Encloses(DC)) { 1424 // The qualifying scope doesn't enclose the original declaration. 1425 // Emit diagnostic based on current scope. 1426 SourceLocation L = D.getIdentifierLoc(); 1427 SourceRange R = D.getCXXScopeSpec().getRange(); 1428 if (isa<FunctionDecl>(CurContext)) 1429 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1430 else 1431 Diag(L, diag::err_invalid_declarator_scope) 1432 << Name << cast<NamedDecl>(DC) << R; 1433 InvalidDecl = true; 1434 } 1435 } 1436 1437 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1438 // Maybe we will complain about the shadowed template parameter. 1439 InvalidDecl = InvalidDecl 1440 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1441 // Just pretend that we didn't see the previous declaration. 1442 PrevDecl = 0; 1443 } 1444 1445 // In C++, the previous declaration we find might be a tag type 1446 // (class or enum). In this case, the new declaration will hide the 1447 // tag type. Note that this does does not apply if we're declaring a 1448 // typedef (C++ [dcl.typedef]p4). 1449 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1450 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1451 PrevDecl = 0; 1452 1453 bool Redeclaration = false; 1454 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1455 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, 1456 InvalidDecl, Redeclaration); 1457 } else if (R->isFunctionType()) { 1458 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1459 IsFunctionDefinition, InvalidDecl, 1460 Redeclaration); 1461 } else { 1462 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, 1463 InvalidDecl, Redeclaration); 1464 } 1465 1466 if (New == 0) 1467 return DeclPtrTy(); 1468 1469 // If this has an identifier and is not an invalid redeclaration, 1470 // add it to the scope stack. 1471 if (Name && !(Redeclaration && InvalidDecl)) 1472 PushOnScopeChains(New, S); 1473 // If any semantic error occurred, mark the decl as invalid. 1474 if (D.getInvalidType() || InvalidDecl) 1475 New->setInvalidDecl(); 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& InvalidDecl, 1572 bool &Redeclaration) { 1573 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1574 if (D.getCXXScopeSpec().isSet()) { 1575 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1576 << D.getCXXScopeSpec().getRange(); 1577 InvalidDecl = true; 1578 // Pretend we didn't see the scope specifier. 1579 DC = 0; 1580 } 1581 1582 if (getLangOptions().CPlusPlus) { 1583 // Check that there are no default arguments (C++ only). 1584 CheckExtraCXXDefaultArguments(D); 1585 } 1586 1587 DiagnoseFunctionSpecifiers(D); 1588 1589 if (D.getDeclSpec().isThreadSpecified()) 1590 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1591 1592 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1593 if (!NewTD) return 0; 1594 1595 // Handle attributes prior to checking for duplicates in MergeVarDecl 1596 ProcessDeclAttributes(NewTD, D); 1597 // Merge the decl with the existing one if appropriate. If the decl is 1598 // in an outer scope, it isn't the same thing. 1599 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1600 Redeclaration = true; 1601 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1602 InvalidDecl = true; 1603 } 1604 1605 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1606 // then it shall have block scope. 1607 QualType T = NewTD->getUnderlyingType(); 1608 if (T->isVariablyModifiedType()) { 1609 CurFunctionNeedsScopeChecking = true; 1610 1611 if (S->getFnParent() == 0) { 1612 bool SizeIsNegative; 1613 QualType FixedTy = 1614 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1615 if (!FixedTy.isNull()) { 1616 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1617 NewTD->setUnderlyingType(FixedTy); 1618 } else { 1619 if (SizeIsNegative) 1620 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1621 else if (T->isVariableArrayType()) 1622 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1623 else 1624 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1625 InvalidDecl = true; 1626 } 1627 } 1628 } 1629 return NewTD; 1630} 1631 1632/// \brief Determines whether the given declaration is an out-of-scope 1633/// previous declaration. 1634/// 1635/// This routine should be invoked when name lookup has found a 1636/// previous declaration (PrevDecl) that is not in the scope where a 1637/// new declaration by the same name is being introduced. If the new 1638/// declaration occurs in a local scope, previous declarations with 1639/// linkage may still be considered previous declarations (C99 1640/// 6.2.2p4-5, C++ [basic.link]p6). 1641/// 1642/// \param PrevDecl the previous declaration found by name 1643/// lookup 1644/// 1645/// \param DC the context in which the new declaration is being 1646/// declared. 1647/// 1648/// \returns true if PrevDecl is an out-of-scope previous declaration 1649/// for a new delcaration with the same name. 1650static bool 1651isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1652 ASTContext &Context) { 1653 if (!PrevDecl) 1654 return 0; 1655 1656 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1657 // case we need to check each of the overloaded functions. 1658 if (!PrevDecl->hasLinkage()) 1659 return false; 1660 1661 if (Context.getLangOptions().CPlusPlus) { 1662 // C++ [basic.link]p6: 1663 // If there is a visible declaration of an entity with linkage 1664 // having the same name and type, ignoring entities declared 1665 // outside the innermost enclosing namespace scope, the block 1666 // scope declaration declares that same entity and receives the 1667 // linkage of the previous declaration. 1668 DeclContext *OuterContext = DC->getLookupContext(); 1669 if (!OuterContext->isFunctionOrMethod()) 1670 // This rule only applies to block-scope declarations. 1671 return false; 1672 else { 1673 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1674 if (PrevOuterContext->isRecord()) 1675 // We found a member function: ignore it. 1676 return false; 1677 else { 1678 // Find the innermost enclosing namespace for the new and 1679 // previous declarations. 1680 while (!OuterContext->isFileContext()) 1681 OuterContext = OuterContext->getParent(); 1682 while (!PrevOuterContext->isFileContext()) 1683 PrevOuterContext = PrevOuterContext->getParent(); 1684 1685 // The previous declaration is in a different namespace, so it 1686 // isn't the same function. 1687 if (OuterContext->getPrimaryContext() != 1688 PrevOuterContext->getPrimaryContext()) 1689 return false; 1690 } 1691 } 1692 } 1693 1694 return true; 1695} 1696 1697NamedDecl* 1698Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1699 QualType R,NamedDecl* PrevDecl, bool& InvalidDecl, 1700 bool &Redeclaration) { 1701 DeclarationName Name = GetNameForDeclarator(D); 1702 1703 // Check that there are no default arguments (C++ only). 1704 if (getLangOptions().CPlusPlus) 1705 CheckExtraCXXDefaultArguments(D); 1706 1707 VarDecl *NewVD; 1708 VarDecl::StorageClass SC; 1709 switch (D.getDeclSpec().getStorageClassSpec()) { 1710 default: assert(0 && "Unknown storage class!"); 1711 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1712 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1713 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1714 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1715 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1716 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1717 case DeclSpec::SCS_mutable: 1718 // mutable can only appear on non-static class members, so it's always 1719 // an error here 1720 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1721 InvalidDecl = true; 1722 SC = VarDecl::None; 1723 break; 1724 } 1725 1726 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1727 if (!II) { 1728 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1729 << Name.getAsString(); 1730 return 0; 1731 } 1732 1733 DiagnoseFunctionSpecifiers(D); 1734 1735 if (!DC->isRecord() && S->getFnParent() == 0) { 1736 // C99 6.9p2: The storage-class specifiers auto and register shall not 1737 // appear in the declaration specifiers in an external declaration. 1738 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1739 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1740 InvalidDecl = true; 1741 } 1742 } 1743 if (DC->isRecord() && !CurContext->isRecord()) { 1744 // This is an out-of-line definition of a static data member. 1745 if (SC == VarDecl::Static) { 1746 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1747 diag::err_static_out_of_line) 1748 << CodeModificationHint::CreateRemoval( 1749 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1750 } else if (SC == VarDecl::None) 1751 SC = VarDecl::Static; 1752 } 1753 1754 // The variable can not 1755 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1756 II, R, SC, 1757 // FIXME: Move to DeclGroup... 1758 D.getDeclSpec().getSourceRange().getBegin()); 1759 1760 if (D.getDeclSpec().isThreadSpecified()) { 1761 if (NewVD->hasLocalStorage()) 1762 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1763 else if (!Context.Target.isTLSSupported()) 1764 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1765 else 1766 NewVD->setThreadSpecified(true); 1767 } 1768 1769 // Set the lexical context. If the declarator has a C++ scope specifier, the 1770 // lexical context will be different from the semantic context. 1771 NewVD->setLexicalDeclContext(CurContext); 1772 1773 // Handle attributes prior to checking for duplicates in MergeVarDecl 1774 ProcessDeclAttributes(NewVD, D); 1775 1776 // Handle GNU asm-label extension (encoded as an attribute). 1777 if (Expr *E = (Expr*) D.getAsmLabel()) { 1778 // The parser guarantees this is a string. 1779 StringLiteral *SE = cast<StringLiteral>(E); 1780 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1781 SE->getByteLength()))); 1782 } 1783 1784 // If name lookup finds a previous declaration that is not in the 1785 // same scope as the new declaration, this may still be an 1786 // acceptable redeclaration. 1787 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1788 !(NewVD->hasLinkage() && 1789 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1790 PrevDecl = 0; 1791 1792 // Merge the decl with the existing one if appropriate. 1793 if (PrevDecl) { 1794 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1795 // The user tried to define a non-static data member 1796 // out-of-line (C++ [dcl.meaning]p1). 1797 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1798 << D.getCXXScopeSpec().getRange(); 1799 PrevDecl = 0; 1800 InvalidDecl = true; 1801 } 1802 } else if (D.getCXXScopeSpec().isSet()) { 1803 // No previous declaration in the qualifying scope. 1804 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1805 << Name << D.getCXXScopeSpec().getRange(); 1806 InvalidDecl = true; 1807 } 1808 1809 if (CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration)) 1810 InvalidDecl = true; 1811 1812 // If this is a locally-scoped extern C variable, update the map of 1813 // such variables. 1814 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1815 !InvalidDecl) 1816 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1817 1818 return NewVD; 1819} 1820 1821/// \brief Perform semantic checking on a newly-created variable 1822/// declaration. 1823/// 1824/// This routine performs all of the type-checking required for a 1825/// variable declaration once it has been build. It is used both to 1826/// check variables after they have been parsed and their declarators 1827/// have been translated into a declaration, and to check 1828/// 1829/// \returns true if an error was encountered, false otherwise. 1830bool Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1831 bool &Redeclaration) { 1832 bool Invalid = false; 1833 1834 QualType T = NewVD->getType(); 1835 1836 if (T->isObjCInterfaceType()) { 1837 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1838 Invalid = true; 1839 } 1840 1841 // The variable can not have an abstract class type. 1842 if (RequireNonAbstractType(NewVD->getLocation(), T, 1843 diag::err_abstract_type_in_decl, 1844 AbstractVariableType)) 1845 Invalid = true; 1846 1847 // Emit an error if an address space was applied to decl with local storage. 1848 // This includes arrays of objects with address space qualifiers, but not 1849 // automatic variables that point to other address spaces. 1850 // ISO/IEC TR 18037 S5.1.2 1851 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1852 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1853 Invalid = true; 1854 } 1855 1856 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1857 && !NewVD->hasAttr<BlocksAttr>()) 1858 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1859 1860 bool isVM = T->isVariablyModifiedType(); 1861 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1862 CurFunctionNeedsScopeChecking = true; 1863 1864 if ((isVM && NewVD->hasLinkage()) || 1865 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1866 bool SizeIsNegative; 1867 QualType FixedTy = 1868 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1869 if (!FixedTy.isNull()) { 1870 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1871 NewVD->setType(FixedTy); 1872 } else if (T->isVariableArrayType()) { 1873 Invalid = true; 1874 1875 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1876 // FIXME: This won't give the correct result for 1877 // int a[10][n]; 1878 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1879 1880 if (NewVD->isFileVarDecl()) 1881 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1882 << SizeRange; 1883 else if (NewVD->getStorageClass() == VarDecl::Static) 1884 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1885 << SizeRange; 1886 else 1887 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1888 << SizeRange; 1889 } else { 1890 Invalid = true; 1891 1892 if (NewVD->isFileVarDecl()) 1893 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1894 else 1895 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1896 } 1897 } 1898 1899 if (!PrevDecl && NewVD->isExternC(Context)) { 1900 // Since we did not find anything by this name and we're declaring 1901 // an extern "C" variable, look for a non-visible extern "C" 1902 // declaration with the same name. 1903 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1904 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1905 if (Pos != LocallyScopedExternalDecls.end()) 1906 PrevDecl = Pos->second; 1907 } 1908 1909 if (!Invalid && T->isVoidType() && !NewVD->hasExternalStorage()) { 1910 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1911 << T; 1912 Invalid = true; 1913 } 1914 1915 if (PrevDecl) { 1916 Redeclaration = true; 1917 if (MergeVarDecl(NewVD, PrevDecl)) 1918 Invalid = true; 1919 } 1920 1921 return NewVD->isInvalidDecl() || Invalid; 1922} 1923 1924NamedDecl* 1925Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1926 QualType R, NamedDecl* PrevDecl, 1927 bool IsFunctionDefinition, 1928 bool& InvalidDecl, bool &Redeclaration) { 1929 assert(R.getTypePtr()->isFunctionType()); 1930 1931 DeclarationName Name = GetNameForDeclarator(D); 1932 FunctionDecl::StorageClass SC = FunctionDecl::None; 1933 switch (D.getDeclSpec().getStorageClassSpec()) { 1934 default: assert(0 && "Unknown storage class!"); 1935 case DeclSpec::SCS_auto: 1936 case DeclSpec::SCS_register: 1937 case DeclSpec::SCS_mutable: 1938 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1939 diag::err_typecheck_sclass_func); 1940 InvalidDecl = true; 1941 break; 1942 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1943 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1944 case DeclSpec::SCS_static: { 1945 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1946 // C99 6.7.1p5: 1947 // The declaration of an identifier for a function that has 1948 // block scope shall have no explicit storage-class specifier 1949 // other than extern 1950 // See also (C++ [dcl.stc]p4). 1951 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1952 diag::err_static_block_func); 1953 SC = FunctionDecl::None; 1954 } else 1955 SC = FunctionDecl::Static; 1956 break; 1957 } 1958 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1959 } 1960 1961 if (D.getDeclSpec().isThreadSpecified()) 1962 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1963 1964 bool isInline = D.getDeclSpec().isInlineSpecified(); 1965 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1966 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1967 1968 // Check that the return type is not an abstract class type. 1969 // For record types, this is done by the AbstractClassUsageDiagnoser once 1970 // the class has been completely parsed. 1971 if (!DC->isRecord() && 1972 RequireNonAbstractType(D.getIdentifierLoc(), 1973 R->getAsFunctionType()->getResultType(), 1974 diag::err_abstract_type_in_decl, 1975 AbstractReturnType)) 1976 InvalidDecl = true; 1977 1978 // Do not allow returning a objc interface by-value. 1979 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1980 Diag(D.getIdentifierLoc(), 1981 diag::err_object_cannot_be_passed_returned_by_value) << 0 1982 << R->getAsFunctionType()->getResultType(); 1983 InvalidDecl = true; 1984 } 1985 1986 bool isVirtualOkay = false; 1987 FunctionDecl *NewFD; 1988 if (D.getKind() == Declarator::DK_Constructor) { 1989 // This is a C++ constructor declaration. 1990 assert(DC->isRecord() && 1991 "Constructors can only be declared in a member context"); 1992 1993 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1994 1995 // Create the new declaration 1996 NewFD = CXXConstructorDecl::Create(Context, 1997 cast<CXXRecordDecl>(DC), 1998 D.getIdentifierLoc(), Name, R, 1999 isExplicit, isInline, 2000 /*isImplicitlyDeclared=*/false); 2001 2002 if (InvalidDecl) 2003 NewFD->setInvalidDecl(); 2004 } else if (D.getKind() == Declarator::DK_Destructor) { 2005 // This is a C++ destructor declaration. 2006 if (DC->isRecord()) { 2007 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 2008 2009 NewFD = CXXDestructorDecl::Create(Context, 2010 cast<CXXRecordDecl>(DC), 2011 D.getIdentifierLoc(), Name, R, 2012 isInline, 2013 /*isImplicitlyDeclared=*/false); 2014 2015 if (InvalidDecl) 2016 NewFD->setInvalidDecl(); 2017 2018 isVirtualOkay = true; 2019 } else { 2020 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2021 2022 // Create a FunctionDecl to satisfy the function definition parsing 2023 // code path. 2024 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2025 Name, R, SC, isInline, 2026 /*hasPrototype=*/true, 2027 // FIXME: Move to DeclGroup... 2028 D.getDeclSpec().getSourceRange().getBegin()); 2029 InvalidDecl = true; 2030 NewFD->setInvalidDecl(); 2031 } 2032 } else if (D.getKind() == Declarator::DK_Conversion) { 2033 if (!DC->isRecord()) { 2034 Diag(D.getIdentifierLoc(), 2035 diag::err_conv_function_not_member); 2036 return 0; 2037 } else { 2038 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 2039 2040 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2041 D.getIdentifierLoc(), Name, R, 2042 isInline, isExplicit); 2043 2044 if (InvalidDecl) 2045 NewFD->setInvalidDecl(); 2046 2047 isVirtualOkay = true; 2048 } 2049 } else if (DC->isRecord()) { 2050 // This is a C++ method declaration. 2051 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2052 D.getIdentifierLoc(), Name, R, 2053 (SC == FunctionDecl::Static), isInline); 2054 2055 isVirtualOkay = (SC != FunctionDecl::Static); 2056 } else { 2057 // Determine whether the function was written with a 2058 // prototype. This true when: 2059 // - we're in C++ (where every function has a prototype), 2060 // - there is a prototype in the declarator, or 2061 // - the type R of the function is some kind of typedef or other reference 2062 // to a type name (which eventually refers to a function type). 2063 bool HasPrototype = 2064 getLangOptions().CPlusPlus || 2065 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2066 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2067 2068 NewFD = FunctionDecl::Create(Context, DC, 2069 D.getIdentifierLoc(), 2070 Name, R, SC, isInline, HasPrototype, 2071 // FIXME: Move to DeclGroup... 2072 D.getDeclSpec().getSourceRange().getBegin()); 2073 } 2074 2075 // Set the lexical context. If the declarator has a C++ 2076 // scope specifier, the lexical context will be different 2077 // from the semantic context. 2078 NewFD->setLexicalDeclContext(CurContext); 2079 2080 // C++ [dcl.fct.spec]p5: 2081 // The virtual specifier shall only be used in declarations of 2082 // nonstatic class member functions that appear within a 2083 // member-specification of a class declaration; see 10.3. 2084 // 2085 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2086 // function is also virtual if it overrides an already virtual 2087 // function. This is important to do here because it's part of the 2088 // declaration. 2089 if (isVirtual && !InvalidDecl) { 2090 if (!isVirtualOkay) { 2091 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2092 diag::err_virtual_non_function); 2093 } else if (!CurContext->isRecord()) { 2094 // 'virtual' was specified outside of the class. 2095 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2096 << CodeModificationHint::CreateRemoval( 2097 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2098 } else { 2099 // Okay: Add virtual to the method. 2100 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2101 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2102 CurClass->setAggregate(false); 2103 CurClass->setPOD(false); 2104 CurClass->setPolymorphic(true); 2105 CurClass->setHasTrivialConstructor(false); 2106 } 2107 } 2108 2109 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2110 !CurContext->isRecord()) { 2111 // C++ [class.static]p1: 2112 // A data or function member of a class may be declared static 2113 // in a class definition, in which case it is a static member of 2114 // the class. 2115 2116 // Complain about the 'static' specifier if it's on an out-of-line 2117 // member function definition. 2118 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2119 diag::err_static_out_of_line) 2120 << CodeModificationHint::CreateRemoval( 2121 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2122 } 2123 2124 // Handle GNU asm-label extension (encoded as an attribute). 2125 if (Expr *E = (Expr*) D.getAsmLabel()) { 2126 // The parser guarantees this is a string. 2127 StringLiteral *SE = cast<StringLiteral>(E); 2128 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2129 SE->getByteLength()))); 2130 } 2131 2132 // Copy the parameter declarations from the declarator D to 2133 // the function declaration NewFD, if they are available. 2134 if (D.getNumTypeObjects() > 0) { 2135 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2136 2137 // Create Decl objects for each parameter, adding them to the 2138 // FunctionDecl. 2139 llvm::SmallVector<ParmVarDecl*, 16> Params; 2140 2141 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2142 // function that takes no arguments, not a function that takes a 2143 // single void argument. 2144 // We let through "const void" here because Sema::GetTypeForDeclarator 2145 // already checks for that case. 2146 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2147 FTI.ArgInfo[0].Param && 2148 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2149 // empty arg list, don't push any params. 2150 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2151 2152 // In C++, the empty parameter-type-list must be spelled "void"; a 2153 // typedef of void is not permitted. 2154 if (getLangOptions().CPlusPlus && 2155 Param->getType().getUnqualifiedType() != Context.VoidTy) { 2156 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2157 } 2158 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2159 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2160 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2161 } 2162 2163 NewFD->setParams(Context, &Params[0], Params.size()); 2164 } else if (R->getAsTypedefType()) { 2165 // When we're declaring a function with a typedef, as in the 2166 // following example, we'll need to synthesize (unnamed) 2167 // parameters for use in the declaration. 2168 // 2169 // @code 2170 // typedef void fn(int); 2171 // fn f; 2172 // @endcode 2173 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 2174 if (!FT) { 2175 // This is a typedef of a function with no prototype, so we 2176 // don't need to do anything. 2177 } else if ((FT->getNumArgs() == 0) || 2178 (FT->getNumArgs() == 1 && !FT->isVariadic() && 2179 FT->getArgType(0)->isVoidType())) { 2180 // This is a zero-argument function. We don't need to do anything. 2181 } else { 2182 // Synthesize a parameter for each argument type. 2183 llvm::SmallVector<ParmVarDecl*, 16> Params; 2184 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 2185 ArgType != FT->arg_type_end(); ++ArgType) { 2186 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2187 SourceLocation(), 0, 2188 *ArgType, VarDecl::None, 2189 0); 2190 Param->setImplicit(); 2191 Params.push_back(Param); 2192 } 2193 2194 NewFD->setParams(Context, &Params[0], Params.size()); 2195 } 2196 } 2197 2198 // If name lookup finds a previous declaration that is not in the 2199 // same scope as the new declaration, this may still be an 2200 // acceptable redeclaration. 2201 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2202 !(NewFD->hasLinkage() && 2203 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2204 PrevDecl = 0; 2205 2206 // FIXME: We need to determine whether the GNU inline attribute will 2207 // be applied to this function declaration, since it affects 2208 // declaration merging. This hack will go away when the FIXME below 2209 // is resolved, since we should be putting *all* attributes onto the 2210 // declaration now. 2211 for (const AttributeList *Attr = D.getDeclSpec().getAttributes(); 2212 Attr; Attr = Attr->getNext()) { 2213 if (Attr->getKind() == AttributeList::AT_gnu_inline) { 2214 NewFD->addAttr(::new (Context) GNUInlineAttr()); 2215 break; 2216 } 2217 } 2218 2219 // Perform semantic checking on the function declaration. 2220 bool OverloadableAttrRequired = false; // FIXME: HACK! 2221 if (CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2222 /*FIXME:*/OverloadableAttrRequired)) 2223 InvalidDecl = true; 2224 2225 if (D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2226 // An out-of-line member function declaration must also be a 2227 // definition (C++ [dcl.meaning]p1). 2228 if (!IsFunctionDefinition) { 2229 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2230 << D.getCXXScopeSpec().getRange(); 2231 InvalidDecl = true; 2232 } else if (!Redeclaration) { 2233 // The user tried to provide an out-of-line definition for a 2234 // function that is a member of a class or namespace, but there 2235 // was no such member function declared (C++ [class.mfct]p2, 2236 // C++ [namespace.memdef]p2). For example: 2237 // 2238 // class X { 2239 // void f() const; 2240 // }; 2241 // 2242 // void X::f() { } // ill-formed 2243 // 2244 // Complain about this problem, and attempt to suggest close 2245 // matches (e.g., those that differ only in cv-qualifiers and 2246 // whether the parameter types are references). 2247 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2248 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2249 InvalidDecl = true; 2250 2251 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2252 true); 2253 assert(!Prev.isAmbiguous() && 2254 "Cannot have an ambiguity in previous-declaration lookup"); 2255 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2256 Func != FuncEnd; ++Func) { 2257 if (isa<FunctionDecl>(*Func) && 2258 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2259 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2260 } 2261 2262 PrevDecl = 0; 2263 } 2264 } 2265 2266 // Handle attributes. We need to have merged decls when handling attributes 2267 // (for example to check for conflicts, etc). 2268 // FIXME: This needs to happen before we merge declarations. Then, 2269 // let attribute merging cope with attribute conflicts. 2270 ProcessDeclAttributes(NewFD, D); 2271 AddKnownFunctionAttributes(NewFD); 2272 2273 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2274 // If a function name is overloadable in C, then every function 2275 // with that name must be marked "overloadable". 2276 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2277 << Redeclaration << NewFD; 2278 if (PrevDecl) 2279 Diag(PrevDecl->getLocation(), 2280 diag::note_attribute_overloadable_prev_overload); 2281 NewFD->addAttr(::new (Context) OverloadableAttr()); 2282 } 2283 2284 // If this is a locally-scoped extern C function, update the 2285 // map of such names. 2286 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2287 && !InvalidDecl) 2288 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2289 2290 return NewFD; 2291} 2292 2293/// \brief Perform semantic checking of a new function declaration. 2294/// 2295/// Performs semantic analysis of the new function declaration 2296/// NewFD. This routine performs all semantic checking that does not 2297/// require the actual declarator involved in the declaration, and is 2298/// used both for the declaration of functions as they are parsed 2299/// (called via ActOnDeclarator) and for the declaration of functions 2300/// that have been instantiated via C++ template instantiation (called 2301/// via InstantiateDecl). 2302/// 2303/// \returns true if there was an error, false otherwise. 2304bool Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2305 bool &Redeclaration, 2306 bool &OverloadableAttrRequired) { 2307 bool InvalidDecl = false; 2308 2309 // Semantic checking for this function declaration (in isolation). 2310 if (getLangOptions().CPlusPlus) { 2311 // C++-specific checks. 2312 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 2313 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 2314 else if (isa<CXXDestructorDecl>(NewFD)) { 2315 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2316 Record->setUserDeclaredDestructor(true); 2317 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2318 // user-defined destructor. 2319 Record->setPOD(false); 2320 2321 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2322 // declared destructor. 2323 Record->setHasTrivialDestructor(false); 2324 } else if (CXXConversionDecl *Conversion 2325 = dyn_cast<CXXConversionDecl>(NewFD)) 2326 ActOnConversionDeclarator(Conversion); 2327 2328 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2329 if (NewFD->isOverloadedOperator() && 2330 CheckOverloadedOperatorDeclaration(NewFD)) 2331 InvalidDecl = true; 2332 } 2333 2334 // C99 6.7.4p6: 2335 // [... ] For a function with external linkage, the following 2336 // restrictions apply: [...] If all of the file scope declarations 2337 // for a function in a translation unit include the inline 2338 // function specifier without extern, then the definition in that 2339 // translation unit is an inline definition. An inline definition 2340 // does not provide an external definition for the function, and 2341 // does not forbid an external definition in another translation 2342 // unit. 2343 // 2344 // Here we determine whether this function, in isolation, would be a 2345 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2346 // previous declarations. 2347 if (NewFD->isInline() && 2348 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2349 bool GNUInline = NewFD->hasAttr<GNUInlineAttr>() || 2350 (PrevDecl && PrevDecl->hasAttr<GNUInlineAttr>()); 2351 if (GNUInline || (!getLangOptions().CPlusPlus && !getLangOptions().C99)) { 2352 // GNU "extern inline" is the same as "inline" in C99. 2353 if (NewFD->getStorageClass() == FunctionDecl::Extern) 2354 NewFD->setC99InlineDefinition(true); 2355 } else if (getLangOptions().C99 && 2356 NewFD->getStorageClass() == FunctionDecl::None) 2357 NewFD->setC99InlineDefinition(true); 2358 } 2359 2360 // Check for a previous declaration of this name. 2361 if (!PrevDecl && NewFD->isExternC(Context)) { 2362 // Since we did not find anything by this name and we're declaring 2363 // an extern "C" function, look for a non-visible extern "C" 2364 // declaration with the same name. 2365 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2366 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2367 if (Pos != LocallyScopedExternalDecls.end()) 2368 PrevDecl = Pos->second; 2369 } 2370 2371 // Merge or overload the declaration with an existing declaration of 2372 // the same name, if appropriate. 2373 if (PrevDecl) { 2374 // Determine whether NewFD is an overload of PrevDecl or 2375 // a declaration that requires merging. If it's an overload, 2376 // there's no more work to do here; we'll just add the new 2377 // function to the scope. 2378 OverloadedFunctionDecl::function_iterator MatchedDecl; 2379 2380 if (!getLangOptions().CPlusPlus && 2381 AllowOverloadingOfFunction(PrevDecl, Context)) { 2382 OverloadableAttrRequired = true; 2383 2384 // Functions marked "overloadable" must have a prototype (that 2385 // we can't get through declaration merging). 2386 if (!NewFD->getType()->getAsFunctionProtoType()) { 2387 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2388 << NewFD; 2389 InvalidDecl = true; 2390 Redeclaration = true; 2391 2392 // Turn this into a variadic function with no parameters. 2393 QualType R = Context.getFunctionType( 2394 NewFD->getType()->getAsFunctionType()->getResultType(), 2395 0, 0, true, 0); 2396 NewFD->setType(R); 2397 } 2398 } 2399 2400 if (PrevDecl && 2401 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2402 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2403 Redeclaration = true; 2404 Decl *OldDecl = PrevDecl; 2405 2406 // If PrevDecl was an overloaded function, extract the 2407 // FunctionDecl that matched. 2408 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2409 OldDecl = *MatchedDecl; 2410 2411 // NewFD and OldDecl represent declarations that need to be 2412 // merged. 2413 if (MergeFunctionDecl(NewFD, OldDecl)) 2414 InvalidDecl = true; 2415 2416 if (!InvalidDecl) 2417 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2418 } 2419 } 2420 2421 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) { 2422 // In C++, check default arguments now that we have merged decls. Unless 2423 // the lexical context is the class, because in this case this is done 2424 // during delayed parsing anyway. 2425 CheckCXXDefaultArguments(NewFD); 2426 } 2427 2428 return InvalidDecl || NewFD->isInvalidDecl(); 2429} 2430 2431bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2432 // FIXME: Need strict checking. In C89, we need to check for 2433 // any assignment, increment, decrement, function-calls, or 2434 // commas outside of a sizeof. In C99, it's the same list, 2435 // except that the aforementioned are allowed in unevaluated 2436 // expressions. Everything else falls under the 2437 // "may accept other forms of constant expressions" exception. 2438 // (We never end up here for C++, so the constant expression 2439 // rules there don't matter.) 2440 if (Init->isConstantInitializer(Context)) 2441 return false; 2442 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2443 << Init->getSourceRange(); 2444 return true; 2445} 2446 2447void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2448 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2449} 2450 2451/// AddInitializerToDecl - Adds the initializer Init to the 2452/// declaration dcl. If DirectInit is true, this is C++ direct 2453/// initialization rather than copy initialization. 2454void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2455 Decl *RealDecl = dcl.getAs<Decl>(); 2456 // If there is no declaration, there was an error parsing it. Just ignore 2457 // the initializer. 2458 if (RealDecl == 0) 2459 return; 2460 2461 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2462 // With declarators parsed the way they are, the parser cannot 2463 // distinguish between a normal initializer and a pure-specifier. 2464 // Thus this grotesque test. 2465 IntegerLiteral *IL; 2466 Expr *Init = static_cast<Expr *>(init.get()); 2467 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2468 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2469 if (Method->isVirtual()) { 2470 Method->setPure(); 2471 2472 // A class is abstract if at least one function is pure virtual. 2473 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2474 } else if (!Method->isInvalidDecl()) { 2475 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2476 << Method->getDeclName() << Init->getSourceRange(); 2477 Method->setInvalidDecl(); 2478 } 2479 } else { 2480 Diag(Method->getLocation(), diag::err_member_function_initialization) 2481 << Method->getDeclName() << Init->getSourceRange(); 2482 Method->setInvalidDecl(); 2483 } 2484 return; 2485 } 2486 2487 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2488 if (!VDecl) { 2489 if (getLangOptions().CPlusPlus && 2490 RealDecl->getLexicalDeclContext()->isRecord() && 2491 isa<NamedDecl>(RealDecl)) 2492 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2493 << cast<NamedDecl>(RealDecl)->getDeclName(); 2494 else 2495 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2496 RealDecl->setInvalidDecl(); 2497 return; 2498 } 2499 2500 if (!VDecl->getType()->isArrayType() && 2501 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2502 diag::err_typecheck_decl_incomplete_type)) { 2503 RealDecl->setInvalidDecl(); 2504 return; 2505 } 2506 2507 const VarDecl *Def = 0; 2508 if (VDecl->getDefinition(Def)) { 2509 Diag(VDecl->getLocation(), diag::err_redefinition) 2510 << VDecl->getDeclName(); 2511 Diag(Def->getLocation(), diag::note_previous_definition); 2512 VDecl->setInvalidDecl(); 2513 return; 2514 } 2515 2516 // Take ownership of the expression, now that we're sure we have somewhere 2517 // to put it. 2518 Expr *Init = static_cast<Expr *>(init.release()); 2519 assert(Init && "missing initializer"); 2520 2521 // Get the decls type and save a reference for later, since 2522 // CheckInitializerTypes may change it. 2523 QualType DclT = VDecl->getType(), SavT = DclT; 2524 if (VDecl->isBlockVarDecl()) { 2525 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2526 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2527 VDecl->setInvalidDecl(); 2528 } else if (!VDecl->isInvalidDecl()) { 2529 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2530 VDecl->getDeclName(), DirectInit)) 2531 VDecl->setInvalidDecl(); 2532 2533 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2534 // Don't check invalid declarations to avoid emitting useless diagnostics. 2535 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2536 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2537 CheckForConstantInitializer(Init, DclT); 2538 } 2539 } 2540 } else if (VDecl->isStaticDataMember() && 2541 VDecl->getLexicalDeclContext()->isRecord()) { 2542 // This is an in-class initialization for a static data member, e.g., 2543 // 2544 // struct S { 2545 // static const int value = 17; 2546 // }; 2547 2548 // Attach the initializer 2549 VDecl->setInit(Init); 2550 2551 // C++ [class.mem]p4: 2552 // A member-declarator can contain a constant-initializer only 2553 // if it declares a static member (9.4) of const integral or 2554 // const enumeration type, see 9.4.2. 2555 QualType T = VDecl->getType(); 2556 if (!T->isDependentType() && 2557 (!Context.getCanonicalType(T).isConstQualified() || 2558 !T->isIntegralType())) { 2559 Diag(VDecl->getLocation(), diag::err_member_initialization) 2560 << VDecl->getDeclName() << Init->getSourceRange(); 2561 VDecl->setInvalidDecl(); 2562 } else { 2563 // C++ [class.static.data]p4: 2564 // If a static data member is of const integral or const 2565 // enumeration type, its declaration in the class definition 2566 // can specify a constant-initializer which shall be an 2567 // integral constant expression (5.19). 2568 if (!Init->isTypeDependent() && 2569 !Init->getType()->isIntegralType()) { 2570 // We have a non-dependent, non-integral or enumeration type. 2571 Diag(Init->getSourceRange().getBegin(), 2572 diag::err_in_class_initializer_non_integral_type) 2573 << Init->getType() << Init->getSourceRange(); 2574 VDecl->setInvalidDecl(); 2575 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2576 // Check whether the expression is a constant expression. 2577 llvm::APSInt Value; 2578 SourceLocation Loc; 2579 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2580 Diag(Loc, diag::err_in_class_initializer_non_constant) 2581 << Init->getSourceRange(); 2582 VDecl->setInvalidDecl(); 2583 } else if (!VDecl->getType()->isDependentType()) 2584 ImpCastExprToType(Init, VDecl->getType()); 2585 } 2586 } 2587 } else if (VDecl->isFileVarDecl()) { 2588 if (VDecl->getStorageClass() == VarDecl::Extern) 2589 Diag(VDecl->getLocation(), diag::warn_extern_init); 2590 if (!VDecl->isInvalidDecl()) 2591 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2592 VDecl->getDeclName(), DirectInit)) 2593 VDecl->setInvalidDecl(); 2594 2595 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2596 // Don't check invalid declarations to avoid emitting useless diagnostics. 2597 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2598 // C99 6.7.8p4. All file scoped initializers need to be constant. 2599 CheckForConstantInitializer(Init, DclT); 2600 } 2601 } 2602 // If the type changed, it means we had an incomplete type that was 2603 // completed by the initializer. For example: 2604 // int ary[] = { 1, 3, 5 }; 2605 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2606 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2607 VDecl->setType(DclT); 2608 Init->setType(DclT); 2609 } 2610 2611 // Attach the initializer to the decl. 2612 VDecl->setInit(Init); 2613 2614 // If the previous declaration of VDecl was a tentative definition, 2615 // remove it from the set of tentative definitions. 2616 if (VDecl->getPreviousDeclaration() && 2617 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2618 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2619 = TentativeDefinitions.find(VDecl->getDeclName()); 2620 assert(Pos != TentativeDefinitions.end() && 2621 "Unrecorded tentative definition?"); 2622 TentativeDefinitions.erase(Pos); 2623 } 2624 2625 return; 2626} 2627 2628void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2629 Decl *RealDecl = dcl.getAs<Decl>(); 2630 2631 // If there is no declaration, there was an error parsing it. Just ignore it. 2632 if (RealDecl == 0) 2633 return; 2634 2635 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2636 QualType Type = Var->getType(); 2637 2638 // Record tentative definitions. 2639 if (Var->isTentativeDefinition(Context)) 2640 TentativeDefinitions[Var->getDeclName()] = Var; 2641 2642 // C++ [dcl.init.ref]p3: 2643 // The initializer can be omitted for a reference only in a 2644 // parameter declaration (8.3.5), in the declaration of a 2645 // function return type, in the declaration of a class member 2646 // within its class declaration (9.2), and where the extern 2647 // specifier is explicitly used. 2648 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2649 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2650 << Var->getDeclName() 2651 << SourceRange(Var->getLocation(), Var->getLocation()); 2652 Var->setInvalidDecl(); 2653 return; 2654 } 2655 2656 // C++ [dcl.init]p9: 2657 // 2658 // If no initializer is specified for an object, and the object 2659 // is of (possibly cv-qualified) non-POD class type (or array 2660 // thereof), the object shall be default-initialized; if the 2661 // object is of const-qualified type, the underlying class type 2662 // shall have a user-declared default constructor. 2663 if (getLangOptions().CPlusPlus) { 2664 QualType InitType = Type; 2665 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2666 InitType = Array->getElementType(); 2667 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2668 CXXRecordDecl *RD = 2669 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2670 CXXConstructorDecl *Constructor = 0; 2671 if (!RequireCompleteType(Var->getLocation(), InitType, 2672 diag::err_invalid_incomplete_type_use)) 2673 Constructor 2674 = PerformInitializationByConstructor(InitType, 0, 0, 2675 Var->getLocation(), 2676 SourceRange(Var->getLocation(), 2677 Var->getLocation()), 2678 Var->getDeclName(), 2679 IK_Default); 2680 if (!Constructor) 2681 Var->setInvalidDecl(); 2682 else if (!RD->hasTrivialConstructor()) 2683 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2684 } 2685 } 2686 2687#if 0 2688 // FIXME: Temporarily disabled because we are not properly parsing 2689 // linkage specifications on declarations, e.g., 2690 // 2691 // extern "C" const CGPoint CGPointerZero; 2692 // 2693 // C++ [dcl.init]p9: 2694 // 2695 // If no initializer is specified for an object, and the 2696 // object is of (possibly cv-qualified) non-POD class type (or 2697 // array thereof), the object shall be default-initialized; if 2698 // the object is of const-qualified type, the underlying class 2699 // type shall have a user-declared default 2700 // constructor. Otherwise, if no initializer is specified for 2701 // an object, the object and its subobjects, if any, have an 2702 // indeterminate initial value; if the object or any of its 2703 // subobjects are of const-qualified type, the program is 2704 // ill-formed. 2705 // 2706 // This isn't technically an error in C, so we don't diagnose it. 2707 // 2708 // FIXME: Actually perform the POD/user-defined default 2709 // constructor check. 2710 if (getLangOptions().CPlusPlus && 2711 Context.getCanonicalType(Type).isConstQualified() && 2712 !Var->hasExternalStorage()) 2713 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2714 << Var->getName() 2715 << SourceRange(Var->getLocation(), Var->getLocation()); 2716#endif 2717 } 2718} 2719 2720Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2721 unsigned NumDecls) { 2722 llvm::SmallVector<Decl*, 8> Decls; 2723 2724 for (unsigned i = 0; i != NumDecls; ++i) 2725 if (Decl *D = Group[i].getAs<Decl>()) 2726 Decls.push_back(D); 2727 2728 // Perform semantic analysis that depends on having fully processed both 2729 // the declarator and initializer. 2730 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2731 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2732 if (!IDecl) 2733 continue; 2734 QualType T = IDecl->getType(); 2735 2736 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2737 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2738 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2739 if (!IDecl->isInvalidDecl() && 2740 RequireCompleteType(IDecl->getLocation(), T, 2741 diag::err_typecheck_decl_incomplete_type)) 2742 IDecl->setInvalidDecl(); 2743 } 2744 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2745 // object that has file scope without an initializer, and without a 2746 // storage-class specifier or with the storage-class specifier "static", 2747 // constitutes a tentative definition. Note: A tentative definition with 2748 // external linkage is valid (C99 6.2.2p5). 2749 if (IDecl->isTentativeDefinition(Context)) { 2750 QualType CheckType = T; 2751 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2752 2753 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2754 if (ArrayT) { 2755 CheckType = ArrayT->getElementType(); 2756 DiagID = diag::err_illegal_decl_array_incomplete_type; 2757 } 2758 2759 if (IDecl->isInvalidDecl()) { 2760 // Do nothing with invalid declarations 2761 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2762 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2763 // C99 6.9.2p3: If the declaration of an identifier for an object is 2764 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2765 // declared type shall not be an incomplete type. 2766 IDecl->setInvalidDecl(); 2767 } 2768 } 2769 } 2770 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2771 &Decls[0], Decls.size())); 2772} 2773 2774 2775/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2776/// to introduce parameters into function prototype scope. 2777Sema::DeclPtrTy 2778Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2779 const DeclSpec &DS = D.getDeclSpec(); 2780 2781 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2782 VarDecl::StorageClass StorageClass = VarDecl::None; 2783 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2784 StorageClass = VarDecl::Register; 2785 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2786 Diag(DS.getStorageClassSpecLoc(), 2787 diag::err_invalid_storage_class_in_func_decl); 2788 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2789 } 2790 2791 if (D.getDeclSpec().isThreadSpecified()) 2792 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2793 2794 DiagnoseFunctionSpecifiers(D); 2795 2796 // Check that there are no default arguments inside the type of this 2797 // parameter (C++ only). 2798 if (getLangOptions().CPlusPlus) 2799 CheckExtraCXXDefaultArguments(D); 2800 2801 // In this context, we *do not* check D.getInvalidType(). If the declarator 2802 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2803 // though it will not reflect the user specified type. 2804 QualType parmDeclType = GetTypeForDeclarator(D, S); 2805 if (parmDeclType.isNull()) { 2806 D.setInvalidType(true); 2807 parmDeclType = Context.IntTy; 2808 } 2809 2810 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2811 // Can this happen for params? We already checked that they don't conflict 2812 // among each other. Here they can only shadow globals, which is ok. 2813 IdentifierInfo *II = D.getIdentifier(); 2814 if (II) { 2815 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2816 if (PrevDecl->isTemplateParameter()) { 2817 // Maybe we will complain about the shadowed template parameter. 2818 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2819 // Just pretend that we didn't see the previous declaration. 2820 PrevDecl = 0; 2821 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2822 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2823 2824 // Recover by removing the name 2825 II = 0; 2826 D.SetIdentifier(0, D.getIdentifierLoc()); 2827 } 2828 } 2829 } 2830 2831 // Parameters can not be abstract class types. 2832 // For record types, this is done by the AbstractClassUsageDiagnoser once 2833 // the class has been completely parsed. 2834 if (!CurContext->isRecord() && 2835 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2836 diag::err_abstract_type_in_decl, 2837 AbstractParamType)) 2838 D.setInvalidType(true); 2839 2840 QualType T = adjustParameterType(parmDeclType); 2841 2842 ParmVarDecl *New; 2843 if (T == parmDeclType) // parameter type did not need adjustment 2844 New = ParmVarDecl::Create(Context, CurContext, 2845 D.getIdentifierLoc(), II, 2846 parmDeclType, StorageClass, 2847 0); 2848 else // keep track of both the adjusted and unadjusted types 2849 New = OriginalParmVarDecl::Create(Context, CurContext, 2850 D.getIdentifierLoc(), II, T, 2851 parmDeclType, StorageClass, 0); 2852 2853 if (D.getInvalidType()) 2854 New->setInvalidDecl(); 2855 2856 // Parameter declarators cannot be interface types. All ObjC objects are 2857 // passed by reference. 2858 if (T->isObjCInterfaceType()) { 2859 Diag(D.getIdentifierLoc(), 2860 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2861 New->setInvalidDecl(); 2862 } 2863 2864 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2865 if (D.getCXXScopeSpec().isSet()) { 2866 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2867 << D.getCXXScopeSpec().getRange(); 2868 New->setInvalidDecl(); 2869 } 2870 2871 // Add the parameter declaration into this scope. 2872 S->AddDecl(DeclPtrTy::make(New)); 2873 if (II) 2874 IdResolver.AddDecl(New); 2875 2876 ProcessDeclAttributes(New, D); 2877 return DeclPtrTy::make(New); 2878} 2879 2880void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2881 SourceLocation LocAfterDecls) { 2882 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2883 "Not a function declarator!"); 2884 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2885 2886 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2887 // for a K&R function. 2888 if (!FTI.hasPrototype) { 2889 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2890 --i; 2891 if (FTI.ArgInfo[i].Param == 0) { 2892 std::string Code = " int "; 2893 Code += FTI.ArgInfo[i].Ident->getName(); 2894 Code += ";\n"; 2895 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2896 << FTI.ArgInfo[i].Ident 2897 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2898 2899 // Implicitly declare the argument as type 'int' for lack of a better 2900 // type. 2901 DeclSpec DS; 2902 const char* PrevSpec; // unused 2903 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2904 PrevSpec); 2905 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2906 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2907 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2908 } 2909 } 2910 } 2911} 2912 2913Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2914 Declarator &D) { 2915 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2916 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2917 "Not a function declarator!"); 2918 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2919 2920 if (FTI.hasPrototype) { 2921 // FIXME: Diagnose arguments without names in C. 2922 } 2923 2924 Scope *ParentScope = FnBodyScope->getParent(); 2925 2926 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2927 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2928} 2929 2930Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2931 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2932 2933 CurFunctionNeedsScopeChecking = false; 2934 2935 // See if this is a redefinition. 2936 const FunctionDecl *Definition; 2937 if (FD->getBody(Context, Definition)) { 2938 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2939 Diag(Definition->getLocation(), diag::note_previous_definition); 2940 } 2941 2942 // Builtin functions cannot be defined. 2943 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2944 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2945 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2946 FD->setInvalidDecl(); 2947 } 2948 } 2949 2950 // The return type of a function definition must be complete 2951 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2952 QualType ResultType = FD->getResultType(); 2953 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2954 RequireCompleteType(FD->getLocation(), ResultType, 2955 diag::err_func_def_incomplete_result)) 2956 FD->setInvalidDecl(); 2957 2958 // GNU warning -Wmissing-prototypes: 2959 // Warn if a global function is defined without a previous 2960 // prototype declaration. This warning is issued even if the 2961 // definition itself provides a prototype. The aim is to detect 2962 // global functions that fail to be declared in header files. 2963 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2964 !FD->isMain()) { 2965 bool MissingPrototype = true; 2966 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2967 Prev; Prev = Prev->getPreviousDeclaration()) { 2968 // Ignore any declarations that occur in function or method 2969 // scope, because they aren't visible from the header. 2970 if (Prev->getDeclContext()->isFunctionOrMethod()) 2971 continue; 2972 2973 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2974 break; 2975 } 2976 2977 if (MissingPrototype) 2978 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2979 } 2980 2981 PushDeclContext(FnBodyScope, FD); 2982 2983 // Check the validity of our function parameters 2984 CheckParmsForFunctionDef(FD); 2985 2986 // Introduce our parameters into the function scope 2987 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2988 ParmVarDecl *Param = FD->getParamDecl(p); 2989 Param->setOwningFunction(FD); 2990 2991 // If this has an identifier, add it to the scope stack. 2992 if (Param->getIdentifier()) 2993 PushOnScopeChains(Param, FnBodyScope); 2994 } 2995 2996 // Checking attributes of current function definition 2997 // dllimport attribute. 2998 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2999 // dllimport attribute cannot be applied to definition. 3000 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3001 Diag(FD->getLocation(), 3002 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3003 << "dllimport"; 3004 FD->setInvalidDecl(); 3005 return DeclPtrTy::make(FD); 3006 } else { 3007 // If a symbol previously declared dllimport is later defined, the 3008 // attribute is ignored in subsequent references, and a warning is 3009 // emitted. 3010 Diag(FD->getLocation(), 3011 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3012 << FD->getNameAsCString() << "dllimport"; 3013 } 3014 } 3015 return DeclPtrTy::make(FD); 3016} 3017 3018 3019Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3020 Decl *dcl = D.getAs<Decl>(); 3021 CompoundStmt *Body =cast<CompoundStmt>(static_cast<Stmt*>(BodyArg.release())); 3022 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 3023 FD->setBody(Body); 3024 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3025 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3026 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3027 MD->setBody(Body); 3028 } else { 3029 Body->Destroy(Context); 3030 return DeclPtrTy(); 3031 } 3032 PopDeclContext(); 3033 // Verify and clean out per-function state. 3034 3035 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 3036 3037 // Check goto/label use. 3038 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3039 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 3040 LabelStmt *L = I->second; 3041 3042 // Verify that we have no forward references left. If so, there was a goto 3043 // or address of a label taken, but no definition of it. Label fwd 3044 // definitions are indicated with a null substmt. 3045 if (L->getSubStmt() != 0) 3046 continue; 3047 3048 // Emit error. 3049 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3050 3051 // At this point, we have gotos that use the bogus label. Stitch it into 3052 // the function body so that they aren't leaked and that the AST is well 3053 // formed. 3054 if (Body == 0) { 3055 // The whole function wasn't parsed correctly, just delete this. 3056 L->Destroy(Context); 3057 continue; 3058 } 3059 3060 // Otherwise, the body is valid: we want to stitch the label decl into the 3061 // function somewhere so that it is properly owned and so that the goto 3062 // has a valid target. Do this by creating a new compound stmt with the 3063 // label in it. 3064 3065 // Give the label a sub-statement. 3066 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3067 3068 std::vector<Stmt*> Elements(Body->body_begin(), Body->body_end()); 3069 Elements.push_back(L); 3070 Body->setStmts(Context, &Elements[0], Elements.size()); 3071 } 3072 FunctionLabelMap.clear(); 3073 3074 if (!Body) return D; 3075 3076 // Verify that that gotos and switch cases don't jump into scopes illegally. 3077 if (CurFunctionNeedsScopeChecking) 3078 DiagnoseInvalidJumps(Body); 3079 3080 return D; 3081} 3082 3083/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3084/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3085NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3086 IdentifierInfo &II, Scope *S) { 3087 // Before we produce a declaration for an implicitly defined 3088 // function, see whether there was a locally-scoped declaration of 3089 // this name as a function or variable. If so, use that 3090 // (non-visible) declaration, and complain about it. 3091 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3092 = LocallyScopedExternalDecls.find(&II); 3093 if (Pos != LocallyScopedExternalDecls.end()) { 3094 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3095 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3096 return Pos->second; 3097 } 3098 3099 // Extension in C99. Legal in C90, but warn about it. 3100 if (getLangOptions().C99) 3101 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3102 else 3103 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3104 3105 // FIXME: handle stuff like: 3106 // void foo() { extern float X(); } 3107 // void bar() { X(); } <-- implicit decl for X in another scope. 3108 3109 // Set a Declarator for the implicit definition: int foo(); 3110 const char *Dummy; 3111 DeclSpec DS; 3112 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3113 Error = Error; // Silence warning. 3114 assert(!Error && "Error setting up implicit decl!"); 3115 Declarator D(DS, Declarator::BlockContext); 3116 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3117 0, 0, 0, Loc, D), 3118 SourceLocation()); 3119 D.SetIdentifier(&II, Loc); 3120 3121 // Insert this function into translation-unit scope. 3122 3123 DeclContext *PrevDC = CurContext; 3124 CurContext = Context.getTranslationUnitDecl(); 3125 3126 FunctionDecl *FD = 3127 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3128 FD->setImplicit(); 3129 3130 CurContext = PrevDC; 3131 3132 AddKnownFunctionAttributes(FD); 3133 3134 return FD; 3135} 3136 3137/// \brief Adds any function attributes that we know a priori based on 3138/// the declaration of this function. 3139/// 3140/// These attributes can apply both to implicitly-declared builtins 3141/// (like __builtin___printf_chk) or to library-declared functions 3142/// like NSLog or printf. 3143void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3144 if (FD->isInvalidDecl()) 3145 return; 3146 3147 // If this is a built-in function, map its builtin attributes to 3148 // actual attributes. 3149 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3150 // Handle printf-formatting attributes. 3151 unsigned FormatIdx; 3152 bool HasVAListArg; 3153 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3154 if (!FD->getAttr<FormatAttr>()) 3155 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3156 FormatIdx + 2)); 3157 } 3158 3159 // Mark const if we don't care about errno and that is the only 3160 // thing preventing the function from being const. This allows 3161 // IRgen to use LLVM intrinsics for such functions. 3162 if (!getLangOptions().MathErrno && 3163 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3164 if (!FD->getAttr<ConstAttr>()) 3165 FD->addAttr(::new (Context) ConstAttr()); 3166 } 3167 } 3168 3169 IdentifierInfo *Name = FD->getIdentifier(); 3170 if (!Name) 3171 return; 3172 if ((!getLangOptions().CPlusPlus && 3173 FD->getDeclContext()->isTranslationUnit()) || 3174 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3175 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3176 LinkageSpecDecl::lang_c)) { 3177 // Okay: this could be a libc/libm/Objective-C function we know 3178 // about. 3179 } else 3180 return; 3181 3182 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3183 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3184 // FIXME: We known better than our headers. 3185 const_cast<FormatAttr *>(Format)->setType("printf"); 3186 } else 3187 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3188 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3189 if (!FD->getAttr<FormatAttr>()) 3190 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3191 } 3192} 3193 3194TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3195 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3196 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3197 3198 // Scope manipulation handled by caller. 3199 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3200 D.getIdentifierLoc(), 3201 D.getIdentifier(), 3202 T); 3203 3204 if (TagType *TT = dyn_cast<TagType>(T)) { 3205 TagDecl *TD = TT->getDecl(); 3206 3207 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3208 // keep track of the TypedefDecl. 3209 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3210 TD->setTypedefForAnonDecl(NewTD); 3211 } 3212 3213 if (D.getInvalidType()) 3214 NewTD->setInvalidDecl(); 3215 return NewTD; 3216} 3217 3218/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3219/// former case, Name will be non-null. In the later case, Name will be null. 3220/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3221/// reference/declaration/definition of a tag. 3222Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3223 SourceLocation KWLoc, const CXXScopeSpec &SS, 3224 IdentifierInfo *Name, SourceLocation NameLoc, 3225 AttributeList *Attr, AccessSpecifier AS) { 3226 // If this is not a definition, it must have a name. 3227 assert((Name != 0 || TK == TK_Definition) && 3228 "Nameless record must be a definition!"); 3229 3230 TagDecl::TagKind Kind; 3231 switch (TagSpec) { 3232 default: assert(0 && "Unknown tag type!"); 3233 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3234 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3235 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3236 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3237 } 3238 3239 DeclContext *SearchDC = CurContext; 3240 DeclContext *DC = CurContext; 3241 NamedDecl *PrevDecl = 0; 3242 3243 bool Invalid = false; 3244 3245 if (Name && SS.isNotEmpty()) { 3246 // We have a nested-name tag ('struct foo::bar'). 3247 3248 // Check for invalid 'foo::'. 3249 if (SS.isInvalid()) { 3250 Name = 0; 3251 goto CreateNewDecl; 3252 } 3253 3254 // FIXME: RequireCompleteDeclContext(SS)? 3255 DC = computeDeclContext(SS); 3256 SearchDC = DC; 3257 // Look-up name inside 'foo::'. 3258 PrevDecl = dyn_cast_or_null<TagDecl>( 3259 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3260 3261 // A tag 'foo::bar' must already exist. 3262 if (PrevDecl == 0) { 3263 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3264 Name = 0; 3265 goto CreateNewDecl; 3266 } 3267 } else if (Name) { 3268 // If this is a named struct, check to see if there was a previous forward 3269 // declaration or definition. 3270 // FIXME: We're looking into outer scopes here, even when we 3271 // shouldn't be. Doing so can result in ambiguities that we 3272 // shouldn't be diagnosing. 3273 LookupResult R = LookupName(S, Name, LookupTagName, 3274 /*RedeclarationOnly=*/(TK != TK_Reference)); 3275 if (R.isAmbiguous()) { 3276 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3277 // FIXME: This is not best way to recover from case like: 3278 // 3279 // struct S s; 3280 // 3281 // causes needless "incomplete type" error later. 3282 Name = 0; 3283 PrevDecl = 0; 3284 Invalid = true; 3285 } 3286 else 3287 PrevDecl = R; 3288 3289 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3290 // FIXME: This makes sure that we ignore the contexts associated 3291 // with C structs, unions, and enums when looking for a matching 3292 // tag declaration or definition. See the similar lookup tweak 3293 // in Sema::LookupName; is there a better way to deal with this? 3294 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3295 SearchDC = SearchDC->getParent(); 3296 } 3297 } 3298 3299 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3300 // Maybe we will complain about the shadowed template parameter. 3301 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3302 // Just pretend that we didn't see the previous declaration. 3303 PrevDecl = 0; 3304 } 3305 3306 if (PrevDecl) { 3307 // Check whether the previous declaration is usable. 3308 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3309 3310 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3311 // If this is a use of a previous tag, or if the tag is already declared 3312 // in the same scope (so that the definition/declaration completes or 3313 // rementions the tag), reuse the decl. 3314 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3315 // Make sure that this wasn't declared as an enum and now used as a 3316 // struct or something similar. 3317 if (PrevTagDecl->getTagKind() != Kind) { 3318 bool SafeToContinue 3319 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3320 Kind != TagDecl::TK_enum); 3321 if (SafeToContinue) 3322 Diag(KWLoc, diag::err_use_with_wrong_tag) 3323 << Name 3324 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3325 PrevTagDecl->getKindName()); 3326 else 3327 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3328 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3329 3330 if (SafeToContinue) 3331 Kind = PrevTagDecl->getTagKind(); 3332 else { 3333 // Recover by making this an anonymous redefinition. 3334 Name = 0; 3335 PrevDecl = 0; 3336 Invalid = true; 3337 } 3338 } 3339 3340 if (!Invalid) { 3341 // If this is a use, just return the declaration we found. 3342 3343 // FIXME: In the future, return a variant or some other clue 3344 // for the consumer of this Decl to know it doesn't own it. 3345 // For our current ASTs this shouldn't be a problem, but will 3346 // need to be changed with DeclGroups. 3347 if (TK == TK_Reference) 3348 return DeclPtrTy::make(PrevDecl); 3349 3350 // Diagnose attempts to redefine a tag. 3351 if (TK == TK_Definition) { 3352 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3353 Diag(NameLoc, diag::err_redefinition) << Name; 3354 Diag(Def->getLocation(), diag::note_previous_definition); 3355 // If this is a redefinition, recover by making this 3356 // struct be anonymous, which will make any later 3357 // references get the previous definition. 3358 Name = 0; 3359 PrevDecl = 0; 3360 Invalid = true; 3361 } else { 3362 // If the type is currently being defined, complain 3363 // about a nested redefinition. 3364 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3365 if (Tag->isBeingDefined()) { 3366 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3367 Diag(PrevTagDecl->getLocation(), 3368 diag::note_previous_definition); 3369 Name = 0; 3370 PrevDecl = 0; 3371 Invalid = true; 3372 } 3373 } 3374 3375 // Okay, this is definition of a previously declared or referenced 3376 // tag PrevDecl. We're going to create a new Decl for it. 3377 } 3378 } 3379 // If we get here we have (another) forward declaration or we 3380 // have a definition. Just create a new decl. 3381 } else { 3382 // If we get here, this is a definition of a new tag type in a nested 3383 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3384 // new decl/type. We set PrevDecl to NULL so that the entities 3385 // have distinct types. 3386 PrevDecl = 0; 3387 } 3388 // If we get here, we're going to create a new Decl. If PrevDecl 3389 // is non-NULL, it's a definition of the tag declared by 3390 // PrevDecl. If it's NULL, we have a new definition. 3391 } else { 3392 // PrevDecl is a namespace, template, or anything else 3393 // that lives in the IDNS_Tag identifier namespace. 3394 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3395 // The tag name clashes with a namespace name, issue an error and 3396 // recover by making this tag be anonymous. 3397 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3398 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3399 Name = 0; 3400 PrevDecl = 0; 3401 Invalid = true; 3402 } else { 3403 // The existing declaration isn't relevant to us; we're in a 3404 // new scope, so clear out the previous declaration. 3405 PrevDecl = 0; 3406 } 3407 } 3408 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3409 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3410 // C.scope.pdecl]p5: 3411 // -- for an elaborated-type-specifier of the form 3412 // 3413 // class-key identifier 3414 // 3415 // if the elaborated-type-specifier is used in the 3416 // decl-specifier-seq or parameter-declaration-clause of a 3417 // function defined in namespace scope, the identifier is 3418 // declared as a class-name in the namespace that contains 3419 // the declaration; otherwise, except as a friend 3420 // declaration, the identifier is declared in the smallest 3421 // non-class, non-function-prototype scope that contains the 3422 // declaration. 3423 // 3424 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3425 // C structs and unions. 3426 // 3427 // GNU C also supports this behavior as part of its incomplete 3428 // enum types extension, while GNU C++ does not. 3429 // 3430 // Find the context where we'll be declaring the tag. 3431 // FIXME: We would like to maintain the current DeclContext as the 3432 // lexical context, 3433 while (SearchDC->isRecord()) 3434 SearchDC = SearchDC->getParent(); 3435 3436 // Find the scope where we'll be declaring the tag. 3437 while (S->isClassScope() || 3438 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3439 ((S->getFlags() & Scope::DeclScope) == 0) || 3440 (S->getEntity() && 3441 ((DeclContext *)S->getEntity())->isTransparentContext())) 3442 S = S->getParent(); 3443 } 3444 3445CreateNewDecl: 3446 3447 // If there is an identifier, use the location of the identifier as the 3448 // location of the decl, otherwise use the location of the struct/union 3449 // keyword. 3450 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3451 3452 // Otherwise, create a new declaration. If there is a previous 3453 // declaration of the same entity, the two will be linked via 3454 // PrevDecl. 3455 TagDecl *New; 3456 3457 if (Kind == TagDecl::TK_enum) { 3458 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3459 // enum X { A, B, C } D; D should chain to X. 3460 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3461 cast_or_null<EnumDecl>(PrevDecl)); 3462 // If this is an undefined enum, warn. 3463 if (TK != TK_Definition && !Invalid) { 3464 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3465 : diag::ext_forward_ref_enum; 3466 Diag(Loc, DK); 3467 } 3468 } else { 3469 // struct/union/class 3470 3471 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3472 // struct X { int A; } D; D should chain to X. 3473 if (getLangOptions().CPlusPlus) 3474 // FIXME: Look for a way to use RecordDecl for simple structs. 3475 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3476 cast_or_null<CXXRecordDecl>(PrevDecl)); 3477 else 3478 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3479 cast_or_null<RecordDecl>(PrevDecl)); 3480 } 3481 3482 if (Kind != TagDecl::TK_enum) { 3483 // Handle #pragma pack: if the #pragma pack stack has non-default 3484 // alignment, make up a packed attribute for this decl. These 3485 // attributes are checked when the ASTContext lays out the 3486 // structure. 3487 // 3488 // It is important for implementing the correct semantics that this 3489 // happen here (in act on tag decl). The #pragma pack stack is 3490 // maintained as a result of parser callbacks which can occur at 3491 // many points during the parsing of a struct declaration (because 3492 // the #pragma tokens are effectively skipped over during the 3493 // parsing of the struct). 3494 if (unsigned Alignment = getPragmaPackAlignment()) 3495 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3496 } 3497 3498 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3499 // C++ [dcl.typedef]p3: 3500 // [...] Similarly, in a given scope, a class or enumeration 3501 // shall not be declared with the same name as a typedef-name 3502 // that is declared in that scope and refers to a type other 3503 // than the class or enumeration itself. 3504 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3505 TypedefDecl *PrevTypedef = 0; 3506 if (Lookup.getKind() == LookupResult::Found) 3507 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3508 3509 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3510 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3511 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3512 Diag(Loc, diag::err_tag_definition_of_typedef) 3513 << Context.getTypeDeclType(New) 3514 << PrevTypedef->getUnderlyingType(); 3515 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3516 Invalid = true; 3517 } 3518 } 3519 3520 if (Invalid) 3521 New->setInvalidDecl(); 3522 3523 if (Attr) 3524 ProcessDeclAttributeList(New, Attr); 3525 3526 // If we're declaring or defining a tag in function prototype scope 3527 // in C, note that this type can only be used within the function. 3528 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3529 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3530 3531 // Set the lexical context. If the tag has a C++ scope specifier, the 3532 // lexical context will be different from the semantic context. 3533 New->setLexicalDeclContext(CurContext); 3534 3535 // Set the access specifier. 3536 SetMemberAccessSpecifier(New, PrevDecl, AS); 3537 3538 if (TK == TK_Definition) 3539 New->startDefinition(); 3540 3541 // If this has an identifier, add it to the scope stack. 3542 if (Name) { 3543 S = getNonFieldDeclScope(S); 3544 PushOnScopeChains(New, S); 3545 } else { 3546 CurContext->addDecl(Context, New); 3547 } 3548 3549 return DeclPtrTy::make(New); 3550} 3551 3552void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3553 AdjustDeclIfTemplate(TagD); 3554 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3555 3556 // Enter the tag context. 3557 PushDeclContext(S, Tag); 3558 3559 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3560 FieldCollector->StartClass(); 3561 3562 if (Record->getIdentifier()) { 3563 // C++ [class]p2: 3564 // [...] The class-name is also inserted into the scope of the 3565 // class itself; this is known as the injected-class-name. For 3566 // purposes of access checking, the injected-class-name is treated 3567 // as if it were a public member name. 3568 CXXRecordDecl *InjectedClassName 3569 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3570 CurContext, Record->getLocation(), 3571 Record->getIdentifier(), Record); 3572 InjectedClassName->setImplicit(); 3573 InjectedClassName->setAccess(AS_public); 3574 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3575 InjectedClassName->setDescribedClassTemplate(Template); 3576 PushOnScopeChains(InjectedClassName, S); 3577 assert(InjectedClassName->isInjectedClassName() && 3578 "Broken injected-class-name"); 3579 } 3580 } 3581} 3582 3583void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3584 AdjustDeclIfTemplate(TagD); 3585 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3586 3587 if (isa<CXXRecordDecl>(Tag)) 3588 FieldCollector->FinishClass(); 3589 3590 // Exit this scope of this tag's definition. 3591 PopDeclContext(); 3592 3593 // Notify the consumer that we've defined a tag. 3594 Consumer.HandleTagDeclDefinition(Tag); 3595} 3596 3597// Note that FieldName may be null for anonymous bitfields. 3598bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3599 QualType FieldTy, const Expr *BitWidth) { 3600 3601 // C99 6.7.2.1p4 - verify the field type. 3602 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3603 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3604 // Handle incomplete types with specific error. 3605 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3606 return true; 3607 if (FieldName) 3608 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3609 << FieldName << FieldTy << BitWidth->getSourceRange(); 3610 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3611 << FieldTy << BitWidth->getSourceRange(); 3612 } 3613 3614 // If the bit-width is type- or value-dependent, don't try to check 3615 // it now. 3616 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3617 return false; 3618 3619 llvm::APSInt Value; 3620 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3621 return true; 3622 3623 // Zero-width bitfield is ok for anonymous field. 3624 if (Value == 0 && FieldName) 3625 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3626 3627 if (Value.isSigned() && Value.isNegative()) { 3628 if (FieldName) 3629 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3630 << FieldName << Value.toString(10); 3631 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3632 << Value.toString(10); 3633 } 3634 3635 if (!FieldTy->isDependentType()) { 3636 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3637 if (Value.getZExtValue() > TypeSize) { 3638 if (FieldName) 3639 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3640 << FieldName << (unsigned)TypeSize; 3641 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3642 << (unsigned)TypeSize; 3643 } 3644 } 3645 3646 return false; 3647} 3648 3649/// ActOnField - Each field of a struct/union/class is passed into this in order 3650/// to create a FieldDecl object for it. 3651Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3652 SourceLocation DeclStart, 3653 Declarator &D, ExprTy *BitfieldWidth) { 3654 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3655 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3656 AS_public); 3657 return DeclPtrTy::make(Res); 3658} 3659 3660/// HandleField - Analyze a field of a C struct or a C++ data member. 3661/// 3662FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3663 SourceLocation DeclStart, 3664 Declarator &D, Expr *BitWidth, 3665 AccessSpecifier AS) { 3666 IdentifierInfo *II = D.getIdentifier(); 3667 SourceLocation Loc = DeclStart; 3668 if (II) Loc = D.getIdentifierLoc(); 3669 3670 QualType T = GetTypeForDeclarator(D, S); 3671 if (getLangOptions().CPlusPlus) 3672 CheckExtraCXXDefaultArguments(D); 3673 3674 DiagnoseFunctionSpecifiers(D); 3675 3676 if (D.getDeclSpec().isThreadSpecified()) 3677 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3678 3679 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3680 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3681 PrevDecl = 0; 3682 3683 FieldDecl *NewFD 3684 = CheckFieldDecl(II, T, Record, Loc, 3685 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3686 BitWidth, AS, PrevDecl, &D); 3687 if (NewFD->isInvalidDecl() && PrevDecl) { 3688 // Don't introduce NewFD into scope; there's already something 3689 // with the same name in the same scope. 3690 } else if (II) { 3691 PushOnScopeChains(NewFD, S); 3692 } else 3693 Record->addDecl(Context, NewFD); 3694 3695 return NewFD; 3696} 3697 3698/// \brief Build a new FieldDecl and check its well-formedness. 3699/// 3700/// This routine builds a new FieldDecl given the fields name, type, 3701/// record, etc. \p PrevDecl should refer to any previous declaration 3702/// with the same name and in the same scope as the field to be 3703/// created. 3704/// 3705/// \returns a new FieldDecl. 3706/// 3707/// \todo The Declarator argument is a hack. It will be removed once 3708FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3709 RecordDecl *Record, SourceLocation Loc, 3710 bool Mutable, Expr *BitWidth, 3711 AccessSpecifier AS, NamedDecl *PrevDecl, 3712 Declarator *D) { 3713 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3714 bool InvalidDecl = false; 3715 3716 // If we receive a broken type, recover by assuming 'int' and 3717 // marking this declaration as invalid. 3718 if (T.isNull()) { 3719 InvalidDecl = true; 3720 T = Context.IntTy; 3721 } 3722 3723 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3724 // than a variably modified type. 3725 if (T->isVariablyModifiedType()) { 3726 bool SizeIsNegative; 3727 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3728 SizeIsNegative); 3729 if (!FixedTy.isNull()) { 3730 Diag(Loc, diag::warn_illegal_constant_array_size); 3731 T = FixedTy; 3732 } else { 3733 if (SizeIsNegative) 3734 Diag(Loc, diag::err_typecheck_negative_array_size); 3735 else 3736 Diag(Loc, diag::err_typecheck_field_variable_size); 3737 T = Context.IntTy; 3738 InvalidDecl = true; 3739 } 3740 } 3741 3742 // Fields can not have abstract class types 3743 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3744 AbstractFieldType)) 3745 InvalidDecl = true; 3746 3747 // If this is declared as a bit-field, check the bit-field. 3748 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3749 InvalidDecl = true; 3750 DeleteExpr(BitWidth); 3751 BitWidth = 0; 3752 } 3753 3754 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3755 Mutable); 3756 3757 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3758 Diag(Loc, diag::err_duplicate_member) << II; 3759 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3760 NewFD->setInvalidDecl(); 3761 Record->setInvalidDecl(); 3762 } 3763 3764 if (getLangOptions().CPlusPlus && !T->isPODType()) 3765 cast<CXXRecordDecl>(Record)->setPOD(false); 3766 3767 // FIXME: We need to pass in the attributes given an AST 3768 // representation, not a parser representation. 3769 if (D) 3770 ProcessDeclAttributes(NewFD, *D); 3771 3772 if (T.isObjCGCWeak()) 3773 Diag(Loc, diag::warn_attribute_weak_on_field); 3774 3775 if (InvalidDecl) 3776 NewFD->setInvalidDecl(); 3777 3778 NewFD->setAccess(AS); 3779 3780 // C++ [dcl.init.aggr]p1: 3781 // An aggregate is an array or a class (clause 9) with [...] no 3782 // private or protected non-static data members (clause 11). 3783 // A POD must be an aggregate. 3784 if (getLangOptions().CPlusPlus && 3785 (AS == AS_private || AS == AS_protected)) { 3786 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3787 CXXRecord->setAggregate(false); 3788 CXXRecord->setPOD(false); 3789 } 3790 3791 return NewFD; 3792} 3793 3794/// TranslateIvarVisibility - Translate visibility from a token ID to an 3795/// AST enum value. 3796static ObjCIvarDecl::AccessControl 3797TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3798 switch (ivarVisibility) { 3799 default: assert(0 && "Unknown visitibility kind"); 3800 case tok::objc_private: return ObjCIvarDecl::Private; 3801 case tok::objc_public: return ObjCIvarDecl::Public; 3802 case tok::objc_protected: return ObjCIvarDecl::Protected; 3803 case tok::objc_package: return ObjCIvarDecl::Package; 3804 } 3805} 3806 3807/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3808/// in order to create an IvarDecl object for it. 3809Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3810 SourceLocation DeclStart, 3811 Declarator &D, ExprTy *BitfieldWidth, 3812 tok::ObjCKeywordKind Visibility) { 3813 3814 IdentifierInfo *II = D.getIdentifier(); 3815 Expr *BitWidth = (Expr*)BitfieldWidth; 3816 SourceLocation Loc = DeclStart; 3817 if (II) Loc = D.getIdentifierLoc(); 3818 3819 // FIXME: Unnamed fields can be handled in various different ways, for 3820 // example, unnamed unions inject all members into the struct namespace! 3821 3822 QualType T = GetTypeForDeclarator(D, S); 3823 bool InvalidDecl = false; 3824 if (T.isNull()) { 3825 InvalidDecl = true; 3826 T = Context.IntTy; 3827 } 3828 3829 if (BitWidth) { 3830 // 6.7.2.1p3, 6.7.2.1p4 3831 if (VerifyBitField(Loc, II, T, BitWidth)) { 3832 InvalidDecl = true; 3833 DeleteExpr(BitWidth); 3834 BitWidth = 0; 3835 } 3836 } else { 3837 // Not a bitfield. 3838 3839 // validate II. 3840 3841 } 3842 3843 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3844 // than a variably modified type. 3845 if (T->isVariablyModifiedType()) { 3846 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3847 InvalidDecl = true; 3848 } 3849 3850 // Get the visibility (access control) for this ivar. 3851 ObjCIvarDecl::AccessControl ac = 3852 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3853 : ObjCIvarDecl::None; 3854 3855 // Construct the decl. 3856 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3857 (Expr *)BitfieldWidth); 3858 3859 if (II) { 3860 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3861 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3862 && !isa<TagDecl>(PrevDecl)) { 3863 Diag(Loc, diag::err_duplicate_member) << II; 3864 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3865 NewID->setInvalidDecl(); 3866 } 3867 } 3868 3869 // Process attributes attached to the ivar. 3870 ProcessDeclAttributes(NewID, D); 3871 3872 if (D.getInvalidType() || InvalidDecl) 3873 NewID->setInvalidDecl(); 3874 3875 if (II) { 3876 // FIXME: When interfaces are DeclContexts, we'll need to add 3877 // these to the interface. 3878 S->AddDecl(DeclPtrTy::make(NewID)); 3879 IdResolver.AddDecl(NewID); 3880 } 3881 3882 return DeclPtrTy::make(NewID); 3883} 3884 3885void Sema::ActOnFields(Scope* S, 3886 SourceLocation RecLoc, DeclPtrTy RecDecl, 3887 DeclPtrTy *Fields, unsigned NumFields, 3888 SourceLocation LBrac, SourceLocation RBrac, 3889 AttributeList *Attr) { 3890 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3891 assert(EnclosingDecl && "missing record or interface decl"); 3892 3893 // If the decl this is being inserted into is invalid, then it may be a 3894 // redeclaration or some other bogus case. Don't try to add fields to it. 3895 if (EnclosingDecl->isInvalidDecl()) { 3896 // FIXME: Deallocate fields? 3897 return; 3898 } 3899 3900 3901 // Verify that all the fields are okay. 3902 unsigned NumNamedMembers = 0; 3903 llvm::SmallVector<FieldDecl*, 32> RecFields; 3904 3905 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3906 for (unsigned i = 0; i != NumFields; ++i) { 3907 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3908 3909 // Get the type for the field. 3910 Type *FDTy = FD->getType().getTypePtr(); 3911 3912 if (!FD->isAnonymousStructOrUnion()) { 3913 // Remember all fields written by the user. 3914 RecFields.push_back(FD); 3915 } 3916 3917 // If the field is already invalid for some reason, don't emit more 3918 // diagnostics about it. 3919 if (FD->isInvalidDecl()) 3920 continue; 3921 3922 // C99 6.7.2.1p2: 3923 // A structure or union shall not contain a member with 3924 // incomplete or function type (hence, a structure shall not 3925 // contain an instance of itself, but may contain a pointer to 3926 // an instance of itself), except that the last member of a 3927 // structure with more than one named member may have incomplete 3928 // array type; such a structure (and any union containing, 3929 // possibly recursively, a member that is such a structure) 3930 // shall not be a member of a structure or an element of an 3931 // array. 3932 if (FDTy->isFunctionType()) { 3933 // Field declared as a function. 3934 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3935 << FD->getDeclName(); 3936 FD->setInvalidDecl(); 3937 EnclosingDecl->setInvalidDecl(); 3938 continue; 3939 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3940 Record && Record->isStruct()) { 3941 // Flexible array member. 3942 if (NumNamedMembers < 1) { 3943 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3944 << FD->getDeclName(); 3945 FD->setInvalidDecl(); 3946 EnclosingDecl->setInvalidDecl(); 3947 continue; 3948 } 3949 // Okay, we have a legal flexible array member at the end of the struct. 3950 if (Record) 3951 Record->setHasFlexibleArrayMember(true); 3952 } else if (!FDTy->isDependentType() && 3953 RequireCompleteType(FD->getLocation(), FD->getType(), 3954 diag::err_field_incomplete)) { 3955 // Incomplete type 3956 FD->setInvalidDecl(); 3957 EnclosingDecl->setInvalidDecl(); 3958 continue; 3959 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3960 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3961 // If this is a member of a union, then entire union becomes "flexible". 3962 if (Record && Record->isUnion()) { 3963 Record->setHasFlexibleArrayMember(true); 3964 } else { 3965 // If this is a struct/class and this is not the last element, reject 3966 // it. Note that GCC supports variable sized arrays in the middle of 3967 // structures. 3968 if (i != NumFields-1) 3969 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3970 << FD->getDeclName(); 3971 else { 3972 // We support flexible arrays at the end of structs in 3973 // other structs as an extension. 3974 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3975 << FD->getDeclName(); 3976 if (Record) 3977 Record->setHasFlexibleArrayMember(true); 3978 } 3979 } 3980 } 3981 } else if (FDTy->isObjCInterfaceType()) { 3982 /// A field cannot be an Objective-c object 3983 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3984 FD->setInvalidDecl(); 3985 EnclosingDecl->setInvalidDecl(); 3986 continue; 3987 } 3988 // Keep track of the number of named members. 3989 if (FD->getIdentifier()) 3990 ++NumNamedMembers; 3991 } 3992 3993 // Okay, we successfully defined 'Record'. 3994 if (Record) { 3995 Record->completeDefinition(Context); 3996 } else { 3997 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3998 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3999 ID->setIVarList(ClsFields, RecFields.size(), Context); 4000 ID->setLocEnd(RBrac); 4001 4002 // Must enforce the rule that ivars in the base classes may not be 4003 // duplicates. 4004 if (ID->getSuperClass()) { 4005 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 4006 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 4007 ObjCIvarDecl* Ivar = (*IVI); 4008 IdentifierInfo *II = Ivar->getIdentifier(); 4009 ObjCIvarDecl* prevIvar = 4010 ID->getSuperClass()->lookupInstanceVariable(Context, II); 4011 if (prevIvar) { 4012 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 4013 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 4014 } 4015 } 4016 } 4017 } else if (ObjCImplementationDecl *IMPDecl = 4018 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 4019 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 4020 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) { 4021 // FIXME: Set the DeclContext correctly when we build the 4022 // declarations. 4023 ClsFields[I]->setLexicalDeclContext(IMPDecl); 4024 IMPDecl->addDecl(Context, ClsFields[I]); 4025 } 4026 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 4027 } 4028 } 4029 4030 if (Attr) 4031 ProcessDeclAttributeList(Record, Attr); 4032} 4033 4034EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 4035 EnumConstantDecl *LastEnumConst, 4036 SourceLocation IdLoc, 4037 IdentifierInfo *Id, 4038 ExprArg val) { 4039 Expr *Val = (Expr *)val.get(); 4040 4041 llvm::APSInt EnumVal(32); 4042 QualType EltTy; 4043 if (Val && !Val->isTypeDependent()) { 4044 // Make sure to promote the operand type to int. 4045 UsualUnaryConversions(Val); 4046 if (Val != val.get()) { 4047 val.release(); 4048 val = Val; 4049 } 4050 4051 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4052 SourceLocation ExpLoc; 4053 if (!Val->isValueDependent() && 4054 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4055 Val = 0; 4056 } else { 4057 EltTy = Val->getType(); 4058 } 4059 } 4060 4061 if (!Val) { 4062 if (LastEnumConst) { 4063 // Assign the last value + 1. 4064 EnumVal = LastEnumConst->getInitVal(); 4065 ++EnumVal; 4066 4067 // Check for overflow on increment. 4068 if (EnumVal < LastEnumConst->getInitVal()) 4069 Diag(IdLoc, diag::warn_enum_value_overflow); 4070 4071 EltTy = LastEnumConst->getType(); 4072 } else { 4073 // First value, set to zero. 4074 EltTy = Context.IntTy; 4075 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4076 } 4077 } 4078 4079 val.release(); 4080 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4081 Val, EnumVal); 4082} 4083 4084 4085Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4086 DeclPtrTy lastEnumConst, 4087 SourceLocation IdLoc, 4088 IdentifierInfo *Id, 4089 SourceLocation EqualLoc, ExprTy *val) { 4090 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4091 EnumConstantDecl *LastEnumConst = 4092 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4093 Expr *Val = static_cast<Expr*>(val); 4094 4095 // The scope passed in may not be a decl scope. Zip up the scope tree until 4096 // we find one that is. 4097 S = getNonFieldDeclScope(S); 4098 4099 // Verify that there isn't already something declared with this name in this 4100 // scope. 4101 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4102 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4103 // Maybe we will complain about the shadowed template parameter. 4104 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4105 // Just pretend that we didn't see the previous declaration. 4106 PrevDecl = 0; 4107 } 4108 4109 if (PrevDecl) { 4110 // When in C++, we may get a TagDecl with the same name; in this case the 4111 // enum constant will 'hide' the tag. 4112 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4113 "Received TagDecl when not in C++!"); 4114 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4115 if (isa<EnumConstantDecl>(PrevDecl)) 4116 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4117 else 4118 Diag(IdLoc, diag::err_redefinition) << Id; 4119 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4120 if (Val) Val->Destroy(Context); 4121 return DeclPtrTy(); 4122 } 4123 } 4124 4125 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4126 IdLoc, Id, Owned(Val)); 4127 4128 // Register this decl in the current scope stack. 4129 if (New) 4130 PushOnScopeChains(New, S); 4131 4132 return DeclPtrTy::make(New); 4133} 4134 4135// FIXME: For consistency with ActOnFields(), we should have the parser 4136// pass in the source location for the left/right braces. 4137void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4138 DeclPtrTy *Elements, unsigned NumElements) { 4139 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4140 QualType EnumType = Context.getTypeDeclType(Enum); 4141 4142 // TODO: If the result value doesn't fit in an int, it must be a long or long 4143 // long value. ISO C does not support this, but GCC does as an extension, 4144 // emit a warning. 4145 unsigned IntWidth = Context.Target.getIntWidth(); 4146 4147 // Verify that all the values are okay, compute the size of the values, and 4148 // reverse the list. 4149 unsigned NumNegativeBits = 0; 4150 unsigned NumPositiveBits = 0; 4151 4152 // Keep track of whether all elements have type int. 4153 bool AllElementsInt = true; 4154 4155 for (unsigned i = 0; i != NumElements; ++i) { 4156 EnumConstantDecl *ECD = 4157 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4158 if (!ECD) continue; // Already issued a diagnostic. 4159 4160 // If the enum value doesn't fit in an int, emit an extension warning. 4161 const llvm::APSInt &InitVal = ECD->getInitVal(); 4162 assert(InitVal.getBitWidth() >= IntWidth && 4163 "Should have promoted value to int"); 4164 if (InitVal.getBitWidth() > IntWidth) { 4165 llvm::APSInt V(InitVal); 4166 V.trunc(IntWidth); 4167 V.extend(InitVal.getBitWidth()); 4168 if (V != InitVal) 4169 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4170 << InitVal.toString(10); 4171 } 4172 4173 // Keep track of the size of positive and negative values. 4174 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4175 NumPositiveBits = std::max(NumPositiveBits, 4176 (unsigned)InitVal.getActiveBits()); 4177 else 4178 NumNegativeBits = std::max(NumNegativeBits, 4179 (unsigned)InitVal.getMinSignedBits()); 4180 4181 // Keep track of whether every enum element has type int (very commmon). 4182 if (AllElementsInt) 4183 AllElementsInt = ECD->getType() == Context.IntTy; 4184 } 4185 4186 // Figure out the type that should be used for this enum. 4187 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4188 QualType BestType; 4189 unsigned BestWidth; 4190 4191 if (NumNegativeBits) { 4192 // If there is a negative value, figure out the smallest integer type (of 4193 // int/long/longlong) that fits. 4194 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4195 BestType = Context.IntTy; 4196 BestWidth = IntWidth; 4197 } else { 4198 BestWidth = Context.Target.getLongWidth(); 4199 4200 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4201 BestType = Context.LongTy; 4202 else { 4203 BestWidth = Context.Target.getLongLongWidth(); 4204 4205 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4206 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4207 BestType = Context.LongLongTy; 4208 } 4209 } 4210 } else { 4211 // If there is no negative value, figure out which of uint, ulong, ulonglong 4212 // fits. 4213 if (NumPositiveBits <= IntWidth) { 4214 BestType = Context.UnsignedIntTy; 4215 BestWidth = IntWidth; 4216 } else if (NumPositiveBits <= 4217 (BestWidth = Context.Target.getLongWidth())) { 4218 BestType = Context.UnsignedLongTy; 4219 } else { 4220 BestWidth = Context.Target.getLongLongWidth(); 4221 assert(NumPositiveBits <= BestWidth && 4222 "How could an initializer get larger than ULL?"); 4223 BestType = Context.UnsignedLongLongTy; 4224 } 4225 } 4226 4227 // Loop over all of the enumerator constants, changing their types to match 4228 // the type of the enum if needed. 4229 for (unsigned i = 0; i != NumElements; ++i) { 4230 EnumConstantDecl *ECD = 4231 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4232 if (!ECD) continue; // Already issued a diagnostic. 4233 4234 // Standard C says the enumerators have int type, but we allow, as an 4235 // extension, the enumerators to be larger than int size. If each 4236 // enumerator value fits in an int, type it as an int, otherwise type it the 4237 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4238 // that X has type 'int', not 'unsigned'. 4239 if (ECD->getType() == Context.IntTy) { 4240 // Make sure the init value is signed. 4241 llvm::APSInt IV = ECD->getInitVal(); 4242 IV.setIsSigned(true); 4243 ECD->setInitVal(IV); 4244 4245 if (getLangOptions().CPlusPlus) 4246 // C++ [dcl.enum]p4: Following the closing brace of an 4247 // enum-specifier, each enumerator has the type of its 4248 // enumeration. 4249 ECD->setType(EnumType); 4250 continue; // Already int type. 4251 } 4252 4253 // Determine whether the value fits into an int. 4254 llvm::APSInt InitVal = ECD->getInitVal(); 4255 bool FitsInInt; 4256 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4257 FitsInInt = InitVal.getActiveBits() < IntWidth; 4258 else 4259 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4260 4261 // If it fits into an integer type, force it. Otherwise force it to match 4262 // the enum decl type. 4263 QualType NewTy; 4264 unsigned NewWidth; 4265 bool NewSign; 4266 if (FitsInInt) { 4267 NewTy = Context.IntTy; 4268 NewWidth = IntWidth; 4269 NewSign = true; 4270 } else if (ECD->getType() == BestType) { 4271 // Already the right type! 4272 if (getLangOptions().CPlusPlus) 4273 // C++ [dcl.enum]p4: Following the closing brace of an 4274 // enum-specifier, each enumerator has the type of its 4275 // enumeration. 4276 ECD->setType(EnumType); 4277 continue; 4278 } else { 4279 NewTy = BestType; 4280 NewWidth = BestWidth; 4281 NewSign = BestType->isSignedIntegerType(); 4282 } 4283 4284 // Adjust the APSInt value. 4285 InitVal.extOrTrunc(NewWidth); 4286 InitVal.setIsSigned(NewSign); 4287 ECD->setInitVal(InitVal); 4288 4289 // Adjust the Expr initializer and type. 4290 if (ECD->getInitExpr()) 4291 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4292 /*isLvalue=*/false)); 4293 if (getLangOptions().CPlusPlus) 4294 // C++ [dcl.enum]p4: Following the closing brace of an 4295 // enum-specifier, each enumerator has the type of its 4296 // enumeration. 4297 ECD->setType(EnumType); 4298 else 4299 ECD->setType(NewTy); 4300 } 4301 4302 Enum->completeDefinition(Context, BestType); 4303} 4304 4305Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4306 ExprArg expr) { 4307 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4308 4309 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4310 Loc, AsmString)); 4311} 4312 4313