SemaDecl.cpp revision 9f9bf258f8ebae30bfb70feb9d797d6eb67b0460
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/AST/StmtCXX.h" 22#include "clang/Parse/DeclSpec.h" 23#include "clang/Basic/TargetInfo.h" 24#include "clang/Basic/SourceManager.h" 25// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 26#include "clang/Lex/Preprocessor.h" 27#include "clang/Lex/HeaderSearch.h" 28#include "llvm/ADT/SmallSet.h" 29#include "llvm/ADT/STLExtras.h" 30#include <algorithm> 31#include <functional> 32using namespace clang; 33 34/// getDeclName - Return a pretty name for the specified decl if possible, or 35/// an empty string if not. This is used for pretty crash reporting. 36std::string Sema::getDeclName(DeclPtrTy d) { 37 Decl *D = d.getAs<Decl>(); 38 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 39 return DN->getQualifiedNameAsString(); 40 return ""; 41} 42 43Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 44 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 45} 46 47/// \brief If the identifier refers to a type name within this scope, 48/// return the declaration of that type. 49/// 50/// This routine performs ordinary name lookup of the identifier II 51/// within the given scope, with optional C++ scope specifier SS, to 52/// determine whether the name refers to a type. If so, returns an 53/// opaque pointer (actually a QualType) corresponding to that 54/// type. Otherwise, returns NULL. 55/// 56/// If name lookup results in an ambiguity, this routine will complain 57/// and then return NULL. 58Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 59 Scope *S, const CXXScopeSpec *SS) { 60 // C++ [temp.res]p3: 61 // A qualified-id that refers to a type and in which the 62 // nested-name-specifier depends on a template-parameter (14.6.2) 63 // shall be prefixed by the keyword typename to indicate that the 64 // qualified-id denotes a type, forming an 65 // elaborated-type-specifier (7.1.5.3). 66 // 67 // We therefore do not perform any name lookup up SS is a dependent 68 // scope name. FIXME: we will need to perform a special kind of 69 // lookup if the scope specifier names a member of the current 70 // instantiation. 71 if (SS && isDependentScopeSpecifier(*SS)) 72 return 0; 73 74 NamedDecl *IIDecl = 0; 75 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 76 false, false); 77 switch (Result.getKind()) { 78 case LookupResult::NotFound: 79 case LookupResult::FoundOverloaded: 80 return 0; 81 82 case LookupResult::AmbiguousBaseSubobjectTypes: 83 case LookupResult::AmbiguousBaseSubobjects: 84 case LookupResult::AmbiguousReference: { 85 // Look to see if we have a type anywhere in the list of results. 86 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 87 Res != ResEnd; ++Res) { 88 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 89 if (!IIDecl || 90 (*Res)->getLocation().getRawEncoding() < 91 IIDecl->getLocation().getRawEncoding()) 92 IIDecl = *Res; 93 } 94 } 95 96 if (!IIDecl) { 97 // None of the entities we found is a type, so there is no way 98 // to even assume that the result is a type. In this case, don't 99 // complain about the ambiguity. The parser will either try to 100 // perform this lookup again (e.g., as an object name), which 101 // will produce the ambiguity, or will complain that it expected 102 // a type name. 103 Result.Destroy(); 104 return 0; 105 } 106 107 // We found a type within the ambiguous lookup; diagnose the 108 // ambiguity and then return that type. This might be the right 109 // answer, or it might not be, but it suppresses any attempt to 110 // perform the name lookup again. 111 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 112 break; 113 } 114 115 case LookupResult::Found: 116 IIDecl = Result.getAsDecl(); 117 break; 118 } 119 120 if (IIDecl) { 121 QualType T; 122 123 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 124 // Check whether we can use this type 125 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 126 127 T = Context.getTypeDeclType(TD); 128 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 129 // Check whether we can use this interface. 130 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 131 132 T = Context.getObjCInterfaceType(IDecl); 133 } else 134 return 0; 135 136 if (SS) 137 T = getQualifiedNameType(*SS, T); 138 139 return T.getAsOpaquePtr(); 140 } 141 142 return 0; 143} 144 145/// isTagName() - This method is called *for error recovery purposes only* 146/// to determine if the specified name is a valid tag name ("struct foo"). If 147/// so, this returns the TST for the tag corresponding to it (TST_enum, 148/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 149/// where the user forgot to specify the tag. 150DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 151 // Do a tag name lookup in this scope. 152 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 153 if (R.getKind() == LookupResult::Found) 154 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 155 switch (TD->getTagKind()) { 156 case TagDecl::TK_struct: return DeclSpec::TST_struct; 157 case TagDecl::TK_union: return DeclSpec::TST_union; 158 case TagDecl::TK_class: return DeclSpec::TST_class; 159 case TagDecl::TK_enum: return DeclSpec::TST_enum; 160 } 161 } 162 163 return DeclSpec::TST_unspecified; 164} 165 166 167 168DeclContext *Sema::getContainingDC(DeclContext *DC) { 169 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 170 // A C++ out-of-line method will return to the file declaration context. 171 if (MD->isOutOfLineDefinition()) 172 return MD->getLexicalDeclContext(); 173 174 // A C++ inline method is parsed *after* the topmost class it was declared 175 // in is fully parsed (it's "complete"). 176 // The parsing of a C++ inline method happens at the declaration context of 177 // the topmost (non-nested) class it is lexically declared in. 178 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 179 DC = MD->getParent(); 180 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 181 DC = RD; 182 183 // Return the declaration context of the topmost class the inline method is 184 // declared in. 185 return DC; 186 } 187 188 if (isa<ObjCMethodDecl>(DC)) 189 return Context.getTranslationUnitDecl(); 190 191 return DC->getLexicalParent(); 192} 193 194void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 195 assert(getContainingDC(DC) == CurContext && 196 "The next DeclContext should be lexically contained in the current one."); 197 CurContext = DC; 198 S->setEntity(DC); 199} 200 201void Sema::PopDeclContext() { 202 assert(CurContext && "DeclContext imbalance!"); 203 204 CurContext = getContainingDC(CurContext); 205} 206 207/// \brief Determine whether we allow overloading of the function 208/// PrevDecl with another declaration. 209/// 210/// This routine determines whether overloading is possible, not 211/// whether some new function is actually an overload. It will return 212/// true in C++ (where we can always provide overloads) or, as an 213/// extension, in C when the previous function is already an 214/// overloaded function declaration or has the "overloadable" 215/// attribute. 216static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 217 if (Context.getLangOptions().CPlusPlus) 218 return true; 219 220 if (isa<OverloadedFunctionDecl>(PrevDecl)) 221 return true; 222 223 return PrevDecl->getAttr<OverloadableAttr>() != 0; 224} 225 226/// Add this decl to the scope shadowed decl chains. 227void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 228 // Move up the scope chain until we find the nearest enclosing 229 // non-transparent context. The declaration will be introduced into this 230 // scope. 231 while (S->getEntity() && 232 ((DeclContext *)S->getEntity())->isTransparentContext()) 233 S = S->getParent(); 234 235 S->AddDecl(DeclPtrTy::make(D)); 236 237 // Add scoped declarations into their context, so that they can be 238 // found later. Declarations without a context won't be inserted 239 // into any context. 240 CurContext->addDecl(Context, D); 241 242 // C++ [basic.scope]p4: 243 // -- exactly one declaration shall declare a class name or 244 // enumeration name that is not a typedef name and the other 245 // declarations shall all refer to the same object or 246 // enumerator, or all refer to functions and function templates; 247 // in this case the class name or enumeration name is hidden. 248 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 249 // We are pushing the name of a tag (enum or class). 250 if (CurContext->getLookupContext() 251 == TD->getDeclContext()->getLookupContext()) { 252 // We're pushing the tag into the current context, which might 253 // require some reshuffling in the identifier resolver. 254 IdentifierResolver::iterator 255 I = IdResolver.begin(TD->getDeclName()), 256 IEnd = IdResolver.end(); 257 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 258 NamedDecl *PrevDecl = *I; 259 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 260 PrevDecl = *I, ++I) { 261 if (TD->declarationReplaces(*I)) { 262 // This is a redeclaration. Remove it from the chain and 263 // break out, so that we'll add in the shadowed 264 // declaration. 265 S->RemoveDecl(DeclPtrTy::make(*I)); 266 if (PrevDecl == *I) { 267 IdResolver.RemoveDecl(*I); 268 IdResolver.AddDecl(TD); 269 return; 270 } else { 271 IdResolver.RemoveDecl(*I); 272 break; 273 } 274 } 275 } 276 277 // There is already a declaration with the same name in the same 278 // scope, which is not a tag declaration. It must be found 279 // before we find the new declaration, so insert the new 280 // declaration at the end of the chain. 281 IdResolver.AddShadowedDecl(TD, PrevDecl); 282 283 return; 284 } 285 } 286 } else if (isa<FunctionDecl>(D) && 287 AllowOverloadingOfFunction(D, Context)) { 288 // We are pushing the name of a function, which might be an 289 // overloaded name. 290 FunctionDecl *FD = cast<FunctionDecl>(D); 291 IdentifierResolver::iterator Redecl 292 = std::find_if(IdResolver.begin(FD->getDeclName()), 293 IdResolver.end(), 294 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 295 FD)); 296 if (Redecl != IdResolver.end() && 297 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 298 // There is already a declaration of a function on our 299 // IdResolver chain. Replace it with this declaration. 300 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 301 IdResolver.RemoveDecl(*Redecl); 302 } 303 } else if (isa<ObjCInterfaceDecl>(D)) { 304 // We're pushing an Objective-C interface into the current 305 // context. If there is already an alias declaration, remove it first. 306 for (IdentifierResolver::iterator 307 I = IdResolver.begin(D->getDeclName()), IEnd = IdResolver.end(); 308 I != IEnd; ++I) { 309 if (isa<ObjCCompatibleAliasDecl>(*I)) { 310 S->RemoveDecl(DeclPtrTy::make(*I)); 311 IdResolver.RemoveDecl(*I); 312 break; 313 } 314 } 315 } 316 317 IdResolver.AddDecl(D); 318} 319 320void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 321 if (S->decl_empty()) return; 322 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 323 "Scope shouldn't contain decls!"); 324 325 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 326 I != E; ++I) { 327 Decl *TmpD = (*I).getAs<Decl>(); 328 assert(TmpD && "This decl didn't get pushed??"); 329 330 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 331 NamedDecl *D = cast<NamedDecl>(TmpD); 332 333 if (!D->getDeclName()) continue; 334 335 // Remove this name from our lexical scope. 336 IdResolver.RemoveDecl(D); 337 } 338} 339 340/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 341/// return 0 if one not found. 342ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 343 // The third "scope" argument is 0 since we aren't enabling lazy built-in 344 // creation from this context. 345 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 346 347 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 348} 349 350/// getNonFieldDeclScope - Retrieves the innermost scope, starting 351/// from S, where a non-field would be declared. This routine copes 352/// with the difference between C and C++ scoping rules in structs and 353/// unions. For example, the following code is well-formed in C but 354/// ill-formed in C++: 355/// @code 356/// struct S6 { 357/// enum { BAR } e; 358/// }; 359/// 360/// void test_S6() { 361/// struct S6 a; 362/// a.e = BAR; 363/// } 364/// @endcode 365/// For the declaration of BAR, this routine will return a different 366/// scope. The scope S will be the scope of the unnamed enumeration 367/// within S6. In C++, this routine will return the scope associated 368/// with S6, because the enumeration's scope is a transparent 369/// context but structures can contain non-field names. In C, this 370/// routine will return the translation unit scope, since the 371/// enumeration's scope is a transparent context and structures cannot 372/// contain non-field names. 373Scope *Sema::getNonFieldDeclScope(Scope *S) { 374 while (((S->getFlags() & Scope::DeclScope) == 0) || 375 (S->getEntity() && 376 ((DeclContext *)S->getEntity())->isTransparentContext()) || 377 (S->isClassScope() && !getLangOptions().CPlusPlus)) 378 S = S->getParent(); 379 return S; 380} 381 382void Sema::InitBuiltinVaListType() { 383 if (!Context.getBuiltinVaListType().isNull()) 384 return; 385 386 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 387 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 388 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 389 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 390} 391 392/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 393/// file scope. lazily create a decl for it. ForRedeclaration is true 394/// if we're creating this built-in in anticipation of redeclaring the 395/// built-in. 396NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 397 Scope *S, bool ForRedeclaration, 398 SourceLocation Loc) { 399 Builtin::ID BID = (Builtin::ID)bid; 400 401 if (Context.BuiltinInfo.hasVAListUse(BID)) 402 InitBuiltinVaListType(); 403 404 Builtin::Context::GetBuiltinTypeError Error; 405 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 406 switch (Error) { 407 case Builtin::Context::GE_None: 408 // Okay 409 break; 410 411 case Builtin::Context::GE_Missing_FILE: 412 if (ForRedeclaration) 413 Diag(Loc, diag::err_implicit_decl_requires_stdio) 414 << Context.BuiltinInfo.GetName(BID); 415 return 0; 416 } 417 418 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 419 Diag(Loc, diag::ext_implicit_lib_function_decl) 420 << Context.BuiltinInfo.GetName(BID) 421 << R; 422 if (Context.BuiltinInfo.getHeaderName(BID) && 423 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 424 != Diagnostic::Ignored) 425 Diag(Loc, diag::note_please_include_header) 426 << Context.BuiltinInfo.getHeaderName(BID) 427 << Context.BuiltinInfo.GetName(BID); 428 } 429 430 FunctionDecl *New = FunctionDecl::Create(Context, 431 Context.getTranslationUnitDecl(), 432 Loc, II, R, 433 FunctionDecl::Extern, false, 434 /*hasPrototype=*/true); 435 New->setImplicit(); 436 437 // Create Decl objects for each parameter, adding them to the 438 // FunctionDecl. 439 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 440 llvm::SmallVector<ParmVarDecl*, 16> Params; 441 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 442 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 443 FT->getArgType(i), VarDecl::None, 0)); 444 New->setParams(Context, &Params[0], Params.size()); 445 } 446 447 AddKnownFunctionAttributes(New); 448 449 // TUScope is the translation-unit scope to insert this function into. 450 // FIXME: This is hideous. We need to teach PushOnScopeChains to 451 // relate Scopes to DeclContexts, and probably eliminate CurContext 452 // entirely, but we're not there yet. 453 DeclContext *SavedContext = CurContext; 454 CurContext = Context.getTranslationUnitDecl(); 455 PushOnScopeChains(New, TUScope); 456 CurContext = SavedContext; 457 return New; 458} 459 460/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 461/// everything from the standard library is defined. 462NamespaceDecl *Sema::GetStdNamespace() { 463 if (!StdNamespace) { 464 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 465 DeclContext *Global = Context.getTranslationUnitDecl(); 466 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 467 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 468 } 469 return StdNamespace; 470} 471 472/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 473/// same name and scope as a previous declaration 'Old'. Figure out 474/// how to resolve this situation, merging decls or emitting 475/// diagnostics as appropriate. If there was an error, set New to be invalid. 476/// 477void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 478 // If either decl is known invalid already, set the new one to be invalid and 479 // don't bother doing any merging checks. 480 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 481 return New->setInvalidDecl(); 482 483 bool objc_types = false; 484 485 // Allow multiple definitions for ObjC built-in typedefs. 486 // FIXME: Verify the underlying types are equivalent! 487 if (getLangOptions().ObjC1) { 488 const IdentifierInfo *TypeID = New->getIdentifier(); 489 switch (TypeID->getLength()) { 490 default: break; 491 case 2: 492 if (!TypeID->isStr("id")) 493 break; 494 Context.setObjCIdType(Context.getTypeDeclType(New)); 495 objc_types = true; 496 break; 497 case 5: 498 if (!TypeID->isStr("Class")) 499 break; 500 Context.setObjCClassType(Context.getTypeDeclType(New)); 501 return; 502 case 3: 503 if (!TypeID->isStr("SEL")) 504 break; 505 Context.setObjCSelType(Context.getTypeDeclType(New)); 506 return; 507 case 8: 508 if (!TypeID->isStr("Protocol")) 509 break; 510 Context.setObjCProtoType(New->getUnderlyingType()); 511 return; 512 } 513 // Fall through - the typedef name was not a builtin type. 514 } 515 // Verify the old decl was also a type. 516 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 517 if (!Old) { 518 Diag(New->getLocation(), diag::err_redefinition_different_kind) 519 << New->getDeclName(); 520 if (OldD->getLocation().isValid()) 521 Diag(OldD->getLocation(), diag::note_previous_definition); 522 return New->setInvalidDecl(); 523 } 524 525 // Determine the "old" type we'll use for checking and diagnostics. 526 QualType OldType; 527 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 528 OldType = OldTypedef->getUnderlyingType(); 529 else 530 OldType = Context.getTypeDeclType(Old); 531 532 // If the typedef types are not identical, reject them in all languages and 533 // with any extensions enabled. 534 535 if (OldType != New->getUnderlyingType() && 536 Context.getCanonicalType(OldType) != 537 Context.getCanonicalType(New->getUnderlyingType())) { 538 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 539 << New->getUnderlyingType() << OldType; 540 if (Old->getLocation().isValid()) 541 Diag(Old->getLocation(), diag::note_previous_definition); 542 return New->setInvalidDecl(); 543 } 544 545 if (objc_types || getLangOptions().Microsoft) 546 return; 547 548 // C++ [dcl.typedef]p2: 549 // In a given non-class scope, a typedef specifier can be used to 550 // redefine the name of any type declared in that scope to refer 551 // to the type to which it already refers. 552 if (getLangOptions().CPlusPlus) { 553 if (!isa<CXXRecordDecl>(CurContext)) 554 return; 555 Diag(New->getLocation(), diag::err_redefinition) 556 << New->getDeclName(); 557 Diag(Old->getLocation(), diag::note_previous_definition); 558 return New->setInvalidDecl(); 559 } 560 561 // If we have a redefinition of a typedef in C, emit a warning. This warning 562 // is normally mapped to an error, but can be controlled with 563 // -Wtypedef-redefinition. If either the original was in a system header, 564 // don't emit this for compatibility with GCC. 565 if (PP.getDiagnostics().getSuppressSystemWarnings() && 566 Context.getSourceManager().isInSystemHeader(Old->getLocation())) 567 return; 568 569 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 570 << New->getDeclName(); 571 Diag(Old->getLocation(), diag::note_previous_definition); 572 return; 573} 574 575/// DeclhasAttr - returns true if decl Declaration already has the target 576/// attribute. 577static bool DeclHasAttr(const Decl *decl, const Attr *target) { 578 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 579 if (attr->getKind() == target->getKind()) 580 return true; 581 582 return false; 583} 584 585/// MergeAttributes - append attributes from the Old decl to the New one. 586static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 587 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 588 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 589 Attr *NewAttr = attr->clone(C); 590 NewAttr->setInherited(true); 591 New->addAttr(NewAttr); 592 } 593 } 594} 595 596/// Used in MergeFunctionDecl to keep track of function parameters in 597/// C. 598struct GNUCompatibleParamWarning { 599 ParmVarDecl *OldParm; 600 ParmVarDecl *NewParm; 601 QualType PromotedType; 602}; 603 604/// MergeFunctionDecl - We just parsed a function 'New' from 605/// declarator D which has the same name and scope as a previous 606/// declaration 'Old'. Figure out how to resolve this situation, 607/// merging decls or emitting diagnostics as appropriate. 608/// 609/// In C++, New and Old must be declarations that are not 610/// overloaded. Use IsOverload to determine whether New and Old are 611/// overloaded, and to select the Old declaration that New should be 612/// merged with. 613/// 614/// Returns true if there was an error, false otherwise. 615bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 616 assert(!isa<OverloadedFunctionDecl>(OldD) && 617 "Cannot merge with an overloaded function declaration"); 618 619 // Verify the old decl was also a function. 620 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 621 if (!Old) { 622 Diag(New->getLocation(), diag::err_redefinition_different_kind) 623 << New->getDeclName(); 624 Diag(OldD->getLocation(), diag::note_previous_definition); 625 return true; 626 } 627 628 // Determine whether the previous declaration was a definition, 629 // implicit declaration, or a declaration. 630 diag::kind PrevDiag; 631 if (Old->isThisDeclarationADefinition()) 632 PrevDiag = diag::note_previous_definition; 633 else if (Old->isImplicit()) 634 PrevDiag = diag::note_previous_implicit_declaration; 635 else 636 PrevDiag = diag::note_previous_declaration; 637 638 QualType OldQType = Context.getCanonicalType(Old->getType()); 639 QualType NewQType = Context.getCanonicalType(New->getType()); 640 641 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 642 New->getStorageClass() == FunctionDecl::Static && 643 Old->getStorageClass() != FunctionDecl::Static) { 644 Diag(New->getLocation(), diag::err_static_non_static) 645 << New; 646 Diag(Old->getLocation(), PrevDiag); 647 return true; 648 } 649 650 if (getLangOptions().CPlusPlus) { 651 // (C++98 13.1p2): 652 // Certain function declarations cannot be overloaded: 653 // -- Function declarations that differ only in the return type 654 // cannot be overloaded. 655 QualType OldReturnType 656 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 657 QualType NewReturnType 658 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 659 if (OldReturnType != NewReturnType) { 660 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 661 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 662 return true; 663 } 664 665 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 666 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 667 if (OldMethod && NewMethod && 668 OldMethod->getLexicalDeclContext() == 669 NewMethod->getLexicalDeclContext()) { 670 // -- Member function declarations with the same name and the 671 // same parameter types cannot be overloaded if any of them 672 // is a static member function declaration. 673 if (OldMethod->isStatic() || NewMethod->isStatic()) { 674 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 675 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 676 return true; 677 } 678 679 // C++ [class.mem]p1: 680 // [...] A member shall not be declared twice in the 681 // member-specification, except that a nested class or member 682 // class template can be declared and then later defined. 683 unsigned NewDiag; 684 if (isa<CXXConstructorDecl>(OldMethod)) 685 NewDiag = diag::err_constructor_redeclared; 686 else if (isa<CXXDestructorDecl>(NewMethod)) 687 NewDiag = diag::err_destructor_redeclared; 688 else if (isa<CXXConversionDecl>(NewMethod)) 689 NewDiag = diag::err_conv_function_redeclared; 690 else 691 NewDiag = diag::err_member_redeclared; 692 693 Diag(New->getLocation(), NewDiag); 694 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 695 } 696 697 // (C++98 8.3.5p3): 698 // All declarations for a function shall agree exactly in both the 699 // return type and the parameter-type-list. 700 if (OldQType == NewQType) 701 return MergeCompatibleFunctionDecls(New, Old); 702 703 // Fall through for conflicting redeclarations and redefinitions. 704 } 705 706 // C: Function types need to be compatible, not identical. This handles 707 // duplicate function decls like "void f(int); void f(enum X);" properly. 708 if (!getLangOptions().CPlusPlus && 709 Context.typesAreCompatible(OldQType, NewQType)) { 710 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 711 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 712 const FunctionProtoType *OldProto = 0; 713 if (isa<FunctionNoProtoType>(NewFuncType) && 714 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 715 // The old declaration provided a function prototype, but the 716 // new declaration does not. Merge in the prototype. 717 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 Old->hasPrototype() && !New->hasPrototype() && 754 New->getType()->getAsFunctionProtoType() && 755 Old->getNumParams() == New->getNumParams()) { 756 llvm::SmallVector<QualType, 16> ArgTypes; 757 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 758 const FunctionProtoType *OldProto 759 = Old->getType()->getAsFunctionProtoType(); 760 const FunctionProtoType *NewProto 761 = New->getType()->getAsFunctionProtoType(); 762 763 // Determine whether this is the GNU C extension. 764 bool GNUCompatible = 765 Context.typesAreCompatible(OldProto->getResultType(), 766 NewProto->getResultType()) && 767 (OldProto->isVariadic() == NewProto->isVariadic()); 768 for (unsigned Idx = 0, End = Old->getNumParams(); 769 GNUCompatible && Idx != End; ++Idx) { 770 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 771 ParmVarDecl *NewParm = New->getParamDecl(Idx); 772 if (Context.typesAreCompatible(OldParm->getType(), 773 NewProto->getArgType(Idx))) { 774 ArgTypes.push_back(NewParm->getType()); 775 } else if (Context.typesAreCompatible(OldParm->getType(), 776 NewParm->getType())) { 777 GNUCompatibleParamWarning Warn 778 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 779 Warnings.push_back(Warn); 780 ArgTypes.push_back(NewParm->getType()); 781 } else 782 GNUCompatible = false; 783 } 784 785 if (GNUCompatible) { 786 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 787 Diag(Warnings[Warn].NewParm->getLocation(), 788 diag::ext_param_promoted_not_compatible_with_prototype) 789 << Warnings[Warn].PromotedType 790 << Warnings[Warn].OldParm->getType(); 791 Diag(Warnings[Warn].OldParm->getLocation(), 792 diag::note_previous_declaration); 793 } 794 795 New->setType(Context.getFunctionType(NewProto->getResultType(), 796 &ArgTypes[0], ArgTypes.size(), 797 NewProto->isVariadic(), 798 NewProto->getTypeQuals())); 799 return MergeCompatibleFunctionDecls(New, Old); 800 } 801 802 // Fall through to diagnose conflicting types. 803 } 804 805 // A function that has already been declared has been redeclared or defined 806 // with a different type- show appropriate diagnostic 807 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 808 // The user has declared a builtin function with an incompatible 809 // signature. 810 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 811 // The function the user is redeclaring is a library-defined 812 // function like 'malloc' or 'printf'. Warn about the 813 // redeclaration, then pretend that we don't know about this 814 // library built-in. 815 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 816 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 817 << Old << Old->getType(); 818 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 819 Old->setInvalidDecl(); 820 return false; 821 } 822 823 PrevDiag = diag::note_previous_builtin_declaration; 824 } 825 826 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 827 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 828 return true; 829} 830 831/// \brief Completes the merge of two function declarations that are 832/// known to be compatible. 833/// 834/// This routine handles the merging of attributes and other 835/// properties of function declarations form the old declaration to 836/// the new declaration, once we know that New is in fact a 837/// redeclaration of Old. 838/// 839/// \returns false 840bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 841 // Merge the attributes 842 MergeAttributes(New, Old, Context); 843 844 // Merge the storage class. 845 if (Old->getStorageClass() != FunctionDecl::Extern) 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/// 886void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 887 // If either decl is invalid, make sure the new one is marked invalid and 888 // don't do any other checking. 889 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 890 return New->setInvalidDecl(); 891 892 // Verify the old decl was also a variable. 893 VarDecl *Old = dyn_cast<VarDecl>(OldD); 894 if (!Old) { 895 Diag(New->getLocation(), diag::err_redefinition_different_kind) 896 << New->getDeclName(); 897 Diag(OldD->getLocation(), diag::note_previous_definition); 898 return New->setInvalidDecl(); 899 } 900 901 MergeAttributes(New, Old, Context); 902 903 // Merge the types 904 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 905 if (MergedT.isNull()) { 906 Diag(New->getLocation(), diag::err_redefinition_different_type) 907 << New->getDeclName(); 908 Diag(Old->getLocation(), diag::note_previous_definition); 909 return New->setInvalidDecl(); 910 } 911 New->setType(MergedT); 912 913 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 914 if (New->getStorageClass() == VarDecl::Static && 915 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 916 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 917 Diag(Old->getLocation(), diag::note_previous_definition); 918 return New->setInvalidDecl(); 919 } 920 // C99 6.2.2p4: 921 // For an identifier declared with the storage-class specifier 922 // extern in a scope in which a prior declaration of that 923 // identifier is visible,23) if the prior declaration specifies 924 // internal or external linkage, the linkage of the identifier at 925 // the later declaration is the same as the linkage specified at 926 // the prior declaration. If no prior declaration is visible, or 927 // if the prior declaration specifies no linkage, then the 928 // identifier has external linkage. 929 if (New->hasExternalStorage() && Old->hasLinkage()) 930 /* Okay */; 931 else if (New->getStorageClass() != VarDecl::Static && 932 Old->getStorageClass() == VarDecl::Static) { 933 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 934 Diag(Old->getLocation(), diag::note_previous_definition); 935 return New->setInvalidDecl(); 936 } 937 938 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 939 940 // FIXME: The test for external storage here seems wrong? We still 941 // need to check for mismatches. 942 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 943 // Don't complain about out-of-line definitions of static members. 944 !(Old->getLexicalDeclContext()->isRecord() && 945 !New->getLexicalDeclContext()->isRecord())) { 946 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 947 Diag(Old->getLocation(), diag::note_previous_definition); 948 return New->setInvalidDecl(); 949 } 950 951 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 952 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 953 Diag(Old->getLocation(), diag::note_previous_definition); 954 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 955 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 956 Diag(Old->getLocation(), diag::note_previous_definition); 957 } 958 959 // Keep a chain of previous declarations. 960 New->setPreviousDeclaration(Old); 961} 962 963/// CheckParmsForFunctionDef - Check that the parameters of the given 964/// function are appropriate for the definition of a function. This 965/// takes care of any checks that cannot be performed on the 966/// declaration itself, e.g., that the types of each of the function 967/// parameters are complete. 968bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 969 bool HasInvalidParm = false; 970 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 971 ParmVarDecl *Param = FD->getParamDecl(p); 972 973 // C99 6.7.5.3p4: the parameters in a parameter type list in a 974 // function declarator that is part of a function definition of 975 // that function shall not have incomplete type. 976 // 977 // This is also C++ [dcl.fct]p6. 978 if (!Param->isInvalidDecl() && 979 RequireCompleteType(Param->getLocation(), Param->getType(), 980 diag::err_typecheck_decl_incomplete_type)) { 981 Param->setInvalidDecl(); 982 HasInvalidParm = true; 983 } 984 985 // C99 6.9.1p5: If the declarator includes a parameter type list, the 986 // declaration of each parameter shall include an identifier. 987 if (Param->getIdentifier() == 0 && 988 !Param->isImplicit() && 989 !getLangOptions().CPlusPlus) 990 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 991 } 992 993 return HasInvalidParm; 994} 995 996/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 997/// no declarator (e.g. "struct foo;") is parsed. 998Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 999 // FIXME: Error on auto/register at file scope 1000 // FIXME: Error on inline/virtual/explicit 1001 // FIXME: Error on invalid restrict 1002 // FIXME: Warn on useless __thread 1003 // FIXME: Warn on useless const/volatile 1004 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1005 // FIXME: Warn on useless attributes 1006 1007 TagDecl *Tag = 0; 1008 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1009 DS.getTypeSpecType() == DeclSpec::TST_struct || 1010 DS.getTypeSpecType() == DeclSpec::TST_union || 1011 DS.getTypeSpecType() == DeclSpec::TST_enum) 1012 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 1013 1014 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1015 if (!Record->getDeclName() && Record->isDefinition() && 1016 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1017 if (getLangOptions().CPlusPlus || 1018 Record->getDeclContext()->isRecord()) 1019 return BuildAnonymousStructOrUnion(S, DS, Record); 1020 1021 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1022 << DS.getSourceRange(); 1023 } 1024 1025 // Microsoft allows unnamed struct/union fields. Don't complain 1026 // about them. 1027 // FIXME: Should we support Microsoft's extensions in this area? 1028 if (Record->getDeclName() && getLangOptions().Microsoft) 1029 return DeclPtrTy::make(Tag); 1030 } 1031 1032 if (!DS.isMissingDeclaratorOk() && 1033 DS.getTypeSpecType() != DeclSpec::TST_error) { 1034 // Warn about typedefs of enums without names, since this is an 1035 // extension in both Microsoft an GNU. 1036 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1037 Tag && isa<EnumDecl>(Tag)) { 1038 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1039 << DS.getSourceRange(); 1040 return DeclPtrTy::make(Tag); 1041 } 1042 1043 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1044 << DS.getSourceRange(); 1045 return DeclPtrTy(); 1046 } 1047 1048 return DeclPtrTy::make(Tag); 1049} 1050 1051/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1052/// anonymous struct or union AnonRecord into the owning context Owner 1053/// and scope S. This routine will be invoked just after we realize 1054/// that an unnamed union or struct is actually an anonymous union or 1055/// struct, e.g., 1056/// 1057/// @code 1058/// union { 1059/// int i; 1060/// float f; 1061/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1062/// // f into the surrounding scope.x 1063/// @endcode 1064/// 1065/// This routine is recursive, injecting the names of nested anonymous 1066/// structs/unions into the owning context and scope as well. 1067bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1068 RecordDecl *AnonRecord) { 1069 bool Invalid = false; 1070 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1071 FEnd = AnonRecord->field_end(Context); 1072 F != FEnd; ++F) { 1073 if ((*F)->getDeclName()) { 1074 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1075 LookupOrdinaryName, true); 1076 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1077 // C++ [class.union]p2: 1078 // The names of the members of an anonymous union shall be 1079 // distinct from the names of any other entity in the 1080 // scope in which the anonymous union is declared. 1081 unsigned diagKind 1082 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1083 : diag::err_anonymous_struct_member_redecl; 1084 Diag((*F)->getLocation(), diagKind) 1085 << (*F)->getDeclName(); 1086 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1087 Invalid = true; 1088 } else { 1089 // C++ [class.union]p2: 1090 // For the purpose of name lookup, after the anonymous union 1091 // definition, the members of the anonymous union are 1092 // considered to have been defined in the scope in which the 1093 // anonymous union is declared. 1094 Owner->makeDeclVisibleInContext(Context, *F); 1095 S->AddDecl(DeclPtrTy::make(*F)); 1096 IdResolver.AddDecl(*F); 1097 } 1098 } else if (const RecordType *InnerRecordType 1099 = (*F)->getType()->getAsRecordType()) { 1100 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1101 if (InnerRecord->isAnonymousStructOrUnion()) 1102 Invalid = Invalid || 1103 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1104 } 1105 } 1106 1107 return Invalid; 1108} 1109 1110/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1111/// anonymous structure or union. Anonymous unions are a C++ feature 1112/// (C++ [class.union]) and a GNU C extension; anonymous structures 1113/// are a GNU C and GNU C++ extension. 1114Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1115 RecordDecl *Record) { 1116 DeclContext *Owner = Record->getDeclContext(); 1117 1118 // Diagnose whether this anonymous struct/union is an extension. 1119 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1120 Diag(Record->getLocation(), diag::ext_anonymous_union); 1121 else if (!Record->isUnion()) 1122 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1123 1124 // C and C++ require different kinds of checks for anonymous 1125 // structs/unions. 1126 bool Invalid = false; 1127 if (getLangOptions().CPlusPlus) { 1128 const char* PrevSpec = 0; 1129 // C++ [class.union]p3: 1130 // Anonymous unions declared in a named namespace or in the 1131 // global namespace shall be declared static. 1132 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1133 (isa<TranslationUnitDecl>(Owner) || 1134 (isa<NamespaceDecl>(Owner) && 1135 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1136 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1137 Invalid = true; 1138 1139 // Recover by adding 'static'. 1140 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1141 } 1142 // C++ [class.union]p3: 1143 // A storage class is not allowed in a declaration of an 1144 // anonymous union in a class scope. 1145 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1146 isa<RecordDecl>(Owner)) { 1147 Diag(DS.getStorageClassSpecLoc(), 1148 diag::err_anonymous_union_with_storage_spec); 1149 Invalid = true; 1150 1151 // Recover by removing the storage specifier. 1152 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1153 PrevSpec); 1154 } 1155 1156 // C++ [class.union]p2: 1157 // The member-specification of an anonymous union shall only 1158 // define non-static data members. [Note: nested types and 1159 // functions cannot be declared within an anonymous union. ] 1160 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1161 MemEnd = Record->decls_end(Context); 1162 Mem != MemEnd; ++Mem) { 1163 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1164 // C++ [class.union]p3: 1165 // An anonymous union shall not have private or protected 1166 // members (clause 11). 1167 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1168 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1169 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1170 Invalid = true; 1171 } 1172 } else if ((*Mem)->isImplicit()) { 1173 // Any implicit members are fine. 1174 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1175 // This is a type that showed up in an 1176 // elaborated-type-specifier inside the anonymous struct or 1177 // union, but which actually declares a type outside of the 1178 // anonymous struct or union. It's okay. 1179 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1180 if (!MemRecord->isAnonymousStructOrUnion() && 1181 MemRecord->getDeclName()) { 1182 // This is a nested type declaration. 1183 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1184 << (int)Record->isUnion(); 1185 Invalid = true; 1186 } 1187 } else { 1188 // We have something that isn't a non-static data 1189 // member. Complain about it. 1190 unsigned DK = diag::err_anonymous_record_bad_member; 1191 if (isa<TypeDecl>(*Mem)) 1192 DK = diag::err_anonymous_record_with_type; 1193 else if (isa<FunctionDecl>(*Mem)) 1194 DK = diag::err_anonymous_record_with_function; 1195 else if (isa<VarDecl>(*Mem)) 1196 DK = diag::err_anonymous_record_with_static; 1197 Diag((*Mem)->getLocation(), DK) 1198 << (int)Record->isUnion(); 1199 Invalid = true; 1200 } 1201 } 1202 } 1203 1204 if (!Record->isUnion() && !Owner->isRecord()) { 1205 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1206 << (int)getLangOptions().CPlusPlus; 1207 Invalid = true; 1208 } 1209 1210 // Create a declaration for this anonymous struct/union. 1211 NamedDecl *Anon = 0; 1212 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1213 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1214 /*IdentifierInfo=*/0, 1215 Context.getTypeDeclType(Record), 1216 /*BitWidth=*/0, /*Mutable=*/false); 1217 Anon->setAccess(AS_public); 1218 if (getLangOptions().CPlusPlus) 1219 FieldCollector->Add(cast<FieldDecl>(Anon)); 1220 } else { 1221 VarDecl::StorageClass SC; 1222 switch (DS.getStorageClassSpec()) { 1223 default: assert(0 && "Unknown storage class!"); 1224 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1225 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1226 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1227 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1228 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1229 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1230 case DeclSpec::SCS_mutable: 1231 // mutable can only appear on non-static class members, so it's always 1232 // an error here 1233 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1234 Invalid = true; 1235 SC = VarDecl::None; 1236 break; 1237 } 1238 1239 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1240 /*IdentifierInfo=*/0, 1241 Context.getTypeDeclType(Record), 1242 SC, DS.getSourceRange().getBegin()); 1243 } 1244 Anon->setImplicit(); 1245 1246 // Add the anonymous struct/union object to the current 1247 // context. We'll be referencing this object when we refer to one of 1248 // its members. 1249 Owner->addDecl(Context, Anon); 1250 1251 // Inject the members of the anonymous struct/union into the owning 1252 // context and into the identifier resolver chain for name lookup 1253 // purposes. 1254 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1255 Invalid = true; 1256 1257 // Mark this as an anonymous struct/union type. Note that we do not 1258 // do this until after we have already checked and injected the 1259 // members of this anonymous struct/union type, because otherwise 1260 // the members could be injected twice: once by DeclContext when it 1261 // builds its lookup table, and once by 1262 // InjectAnonymousStructOrUnionMembers. 1263 Record->setAnonymousStructOrUnion(true); 1264 1265 if (Invalid) 1266 Anon->setInvalidDecl(); 1267 1268 return DeclPtrTy::make(Anon); 1269} 1270 1271 1272/// GetNameForDeclarator - Determine the full declaration name for the 1273/// given Declarator. 1274DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1275 switch (D.getKind()) { 1276 case Declarator::DK_Abstract: 1277 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1278 return DeclarationName(); 1279 1280 case Declarator::DK_Normal: 1281 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1282 return DeclarationName(D.getIdentifier()); 1283 1284 case Declarator::DK_Constructor: { 1285 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1286 Ty = Context.getCanonicalType(Ty); 1287 return Context.DeclarationNames.getCXXConstructorName(Ty); 1288 } 1289 1290 case Declarator::DK_Destructor: { 1291 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1292 Ty = Context.getCanonicalType(Ty); 1293 return Context.DeclarationNames.getCXXDestructorName(Ty); 1294 } 1295 1296 case Declarator::DK_Conversion: { 1297 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1298 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1299 Ty = Context.getCanonicalType(Ty); 1300 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1301 } 1302 1303 case Declarator::DK_Operator: 1304 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1305 return Context.DeclarationNames.getCXXOperatorName( 1306 D.getOverloadedOperator()); 1307 } 1308 1309 assert(false && "Unknown name kind"); 1310 return DeclarationName(); 1311} 1312 1313/// isNearlyMatchingFunction - Determine whether the C++ functions 1314/// Declaration and Definition are "nearly" matching. This heuristic 1315/// is used to improve diagnostics in the case where an out-of-line 1316/// function definition doesn't match any declaration within 1317/// the class or namespace. 1318static bool isNearlyMatchingFunction(ASTContext &Context, 1319 FunctionDecl *Declaration, 1320 FunctionDecl *Definition) { 1321 if (Declaration->param_size() != Definition->param_size()) 1322 return false; 1323 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1324 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1325 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1326 1327 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1328 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1329 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1330 return false; 1331 } 1332 1333 return true; 1334} 1335 1336Sema::DeclPtrTy 1337Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1338 DeclarationName Name = GetNameForDeclarator(D); 1339 1340 // All of these full declarators require an identifier. If it doesn't have 1341 // one, the ParsedFreeStandingDeclSpec action should be used. 1342 if (!Name) { 1343 if (!D.isInvalidType()) // Reject this if we think it is valid. 1344 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1345 diag::err_declarator_need_ident) 1346 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1347 return DeclPtrTy(); 1348 } 1349 1350 // The scope passed in may not be a decl scope. Zip up the scope tree until 1351 // we find one that is. 1352 while ((S->getFlags() & Scope::DeclScope) == 0 || 1353 (S->getFlags() & Scope::TemplateParamScope) != 0) 1354 S = S->getParent(); 1355 1356 DeclContext *DC; 1357 NamedDecl *PrevDecl; 1358 NamedDecl *New; 1359 1360 QualType R = GetTypeForDeclarator(D, S); 1361 1362 // See if this is a redefinition of a variable in the same scope. 1363 if (D.getCXXScopeSpec().isInvalid()) { 1364 DC = CurContext; 1365 PrevDecl = 0; 1366 D.setInvalidType(); 1367 } else if (!D.getCXXScopeSpec().isSet()) { 1368 LookupNameKind NameKind = LookupOrdinaryName; 1369 1370 // If the declaration we're planning to build will be a function 1371 // or object with linkage, then look for another declaration with 1372 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1373 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1374 /* Do nothing*/; 1375 else if (R->isFunctionType()) { 1376 if (CurContext->isFunctionOrMethod()) 1377 NameKind = LookupRedeclarationWithLinkage; 1378 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1379 NameKind = LookupRedeclarationWithLinkage; 1380 1381 DC = CurContext; 1382 PrevDecl = LookupName(S, Name, NameKind, true, 1383 D.getDeclSpec().getStorageClassSpec() != 1384 DeclSpec::SCS_static, 1385 D.getIdentifierLoc()); 1386 } else { // Something like "int foo::x;" 1387 DC = computeDeclContext(D.getCXXScopeSpec()); 1388 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1389 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1390 1391 // C++ 7.3.1.2p2: 1392 // Members (including explicit specializations of templates) of a named 1393 // namespace can also be defined outside that namespace by explicit 1394 // qualification of the name being defined, provided that the entity being 1395 // defined was already declared in the namespace and the definition appears 1396 // after the point of declaration in a namespace that encloses the 1397 // declarations namespace. 1398 // 1399 // Note that we only check the context at this point. We don't yet 1400 // have enough information to make sure that PrevDecl is actually 1401 // the declaration we want to match. For example, given: 1402 // 1403 // class X { 1404 // void f(); 1405 // void f(float); 1406 // }; 1407 // 1408 // void X::f(int) { } // ill-formed 1409 // 1410 // In this case, PrevDecl will point to the overload set 1411 // containing the two f's declared in X, but neither of them 1412 // matches. 1413 1414 // First check whether we named the global scope. 1415 if (isa<TranslationUnitDecl>(DC)) { 1416 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1417 << Name << D.getCXXScopeSpec().getRange(); 1418 } else if (!CurContext->Encloses(DC)) { 1419 // The qualifying scope doesn't enclose the original declaration. 1420 // Emit diagnostic based on current scope. 1421 SourceLocation L = D.getIdentifierLoc(); 1422 SourceRange R = D.getCXXScopeSpec().getRange(); 1423 if (isa<FunctionDecl>(CurContext)) 1424 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1425 else 1426 Diag(L, diag::err_invalid_declarator_scope) 1427 << Name << cast<NamedDecl>(DC) << R; 1428 D.setInvalidType(); 1429 } 1430 } 1431 1432 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1433 // Maybe we will complain about the shadowed template parameter. 1434 if (!D.isInvalidType()) 1435 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1436 D.setInvalidType(); 1437 1438 // Just pretend that we didn't see the previous declaration. 1439 PrevDecl = 0; 1440 } 1441 1442 // In C++, the previous declaration we find might be a tag type 1443 // (class or enum). In this case, the new declaration will hide the 1444 // tag type. Note that this does does not apply if we're declaring a 1445 // typedef (C++ [dcl.typedef]p4). 1446 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1447 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1448 PrevDecl = 0; 1449 1450 bool Redeclaration = false; 1451 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1452 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1453 } else if (R->isFunctionType()) { 1454 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1455 IsFunctionDefinition, Redeclaration); 1456 } else { 1457 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, Redeclaration); 1458 } 1459 1460 if (New == 0) 1461 return DeclPtrTy(); 1462 1463 // If this has an identifier and is not an invalid redeclaration, 1464 // add it to the scope stack. 1465 if (Name && !(Redeclaration && New->isInvalidDecl())) 1466 PushOnScopeChains(New, S); 1467 1468 return DeclPtrTy::make(New); 1469} 1470 1471/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1472/// types into constant array types in certain situations which would otherwise 1473/// be errors (for GCC compatibility). 1474static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1475 ASTContext &Context, 1476 bool &SizeIsNegative) { 1477 // This method tries to turn a variable array into a constant 1478 // array even when the size isn't an ICE. This is necessary 1479 // for compatibility with code that depends on gcc's buggy 1480 // constant expression folding, like struct {char x[(int)(char*)2];} 1481 SizeIsNegative = false; 1482 1483 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1484 QualType Pointee = PTy->getPointeeType(); 1485 QualType FixedType = 1486 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1487 if (FixedType.isNull()) return FixedType; 1488 FixedType = Context.getPointerType(FixedType); 1489 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1490 return FixedType; 1491 } 1492 1493 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1494 if (!VLATy) 1495 return QualType(); 1496 // FIXME: We should probably handle this case 1497 if (VLATy->getElementType()->isVariablyModifiedType()) 1498 return QualType(); 1499 1500 Expr::EvalResult EvalResult; 1501 if (!VLATy->getSizeExpr() || 1502 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1503 !EvalResult.Val.isInt()) 1504 return QualType(); 1505 1506 llvm::APSInt &Res = EvalResult.Val.getInt(); 1507 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1508 return Context.getConstantArrayType(VLATy->getElementType(), 1509 Res, ArrayType::Normal, 0); 1510 1511 SizeIsNegative = true; 1512 return QualType(); 1513} 1514 1515/// \brief Register the given locally-scoped external C declaration so 1516/// that it can be found later for redeclarations 1517void 1518Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1519 Scope *S) { 1520 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1521 "Decl is not a locally-scoped decl!"); 1522 // Note that we have a locally-scoped external with this name. 1523 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1524 1525 if (!PrevDecl) 1526 return; 1527 1528 // If there was a previous declaration of this variable, it may be 1529 // in our identifier chain. Update the identifier chain with the new 1530 // declaration. 1531 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1532 // The previous declaration was found on the identifer resolver 1533 // chain, so remove it from its scope. 1534 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1535 S = S->getParent(); 1536 1537 if (S) 1538 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1539 } 1540} 1541 1542/// \brief Diagnose function specifiers on a declaration of an identifier that 1543/// does not identify a function. 1544void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1545 // FIXME: We should probably indicate the identifier in question to avoid 1546 // confusion for constructs like "inline int a(), b;" 1547 if (D.getDeclSpec().isInlineSpecified()) 1548 Diag(D.getDeclSpec().getInlineSpecLoc(), 1549 diag::err_inline_non_function); 1550 1551 if (D.getDeclSpec().isVirtualSpecified()) 1552 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1553 diag::err_virtual_non_function); 1554 1555 if (D.getDeclSpec().isExplicitSpecified()) 1556 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1557 diag::err_explicit_non_function); 1558} 1559 1560NamedDecl* 1561Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1562 QualType R, Decl* PrevDecl, bool &Redeclaration) { 1563 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1564 if (D.getCXXScopeSpec().isSet()) { 1565 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1566 << D.getCXXScopeSpec().getRange(); 1567 D.setInvalidType(); 1568 // Pretend we didn't see the scope specifier. 1569 DC = 0; 1570 } 1571 1572 if (getLangOptions().CPlusPlus) { 1573 // Check that there are no default arguments (C++ only). 1574 CheckExtraCXXDefaultArguments(D); 1575 } 1576 1577 DiagnoseFunctionSpecifiers(D); 1578 1579 if (D.getDeclSpec().isThreadSpecified()) 1580 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1581 1582 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1583 if (!NewTD) return 0; 1584 1585 if (D.isInvalidType()) 1586 NewTD->setInvalidDecl(); 1587 1588 // Handle attributes prior to checking for duplicates in MergeVarDecl 1589 ProcessDeclAttributes(NewTD, D); 1590 // Merge the decl with the existing one if appropriate. If the decl is 1591 // in an outer scope, it isn't the same thing. 1592 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1593 Redeclaration = true; 1594 MergeTypeDefDecl(NewTD, PrevDecl); 1595 } 1596 1597 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1598 // then it shall have block scope. 1599 QualType T = NewTD->getUnderlyingType(); 1600 if (T->isVariablyModifiedType()) { 1601 CurFunctionNeedsScopeChecking = true; 1602 1603 if (S->getFnParent() == 0) { 1604 bool SizeIsNegative; 1605 QualType FixedTy = 1606 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1607 if (!FixedTy.isNull()) { 1608 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1609 NewTD->setUnderlyingType(FixedTy); 1610 } else { 1611 if (SizeIsNegative) 1612 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1613 else if (T->isVariableArrayType()) 1614 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1615 else 1616 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1617 NewTD->setInvalidDecl(); 1618 } 1619 } 1620 } 1621 return NewTD; 1622} 1623 1624/// \brief Determines whether the given declaration is an out-of-scope 1625/// previous declaration. 1626/// 1627/// This routine should be invoked when name lookup has found a 1628/// previous declaration (PrevDecl) that is not in the scope where a 1629/// new declaration by the same name is being introduced. If the new 1630/// declaration occurs in a local scope, previous declarations with 1631/// linkage may still be considered previous declarations (C99 1632/// 6.2.2p4-5, C++ [basic.link]p6). 1633/// 1634/// \param PrevDecl the previous declaration found by name 1635/// lookup 1636/// 1637/// \param DC the context in which the new declaration is being 1638/// declared. 1639/// 1640/// \returns true if PrevDecl is an out-of-scope previous declaration 1641/// for a new delcaration with the same name. 1642static bool 1643isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1644 ASTContext &Context) { 1645 if (!PrevDecl) 1646 return 0; 1647 1648 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1649 // case we need to check each of the overloaded functions. 1650 if (!PrevDecl->hasLinkage()) 1651 return false; 1652 1653 if (Context.getLangOptions().CPlusPlus) { 1654 // C++ [basic.link]p6: 1655 // If there is a visible declaration of an entity with linkage 1656 // having the same name and type, ignoring entities declared 1657 // outside the innermost enclosing namespace scope, the block 1658 // scope declaration declares that same entity and receives the 1659 // linkage of the previous declaration. 1660 DeclContext *OuterContext = DC->getLookupContext(); 1661 if (!OuterContext->isFunctionOrMethod()) 1662 // This rule only applies to block-scope declarations. 1663 return false; 1664 else { 1665 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1666 if (PrevOuterContext->isRecord()) 1667 // We found a member function: ignore it. 1668 return false; 1669 else { 1670 // Find the innermost enclosing namespace for the new and 1671 // previous declarations. 1672 while (!OuterContext->isFileContext()) 1673 OuterContext = OuterContext->getParent(); 1674 while (!PrevOuterContext->isFileContext()) 1675 PrevOuterContext = PrevOuterContext->getParent(); 1676 1677 // The previous declaration is in a different namespace, so it 1678 // isn't the same function. 1679 if (OuterContext->getPrimaryContext() != 1680 PrevOuterContext->getPrimaryContext()) 1681 return false; 1682 } 1683 } 1684 } 1685 1686 return true; 1687} 1688 1689NamedDecl* 1690Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1691 QualType R,NamedDecl* PrevDecl, 1692 bool &Redeclaration) { 1693 DeclarationName Name = GetNameForDeclarator(D); 1694 1695 // Check that there are no default arguments (C++ only). 1696 if (getLangOptions().CPlusPlus) 1697 CheckExtraCXXDefaultArguments(D); 1698 1699 VarDecl *NewVD; 1700 VarDecl::StorageClass SC; 1701 switch (D.getDeclSpec().getStorageClassSpec()) { 1702 default: assert(0 && "Unknown storage class!"); 1703 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1704 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1705 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1706 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1707 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1708 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1709 case DeclSpec::SCS_mutable: 1710 // mutable can only appear on non-static class members, so it's always 1711 // an error here 1712 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1713 D.setInvalidType(); 1714 SC = VarDecl::None; 1715 break; 1716 } 1717 1718 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1719 if (!II) { 1720 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1721 << Name.getAsString(); 1722 return 0; 1723 } 1724 1725 DiagnoseFunctionSpecifiers(D); 1726 1727 if (!DC->isRecord() && S->getFnParent() == 0) { 1728 // C99 6.9p2: The storage-class specifiers auto and register shall not 1729 // appear in the declaration specifiers in an external declaration. 1730 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1731 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1732 D.setInvalidType(); 1733 } 1734 } 1735 if (DC->isRecord() && !CurContext->isRecord()) { 1736 // This is an out-of-line definition of a static data member. 1737 if (SC == VarDecl::Static) { 1738 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1739 diag::err_static_out_of_line) 1740 << CodeModificationHint::CreateRemoval( 1741 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1742 } else if (SC == VarDecl::None) 1743 SC = VarDecl::Static; 1744 } 1745 1746 // The variable can not 1747 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1748 II, R, SC, 1749 // FIXME: Move to DeclGroup... 1750 D.getDeclSpec().getSourceRange().getBegin()); 1751 1752 if (D.isInvalidType()) 1753 NewVD->setInvalidDecl(); 1754 1755 if (D.getDeclSpec().isThreadSpecified()) { 1756 if (NewVD->hasLocalStorage()) 1757 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 1758 else if (!Context.Target.isTLSSupported()) 1759 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 1760 else 1761 NewVD->setThreadSpecified(true); 1762 } 1763 1764 // Set the lexical context. If the declarator has a C++ scope specifier, the 1765 // lexical context will be different from the semantic context. 1766 NewVD->setLexicalDeclContext(CurContext); 1767 1768 // Handle attributes prior to checking for duplicates in MergeVarDecl 1769 ProcessDeclAttributes(NewVD, D); 1770 1771 // Handle GNU asm-label extension (encoded as an attribute). 1772 if (Expr *E = (Expr*) D.getAsmLabel()) { 1773 // The parser guarantees this is a string. 1774 StringLiteral *SE = cast<StringLiteral>(E); 1775 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1776 SE->getByteLength()))); 1777 } 1778 1779 // If name lookup finds a previous declaration that is not in the 1780 // same scope as the new declaration, this may still be an 1781 // acceptable redeclaration. 1782 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1783 !(NewVD->hasLinkage() && 1784 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1785 PrevDecl = 0; 1786 1787 // Merge the decl with the existing one if appropriate. 1788 if (PrevDecl) { 1789 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1790 // The user tried to define a non-static data member 1791 // out-of-line (C++ [dcl.meaning]p1). 1792 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1793 << D.getCXXScopeSpec().getRange(); 1794 PrevDecl = 0; 1795 NewVD->setInvalidDecl(); 1796 } 1797 } else if (D.getCXXScopeSpec().isSet()) { 1798 // No previous declaration in the qualifying scope. 1799 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1800 << Name << D.getCXXScopeSpec().getRange(); 1801 NewVD->setInvalidDecl(); 1802 } 1803 1804 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 1805 1806 // If this is a locally-scoped extern C variable, update the map of 1807 // such variables. 1808 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1809 !NewVD->isInvalidDecl()) 1810 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1811 1812 return NewVD; 1813} 1814 1815/// \brief Perform semantic checking on a newly-created variable 1816/// declaration. 1817/// 1818/// This routine performs all of the type-checking required for a 1819/// variable declaration once it has been build. It is used both to 1820/// check variables after they have been parsed and their declarators 1821/// have been translated into a declaration, and to check 1822/// 1823/// Sets NewVD->isInvalidDecl() if an error was encountered. 1824void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1825 bool &Redeclaration) { 1826 // If the decl is already known invalid, don't check it. 1827 if (NewVD->isInvalidDecl()) 1828 return; 1829 1830 QualType T = NewVD->getType(); 1831 1832 if (T->isObjCInterfaceType()) { 1833 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1834 return NewVD->setInvalidDecl(); 1835 } 1836 1837 // The variable can not have an abstract class type. 1838 if (RequireNonAbstractType(NewVD->getLocation(), T, 1839 diag::err_abstract_type_in_decl, 1840 AbstractVariableType)) 1841 return NewVD->setInvalidDecl(); 1842 1843 // Emit an error if an address space was applied to decl with local storage. 1844 // This includes arrays of objects with address space qualifiers, but not 1845 // automatic variables that point to other address spaces. 1846 // ISO/IEC TR 18037 S5.1.2 1847 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1848 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1849 return NewVD->setInvalidDecl(); 1850 } 1851 1852 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1853 && !NewVD->hasAttr<BlocksAttr>()) 1854 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1855 1856 bool isVM = T->isVariablyModifiedType(); 1857 if (isVM || NewVD->hasAttr<CleanupAttr>()) 1858 CurFunctionNeedsScopeChecking = true; 1859 1860 if ((isVM && NewVD->hasLinkage()) || 1861 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 1862 bool SizeIsNegative; 1863 QualType FixedTy = 1864 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1865 1866 if (FixedTy.isNull() && T->isVariableArrayType()) { 1867 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1868 // FIXME: This won't give the correct result for 1869 // int a[10][n]; 1870 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1871 1872 if (NewVD->isFileVarDecl()) 1873 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1874 << SizeRange; 1875 else if (NewVD->getStorageClass() == VarDecl::Static) 1876 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1877 << SizeRange; 1878 else 1879 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1880 << SizeRange; 1881 return NewVD->setInvalidDecl(); 1882 } 1883 1884 if (FixedTy.isNull()) { 1885 if (NewVD->isFileVarDecl()) 1886 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1887 else 1888 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1889 return NewVD->setInvalidDecl(); 1890 } 1891 1892 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1893 NewVD->setType(FixedTy); 1894 } 1895 1896 if (!PrevDecl && NewVD->isExternC(Context)) { 1897 // Since we did not find anything by this name and we're declaring 1898 // an extern "C" variable, look for a non-visible extern "C" 1899 // declaration with the same name. 1900 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1901 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1902 if (Pos != LocallyScopedExternalDecls.end()) 1903 PrevDecl = Pos->second; 1904 } 1905 1906 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 1907 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1908 << T; 1909 return NewVD->setInvalidDecl(); 1910 } 1911 1912 if (PrevDecl) { 1913 Redeclaration = true; 1914 MergeVarDecl(NewVD, PrevDecl); 1915 } 1916} 1917 1918NamedDecl* 1919Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1920 QualType R, NamedDecl* PrevDecl, 1921 bool IsFunctionDefinition, bool &Redeclaration) { 1922 assert(R.getTypePtr()->isFunctionType()); 1923 1924 DeclarationName Name = GetNameForDeclarator(D); 1925 FunctionDecl::StorageClass SC = FunctionDecl::None; 1926 switch (D.getDeclSpec().getStorageClassSpec()) { 1927 default: assert(0 && "Unknown storage class!"); 1928 case DeclSpec::SCS_auto: 1929 case DeclSpec::SCS_register: 1930 case DeclSpec::SCS_mutable: 1931 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1932 diag::err_typecheck_sclass_func); 1933 D.setInvalidType(); 1934 break; 1935 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1936 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1937 case DeclSpec::SCS_static: { 1938 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1939 // C99 6.7.1p5: 1940 // The declaration of an identifier for a function that has 1941 // block scope shall have no explicit storage-class specifier 1942 // other than extern 1943 // See also (C++ [dcl.stc]p4). 1944 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1945 diag::err_static_block_func); 1946 SC = FunctionDecl::None; 1947 } else 1948 SC = FunctionDecl::Static; 1949 break; 1950 } 1951 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1952 } 1953 1954 if (D.getDeclSpec().isThreadSpecified()) 1955 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 1956 1957 bool isInline = D.getDeclSpec().isInlineSpecified(); 1958 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1959 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1960 1961 // Check that the return type is not an abstract class type. 1962 // For record types, this is done by the AbstractClassUsageDiagnoser once 1963 // the class has been completely parsed. 1964 if (!DC->isRecord() && 1965 RequireNonAbstractType(D.getIdentifierLoc(), 1966 R->getAsFunctionType()->getResultType(), 1967 diag::err_abstract_type_in_decl, 1968 AbstractReturnType)) 1969 D.setInvalidType(); 1970 1971 // Do not allow returning a objc interface by-value. 1972 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1973 Diag(D.getIdentifierLoc(), 1974 diag::err_object_cannot_be_passed_returned_by_value) << 0 1975 << R->getAsFunctionType()->getResultType(); 1976 D.setInvalidType(); 1977 } 1978 1979 bool isVirtualOkay = false; 1980 FunctionDecl *NewFD; 1981 if (D.getKind() == Declarator::DK_Constructor) { 1982 // This is a C++ constructor declaration. 1983 assert(DC->isRecord() && 1984 "Constructors can only be declared in a member context"); 1985 1986 R = CheckConstructorDeclarator(D, R, SC); 1987 1988 // Create the new declaration 1989 NewFD = CXXConstructorDecl::Create(Context, 1990 cast<CXXRecordDecl>(DC), 1991 D.getIdentifierLoc(), Name, R, 1992 isExplicit, isInline, 1993 /*isImplicitlyDeclared=*/false); 1994 } else if (D.getKind() == Declarator::DK_Destructor) { 1995 // This is a C++ destructor declaration. 1996 if (DC->isRecord()) { 1997 R = CheckDestructorDeclarator(D, SC); 1998 1999 NewFD = CXXDestructorDecl::Create(Context, 2000 cast<CXXRecordDecl>(DC), 2001 D.getIdentifierLoc(), Name, R, 2002 isInline, 2003 /*isImplicitlyDeclared=*/false); 2004 2005 isVirtualOkay = true; 2006 } else { 2007 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2008 2009 // Create a FunctionDecl to satisfy the function definition parsing 2010 // code path. 2011 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2012 Name, R, SC, isInline, 2013 /*hasPrototype=*/true, 2014 // FIXME: Move to DeclGroup... 2015 D.getDeclSpec().getSourceRange().getBegin()); 2016 D.setInvalidType(); 2017 } 2018 } else if (D.getKind() == Declarator::DK_Conversion) { 2019 if (!DC->isRecord()) { 2020 Diag(D.getIdentifierLoc(), 2021 diag::err_conv_function_not_member); 2022 return 0; 2023 } 2024 2025 CheckConversionDeclarator(D, R, SC); 2026 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2027 D.getIdentifierLoc(), Name, R, 2028 isInline, isExplicit); 2029 2030 isVirtualOkay = true; 2031 } else if (DC->isRecord()) { 2032 // This is a C++ method declaration. 2033 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2034 D.getIdentifierLoc(), Name, R, 2035 (SC == FunctionDecl::Static), isInline); 2036 2037 isVirtualOkay = (SC != FunctionDecl::Static); 2038 } else { 2039 // Determine whether the function was written with a 2040 // prototype. This true when: 2041 // - we're in C++ (where every function has a prototype), 2042 // - there is a prototype in the declarator, or 2043 // - the type R of the function is some kind of typedef or other reference 2044 // to a type name (which eventually refers to a function type). 2045 bool HasPrototype = 2046 getLangOptions().CPlusPlus || 2047 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2048 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2049 2050 NewFD = FunctionDecl::Create(Context, DC, 2051 D.getIdentifierLoc(), 2052 Name, R, SC, isInline, HasPrototype, 2053 // FIXME: Move to DeclGroup... 2054 D.getDeclSpec().getSourceRange().getBegin()); 2055 } 2056 2057 if (D.isInvalidType()) 2058 NewFD->setInvalidDecl(); 2059 2060 // Set the lexical context. If the declarator has a C++ 2061 // scope specifier, the lexical context will be different 2062 // from the semantic context. 2063 NewFD->setLexicalDeclContext(CurContext); 2064 2065 // C++ [dcl.fct.spec]p5: 2066 // The virtual specifier shall only be used in declarations of 2067 // nonstatic class member functions that appear within a 2068 // member-specification of a class declaration; see 10.3. 2069 // 2070 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2071 // function is also virtual if it overrides an already virtual 2072 // function. This is important to do here because it's part of the 2073 // declaration. 2074 if (isVirtual && !NewFD->isInvalidDecl()) { 2075 if (!isVirtualOkay) { 2076 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2077 diag::err_virtual_non_function); 2078 } else if (!CurContext->isRecord()) { 2079 // 'virtual' was specified outside of the class. 2080 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2081 << CodeModificationHint::CreateRemoval( 2082 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2083 } else { 2084 // Okay: Add virtual to the method. 2085 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2086 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2087 CurClass->setAggregate(false); 2088 CurClass->setPOD(false); 2089 CurClass->setPolymorphic(true); 2090 CurClass->setHasTrivialConstructor(false); 2091 } 2092 } 2093 2094 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2095 !CurContext->isRecord()) { 2096 // C++ [class.static]p1: 2097 // A data or function member of a class may be declared static 2098 // in a class definition, in which case it is a static member of 2099 // the class. 2100 2101 // Complain about the 'static' specifier if it's on an out-of-line 2102 // member function definition. 2103 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2104 diag::err_static_out_of_line) 2105 << CodeModificationHint::CreateRemoval( 2106 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2107 } 2108 2109 // Handle GNU asm-label extension (encoded as an attribute). 2110 if (Expr *E = (Expr*) D.getAsmLabel()) { 2111 // The parser guarantees this is a string. 2112 StringLiteral *SE = cast<StringLiteral>(E); 2113 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2114 SE->getByteLength()))); 2115 } 2116 2117 // Copy the parameter declarations from the declarator D to the function 2118 // declaration NewFD, if they are available. First scavenge them into Params. 2119 llvm::SmallVector<ParmVarDecl*, 16> Params; 2120 if (D.getNumTypeObjects() > 0) { 2121 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2122 2123 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2124 // function that takes no arguments, not a function that takes a 2125 // single void argument. 2126 // We let through "const void" here because Sema::GetTypeForDeclarator 2127 // already checks for that case. 2128 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2129 FTI.ArgInfo[0].Param && 2130 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2131 // Empty arg list, don't push any params. 2132 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2133 2134 // In C++, the empty parameter-type-list must be spelled "void"; a 2135 // typedef of void is not permitted. 2136 if (getLangOptions().CPlusPlus && 2137 Param->getType().getUnqualifiedType() != Context.VoidTy) 2138 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2139 // FIXME: Leaks decl? 2140 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2141 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2142 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2143 } 2144 2145 } else if (const FunctionProtoType *FT = R->getAsFunctionProtoType()) { 2146 // When we're declaring a function with a typedef, typeof, etc as in the 2147 // following example, we'll need to synthesize (unnamed) 2148 // parameters for use in the declaration. 2149 // 2150 // @code 2151 // typedef void fn(int); 2152 // fn f; 2153 // @endcode 2154 2155 // Synthesize a parameter for each argument type. 2156 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2157 AE = FT->arg_type_end(); AI != AE; ++AI) { 2158 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2159 SourceLocation(), 0, 2160 *AI, VarDecl::None, 0); 2161 Param->setImplicit(); 2162 Params.push_back(Param); 2163 } 2164 } else { 2165 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2166 "Should not need args for typedef of non-prototype fn"); 2167 } 2168 // Finally, we know we have the right number of parameters, install them. 2169 NewFD->setParams(Context, &Params[0], Params.size()); 2170 2171 2172 2173 // If name lookup finds a previous declaration that is not in the 2174 // same scope as the new declaration, this may still be an 2175 // acceptable redeclaration. 2176 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2177 !(NewFD->hasLinkage() && 2178 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2179 PrevDecl = 0; 2180 2181 // Perform semantic checking on the function declaration. 2182 bool OverloadableAttrRequired = false; // FIXME: HACK! 2183 CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2184 /*FIXME:*/OverloadableAttrRequired); 2185 2186 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2187 // An out-of-line member function declaration must also be a 2188 // definition (C++ [dcl.meaning]p1). 2189 if (!IsFunctionDefinition) { 2190 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2191 << D.getCXXScopeSpec().getRange(); 2192 NewFD->setInvalidDecl(); 2193 } else if (!Redeclaration) { 2194 // The user tried to provide an out-of-line definition for a 2195 // function that is a member of a class or namespace, but there 2196 // was no such member function declared (C++ [class.mfct]p2, 2197 // C++ [namespace.memdef]p2). For example: 2198 // 2199 // class X { 2200 // void f() const; 2201 // }; 2202 // 2203 // void X::f() { } // ill-formed 2204 // 2205 // Complain about this problem, and attempt to suggest close 2206 // matches (e.g., those that differ only in cv-qualifiers and 2207 // whether the parameter types are references). 2208 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2209 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2210 NewFD->setInvalidDecl(); 2211 2212 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2213 true); 2214 assert(!Prev.isAmbiguous() && 2215 "Cannot have an ambiguity in previous-declaration lookup"); 2216 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2217 Func != FuncEnd; ++Func) { 2218 if (isa<FunctionDecl>(*Func) && 2219 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2220 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2221 } 2222 2223 PrevDecl = 0; 2224 } 2225 } 2226 2227 // Handle attributes. We need to have merged decls when handling attributes 2228 // (for example to check for conflicts, etc). 2229 // FIXME: This needs to happen before we merge declarations. Then, 2230 // let attribute merging cope with attribute conflicts. 2231 ProcessDeclAttributes(NewFD, D); 2232 AddKnownFunctionAttributes(NewFD); 2233 2234 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2235 // If a function name is overloadable in C, then every function 2236 // with that name must be marked "overloadable". 2237 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2238 << Redeclaration << NewFD; 2239 if (PrevDecl) 2240 Diag(PrevDecl->getLocation(), 2241 diag::note_attribute_overloadable_prev_overload); 2242 NewFD->addAttr(::new (Context) OverloadableAttr()); 2243 } 2244 2245 // If this is a locally-scoped extern C function, update the 2246 // map of such names. 2247 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2248 && !NewFD->isInvalidDecl()) 2249 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2250 2251 return NewFD; 2252} 2253 2254/// \brief Perform semantic checking of a new function declaration. 2255/// 2256/// Performs semantic analysis of the new function declaration 2257/// NewFD. This routine performs all semantic checking that does not 2258/// require the actual declarator involved in the declaration, and is 2259/// used both for the declaration of functions as they are parsed 2260/// (called via ActOnDeclarator) and for the declaration of functions 2261/// that have been instantiated via C++ template instantiation (called 2262/// via InstantiateDecl). 2263/// 2264/// This sets NewFD->isInvalidDecl() to true if there was an error. 2265void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2266 bool &Redeclaration, 2267 bool &OverloadableAttrRequired) { 2268 // If NewFD is already known erroneous, don't do any of this checking. 2269 if (NewFD->isInvalidDecl()) 2270 return; 2271 2272 // Semantic checking for this function declaration (in isolation). 2273 if (getLangOptions().CPlusPlus) { 2274 // C++-specific checks. 2275 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 2276 CheckConstructor(Constructor); 2277 } else if (isa<CXXDestructorDecl>(NewFD)) { 2278 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2279 Record->setUserDeclaredDestructor(true); 2280 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2281 // user-defined destructor. 2282 Record->setPOD(false); 2283 2284 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 2285 // declared destructor. 2286 Record->setHasTrivialDestructor(false); 2287 } else if (CXXConversionDecl *Conversion 2288 = dyn_cast<CXXConversionDecl>(NewFD)) 2289 ActOnConversionDeclarator(Conversion); 2290 2291 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2292 if (NewFD->isOverloadedOperator() && 2293 CheckOverloadedOperatorDeclaration(NewFD)) 2294 return NewFD->setInvalidDecl(); 2295 } 2296 2297 // C99 6.7.4p6: 2298 // [... ] For a function with external linkage, the following 2299 // restrictions apply: [...] If all of the file scope declarations 2300 // for a function in a translation unit include the inline 2301 // function specifier without extern, then the definition in that 2302 // translation unit is an inline definition. An inline definition 2303 // does not provide an external definition for the function, and 2304 // does not forbid an external definition in another translation 2305 // unit. 2306 // 2307 // Here we determine whether this function, in isolation, would be a 2308 // C99 inline definition. MergeCompatibleFunctionDecls looks at 2309 // previous declarations. 2310 if (NewFD->isInline() && getLangOptions().C99 && 2311 NewFD->getStorageClass() == FunctionDecl::None && 2312 NewFD->getDeclContext()->getLookupContext()->isTranslationUnit()) 2313 NewFD->setC99InlineDefinition(true); 2314 2315 // Check for a previous declaration of this name. 2316 if (!PrevDecl && NewFD->isExternC(Context)) { 2317 // Since we did not find anything by this name and we're declaring 2318 // an extern "C" function, look for a non-visible extern "C" 2319 // declaration with the same name. 2320 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2321 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2322 if (Pos != LocallyScopedExternalDecls.end()) 2323 PrevDecl = Pos->second; 2324 } 2325 2326 // Merge or overload the declaration with an existing declaration of 2327 // the same name, if appropriate. 2328 if (PrevDecl) { 2329 // Determine whether NewFD is an overload of PrevDecl or 2330 // a declaration that requires merging. If it's an overload, 2331 // there's no more work to do here; we'll just add the new 2332 // function to the scope. 2333 OverloadedFunctionDecl::function_iterator MatchedDecl; 2334 2335 if (!getLangOptions().CPlusPlus && 2336 AllowOverloadingOfFunction(PrevDecl, Context)) { 2337 OverloadableAttrRequired = true; 2338 2339 // Functions marked "overloadable" must have a prototype (that 2340 // we can't get through declaration merging). 2341 if (!NewFD->getType()->getAsFunctionProtoType()) { 2342 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2343 << NewFD; 2344 Redeclaration = true; 2345 2346 // Turn this into a variadic function with no parameters. 2347 QualType R = Context.getFunctionType( 2348 NewFD->getType()->getAsFunctionType()->getResultType(), 2349 0, 0, true, 0); 2350 NewFD->setType(R); 2351 return NewFD->setInvalidDecl(); 2352 } 2353 } 2354 2355 if (PrevDecl && 2356 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2357 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2358 Redeclaration = true; 2359 Decl *OldDecl = PrevDecl; 2360 2361 // If PrevDecl was an overloaded function, extract the 2362 // FunctionDecl that matched. 2363 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2364 OldDecl = *MatchedDecl; 2365 2366 // NewFD and OldDecl represent declarations that need to be 2367 // merged. 2368 if (MergeFunctionDecl(NewFD, OldDecl)) 2369 return NewFD->setInvalidDecl(); 2370 2371 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2372 } 2373 } 2374 2375 // In C++, check default arguments now that we have merged decls. Unless 2376 // the lexical context is the class, because in this case this is done 2377 // during delayed parsing anyway. 2378 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) 2379 CheckCXXDefaultArguments(NewFD); 2380} 2381 2382bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2383 // FIXME: Need strict checking. In C89, we need to check for 2384 // any assignment, increment, decrement, function-calls, or 2385 // commas outside of a sizeof. In C99, it's the same list, 2386 // except that the aforementioned are allowed in unevaluated 2387 // expressions. Everything else falls under the 2388 // "may accept other forms of constant expressions" exception. 2389 // (We never end up here for C++, so the constant expression 2390 // rules there don't matter.) 2391 if (Init->isConstantInitializer(Context)) 2392 return false; 2393 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2394 << Init->getSourceRange(); 2395 return true; 2396} 2397 2398void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2399 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2400} 2401 2402/// AddInitializerToDecl - Adds the initializer Init to the 2403/// declaration dcl. If DirectInit is true, this is C++ direct 2404/// initialization rather than copy initialization. 2405void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2406 Decl *RealDecl = dcl.getAs<Decl>(); 2407 // If there is no declaration, there was an error parsing it. Just ignore 2408 // the initializer. 2409 if (RealDecl == 0) 2410 return; 2411 2412 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2413 // With declarators parsed the way they are, the parser cannot 2414 // distinguish between a normal initializer and a pure-specifier. 2415 // Thus this grotesque test. 2416 IntegerLiteral *IL; 2417 Expr *Init = static_cast<Expr *>(init.get()); 2418 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2419 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2420 if (Method->isVirtual()) { 2421 Method->setPure(); 2422 2423 // A class is abstract if at least one function is pure virtual. 2424 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2425 } else if (!Method->isInvalidDecl()) { 2426 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2427 << Method->getDeclName() << Init->getSourceRange(); 2428 Method->setInvalidDecl(); 2429 } 2430 } else { 2431 Diag(Method->getLocation(), diag::err_member_function_initialization) 2432 << Method->getDeclName() << Init->getSourceRange(); 2433 Method->setInvalidDecl(); 2434 } 2435 return; 2436 } 2437 2438 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2439 if (!VDecl) { 2440 if (getLangOptions().CPlusPlus && 2441 RealDecl->getLexicalDeclContext()->isRecord() && 2442 isa<NamedDecl>(RealDecl)) 2443 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2444 << cast<NamedDecl>(RealDecl)->getDeclName(); 2445 else 2446 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2447 RealDecl->setInvalidDecl(); 2448 return; 2449 } 2450 2451 if (!VDecl->getType()->isArrayType() && 2452 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2453 diag::err_typecheck_decl_incomplete_type)) { 2454 RealDecl->setInvalidDecl(); 2455 return; 2456 } 2457 2458 const VarDecl *Def = 0; 2459 if (VDecl->getDefinition(Def)) { 2460 Diag(VDecl->getLocation(), diag::err_redefinition) 2461 << VDecl->getDeclName(); 2462 Diag(Def->getLocation(), diag::note_previous_definition); 2463 VDecl->setInvalidDecl(); 2464 return; 2465 } 2466 2467 // Take ownership of the expression, now that we're sure we have somewhere 2468 // to put it. 2469 Expr *Init = static_cast<Expr *>(init.release()); 2470 assert(Init && "missing initializer"); 2471 2472 // Get the decls type and save a reference for later, since 2473 // CheckInitializerTypes may change it. 2474 QualType DclT = VDecl->getType(), SavT = DclT; 2475 if (VDecl->isBlockVarDecl()) { 2476 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2477 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2478 VDecl->setInvalidDecl(); 2479 } else if (!VDecl->isInvalidDecl()) { 2480 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2481 VDecl->getDeclName(), DirectInit)) 2482 VDecl->setInvalidDecl(); 2483 2484 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2485 // Don't check invalid declarations to avoid emitting useless diagnostics. 2486 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2487 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2488 CheckForConstantInitializer(Init, DclT); 2489 } 2490 } 2491 } else if (VDecl->isStaticDataMember() && 2492 VDecl->getLexicalDeclContext()->isRecord()) { 2493 // This is an in-class initialization for a static data member, e.g., 2494 // 2495 // struct S { 2496 // static const int value = 17; 2497 // }; 2498 2499 // Attach the initializer 2500 VDecl->setInit(Init); 2501 2502 // C++ [class.mem]p4: 2503 // A member-declarator can contain a constant-initializer only 2504 // if it declares a static member (9.4) of const integral or 2505 // const enumeration type, see 9.4.2. 2506 QualType T = VDecl->getType(); 2507 if (!T->isDependentType() && 2508 (!Context.getCanonicalType(T).isConstQualified() || 2509 !T->isIntegralType())) { 2510 Diag(VDecl->getLocation(), diag::err_member_initialization) 2511 << VDecl->getDeclName() << Init->getSourceRange(); 2512 VDecl->setInvalidDecl(); 2513 } else { 2514 // C++ [class.static.data]p4: 2515 // If a static data member is of const integral or const 2516 // enumeration type, its declaration in the class definition 2517 // can specify a constant-initializer which shall be an 2518 // integral constant expression (5.19). 2519 if (!Init->isTypeDependent() && 2520 !Init->getType()->isIntegralType()) { 2521 // We have a non-dependent, non-integral or enumeration type. 2522 Diag(Init->getSourceRange().getBegin(), 2523 diag::err_in_class_initializer_non_integral_type) 2524 << Init->getType() << Init->getSourceRange(); 2525 VDecl->setInvalidDecl(); 2526 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2527 // Check whether the expression is a constant expression. 2528 llvm::APSInt Value; 2529 SourceLocation Loc; 2530 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2531 Diag(Loc, diag::err_in_class_initializer_non_constant) 2532 << Init->getSourceRange(); 2533 VDecl->setInvalidDecl(); 2534 } else if (!VDecl->getType()->isDependentType()) 2535 ImpCastExprToType(Init, VDecl->getType()); 2536 } 2537 } 2538 } else if (VDecl->isFileVarDecl()) { 2539 if (VDecl->getStorageClass() == VarDecl::Extern) 2540 Diag(VDecl->getLocation(), diag::warn_extern_init); 2541 if (!VDecl->isInvalidDecl()) 2542 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2543 VDecl->getDeclName(), DirectInit)) 2544 VDecl->setInvalidDecl(); 2545 2546 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2547 // Don't check invalid declarations to avoid emitting useless diagnostics. 2548 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2549 // C99 6.7.8p4. All file scoped initializers need to be constant. 2550 CheckForConstantInitializer(Init, DclT); 2551 } 2552 } 2553 // If the type changed, it means we had an incomplete type that was 2554 // completed by the initializer. For example: 2555 // int ary[] = { 1, 3, 5 }; 2556 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2557 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2558 VDecl->setType(DclT); 2559 Init->setType(DclT); 2560 } 2561 2562 // Attach the initializer to the decl. 2563 VDecl->setInit(Init); 2564 2565 // If the previous declaration of VDecl was a tentative definition, 2566 // remove it from the set of tentative definitions. 2567 if (VDecl->getPreviousDeclaration() && 2568 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 2569 llvm::DenseMap<DeclarationName, VarDecl *>::iterator Pos 2570 = TentativeDefinitions.find(VDecl->getDeclName()); 2571 assert(Pos != TentativeDefinitions.end() && 2572 "Unrecorded tentative definition?"); 2573 TentativeDefinitions.erase(Pos); 2574 } 2575 2576 return; 2577} 2578 2579void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2580 Decl *RealDecl = dcl.getAs<Decl>(); 2581 2582 // If there is no declaration, there was an error parsing it. Just ignore it. 2583 if (RealDecl == 0) 2584 return; 2585 2586 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2587 QualType Type = Var->getType(); 2588 2589 // Record tentative definitions. 2590 if (Var->isTentativeDefinition(Context)) 2591 TentativeDefinitions[Var->getDeclName()] = Var; 2592 2593 // C++ [dcl.init.ref]p3: 2594 // The initializer can be omitted for a reference only in a 2595 // parameter declaration (8.3.5), in the declaration of a 2596 // function return type, in the declaration of a class member 2597 // within its class declaration (9.2), and where the extern 2598 // specifier is explicitly used. 2599 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2600 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2601 << Var->getDeclName() 2602 << SourceRange(Var->getLocation(), Var->getLocation()); 2603 Var->setInvalidDecl(); 2604 return; 2605 } 2606 2607 // C++ [dcl.init]p9: 2608 // 2609 // If no initializer is specified for an object, and the object 2610 // is of (possibly cv-qualified) non-POD class type (or array 2611 // thereof), the object shall be default-initialized; if the 2612 // object is of const-qualified type, the underlying class type 2613 // shall have a user-declared default constructor. 2614 if (getLangOptions().CPlusPlus) { 2615 QualType InitType = Type; 2616 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2617 InitType = Array->getElementType(); 2618 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2619 CXXRecordDecl *RD = 2620 cast<CXXRecordDecl>(InitType->getAsRecordType()->getDecl()); 2621 CXXConstructorDecl *Constructor = 0; 2622 if (!RequireCompleteType(Var->getLocation(), InitType, 2623 diag::err_invalid_incomplete_type_use)) 2624 Constructor 2625 = PerformInitializationByConstructor(InitType, 0, 0, 2626 Var->getLocation(), 2627 SourceRange(Var->getLocation(), 2628 Var->getLocation()), 2629 Var->getDeclName(), 2630 IK_Default); 2631 if (!Constructor) 2632 Var->setInvalidDecl(); 2633 else if (!RD->hasTrivialConstructor()) 2634 InitializeVarWithConstructor(Var, Constructor, InitType, 0, 0); 2635 } 2636 } 2637 2638#if 0 2639 // FIXME: Temporarily disabled because we are not properly parsing 2640 // linkage specifications on declarations, e.g., 2641 // 2642 // extern "C" const CGPoint CGPointerZero; 2643 // 2644 // C++ [dcl.init]p9: 2645 // 2646 // If no initializer is specified for an object, and the 2647 // object is of (possibly cv-qualified) non-POD class type (or 2648 // array thereof), the object shall be default-initialized; if 2649 // the object is of const-qualified type, the underlying class 2650 // type shall have a user-declared default 2651 // constructor. Otherwise, if no initializer is specified for 2652 // an object, the object and its subobjects, if any, have an 2653 // indeterminate initial value; if the object or any of its 2654 // subobjects are of const-qualified type, the program is 2655 // ill-formed. 2656 // 2657 // This isn't technically an error in C, so we don't diagnose it. 2658 // 2659 // FIXME: Actually perform the POD/user-defined default 2660 // constructor check. 2661 if (getLangOptions().CPlusPlus && 2662 Context.getCanonicalType(Type).isConstQualified() && 2663 !Var->hasExternalStorage()) 2664 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2665 << Var->getName() 2666 << SourceRange(Var->getLocation(), Var->getLocation()); 2667#endif 2668 } 2669} 2670 2671Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2672 unsigned NumDecls) { 2673 llvm::SmallVector<Decl*, 8> Decls; 2674 2675 for (unsigned i = 0; i != NumDecls; ++i) 2676 if (Decl *D = Group[i].getAs<Decl>()) 2677 Decls.push_back(D); 2678 2679 // Perform semantic analysis that depends on having fully processed both 2680 // the declarator and initializer. 2681 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2682 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2683 if (!IDecl) 2684 continue; 2685 QualType T = IDecl->getType(); 2686 2687 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2688 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2689 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2690 if (!IDecl->isInvalidDecl() && 2691 RequireCompleteType(IDecl->getLocation(), T, 2692 diag::err_typecheck_decl_incomplete_type)) 2693 IDecl->setInvalidDecl(); 2694 } 2695 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2696 // object that has file scope without an initializer, and without a 2697 // storage-class specifier or with the storage-class specifier "static", 2698 // constitutes a tentative definition. Note: A tentative definition with 2699 // external linkage is valid (C99 6.2.2p5). 2700 if (IDecl->isTentativeDefinition(Context)) { 2701 QualType CheckType = T; 2702 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2703 2704 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2705 if (ArrayT) { 2706 CheckType = ArrayT->getElementType(); 2707 DiagID = diag::err_illegal_decl_array_incomplete_type; 2708 } 2709 2710 if (IDecl->isInvalidDecl()) { 2711 // Do nothing with invalid declarations 2712 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2713 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2714 // C99 6.9.2p3: If the declaration of an identifier for an object is 2715 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2716 // declared type shall not be an incomplete type. 2717 IDecl->setInvalidDecl(); 2718 } 2719 } 2720 } 2721 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2722 &Decls[0], Decls.size())); 2723} 2724 2725 2726/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2727/// to introduce parameters into function prototype scope. 2728Sema::DeclPtrTy 2729Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2730 const DeclSpec &DS = D.getDeclSpec(); 2731 2732 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2733 VarDecl::StorageClass StorageClass = VarDecl::None; 2734 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2735 StorageClass = VarDecl::Register; 2736 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2737 Diag(DS.getStorageClassSpecLoc(), 2738 diag::err_invalid_storage_class_in_func_decl); 2739 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2740 } 2741 2742 if (D.getDeclSpec().isThreadSpecified()) 2743 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2744 2745 DiagnoseFunctionSpecifiers(D); 2746 2747 // Check that there are no default arguments inside the type of this 2748 // parameter (C++ only). 2749 if (getLangOptions().CPlusPlus) 2750 CheckExtraCXXDefaultArguments(D); 2751 2752 QualType parmDeclType = GetTypeForDeclarator(D, S); 2753 2754 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2755 // Can this happen for params? We already checked that they don't conflict 2756 // among each other. Here they can only shadow globals, which is ok. 2757 IdentifierInfo *II = D.getIdentifier(); 2758 if (II) { 2759 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2760 if (PrevDecl->isTemplateParameter()) { 2761 // Maybe we will complain about the shadowed template parameter. 2762 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2763 // Just pretend that we didn't see the previous declaration. 2764 PrevDecl = 0; 2765 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2766 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2767 2768 // Recover by removing the name 2769 II = 0; 2770 D.SetIdentifier(0, D.getIdentifierLoc()); 2771 } 2772 } 2773 } 2774 2775 // Parameters can not be abstract class types. 2776 // For record types, this is done by the AbstractClassUsageDiagnoser once 2777 // the class has been completely parsed. 2778 if (!CurContext->isRecord() && 2779 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2780 diag::err_abstract_type_in_decl, 2781 AbstractParamType)) 2782 D.setInvalidType(true); 2783 2784 QualType T = adjustParameterType(parmDeclType); 2785 2786 ParmVarDecl *New; 2787 if (T == parmDeclType) // parameter type did not need adjustment 2788 New = ParmVarDecl::Create(Context, CurContext, 2789 D.getIdentifierLoc(), II, 2790 parmDeclType, StorageClass, 2791 0); 2792 else // keep track of both the adjusted and unadjusted types 2793 New = OriginalParmVarDecl::Create(Context, CurContext, 2794 D.getIdentifierLoc(), II, T, 2795 parmDeclType, StorageClass, 0); 2796 2797 if (D.isInvalidType()) 2798 New->setInvalidDecl(); 2799 2800 // Parameter declarators cannot be interface types. All ObjC objects are 2801 // passed by reference. 2802 if (T->isObjCInterfaceType()) { 2803 Diag(D.getIdentifierLoc(), 2804 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2805 New->setInvalidDecl(); 2806 } 2807 2808 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2809 if (D.getCXXScopeSpec().isSet()) { 2810 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2811 << D.getCXXScopeSpec().getRange(); 2812 New->setInvalidDecl(); 2813 } 2814 2815 // Add the parameter declaration into this scope. 2816 S->AddDecl(DeclPtrTy::make(New)); 2817 if (II) 2818 IdResolver.AddDecl(New); 2819 2820 ProcessDeclAttributes(New, D); 2821 return DeclPtrTy::make(New); 2822} 2823 2824void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2825 SourceLocation LocAfterDecls) { 2826 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2827 "Not a function declarator!"); 2828 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2829 2830 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2831 // for a K&R function. 2832 if (!FTI.hasPrototype) { 2833 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2834 --i; 2835 if (FTI.ArgInfo[i].Param == 0) { 2836 std::string Code = " int "; 2837 Code += FTI.ArgInfo[i].Ident->getName(); 2838 Code += ";\n"; 2839 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2840 << FTI.ArgInfo[i].Ident 2841 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2842 2843 // Implicitly declare the argument as type 'int' for lack of a better 2844 // type. 2845 DeclSpec DS; 2846 const char* PrevSpec; // unused 2847 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2848 PrevSpec); 2849 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2850 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2851 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2852 } 2853 } 2854 } 2855} 2856 2857Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2858 Declarator &D) { 2859 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2860 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2861 "Not a function declarator!"); 2862 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2863 2864 if (FTI.hasPrototype) { 2865 // FIXME: Diagnose arguments without names in C. 2866 } 2867 2868 Scope *ParentScope = FnBodyScope->getParent(); 2869 2870 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2871 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2872} 2873 2874Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2875 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2876 2877 CurFunctionNeedsScopeChecking = false; 2878 2879 // See if this is a redefinition. 2880 const FunctionDecl *Definition; 2881 if (FD->getBody(Context, Definition)) { 2882 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2883 Diag(Definition->getLocation(), diag::note_previous_definition); 2884 } 2885 2886 // Builtin functions cannot be defined. 2887 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2888 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2889 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2890 FD->setInvalidDecl(); 2891 } 2892 } 2893 2894 // The return type of a function definition must be complete 2895 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2896 QualType ResultType = FD->getResultType(); 2897 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2898 RequireCompleteType(FD->getLocation(), ResultType, 2899 diag::err_func_def_incomplete_result)) 2900 FD->setInvalidDecl(); 2901 2902 // GNU warning -Wmissing-prototypes: 2903 // Warn if a global function is defined without a previous 2904 // prototype declaration. This warning is issued even if the 2905 // definition itself provides a prototype. The aim is to detect 2906 // global functions that fail to be declared in header files. 2907 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2908 !FD->isMain()) { 2909 bool MissingPrototype = true; 2910 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2911 Prev; Prev = Prev->getPreviousDeclaration()) { 2912 // Ignore any declarations that occur in function or method 2913 // scope, because they aren't visible from the header. 2914 if (Prev->getDeclContext()->isFunctionOrMethod()) 2915 continue; 2916 2917 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2918 break; 2919 } 2920 2921 if (MissingPrototype) 2922 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2923 } 2924 2925 PushDeclContext(FnBodyScope, FD); 2926 2927 // Check the validity of our function parameters 2928 CheckParmsForFunctionDef(FD); 2929 2930 // Introduce our parameters into the function scope 2931 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2932 ParmVarDecl *Param = FD->getParamDecl(p); 2933 Param->setOwningFunction(FD); 2934 2935 // If this has an identifier, add it to the scope stack. 2936 if (Param->getIdentifier()) 2937 PushOnScopeChains(Param, FnBodyScope); 2938 } 2939 2940 // Checking attributes of current function definition 2941 // dllimport attribute. 2942 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2943 // dllimport attribute cannot be applied to definition. 2944 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2945 Diag(FD->getLocation(), 2946 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2947 << "dllimport"; 2948 FD->setInvalidDecl(); 2949 return DeclPtrTy::make(FD); 2950 } else { 2951 // If a symbol previously declared dllimport is later defined, the 2952 // attribute is ignored in subsequent references, and a warning is 2953 // emitted. 2954 Diag(FD->getLocation(), 2955 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2956 << FD->getNameAsCString() << "dllimport"; 2957 } 2958 } 2959 return DeclPtrTy::make(FD); 2960} 2961 2962 2963Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 2964 Decl *dcl = D.getAs<Decl>(); 2965 Stmt *Body = BodyArg.takeAs<Stmt>(); 2966 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2967 FD->setBody(Body); 2968 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2969 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2970 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2971 MD->setBody(Body); 2972 } else { 2973 Body->Destroy(Context); 2974 return DeclPtrTy(); 2975 } 2976 PopDeclContext(); 2977 // Verify and clean out per-function state. 2978 2979 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 2980 2981 // Check goto/label use. 2982 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2983 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 2984 LabelStmt *L = I->second; 2985 2986 // Verify that we have no forward references left. If so, there was a goto 2987 // or address of a label taken, but no definition of it. Label fwd 2988 // definitions are indicated with a null substmt. 2989 if (L->getSubStmt() != 0) 2990 continue; 2991 2992 // Emit error. 2993 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2994 2995 // At this point, we have gotos that use the bogus label. Stitch it into 2996 // the function body so that they aren't leaked and that the AST is well 2997 // formed. 2998 if (Body == 0) { 2999 // The whole function wasn't parsed correctly, just delete this. 3000 L->Destroy(Context); 3001 continue; 3002 } 3003 3004 // Otherwise, the body is valid: we want to stitch the label decl into the 3005 // function somewhere so that it is properly owned and so that the goto 3006 // has a valid target. Do this by creating a new compound stmt with the 3007 // label in it. 3008 3009 // Give the label a sub-statement. 3010 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3011 3012 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 3013 cast<CXXTryStmt>(Body)->getTryBlock() : 3014 cast<CompoundStmt>(Body); 3015 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 3016 Elements.push_back(L); 3017 Compound->setStmts(Context, &Elements[0], Elements.size()); 3018 } 3019 FunctionLabelMap.clear(); 3020 3021 if (!Body) return D; 3022 3023 // Verify that that gotos and switch cases don't jump into scopes illegally. 3024 if (CurFunctionNeedsScopeChecking) 3025 DiagnoseInvalidJumps(Body); 3026 3027 // C++ constructors that have function-try-blocks can't have return statements 3028 // in the handlers of that block. (C++ [except.handle]p14) Verify this. 3029 if (isa<CXXConstructorDecl>(dcl) && isa<CXXTryStmt>(Body)) 3030 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 3031 3032 return D; 3033} 3034 3035/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3036/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3037NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3038 IdentifierInfo &II, Scope *S) { 3039 // Before we produce a declaration for an implicitly defined 3040 // function, see whether there was a locally-scoped declaration of 3041 // this name as a function or variable. If so, use that 3042 // (non-visible) declaration, and complain about it. 3043 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3044 = LocallyScopedExternalDecls.find(&II); 3045 if (Pos != LocallyScopedExternalDecls.end()) { 3046 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3047 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3048 return Pos->second; 3049 } 3050 3051 // Extension in C99. Legal in C90, but warn about it. 3052 if (getLangOptions().C99) 3053 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3054 else 3055 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3056 3057 // FIXME: handle stuff like: 3058 // void foo() { extern float X(); } 3059 // void bar() { X(); } <-- implicit decl for X in another scope. 3060 3061 // Set a Declarator for the implicit definition: int foo(); 3062 const char *Dummy; 3063 DeclSpec DS; 3064 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3065 Error = Error; // Silence warning. 3066 assert(!Error && "Error setting up implicit decl!"); 3067 Declarator D(DS, Declarator::BlockContext); 3068 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3069 0, 0, 0, Loc, D), 3070 SourceLocation()); 3071 D.SetIdentifier(&II, Loc); 3072 3073 // Insert this function into translation-unit scope. 3074 3075 DeclContext *PrevDC = CurContext; 3076 CurContext = Context.getTranslationUnitDecl(); 3077 3078 FunctionDecl *FD = 3079 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3080 FD->setImplicit(); 3081 3082 CurContext = PrevDC; 3083 3084 AddKnownFunctionAttributes(FD); 3085 3086 return FD; 3087} 3088 3089/// \brief Adds any function attributes that we know a priori based on 3090/// the declaration of this function. 3091/// 3092/// These attributes can apply both to implicitly-declared builtins 3093/// (like __builtin___printf_chk) or to library-declared functions 3094/// like NSLog or printf. 3095void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3096 if (FD->isInvalidDecl()) 3097 return; 3098 3099 // If this is a built-in function, map its builtin attributes to 3100 // actual attributes. 3101 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3102 // Handle printf-formatting attributes. 3103 unsigned FormatIdx; 3104 bool HasVAListArg; 3105 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3106 if (!FD->getAttr<FormatAttr>()) 3107 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3108 FormatIdx + 2)); 3109 } 3110 3111 // Mark const if we don't care about errno and that is the only 3112 // thing preventing the function from being const. This allows 3113 // IRgen to use LLVM intrinsics for such functions. 3114 if (!getLangOptions().MathErrno && 3115 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3116 if (!FD->getAttr<ConstAttr>()) 3117 FD->addAttr(::new (Context) ConstAttr()); 3118 } 3119 } 3120 3121 IdentifierInfo *Name = FD->getIdentifier(); 3122 if (!Name) 3123 return; 3124 if ((!getLangOptions().CPlusPlus && 3125 FD->getDeclContext()->isTranslationUnit()) || 3126 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3127 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3128 LinkageSpecDecl::lang_c)) { 3129 // Okay: this could be a libc/libm/Objective-C function we know 3130 // about. 3131 } else 3132 return; 3133 3134 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 3135 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3136 // FIXME: We known better than our headers. 3137 const_cast<FormatAttr *>(Format)->setType("printf"); 3138 } else 3139 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3140 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 3141 if (!FD->getAttr<FormatAttr>()) 3142 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3143 } 3144} 3145 3146TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3147 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3148 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3149 3150 // Scope manipulation handled by caller. 3151 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3152 D.getIdentifierLoc(), 3153 D.getIdentifier(), 3154 T); 3155 3156 if (TagType *TT = dyn_cast<TagType>(T)) { 3157 TagDecl *TD = TT->getDecl(); 3158 3159 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3160 // keep track of the TypedefDecl. 3161 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3162 TD->setTypedefForAnonDecl(NewTD); 3163 } 3164 3165 if (D.isInvalidType()) 3166 NewTD->setInvalidDecl(); 3167 return NewTD; 3168} 3169 3170/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3171/// former case, Name will be non-null. In the later case, Name will be null. 3172/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3173/// reference/declaration/definition of a tag. 3174Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3175 SourceLocation KWLoc, const CXXScopeSpec &SS, 3176 IdentifierInfo *Name, SourceLocation NameLoc, 3177 AttributeList *Attr, AccessSpecifier AS) { 3178 // If this is not a definition, it must have a name. 3179 assert((Name != 0 || TK == TK_Definition) && 3180 "Nameless record must be a definition!"); 3181 3182 TagDecl::TagKind Kind; 3183 switch (TagSpec) { 3184 default: assert(0 && "Unknown tag type!"); 3185 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3186 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3187 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3188 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3189 } 3190 3191 DeclContext *SearchDC = CurContext; 3192 DeclContext *DC = CurContext; 3193 NamedDecl *PrevDecl = 0; 3194 3195 bool Invalid = false; 3196 3197 if (Name && SS.isNotEmpty()) { 3198 // We have a nested-name tag ('struct foo::bar'). 3199 3200 // Check for invalid 'foo::'. 3201 if (SS.isInvalid()) { 3202 Name = 0; 3203 goto CreateNewDecl; 3204 } 3205 3206 // FIXME: RequireCompleteDeclContext(SS)? 3207 DC = computeDeclContext(SS); 3208 SearchDC = DC; 3209 // Look-up name inside 'foo::'. 3210 PrevDecl = dyn_cast_or_null<TagDecl>( 3211 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3212 3213 // A tag 'foo::bar' must already exist. 3214 if (PrevDecl == 0) { 3215 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3216 Name = 0; 3217 goto CreateNewDecl; 3218 } 3219 } else if (Name) { 3220 // If this is a named struct, check to see if there was a previous forward 3221 // declaration or definition. 3222 // FIXME: We're looking into outer scopes here, even when we 3223 // shouldn't be. Doing so can result in ambiguities that we 3224 // shouldn't be diagnosing. 3225 LookupResult R = LookupName(S, Name, LookupTagName, 3226 /*RedeclarationOnly=*/(TK != TK_Reference)); 3227 if (R.isAmbiguous()) { 3228 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3229 // FIXME: This is not best way to recover from case like: 3230 // 3231 // struct S s; 3232 // 3233 // causes needless "incomplete type" error later. 3234 Name = 0; 3235 PrevDecl = 0; 3236 Invalid = true; 3237 } 3238 else 3239 PrevDecl = R; 3240 3241 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3242 // FIXME: This makes sure that we ignore the contexts associated 3243 // with C structs, unions, and enums when looking for a matching 3244 // tag declaration or definition. See the similar lookup tweak 3245 // in Sema::LookupName; is there a better way to deal with this? 3246 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3247 SearchDC = SearchDC->getParent(); 3248 } 3249 } 3250 3251 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3252 // Maybe we will complain about the shadowed template parameter. 3253 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3254 // Just pretend that we didn't see the previous declaration. 3255 PrevDecl = 0; 3256 } 3257 3258 if (PrevDecl) { 3259 // Check whether the previous declaration is usable. 3260 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3261 3262 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3263 // If this is a use of a previous tag, or if the tag is already declared 3264 // in the same scope (so that the definition/declaration completes or 3265 // rementions the tag), reuse the decl. 3266 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3267 // Make sure that this wasn't declared as an enum and now used as a 3268 // struct or something similar. 3269 if (PrevTagDecl->getTagKind() != Kind) { 3270 bool SafeToContinue 3271 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3272 Kind != TagDecl::TK_enum); 3273 if (SafeToContinue) 3274 Diag(KWLoc, diag::err_use_with_wrong_tag) 3275 << Name 3276 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3277 PrevTagDecl->getKindName()); 3278 else 3279 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3280 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3281 3282 if (SafeToContinue) 3283 Kind = PrevTagDecl->getTagKind(); 3284 else { 3285 // Recover by making this an anonymous redefinition. 3286 Name = 0; 3287 PrevDecl = 0; 3288 Invalid = true; 3289 } 3290 } 3291 3292 if (!Invalid) { 3293 // If this is a use, just return the declaration we found. 3294 3295 // FIXME: In the future, return a variant or some other clue 3296 // for the consumer of this Decl to know it doesn't own it. 3297 // For our current ASTs this shouldn't be a problem, but will 3298 // need to be changed with DeclGroups. 3299 if (TK == TK_Reference) 3300 return DeclPtrTy::make(PrevDecl); 3301 3302 // Diagnose attempts to redefine a tag. 3303 if (TK == TK_Definition) { 3304 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3305 Diag(NameLoc, diag::err_redefinition) << Name; 3306 Diag(Def->getLocation(), diag::note_previous_definition); 3307 // If this is a redefinition, recover by making this 3308 // struct be anonymous, which will make any later 3309 // references get the previous definition. 3310 Name = 0; 3311 PrevDecl = 0; 3312 Invalid = true; 3313 } else { 3314 // If the type is currently being defined, complain 3315 // about a nested redefinition. 3316 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3317 if (Tag->isBeingDefined()) { 3318 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3319 Diag(PrevTagDecl->getLocation(), 3320 diag::note_previous_definition); 3321 Name = 0; 3322 PrevDecl = 0; 3323 Invalid = true; 3324 } 3325 } 3326 3327 // Okay, this is definition of a previously declared or referenced 3328 // tag PrevDecl. We're going to create a new Decl for it. 3329 } 3330 } 3331 // If we get here we have (another) forward declaration or we 3332 // have a definition. Just create a new decl. 3333 } else { 3334 // If we get here, this is a definition of a new tag type in a nested 3335 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3336 // new decl/type. We set PrevDecl to NULL so that the entities 3337 // have distinct types. 3338 PrevDecl = 0; 3339 } 3340 // If we get here, we're going to create a new Decl. If PrevDecl 3341 // is non-NULL, it's a definition of the tag declared by 3342 // PrevDecl. If it's NULL, we have a new definition. 3343 } else { 3344 // PrevDecl is a namespace, template, or anything else 3345 // that lives in the IDNS_Tag identifier namespace. 3346 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3347 // The tag name clashes with a namespace name, issue an error and 3348 // recover by making this tag be anonymous. 3349 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3350 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3351 Name = 0; 3352 PrevDecl = 0; 3353 Invalid = true; 3354 } else { 3355 // The existing declaration isn't relevant to us; we're in a 3356 // new scope, so clear out the previous declaration. 3357 PrevDecl = 0; 3358 } 3359 } 3360 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3361 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3362 // C.scope.pdecl]p5: 3363 // -- for an elaborated-type-specifier of the form 3364 // 3365 // class-key identifier 3366 // 3367 // if the elaborated-type-specifier is used in the 3368 // decl-specifier-seq or parameter-declaration-clause of a 3369 // function defined in namespace scope, the identifier is 3370 // declared as a class-name in the namespace that contains 3371 // the declaration; otherwise, except as a friend 3372 // declaration, the identifier is declared in the smallest 3373 // non-class, non-function-prototype scope that contains the 3374 // declaration. 3375 // 3376 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3377 // C structs and unions. 3378 // 3379 // GNU C also supports this behavior as part of its incomplete 3380 // enum types extension, while GNU C++ does not. 3381 // 3382 // Find the context where we'll be declaring the tag. 3383 // FIXME: We would like to maintain the current DeclContext as the 3384 // lexical context, 3385 while (SearchDC->isRecord()) 3386 SearchDC = SearchDC->getParent(); 3387 3388 // Find the scope where we'll be declaring the tag. 3389 while (S->isClassScope() || 3390 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3391 ((S->getFlags() & Scope::DeclScope) == 0) || 3392 (S->getEntity() && 3393 ((DeclContext *)S->getEntity())->isTransparentContext())) 3394 S = S->getParent(); 3395 } 3396 3397CreateNewDecl: 3398 3399 // If there is an identifier, use the location of the identifier as the 3400 // location of the decl, otherwise use the location of the struct/union 3401 // keyword. 3402 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3403 3404 // Otherwise, create a new declaration. If there is a previous 3405 // declaration of the same entity, the two will be linked via 3406 // PrevDecl. 3407 TagDecl *New; 3408 3409 if (Kind == TagDecl::TK_enum) { 3410 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3411 // enum X { A, B, C } D; D should chain to X. 3412 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3413 cast_or_null<EnumDecl>(PrevDecl)); 3414 // If this is an undefined enum, warn. 3415 if (TK != TK_Definition && !Invalid) { 3416 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3417 : diag::ext_forward_ref_enum; 3418 Diag(Loc, DK); 3419 } 3420 } else { 3421 // struct/union/class 3422 3423 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3424 // struct X { int A; } D; D should chain to X. 3425 if (getLangOptions().CPlusPlus) 3426 // FIXME: Look for a way to use RecordDecl for simple structs. 3427 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3428 cast_or_null<CXXRecordDecl>(PrevDecl)); 3429 else 3430 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3431 cast_or_null<RecordDecl>(PrevDecl)); 3432 } 3433 3434 if (Kind != TagDecl::TK_enum) { 3435 // Handle #pragma pack: if the #pragma pack stack has non-default 3436 // alignment, make up a packed attribute for this decl. These 3437 // attributes are checked when the ASTContext lays out the 3438 // structure. 3439 // 3440 // It is important for implementing the correct semantics that this 3441 // happen here (in act on tag decl). The #pragma pack stack is 3442 // maintained as a result of parser callbacks which can occur at 3443 // many points during the parsing of a struct declaration (because 3444 // the #pragma tokens are effectively skipped over during the 3445 // parsing of the struct). 3446 if (unsigned Alignment = getPragmaPackAlignment()) 3447 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3448 } 3449 3450 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3451 // C++ [dcl.typedef]p3: 3452 // [...] Similarly, in a given scope, a class or enumeration 3453 // shall not be declared with the same name as a typedef-name 3454 // that is declared in that scope and refers to a type other 3455 // than the class or enumeration itself. 3456 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3457 TypedefDecl *PrevTypedef = 0; 3458 if (Lookup.getKind() == LookupResult::Found) 3459 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3460 3461 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3462 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3463 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3464 Diag(Loc, diag::err_tag_definition_of_typedef) 3465 << Context.getTypeDeclType(New) 3466 << PrevTypedef->getUnderlyingType(); 3467 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3468 Invalid = true; 3469 } 3470 } 3471 3472 if (Invalid) 3473 New->setInvalidDecl(); 3474 3475 if (Attr) 3476 ProcessDeclAttributeList(New, Attr); 3477 3478 // If we're declaring or defining a tag in function prototype scope 3479 // in C, note that this type can only be used within the function. 3480 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3481 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3482 3483 // Set the lexical context. If the tag has a C++ scope specifier, the 3484 // lexical context will be different from the semantic context. 3485 New->setLexicalDeclContext(CurContext); 3486 3487 // Set the access specifier. 3488 SetMemberAccessSpecifier(New, PrevDecl, AS); 3489 3490 if (TK == TK_Definition) 3491 New->startDefinition(); 3492 3493 // If this has an identifier, add it to the scope stack. 3494 if (Name) { 3495 S = getNonFieldDeclScope(S); 3496 PushOnScopeChains(New, S); 3497 } else { 3498 CurContext->addDecl(Context, New); 3499 } 3500 3501 return DeclPtrTy::make(New); 3502} 3503 3504void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3505 AdjustDeclIfTemplate(TagD); 3506 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3507 3508 // Enter the tag context. 3509 PushDeclContext(S, Tag); 3510 3511 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3512 FieldCollector->StartClass(); 3513 3514 if (Record->getIdentifier()) { 3515 // C++ [class]p2: 3516 // [...] The class-name is also inserted into the scope of the 3517 // class itself; this is known as the injected-class-name. For 3518 // purposes of access checking, the injected-class-name is treated 3519 // as if it were a public member name. 3520 CXXRecordDecl *InjectedClassName 3521 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3522 CurContext, Record->getLocation(), 3523 Record->getIdentifier(), Record); 3524 InjectedClassName->setImplicit(); 3525 InjectedClassName->setAccess(AS_public); 3526 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3527 InjectedClassName->setDescribedClassTemplate(Template); 3528 PushOnScopeChains(InjectedClassName, S); 3529 assert(InjectedClassName->isInjectedClassName() && 3530 "Broken injected-class-name"); 3531 } 3532 } 3533} 3534 3535void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3536 AdjustDeclIfTemplate(TagD); 3537 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3538 3539 if (isa<CXXRecordDecl>(Tag)) 3540 FieldCollector->FinishClass(); 3541 3542 // Exit this scope of this tag's definition. 3543 PopDeclContext(); 3544 3545 // Notify the consumer that we've defined a tag. 3546 Consumer.HandleTagDeclDefinition(Tag); 3547} 3548 3549// Note that FieldName may be null for anonymous bitfields. 3550bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3551 QualType FieldTy, const Expr *BitWidth) { 3552 3553 // C99 6.7.2.1p4 - verify the field type. 3554 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3555 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3556 // Handle incomplete types with specific error. 3557 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3558 return true; 3559 if (FieldName) 3560 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3561 << FieldName << FieldTy << BitWidth->getSourceRange(); 3562 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 3563 << FieldTy << BitWidth->getSourceRange(); 3564 } 3565 3566 // If the bit-width is type- or value-dependent, don't try to check 3567 // it now. 3568 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3569 return false; 3570 3571 llvm::APSInt Value; 3572 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3573 return true; 3574 3575 // Zero-width bitfield is ok for anonymous field. 3576 if (Value == 0 && FieldName) 3577 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3578 3579 if (Value.isSigned() && Value.isNegative()) { 3580 if (FieldName) 3581 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3582 << FieldName << Value.toString(10); 3583 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 3584 << Value.toString(10); 3585 } 3586 3587 if (!FieldTy->isDependentType()) { 3588 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3589 if (Value.getZExtValue() > TypeSize) { 3590 if (FieldName) 3591 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3592 << FieldName << (unsigned)TypeSize; 3593 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 3594 << (unsigned)TypeSize; 3595 } 3596 } 3597 3598 return false; 3599} 3600 3601/// ActOnField - Each field of a struct/union/class is passed into this in order 3602/// to create a FieldDecl object for it. 3603Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3604 SourceLocation DeclStart, 3605 Declarator &D, ExprTy *BitfieldWidth) { 3606 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3607 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3608 AS_public); 3609 return DeclPtrTy::make(Res); 3610} 3611 3612/// HandleField - Analyze a field of a C struct or a C++ data member. 3613/// 3614FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3615 SourceLocation DeclStart, 3616 Declarator &D, Expr *BitWidth, 3617 AccessSpecifier AS) { 3618 IdentifierInfo *II = D.getIdentifier(); 3619 SourceLocation Loc = DeclStart; 3620 if (II) Loc = D.getIdentifierLoc(); 3621 3622 QualType T = GetTypeForDeclarator(D, S); 3623 if (getLangOptions().CPlusPlus) 3624 CheckExtraCXXDefaultArguments(D); 3625 3626 DiagnoseFunctionSpecifiers(D); 3627 3628 if (D.getDeclSpec().isThreadSpecified()) 3629 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3630 3631 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3632 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3633 PrevDecl = 0; 3634 3635 FieldDecl *NewFD 3636 = CheckFieldDecl(II, T, Record, Loc, 3637 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3638 BitWidth, AS, PrevDecl, &D); 3639 if (NewFD->isInvalidDecl() && PrevDecl) { 3640 // Don't introduce NewFD into scope; there's already something 3641 // with the same name in the same scope. 3642 } else if (II) { 3643 PushOnScopeChains(NewFD, S); 3644 } else 3645 Record->addDecl(Context, NewFD); 3646 3647 return NewFD; 3648} 3649 3650/// \brief Build a new FieldDecl and check its well-formedness. 3651/// 3652/// This routine builds a new FieldDecl given the fields name, type, 3653/// record, etc. \p PrevDecl should refer to any previous declaration 3654/// with the same name and in the same scope as the field to be 3655/// created. 3656/// 3657/// \returns a new FieldDecl. 3658/// 3659/// \todo The Declarator argument is a hack. It will be removed once 3660FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3661 RecordDecl *Record, SourceLocation Loc, 3662 bool Mutable, Expr *BitWidth, 3663 AccessSpecifier AS, NamedDecl *PrevDecl, 3664 Declarator *D) { 3665 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3666 bool InvalidDecl = false; 3667 if (D) InvalidDecl = D->isInvalidType(); 3668 3669 // If we receive a broken type, recover by assuming 'int' and 3670 // marking this declaration as invalid. 3671 if (T.isNull()) { 3672 InvalidDecl = true; 3673 T = Context.IntTy; 3674 } 3675 3676 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3677 // than a variably modified type. 3678 if (T->isVariablyModifiedType()) { 3679 bool SizeIsNegative; 3680 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3681 SizeIsNegative); 3682 if (!FixedTy.isNull()) { 3683 Diag(Loc, diag::warn_illegal_constant_array_size); 3684 T = FixedTy; 3685 } else { 3686 if (SizeIsNegative) 3687 Diag(Loc, diag::err_typecheck_negative_array_size); 3688 else 3689 Diag(Loc, diag::err_typecheck_field_variable_size); 3690 T = Context.IntTy; 3691 InvalidDecl = true; 3692 } 3693 } 3694 3695 // Fields can not have abstract class types 3696 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3697 AbstractFieldType)) 3698 InvalidDecl = true; 3699 3700 // If this is declared as a bit-field, check the bit-field. 3701 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3702 InvalidDecl = true; 3703 DeleteExpr(BitWidth); 3704 BitWidth = 0; 3705 } 3706 3707 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3708 Mutable); 3709 if (InvalidDecl) 3710 NewFD->setInvalidDecl(); 3711 3712 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3713 Diag(Loc, diag::err_duplicate_member) << II; 3714 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3715 NewFD->setInvalidDecl(); 3716 Record->setInvalidDecl(); 3717 } 3718 3719 if (getLangOptions().CPlusPlus && !T->isPODType()) 3720 cast<CXXRecordDecl>(Record)->setPOD(false); 3721 3722 // FIXME: We need to pass in the attributes given an AST 3723 // representation, not a parser representation. 3724 if (D) 3725 ProcessDeclAttributes(NewFD, *D); 3726 3727 if (T.isObjCGCWeak()) 3728 Diag(Loc, diag::warn_attribute_weak_on_field); 3729 3730 NewFD->setAccess(AS); 3731 3732 // C++ [dcl.init.aggr]p1: 3733 // An aggregate is an array or a class (clause 9) with [...] no 3734 // private or protected non-static data members (clause 11). 3735 // A POD must be an aggregate. 3736 if (getLangOptions().CPlusPlus && 3737 (AS == AS_private || AS == AS_protected)) { 3738 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3739 CXXRecord->setAggregate(false); 3740 CXXRecord->setPOD(false); 3741 } 3742 3743 return NewFD; 3744} 3745 3746/// TranslateIvarVisibility - Translate visibility from a token ID to an 3747/// AST enum value. 3748static ObjCIvarDecl::AccessControl 3749TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3750 switch (ivarVisibility) { 3751 default: assert(0 && "Unknown visitibility kind"); 3752 case tok::objc_private: return ObjCIvarDecl::Private; 3753 case tok::objc_public: return ObjCIvarDecl::Public; 3754 case tok::objc_protected: return ObjCIvarDecl::Protected; 3755 case tok::objc_package: return ObjCIvarDecl::Package; 3756 } 3757} 3758 3759/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3760/// in order to create an IvarDecl object for it. 3761Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3762 SourceLocation DeclStart, 3763 Declarator &D, ExprTy *BitfieldWidth, 3764 tok::ObjCKeywordKind Visibility) { 3765 3766 IdentifierInfo *II = D.getIdentifier(); 3767 Expr *BitWidth = (Expr*)BitfieldWidth; 3768 SourceLocation Loc = DeclStart; 3769 if (II) Loc = D.getIdentifierLoc(); 3770 3771 // FIXME: Unnamed fields can be handled in various different ways, for 3772 // example, unnamed unions inject all members into the struct namespace! 3773 3774 QualType T = GetTypeForDeclarator(D, S); 3775 3776 if (BitWidth) { 3777 // 6.7.2.1p3, 6.7.2.1p4 3778 if (VerifyBitField(Loc, II, T, BitWidth)) { 3779 D.setInvalidType(); 3780 DeleteExpr(BitWidth); 3781 BitWidth = 0; 3782 } 3783 } else { 3784 // Not a bitfield. 3785 3786 // validate II. 3787 3788 } 3789 3790 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3791 // than a variably modified type. 3792 if (T->isVariablyModifiedType()) { 3793 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3794 D.setInvalidType(); 3795 } 3796 3797 // Get the visibility (access control) for this ivar. 3798 ObjCIvarDecl::AccessControl ac = 3799 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3800 : ObjCIvarDecl::None; 3801 3802 // Construct the decl. 3803 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3804 (Expr *)BitfieldWidth); 3805 3806 if (II) { 3807 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3808 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3809 && !isa<TagDecl>(PrevDecl)) { 3810 Diag(Loc, diag::err_duplicate_member) << II; 3811 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3812 NewID->setInvalidDecl(); 3813 } 3814 } 3815 3816 // Process attributes attached to the ivar. 3817 ProcessDeclAttributes(NewID, D); 3818 3819 if (D.isInvalidType()) 3820 NewID->setInvalidDecl(); 3821 3822 if (II) { 3823 // FIXME: When interfaces are DeclContexts, we'll need to add 3824 // these to the interface. 3825 S->AddDecl(DeclPtrTy::make(NewID)); 3826 IdResolver.AddDecl(NewID); 3827 } 3828 3829 return DeclPtrTy::make(NewID); 3830} 3831 3832void Sema::ActOnFields(Scope* S, 3833 SourceLocation RecLoc, DeclPtrTy RecDecl, 3834 DeclPtrTy *Fields, unsigned NumFields, 3835 SourceLocation LBrac, SourceLocation RBrac, 3836 AttributeList *Attr) { 3837 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3838 assert(EnclosingDecl && "missing record or interface decl"); 3839 3840 // If the decl this is being inserted into is invalid, then it may be a 3841 // redeclaration or some other bogus case. Don't try to add fields to it. 3842 if (EnclosingDecl->isInvalidDecl()) { 3843 // FIXME: Deallocate fields? 3844 return; 3845 } 3846 3847 3848 // Verify that all the fields are okay. 3849 unsigned NumNamedMembers = 0; 3850 llvm::SmallVector<FieldDecl*, 32> RecFields; 3851 3852 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3853 for (unsigned i = 0; i != NumFields; ++i) { 3854 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3855 3856 // Get the type for the field. 3857 Type *FDTy = FD->getType().getTypePtr(); 3858 3859 if (!FD->isAnonymousStructOrUnion()) { 3860 // Remember all fields written by the user. 3861 RecFields.push_back(FD); 3862 } 3863 3864 // If the field is already invalid for some reason, don't emit more 3865 // diagnostics about it. 3866 if (FD->isInvalidDecl()) 3867 continue; 3868 3869 // C99 6.7.2.1p2: 3870 // A structure or union shall not contain a member with 3871 // incomplete or function type (hence, a structure shall not 3872 // contain an instance of itself, but may contain a pointer to 3873 // an instance of itself), except that the last member of a 3874 // structure with more than one named member may have incomplete 3875 // array type; such a structure (and any union containing, 3876 // possibly recursively, a member that is such a structure) 3877 // shall not be a member of a structure or an element of an 3878 // array. 3879 if (FDTy->isFunctionType()) { 3880 // Field declared as a function. 3881 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3882 << FD->getDeclName(); 3883 FD->setInvalidDecl(); 3884 EnclosingDecl->setInvalidDecl(); 3885 continue; 3886 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3887 Record && Record->isStruct()) { 3888 // Flexible array member. 3889 if (NumNamedMembers < 1) { 3890 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3891 << FD->getDeclName(); 3892 FD->setInvalidDecl(); 3893 EnclosingDecl->setInvalidDecl(); 3894 continue; 3895 } 3896 // Okay, we have a legal flexible array member at the end of the struct. 3897 if (Record) 3898 Record->setHasFlexibleArrayMember(true); 3899 } else if (!FDTy->isDependentType() && 3900 RequireCompleteType(FD->getLocation(), FD->getType(), 3901 diag::err_field_incomplete)) { 3902 // Incomplete type 3903 FD->setInvalidDecl(); 3904 EnclosingDecl->setInvalidDecl(); 3905 continue; 3906 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3907 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3908 // If this is a member of a union, then entire union becomes "flexible". 3909 if (Record && Record->isUnion()) { 3910 Record->setHasFlexibleArrayMember(true); 3911 } else { 3912 // If this is a struct/class and this is not the last element, reject 3913 // it. Note that GCC supports variable sized arrays in the middle of 3914 // structures. 3915 if (i != NumFields-1) 3916 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3917 << FD->getDeclName() << FD->getType(); 3918 else { 3919 // We support flexible arrays at the end of structs in 3920 // other structs as an extension. 3921 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3922 << FD->getDeclName(); 3923 if (Record) 3924 Record->setHasFlexibleArrayMember(true); 3925 } 3926 } 3927 } 3928 } else if (FDTy->isObjCInterfaceType()) { 3929 /// A field cannot be an Objective-c object 3930 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3931 FD->setInvalidDecl(); 3932 EnclosingDecl->setInvalidDecl(); 3933 continue; 3934 } 3935 // Keep track of the number of named members. 3936 if (FD->getIdentifier()) 3937 ++NumNamedMembers; 3938 } 3939 3940 // Okay, we successfully defined 'Record'. 3941 if (Record) { 3942 Record->completeDefinition(Context); 3943 } else { 3944 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3945 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3946 ID->setIVarList(ClsFields, RecFields.size(), Context); 3947 ID->setLocEnd(RBrac); 3948 3949 // Must enforce the rule that ivars in the base classes may not be 3950 // duplicates. 3951 if (ID->getSuperClass()) { 3952 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3953 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3954 ObjCIvarDecl* Ivar = (*IVI); 3955 IdentifierInfo *II = Ivar->getIdentifier(); 3956 ObjCIvarDecl* prevIvar = 3957 ID->getSuperClass()->lookupInstanceVariable(Context, II); 3958 if (prevIvar) { 3959 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3960 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3961 } 3962 } 3963 } 3964 } else if (ObjCImplementationDecl *IMPDecl = 3965 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3966 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3967 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) { 3968 // FIXME: Set the DeclContext correctly when we build the 3969 // declarations. 3970 ClsFields[I]->setLexicalDeclContext(IMPDecl); 3971 IMPDecl->addDecl(Context, ClsFields[I]); 3972 } 3973 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3974 } 3975 } 3976 3977 if (Attr) 3978 ProcessDeclAttributeList(Record, Attr); 3979} 3980 3981EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 3982 EnumConstantDecl *LastEnumConst, 3983 SourceLocation IdLoc, 3984 IdentifierInfo *Id, 3985 ExprArg val) { 3986 Expr *Val = (Expr *)val.get(); 3987 3988 llvm::APSInt EnumVal(32); 3989 QualType EltTy; 3990 if (Val && !Val->isTypeDependent()) { 3991 // Make sure to promote the operand type to int. 3992 UsualUnaryConversions(Val); 3993 if (Val != val.get()) { 3994 val.release(); 3995 val = Val; 3996 } 3997 3998 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3999 SourceLocation ExpLoc; 4000 if (!Val->isValueDependent() && 4001 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4002 Val = 0; 4003 } else { 4004 EltTy = Val->getType(); 4005 } 4006 } 4007 4008 if (!Val) { 4009 if (LastEnumConst) { 4010 // Assign the last value + 1. 4011 EnumVal = LastEnumConst->getInitVal(); 4012 ++EnumVal; 4013 4014 // Check for overflow on increment. 4015 if (EnumVal < LastEnumConst->getInitVal()) 4016 Diag(IdLoc, diag::warn_enum_value_overflow); 4017 4018 EltTy = LastEnumConst->getType(); 4019 } else { 4020 // First value, set to zero. 4021 EltTy = Context.IntTy; 4022 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4023 } 4024 } 4025 4026 val.release(); 4027 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4028 Val, EnumVal); 4029} 4030 4031 4032Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4033 DeclPtrTy lastEnumConst, 4034 SourceLocation IdLoc, 4035 IdentifierInfo *Id, 4036 SourceLocation EqualLoc, ExprTy *val) { 4037 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4038 EnumConstantDecl *LastEnumConst = 4039 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4040 Expr *Val = static_cast<Expr*>(val); 4041 4042 // The scope passed in may not be a decl scope. Zip up the scope tree until 4043 // we find one that is. 4044 S = getNonFieldDeclScope(S); 4045 4046 // Verify that there isn't already something declared with this name in this 4047 // scope. 4048 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4049 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4050 // Maybe we will complain about the shadowed template parameter. 4051 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4052 // Just pretend that we didn't see the previous declaration. 4053 PrevDecl = 0; 4054 } 4055 4056 if (PrevDecl) { 4057 // When in C++, we may get a TagDecl with the same name; in this case the 4058 // enum constant will 'hide' the tag. 4059 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4060 "Received TagDecl when not in C++!"); 4061 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4062 if (isa<EnumConstantDecl>(PrevDecl)) 4063 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4064 else 4065 Diag(IdLoc, diag::err_redefinition) << Id; 4066 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4067 if (Val) Val->Destroy(Context); 4068 return DeclPtrTy(); 4069 } 4070 } 4071 4072 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4073 IdLoc, Id, Owned(Val)); 4074 4075 // Register this decl in the current scope stack. 4076 if (New) 4077 PushOnScopeChains(New, S); 4078 4079 return DeclPtrTy::make(New); 4080} 4081 4082// FIXME: For consistency with ActOnFields(), we should have the parser 4083// pass in the source location for the left/right braces. 4084void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4085 DeclPtrTy *Elements, unsigned NumElements) { 4086 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4087 QualType EnumType = Context.getTypeDeclType(Enum); 4088 4089 // TODO: If the result value doesn't fit in an int, it must be a long or long 4090 // long value. ISO C does not support this, but GCC does as an extension, 4091 // emit a warning. 4092 unsigned IntWidth = Context.Target.getIntWidth(); 4093 4094 // Verify that all the values are okay, compute the size of the values, and 4095 // reverse the list. 4096 unsigned NumNegativeBits = 0; 4097 unsigned NumPositiveBits = 0; 4098 4099 // Keep track of whether all elements have type int. 4100 bool AllElementsInt = true; 4101 4102 for (unsigned i = 0; i != NumElements; ++i) { 4103 EnumConstantDecl *ECD = 4104 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4105 if (!ECD) continue; // Already issued a diagnostic. 4106 4107 // If the enum value doesn't fit in an int, emit an extension warning. 4108 const llvm::APSInt &InitVal = ECD->getInitVal(); 4109 assert(InitVal.getBitWidth() >= IntWidth && 4110 "Should have promoted value to int"); 4111 if (InitVal.getBitWidth() > IntWidth) { 4112 llvm::APSInt V(InitVal); 4113 V.trunc(IntWidth); 4114 V.extend(InitVal.getBitWidth()); 4115 if (V != InitVal) 4116 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4117 << InitVal.toString(10); 4118 } 4119 4120 // Keep track of the size of positive and negative values. 4121 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4122 NumPositiveBits = std::max(NumPositiveBits, 4123 (unsigned)InitVal.getActiveBits()); 4124 else 4125 NumNegativeBits = std::max(NumNegativeBits, 4126 (unsigned)InitVal.getMinSignedBits()); 4127 4128 // Keep track of whether every enum element has type int (very commmon). 4129 if (AllElementsInt) 4130 AllElementsInt = ECD->getType() == Context.IntTy; 4131 } 4132 4133 // Figure out the type that should be used for this enum. 4134 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4135 QualType BestType; 4136 unsigned BestWidth; 4137 4138 if (NumNegativeBits) { 4139 // If there is a negative value, figure out the smallest integer type (of 4140 // int/long/longlong) that fits. 4141 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4142 BestType = Context.IntTy; 4143 BestWidth = IntWidth; 4144 } else { 4145 BestWidth = Context.Target.getLongWidth(); 4146 4147 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4148 BestType = Context.LongTy; 4149 else { 4150 BestWidth = Context.Target.getLongLongWidth(); 4151 4152 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4153 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4154 BestType = Context.LongLongTy; 4155 } 4156 } 4157 } else { 4158 // If there is no negative value, figure out which of uint, ulong, ulonglong 4159 // fits. 4160 if (NumPositiveBits <= IntWidth) { 4161 BestType = Context.UnsignedIntTy; 4162 BestWidth = IntWidth; 4163 } else if (NumPositiveBits <= 4164 (BestWidth = Context.Target.getLongWidth())) { 4165 BestType = Context.UnsignedLongTy; 4166 } else { 4167 BestWidth = Context.Target.getLongLongWidth(); 4168 assert(NumPositiveBits <= BestWidth && 4169 "How could an initializer get larger than ULL?"); 4170 BestType = Context.UnsignedLongLongTy; 4171 } 4172 } 4173 4174 // Loop over all of the enumerator constants, changing their types to match 4175 // the type of the enum if needed. 4176 for (unsigned i = 0; i != NumElements; ++i) { 4177 EnumConstantDecl *ECD = 4178 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4179 if (!ECD) continue; // Already issued a diagnostic. 4180 4181 // Standard C says the enumerators have int type, but we allow, as an 4182 // extension, the enumerators to be larger than int size. If each 4183 // enumerator value fits in an int, type it as an int, otherwise type it the 4184 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4185 // that X has type 'int', not 'unsigned'. 4186 if (ECD->getType() == Context.IntTy) { 4187 // Make sure the init value is signed. 4188 llvm::APSInt IV = ECD->getInitVal(); 4189 IV.setIsSigned(true); 4190 ECD->setInitVal(IV); 4191 4192 if (getLangOptions().CPlusPlus) 4193 // C++ [dcl.enum]p4: Following the closing brace of an 4194 // enum-specifier, each enumerator has the type of its 4195 // enumeration. 4196 ECD->setType(EnumType); 4197 continue; // Already int type. 4198 } 4199 4200 // Determine whether the value fits into an int. 4201 llvm::APSInt InitVal = ECD->getInitVal(); 4202 bool FitsInInt; 4203 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4204 FitsInInt = InitVal.getActiveBits() < IntWidth; 4205 else 4206 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4207 4208 // If it fits into an integer type, force it. Otherwise force it to match 4209 // the enum decl type. 4210 QualType NewTy; 4211 unsigned NewWidth; 4212 bool NewSign; 4213 if (FitsInInt) { 4214 NewTy = Context.IntTy; 4215 NewWidth = IntWidth; 4216 NewSign = true; 4217 } else if (ECD->getType() == BestType) { 4218 // Already the right type! 4219 if (getLangOptions().CPlusPlus) 4220 // C++ [dcl.enum]p4: Following the closing brace of an 4221 // enum-specifier, each enumerator has the type of its 4222 // enumeration. 4223 ECD->setType(EnumType); 4224 continue; 4225 } else { 4226 NewTy = BestType; 4227 NewWidth = BestWidth; 4228 NewSign = BestType->isSignedIntegerType(); 4229 } 4230 4231 // Adjust the APSInt value. 4232 InitVal.extOrTrunc(NewWidth); 4233 InitVal.setIsSigned(NewSign); 4234 ECD->setInitVal(InitVal); 4235 4236 // Adjust the Expr initializer and type. 4237 if (ECD->getInitExpr()) 4238 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4239 /*isLvalue=*/false)); 4240 if (getLangOptions().CPlusPlus) 4241 // C++ [dcl.enum]p4: Following the closing brace of an 4242 // enum-specifier, each enumerator has the type of its 4243 // enumeration. 4244 ECD->setType(EnumType); 4245 else 4246 ECD->setType(NewTy); 4247 } 4248 4249 Enum->completeDefinition(Context, BestType); 4250} 4251 4252Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4253 ExprArg expr) { 4254 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4255 4256 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4257 Loc, AsmString)); 4258} 4259 4260