SemaDecl.cpp revision b8f746865cb6dde04d4d03557be5ccad693a8a81
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/Parse/DeclSpec.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31using namespace clang; 32 33/// getDeclName - Return a pretty name for the specified decl if possible, or 34/// an empty string if not. This is used for pretty crash reporting. 35std::string Sema::getDeclName(DeclPtrTy d) { 36 Decl *D = d.getAs<Decl>(); 37 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 38 return DN->getQualifiedNameAsString(); 39 return ""; 40} 41 42Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 43 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 44} 45 46/// \brief If the identifier refers to a type name within this scope, 47/// return the declaration of that type. 48/// 49/// This routine performs ordinary name lookup of the identifier II 50/// within the given scope, with optional C++ scope specifier SS, to 51/// determine whether the name refers to a type. If so, returns an 52/// opaque pointer (actually a QualType) corresponding to that 53/// type. Otherwise, returns NULL. 54/// 55/// If name lookup results in an ambiguity, this routine will complain 56/// and then return NULL. 57Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 58 Scope *S, const CXXScopeSpec *SS) { 59 // C++ [temp.res]p3: 60 // A qualified-id that refers to a type and in which the 61 // nested-name-specifier depends on a template-parameter (14.6.2) 62 // shall be prefixed by the keyword typename to indicate that the 63 // qualified-id denotes a type, forming an 64 // elaborated-type-specifier (7.1.5.3). 65 // 66 // We therefore do not perform any name lookup up SS is a dependent 67 // scope name. FIXME: we will need to perform a special kind of 68 // lookup if the scope specifier names a member of the current 69 // instantiation. 70 if (SS && isDependentScopeSpecifier(*SS)) 71 return 0; 72 73 NamedDecl *IIDecl = 0; 74 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 75 false, false); 76 switch (Result.getKind()) { 77 case LookupResult::NotFound: 78 case LookupResult::FoundOverloaded: 79 return 0; 80 81 case LookupResult::AmbiguousBaseSubobjectTypes: 82 case LookupResult::AmbiguousBaseSubobjects: 83 case LookupResult::AmbiguousReference: { 84 // Look to see if we have a type anywhere in the list of results. 85 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 86 Res != ResEnd; ++Res) { 87 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 88 IIDecl = *Res; 89 break; 90 } 91 } 92 93 if (!IIDecl) { 94 // None of the entities we found is a type, so there is no way 95 // to even assume that the result is a type. In this case, don't 96 // complain about the ambiguity. The parser will either try to 97 // perform this lookup again (e.g., as an object name), which 98 // will produce the ambiguity, or will complain that it expected 99 // a type name. 100 Result.Destroy(); 101 return 0; 102 } 103 104 // We found a type within the ambiguous lookup; diagnose the 105 // ambiguity and then return that type. This might be the right 106 // answer, or it might not be, but it suppresses any attempt to 107 // perform the name lookup again. 108 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 109 break; 110 } 111 112 case LookupResult::Found: 113 IIDecl = Result.getAsDecl(); 114 break; 115 } 116 117 if (IIDecl) { 118 QualType T; 119 120 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 121 // Check whether we can use this type 122 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 123 124 T = Context.getTypeDeclType(TD); 125 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 126 // Check whether we can use this interface. 127 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 128 129 T = Context.getObjCInterfaceType(IDecl); 130 } else 131 return 0; 132 133 if (SS) 134 T = getQualifiedNameType(*SS, T); 135 136 return T.getAsOpaquePtr(); 137 } 138 139 return 0; 140} 141 142/// isTagName() - This method is called *for error recovery purposes only* 143/// to determine if the specified name is a valid tag name ("struct foo"). If 144/// so, this returns the TST for the tag corresponding to it (TST_enum, 145/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 146/// where the user forgot to specify the tag. 147DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 148 // Do a tag name lookup in this scope. 149 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 150 if (R.getKind() == LookupResult::Found) 151 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 152 switch (TD->getTagKind()) { 153 case TagDecl::TK_struct: return DeclSpec::TST_struct; 154 case TagDecl::TK_union: return DeclSpec::TST_union; 155 case TagDecl::TK_class: return DeclSpec::TST_class; 156 case TagDecl::TK_enum: return DeclSpec::TST_enum; 157 } 158 } 159 160 return DeclSpec::TST_unspecified; 161} 162 163 164 165DeclContext *Sema::getContainingDC(DeclContext *DC) { 166 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 167 // A C++ out-of-line method will return to the file declaration context. 168 if (MD->isOutOfLineDefinition()) 169 return MD->getLexicalDeclContext(); 170 171 // A C++ inline method is parsed *after* the topmost class it was declared 172 // in is fully parsed (it's "complete"). 173 // The parsing of a C++ inline method happens at the declaration context of 174 // the topmost (non-nested) class it is lexically declared in. 175 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 176 DC = MD->getParent(); 177 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 178 DC = RD; 179 180 // Return the declaration context of the topmost class the inline method is 181 // declared in. 182 return DC; 183 } 184 185 if (isa<ObjCMethodDecl>(DC)) 186 return Context.getTranslationUnitDecl(); 187 188 return DC->getLexicalParent(); 189} 190 191void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 192 assert(getContainingDC(DC) == CurContext && 193 "The next DeclContext should be lexically contained in the current one."); 194 CurContext = DC; 195 S->setEntity(DC); 196} 197 198void Sema::PopDeclContext() { 199 assert(CurContext && "DeclContext imbalance!"); 200 201 CurContext = getContainingDC(CurContext); 202} 203 204/// \brief Determine whether we allow overloading of the function 205/// PrevDecl with another declaration. 206/// 207/// This routine determines whether overloading is possible, not 208/// whether some new function is actually an overload. It will return 209/// true in C++ (where we can always provide overloads) or, as an 210/// extension, in C when the previous function is already an 211/// overloaded function declaration or has the "overloadable" 212/// attribute. 213static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 214 if (Context.getLangOptions().CPlusPlus) 215 return true; 216 217 if (isa<OverloadedFunctionDecl>(PrevDecl)) 218 return true; 219 220 return PrevDecl->getAttr<OverloadableAttr>() != 0; 221} 222 223/// Add this decl to the scope shadowed decl chains. 224void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 225 // Move up the scope chain until we find the nearest enclosing 226 // non-transparent context. The declaration will be introduced into this 227 // scope. 228 while (S->getEntity() && 229 ((DeclContext *)S->getEntity())->isTransparentContext()) 230 S = S->getParent(); 231 232 S->AddDecl(DeclPtrTy::make(D)); 233 234 // Add scoped declarations into their context, so that they can be 235 // found later. Declarations without a context won't be inserted 236 // into any context. 237 CurContext->addDecl(Context, D); 238 239 // C++ [basic.scope]p4: 240 // -- exactly one declaration shall declare a class name or 241 // enumeration name that is not a typedef name and the other 242 // declarations shall all refer to the same object or 243 // enumerator, or all refer to functions and function templates; 244 // in this case the class name or enumeration name is hidden. 245 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 246 // We are pushing the name of a tag (enum or class). 247 if (CurContext->getLookupContext() 248 == TD->getDeclContext()->getLookupContext()) { 249 // We're pushing the tag into the current context, which might 250 // require some reshuffling in the identifier resolver. 251 IdentifierResolver::iterator 252 I = IdResolver.begin(TD->getDeclName()), 253 IEnd = IdResolver.end(); 254 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 255 NamedDecl *PrevDecl = *I; 256 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 257 PrevDecl = *I, ++I) { 258 if (TD->declarationReplaces(*I)) { 259 // This is a redeclaration. Remove it from the chain and 260 // break out, so that we'll add in the shadowed 261 // declaration. 262 S->RemoveDecl(DeclPtrTy::make(*I)); 263 if (PrevDecl == *I) { 264 IdResolver.RemoveDecl(*I); 265 IdResolver.AddDecl(TD); 266 return; 267 } else { 268 IdResolver.RemoveDecl(*I); 269 break; 270 } 271 } 272 } 273 274 // There is already a declaration with the same name in the same 275 // scope, which is not a tag declaration. It must be found 276 // before we find the new declaration, so insert the new 277 // declaration at the end of the chain. 278 IdResolver.AddShadowedDecl(TD, PrevDecl); 279 280 return; 281 } 282 } 283 } else if (isa<FunctionDecl>(D) && 284 AllowOverloadingOfFunction(D, Context)) { 285 // We are pushing the name of a function, which might be an 286 // overloaded name. 287 FunctionDecl *FD = cast<FunctionDecl>(D); 288 IdentifierResolver::iterator Redecl 289 = std::find_if(IdResolver.begin(FD->getDeclName()), 290 IdResolver.end(), 291 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 292 FD)); 293 if (Redecl != IdResolver.end() && 294 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 295 // There is already a declaration of a function on our 296 // IdResolver chain. Replace it with this declaration. 297 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 298 IdResolver.RemoveDecl(*Redecl); 299 } 300 } 301 302 IdResolver.AddDecl(D); 303} 304 305void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 306 if (S->decl_empty()) return; 307 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 308 "Scope shouldn't contain decls!"); 309 310 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 311 I != E; ++I) { 312 Decl *TmpD = (*I).getAs<Decl>(); 313 assert(TmpD && "This decl didn't get pushed??"); 314 315 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 316 NamedDecl *D = cast<NamedDecl>(TmpD); 317 318 if (!D->getDeclName()) continue; 319 320 // Remove this name from our lexical scope. 321 IdResolver.RemoveDecl(D); 322 } 323} 324 325/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 326/// return 0 if one not found. 327ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 328 // The third "scope" argument is 0 since we aren't enabling lazy built-in 329 // creation from this context. 330 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 331 332 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 333} 334 335/// getNonFieldDeclScope - Retrieves the innermost scope, starting 336/// from S, where a non-field would be declared. This routine copes 337/// with the difference between C and C++ scoping rules in structs and 338/// unions. For example, the following code is well-formed in C but 339/// ill-formed in C++: 340/// @code 341/// struct S6 { 342/// enum { BAR } e; 343/// }; 344/// 345/// void test_S6() { 346/// struct S6 a; 347/// a.e = BAR; 348/// } 349/// @endcode 350/// For the declaration of BAR, this routine will return a different 351/// scope. The scope S will be the scope of the unnamed enumeration 352/// within S6. In C++, this routine will return the scope associated 353/// with S6, because the enumeration's scope is a transparent 354/// context but structures can contain non-field names. In C, this 355/// routine will return the translation unit scope, since the 356/// enumeration's scope is a transparent context and structures cannot 357/// contain non-field names. 358Scope *Sema::getNonFieldDeclScope(Scope *S) { 359 while (((S->getFlags() & Scope::DeclScope) == 0) || 360 (S->getEntity() && 361 ((DeclContext *)S->getEntity())->isTransparentContext()) || 362 (S->isClassScope() && !getLangOptions().CPlusPlus)) 363 S = S->getParent(); 364 return S; 365} 366 367void Sema::InitBuiltinVaListType() { 368 if (!Context.getBuiltinVaListType().isNull()) 369 return; 370 371 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 372 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 373 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 374 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 375} 376 377/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 378/// file scope. lazily create a decl for it. ForRedeclaration is true 379/// if we're creating this built-in in anticipation of redeclaring the 380/// built-in. 381NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 382 Scope *S, bool ForRedeclaration, 383 SourceLocation Loc) { 384 Builtin::ID BID = (Builtin::ID)bid; 385 386 if (Context.BuiltinInfo.hasVAListUse(BID)) 387 InitBuiltinVaListType(); 388 389 Builtin::Context::GetBuiltinTypeError Error; 390 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 391 switch (Error) { 392 case Builtin::Context::GE_None: 393 // Okay 394 break; 395 396 case Builtin::Context::GE_Missing_FILE: 397 if (ForRedeclaration) 398 Diag(Loc, diag::err_implicit_decl_requires_stdio) 399 << Context.BuiltinInfo.GetName(BID); 400 return 0; 401 } 402 403 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 404 Diag(Loc, diag::ext_implicit_lib_function_decl) 405 << Context.BuiltinInfo.GetName(BID) 406 << R; 407 if (Context.BuiltinInfo.getHeaderName(BID) && 408 Diags.getDiagnosticMapping(diag::ext_implicit_lib_function_decl) 409 != diag::MAP_IGNORE) 410 Diag(Loc, diag::note_please_include_header) 411 << Context.BuiltinInfo.getHeaderName(BID) 412 << Context.BuiltinInfo.GetName(BID); 413 } 414 415 FunctionDecl *New = FunctionDecl::Create(Context, 416 Context.getTranslationUnitDecl(), 417 Loc, II, R, 418 FunctionDecl::Extern, false, 419 /*hasPrototype=*/true); 420 New->setImplicit(); 421 422 // Create Decl objects for each parameter, adding them to the 423 // FunctionDecl. 424 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 425 llvm::SmallVector<ParmVarDecl*, 16> Params; 426 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 427 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 428 FT->getArgType(i), VarDecl::None, 0)); 429 New->setParams(Context, &Params[0], Params.size()); 430 } 431 432 AddKnownFunctionAttributes(New); 433 434 // TUScope is the translation-unit scope to insert this function into. 435 // FIXME: This is hideous. We need to teach PushOnScopeChains to 436 // relate Scopes to DeclContexts, and probably eliminate CurContext 437 // entirely, but we're not there yet. 438 DeclContext *SavedContext = CurContext; 439 CurContext = Context.getTranslationUnitDecl(); 440 PushOnScopeChains(New, TUScope); 441 CurContext = SavedContext; 442 return New; 443} 444 445/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 446/// everything from the standard library is defined. 447NamespaceDecl *Sema::GetStdNamespace() { 448 if (!StdNamespace) { 449 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 450 DeclContext *Global = Context.getTranslationUnitDecl(); 451 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 452 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 453 } 454 return StdNamespace; 455} 456 457/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 458/// same name and scope as a previous declaration 'Old'. Figure out 459/// how to resolve this situation, merging decls or emitting 460/// diagnostics as appropriate. Returns true if there was an error, 461/// false otherwise. 462/// 463bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 464 bool objc_types = false; 465 // Allow multiple definitions for ObjC built-in typedefs. 466 // FIXME: Verify the underlying types are equivalent! 467 if (getLangOptions().ObjC1) { 468 const IdentifierInfo *TypeID = New->getIdentifier(); 469 switch (TypeID->getLength()) { 470 default: break; 471 case 2: 472 if (!TypeID->isStr("id")) 473 break; 474 Context.setObjCIdType(New); 475 objc_types = true; 476 break; 477 case 5: 478 if (!TypeID->isStr("Class")) 479 break; 480 Context.setObjCClassType(New); 481 objc_types = true; 482 return false; 483 case 3: 484 if (!TypeID->isStr("SEL")) 485 break; 486 Context.setObjCSelType(New); 487 objc_types = true; 488 return false; 489 case 8: 490 if (!TypeID->isStr("Protocol")) 491 break; 492 Context.setObjCProtoType(New->getUnderlyingType()); 493 objc_types = true; 494 return false; 495 } 496 // Fall through - the typedef name was not a builtin type. 497 } 498 // Verify the old decl was also a type. 499 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 500 if (!Old) { 501 Diag(New->getLocation(), diag::err_redefinition_different_kind) 502 << New->getDeclName(); 503 if (!objc_types) 504 Diag(OldD->getLocation(), diag::note_previous_definition); 505 return true; 506 } 507 508 // Determine the "old" type we'll use for checking and diagnostics. 509 QualType OldType; 510 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 511 OldType = OldTypedef->getUnderlyingType(); 512 else 513 OldType = Context.getTypeDeclType(Old); 514 515 // If the typedef types are not identical, reject them in all languages and 516 // with any extensions enabled. 517 518 if (OldType != New->getUnderlyingType() && 519 Context.getCanonicalType(OldType) != 520 Context.getCanonicalType(New->getUnderlyingType())) { 521 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 522 << New->getUnderlyingType() << OldType; 523 if (!objc_types) 524 Diag(Old->getLocation(), diag::note_previous_definition); 525 return true; 526 } 527 if (objc_types) return false; 528 if (getLangOptions().Microsoft) return false; 529 530 // C++ [dcl.typedef]p2: 531 // In a given non-class scope, a typedef specifier can be used to 532 // redefine the name of any type declared in that scope to refer 533 // to the type to which it already refers. 534 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 535 return false; 536 537 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 538 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 539 // *either* declaration is in a system header. The code below implements 540 // this adhoc compatibility rule. FIXME: The following code will not 541 // work properly when compiling ".i" files (containing preprocessed output). 542 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 543 SourceManager &SrcMgr = Context.getSourceManager(); 544 if (SrcMgr.isInSystemHeader(Old->getLocation())) 545 return false; 546 if (SrcMgr.isInSystemHeader(New->getLocation())) 547 return false; 548 } 549 550 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 551 Diag(Old->getLocation(), diag::note_previous_definition); 552 return true; 553} 554 555/// DeclhasAttr - returns true if decl Declaration already has the target 556/// attribute. 557static bool DeclHasAttr(const Decl *decl, const Attr *target) { 558 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 559 if (attr->getKind() == target->getKind()) 560 return true; 561 562 return false; 563} 564 565/// MergeAttributes - append attributes from the Old decl to the New one. 566static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 567 Attr *attr = const_cast<Attr*>(Old->getAttrs()); 568 569 while (attr) { 570 Attr *tmp = attr; 571 attr = attr->getNext(); 572 573 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 574 tmp->setInherited(true); 575 New->addAttr(tmp); 576 } else { 577 tmp->setNext(0); 578 tmp->Destroy(C); 579 } 580 } 581 582 Old->invalidateAttrs(); 583} 584 585/// Used in MergeFunctionDecl to keep track of function parameters in 586/// C. 587struct GNUCompatibleParamWarning { 588 ParmVarDecl *OldParm; 589 ParmVarDecl *NewParm; 590 QualType PromotedType; 591}; 592 593/// MergeFunctionDecl - We just parsed a function 'New' from 594/// declarator D which has the same name and scope as a previous 595/// declaration 'Old'. Figure out how to resolve this situation, 596/// merging decls or emitting diagnostics as appropriate. 597/// 598/// In C++, New and Old must be declarations that are not 599/// overloaded. Use IsOverload to determine whether New and Old are 600/// overloaded, and to select the Old declaration that New should be 601/// merged with. 602/// 603/// Returns true if there was an error, false otherwise. 604bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 605 assert(!isa<OverloadedFunctionDecl>(OldD) && 606 "Cannot merge with an overloaded function declaration"); 607 608 // Verify the old decl was also a function. 609 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 610 if (!Old) { 611 Diag(New->getLocation(), diag::err_redefinition_different_kind) 612 << New->getDeclName(); 613 Diag(OldD->getLocation(), diag::note_previous_definition); 614 return true; 615 } 616 617 // Determine whether the previous declaration was a definition, 618 // implicit declaration, or a declaration. 619 diag::kind PrevDiag; 620 if (Old->isThisDeclarationADefinition()) 621 PrevDiag = diag::note_previous_definition; 622 else if (Old->isImplicit()) 623 PrevDiag = diag::note_previous_implicit_declaration; 624 else 625 PrevDiag = diag::note_previous_declaration; 626 627 QualType OldQType = Context.getCanonicalType(Old->getType()); 628 QualType NewQType = Context.getCanonicalType(New->getType()); 629 630 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 631 New->getStorageClass() == FunctionDecl::Static && 632 Old->getStorageClass() != FunctionDecl::Static) { 633 Diag(New->getLocation(), diag::err_static_non_static) 634 << New; 635 Diag(Old->getLocation(), PrevDiag); 636 return true; 637 } 638 639 if (getLangOptions().CPlusPlus) { 640 // (C++98 13.1p2): 641 // Certain function declarations cannot be overloaded: 642 // -- Function declarations that differ only in the return type 643 // cannot be overloaded. 644 QualType OldReturnType 645 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 646 QualType NewReturnType 647 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 648 if (OldReturnType != NewReturnType) { 649 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 650 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 651 return true; 652 } 653 654 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 655 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 656 if (OldMethod && NewMethod && 657 OldMethod->getLexicalDeclContext() == 658 NewMethod->getLexicalDeclContext()) { 659 // -- Member function declarations with the same name and the 660 // same parameter types cannot be overloaded if any of them 661 // is a static member function declaration. 662 if (OldMethod->isStatic() || NewMethod->isStatic()) { 663 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 664 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 665 return true; 666 } 667 668 // C++ [class.mem]p1: 669 // [...] A member shall not be declared twice in the 670 // member-specification, except that a nested class or member 671 // class template can be declared and then later defined. 672 unsigned NewDiag; 673 if (isa<CXXConstructorDecl>(OldMethod)) 674 NewDiag = diag::err_constructor_redeclared; 675 else if (isa<CXXDestructorDecl>(NewMethod)) 676 NewDiag = diag::err_destructor_redeclared; 677 else if (isa<CXXConversionDecl>(NewMethod)) 678 NewDiag = diag::err_conv_function_redeclared; 679 else 680 NewDiag = diag::err_member_redeclared; 681 682 Diag(New->getLocation(), NewDiag); 683 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 684 } 685 686 // (C++98 8.3.5p3): 687 // All declarations for a function shall agree exactly in both the 688 // return type and the parameter-type-list. 689 if (OldQType == NewQType) 690 return MergeCompatibleFunctionDecls(New, Old); 691 692 // Fall through for conflicting redeclarations and redefinitions. 693 } 694 695 // C: Function types need to be compatible, not identical. This handles 696 // duplicate function decls like "void f(int); void f(enum X);" properly. 697 if (!getLangOptions().CPlusPlus && 698 Context.typesAreCompatible(OldQType, NewQType)) { 699 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 700 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 701 const FunctionProtoType *OldProto = 0; 702 if (isa<FunctionNoProtoType>(NewFuncType) && 703 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 704 // The old declaration provided a function prototype, but the 705 // new declaration does not. Merge in the prototype. 706 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 707 OldProto->arg_type_end()); 708 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 709 &ParamTypes[0], ParamTypes.size(), 710 OldProto->isVariadic(), 711 OldProto->getTypeQuals()); 712 New->setType(NewQType); 713 New->setInheritedPrototype(); 714 715 // Synthesize a parameter for each argument type. 716 llvm::SmallVector<ParmVarDecl*, 16> Params; 717 for (FunctionProtoType::arg_type_iterator 718 ParamType = OldProto->arg_type_begin(), 719 ParamEnd = OldProto->arg_type_end(); 720 ParamType != ParamEnd; ++ParamType) { 721 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 722 SourceLocation(), 0, 723 *ParamType, VarDecl::None, 724 0); 725 Param->setImplicit(); 726 Params.push_back(Param); 727 } 728 729 New->setParams(Context, &Params[0], Params.size()); 730 } 731 732 return MergeCompatibleFunctionDecls(New, Old); 733 } 734 735 // GNU C permits a K&R definition to follow a prototype declaration 736 // if the declared types of the parameters in the K&R definition 737 // match the types in the prototype declaration, even when the 738 // promoted types of the parameters from the K&R definition differ 739 // from the types in the prototype. GCC then keeps the types from 740 // the prototype. 741 if (!getLangOptions().CPlusPlus && 742 !getLangOptions().NoExtensions && 743 Old->hasPrototype() && !New->hasPrototype() && 744 New->getType()->getAsFunctionProtoType() && 745 Old->getNumParams() == New->getNumParams()) { 746 llvm::SmallVector<QualType, 16> ArgTypes; 747 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 748 const FunctionProtoType *OldProto 749 = Old->getType()->getAsFunctionProtoType(); 750 const FunctionProtoType *NewProto 751 = New->getType()->getAsFunctionProtoType(); 752 753 // Determine whether this is the GNU C extension. 754 bool GNUCompatible = 755 Context.typesAreCompatible(OldProto->getResultType(), 756 NewProto->getResultType()) && 757 (OldProto->isVariadic() == NewProto->isVariadic()); 758 for (unsigned Idx = 0, End = Old->getNumParams(); 759 GNUCompatible && Idx != End; ++Idx) { 760 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 761 ParmVarDecl *NewParm = New->getParamDecl(Idx); 762 if (Context.typesAreCompatible(OldParm->getType(), 763 NewProto->getArgType(Idx))) { 764 ArgTypes.push_back(NewParm->getType()); 765 } else if (Context.typesAreCompatible(OldParm->getType(), 766 NewParm->getType())) { 767 GNUCompatibleParamWarning Warn 768 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 769 Warnings.push_back(Warn); 770 ArgTypes.push_back(NewParm->getType()); 771 } else 772 GNUCompatible = false; 773 } 774 775 if (GNUCompatible) { 776 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 777 Diag(Warnings[Warn].NewParm->getLocation(), 778 diag::ext_param_promoted_not_compatible_with_prototype) 779 << Warnings[Warn].PromotedType 780 << Warnings[Warn].OldParm->getType(); 781 Diag(Warnings[Warn].OldParm->getLocation(), 782 diag::note_previous_declaration); 783 } 784 785 New->setType(Context.getFunctionType(NewProto->getResultType(), 786 &ArgTypes[0], ArgTypes.size(), 787 NewProto->isVariadic(), 788 NewProto->getTypeQuals())); 789 return MergeCompatibleFunctionDecls(New, Old); 790 } 791 792 // Fall through to diagnose conflicting types. 793 } 794 795 // A function that has already been declared has been redeclared or defined 796 // with a different type- show appropriate diagnostic 797 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 798 // The user has declared a builtin function with an incompatible 799 // signature. 800 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 801 // The function the user is redeclaring is a library-defined 802 // function like 'malloc' or 'printf'. Warn about the 803 // redeclaration, then pretend that we don't know about this 804 // library built-in. 805 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 806 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 807 << Old << Old->getType(); 808 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 809 Old->setInvalidDecl(); 810 return false; 811 } 812 813 PrevDiag = diag::note_previous_builtin_declaration; 814 } 815 816 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 817 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 818 return true; 819} 820 821/// \brief Completes the merge of two function declarations that are 822/// known to be compatible. 823/// 824/// This routine handles the merging of attributes and other 825/// properties of function declarations form the old declaration to 826/// the new declaration, once we know that New is in fact a 827/// redeclaration of Old. 828/// 829/// \returns false 830bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 831 // Merge the attributes 832 MergeAttributes(New, Old, Context); 833 834 // Merge the storage class. 835 New->setStorageClass(Old->getStorageClass()); 836 837 // FIXME: need to implement inline semantics 838 839 // Merge "pure" flag. 840 if (Old->isPure()) 841 New->setPure(); 842 843 // Merge the "deleted" flag. 844 if (Old->isDeleted()) 845 New->setDeleted(); 846 847 if (getLangOptions().CPlusPlus) 848 return MergeCXXFunctionDecl(New, Old); 849 850 return false; 851} 852 853/// MergeVarDecl - We just parsed a variable 'New' which has the same name 854/// and scope as a previous declaration 'Old'. Figure out how to resolve this 855/// situation, merging decls or emitting diagnostics as appropriate. 856/// 857/// Tentative definition rules (C99 6.9.2p2) are checked by 858/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 859/// definitions here, since the initializer hasn't been attached. 860/// 861bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 862 // Verify the old decl was also a variable. 863 VarDecl *Old = dyn_cast<VarDecl>(OldD); 864 if (!Old) { 865 Diag(New->getLocation(), diag::err_redefinition_different_kind) 866 << New->getDeclName(); 867 Diag(OldD->getLocation(), diag::note_previous_definition); 868 return true; 869 } 870 871 MergeAttributes(New, Old, Context); 872 873 // Merge the types 874 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 875 if (MergedT.isNull()) { 876 Diag(New->getLocation(), diag::err_redefinition_different_type) 877 << New->getDeclName(); 878 Diag(Old->getLocation(), diag::note_previous_definition); 879 return true; 880 } 881 New->setType(MergedT); 882 883 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 884 if (New->getStorageClass() == VarDecl::Static && 885 (Old->getStorageClass() == VarDecl::None || 886 Old->getStorageClass() == VarDecl::Extern)) { 887 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 888 Diag(Old->getLocation(), diag::note_previous_definition); 889 return true; 890 } 891 // C99 6.2.2p4: 892 // For an identifier declared with the storage-class specifier 893 // extern in a scope in which a prior declaration of that 894 // identifier is visible,23) if the prior declaration specifies 895 // internal or external linkage, the linkage of the identifier at 896 // the later declaration is the same as the linkage specified at 897 // the prior declaration. If no prior declaration is visible, or 898 // if the prior declaration specifies no linkage, then the 899 // identifier has external linkage. 900 if (New->hasExternalStorage() && Old->hasLinkage()) 901 /* Okay */; 902 else if (New->getStorageClass() != VarDecl::Static && 903 Old->getStorageClass() == VarDecl::Static) { 904 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 905 Diag(Old->getLocation(), diag::note_previous_definition); 906 return true; 907 } 908 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 909 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl() && 910 // Don't complain about out-of-line definitions of static members. 911 !(Old->getLexicalDeclContext()->isRecord() && 912 !New->getLexicalDeclContext()->isRecord())) { 913 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 914 Diag(Old->getLocation(), diag::note_previous_definition); 915 return true; 916 } 917 918 // Keep a chain of previous declarations. 919 New->setPreviousDeclaration(Old); 920 921 return false; 922} 923 924/// CheckParmsForFunctionDef - Check that the parameters of the given 925/// function are appropriate for the definition of a function. This 926/// takes care of any checks that cannot be performed on the 927/// declaration itself, e.g., that the types of each of the function 928/// parameters are complete. 929bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 930 bool HasInvalidParm = false; 931 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 932 ParmVarDecl *Param = FD->getParamDecl(p); 933 934 // C99 6.7.5.3p4: the parameters in a parameter type list in a 935 // function declarator that is part of a function definition of 936 // that function shall not have incomplete type. 937 // 938 // This is also C++ [dcl.fct]p6. 939 if (!Param->isInvalidDecl() && 940 RequireCompleteType(Param->getLocation(), Param->getType(), 941 diag::err_typecheck_decl_incomplete_type)) { 942 Param->setInvalidDecl(); 943 HasInvalidParm = true; 944 } 945 946 // C99 6.9.1p5: If the declarator includes a parameter type list, the 947 // declaration of each parameter shall include an identifier. 948 if (Param->getIdentifier() == 0 && 949 !Param->isImplicit() && 950 !getLangOptions().CPlusPlus) 951 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 952 } 953 954 return HasInvalidParm; 955} 956 957/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 958/// no declarator (e.g. "struct foo;") is parsed. 959Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 960 // FIXME: Error on auto/register at file scope 961 // FIXME: Error on inline/virtual/explicit 962 // FIXME: Error on invalid restrict 963 // FIXME: Warn on useless const/volatile 964 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 965 // FIXME: Warn on useless attributes 966 967 TagDecl *Tag = 0; 968 if (DS.getTypeSpecType() == DeclSpec::TST_class || 969 DS.getTypeSpecType() == DeclSpec::TST_struct || 970 DS.getTypeSpecType() == DeclSpec::TST_union || 971 DS.getTypeSpecType() == DeclSpec::TST_enum) 972 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 973 974 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 975 if (!Record->getDeclName() && Record->isDefinition() && 976 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 977 if (getLangOptions().CPlusPlus || 978 Record->getDeclContext()->isRecord()) 979 return BuildAnonymousStructOrUnion(S, DS, Record); 980 981 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 982 << DS.getSourceRange(); 983 } 984 985 // Microsoft allows unnamed struct/union fields. Don't complain 986 // about them. 987 // FIXME: Should we support Microsoft's extensions in this area? 988 if (Record->getDeclName() && getLangOptions().Microsoft) 989 return DeclPtrTy::make(Tag); 990 } 991 992 if (!DS.isMissingDeclaratorOk() && 993 DS.getTypeSpecType() != DeclSpec::TST_error) { 994 // Warn about typedefs of enums without names, since this is an 995 // extension in both Microsoft an GNU. 996 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 997 Tag && isa<EnumDecl>(Tag)) { 998 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 999 << DS.getSourceRange(); 1000 return DeclPtrTy::make(Tag); 1001 } 1002 1003 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1004 << DS.getSourceRange(); 1005 return DeclPtrTy(); 1006 } 1007 1008 return DeclPtrTy::make(Tag); 1009} 1010 1011/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1012/// anonymous struct or union AnonRecord into the owning context Owner 1013/// and scope S. This routine will be invoked just after we realize 1014/// that an unnamed union or struct is actually an anonymous union or 1015/// struct, e.g., 1016/// 1017/// @code 1018/// union { 1019/// int i; 1020/// float f; 1021/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1022/// // f into the surrounding scope.x 1023/// @endcode 1024/// 1025/// This routine is recursive, injecting the names of nested anonymous 1026/// structs/unions into the owning context and scope as well. 1027bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1028 RecordDecl *AnonRecord) { 1029 bool Invalid = false; 1030 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1031 FEnd = AnonRecord->field_end(Context); 1032 F != FEnd; ++F) { 1033 if ((*F)->getDeclName()) { 1034 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1035 LookupOrdinaryName, true); 1036 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1037 // C++ [class.union]p2: 1038 // The names of the members of an anonymous union shall be 1039 // distinct from the names of any other entity in the 1040 // scope in which the anonymous union is declared. 1041 unsigned diagKind 1042 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1043 : diag::err_anonymous_struct_member_redecl; 1044 Diag((*F)->getLocation(), diagKind) 1045 << (*F)->getDeclName(); 1046 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1047 Invalid = true; 1048 } else { 1049 // C++ [class.union]p2: 1050 // For the purpose of name lookup, after the anonymous union 1051 // definition, the members of the anonymous union are 1052 // considered to have been defined in the scope in which the 1053 // anonymous union is declared. 1054 Owner->makeDeclVisibleInContext(Context, *F); 1055 S->AddDecl(DeclPtrTy::make(*F)); 1056 IdResolver.AddDecl(*F); 1057 } 1058 } else if (const RecordType *InnerRecordType 1059 = (*F)->getType()->getAsRecordType()) { 1060 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1061 if (InnerRecord->isAnonymousStructOrUnion()) 1062 Invalid = Invalid || 1063 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1064 } 1065 } 1066 1067 return Invalid; 1068} 1069 1070/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1071/// anonymous structure or union. Anonymous unions are a C++ feature 1072/// (C++ [class.union]) and a GNU C extension; anonymous structures 1073/// are a GNU C and GNU C++ extension. 1074Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1075 RecordDecl *Record) { 1076 DeclContext *Owner = Record->getDeclContext(); 1077 1078 // Diagnose whether this anonymous struct/union is an extension. 1079 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1080 Diag(Record->getLocation(), diag::ext_anonymous_union); 1081 else if (!Record->isUnion()) 1082 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1083 1084 // C and C++ require different kinds of checks for anonymous 1085 // structs/unions. 1086 bool Invalid = false; 1087 if (getLangOptions().CPlusPlus) { 1088 const char* PrevSpec = 0; 1089 // C++ [class.union]p3: 1090 // Anonymous unions declared in a named namespace or in the 1091 // global namespace shall be declared static. 1092 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1093 (isa<TranslationUnitDecl>(Owner) || 1094 (isa<NamespaceDecl>(Owner) && 1095 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1096 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1097 Invalid = true; 1098 1099 // Recover by adding 'static'. 1100 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1101 } 1102 // C++ [class.union]p3: 1103 // A storage class is not allowed in a declaration of an 1104 // anonymous union in a class scope. 1105 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1106 isa<RecordDecl>(Owner)) { 1107 Diag(DS.getStorageClassSpecLoc(), 1108 diag::err_anonymous_union_with_storage_spec); 1109 Invalid = true; 1110 1111 // Recover by removing the storage specifier. 1112 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1113 PrevSpec); 1114 } 1115 1116 // C++ [class.union]p2: 1117 // The member-specification of an anonymous union shall only 1118 // define non-static data members. [Note: nested types and 1119 // functions cannot be declared within an anonymous union. ] 1120 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1121 MemEnd = Record->decls_end(Context); 1122 Mem != MemEnd; ++Mem) { 1123 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1124 // C++ [class.union]p3: 1125 // An anonymous union shall not have private or protected 1126 // members (clause 11). 1127 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1128 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1129 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1130 Invalid = true; 1131 } 1132 } else if ((*Mem)->isImplicit()) { 1133 // Any implicit members are fine. 1134 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1135 // This is a type that showed up in an 1136 // elaborated-type-specifier inside the anonymous struct or 1137 // union, but which actually declares a type outside of the 1138 // anonymous struct or union. It's okay. 1139 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1140 if (!MemRecord->isAnonymousStructOrUnion() && 1141 MemRecord->getDeclName()) { 1142 // This is a nested type declaration. 1143 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1144 << (int)Record->isUnion(); 1145 Invalid = true; 1146 } 1147 } else { 1148 // We have something that isn't a non-static data 1149 // member. Complain about it. 1150 unsigned DK = diag::err_anonymous_record_bad_member; 1151 if (isa<TypeDecl>(*Mem)) 1152 DK = diag::err_anonymous_record_with_type; 1153 else if (isa<FunctionDecl>(*Mem)) 1154 DK = diag::err_anonymous_record_with_function; 1155 else if (isa<VarDecl>(*Mem)) 1156 DK = diag::err_anonymous_record_with_static; 1157 Diag((*Mem)->getLocation(), DK) 1158 << (int)Record->isUnion(); 1159 Invalid = true; 1160 } 1161 } 1162 } 1163 1164 if (!Record->isUnion() && !Owner->isRecord()) { 1165 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1166 << (int)getLangOptions().CPlusPlus; 1167 Invalid = true; 1168 } 1169 1170 // Create a declaration for this anonymous struct/union. 1171 NamedDecl *Anon = 0; 1172 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1173 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1174 /*IdentifierInfo=*/0, 1175 Context.getTypeDeclType(Record), 1176 /*BitWidth=*/0, /*Mutable=*/false); 1177 Anon->setAccess(AS_public); 1178 if (getLangOptions().CPlusPlus) 1179 FieldCollector->Add(cast<FieldDecl>(Anon)); 1180 } else { 1181 VarDecl::StorageClass SC; 1182 switch (DS.getStorageClassSpec()) { 1183 default: assert(0 && "Unknown storage class!"); 1184 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1185 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1186 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1187 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1188 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1189 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1190 case DeclSpec::SCS_mutable: 1191 // mutable can only appear on non-static class members, so it's always 1192 // an error here 1193 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1194 Invalid = true; 1195 SC = VarDecl::None; 1196 break; 1197 } 1198 1199 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1200 /*IdentifierInfo=*/0, 1201 Context.getTypeDeclType(Record), 1202 SC, DS.getSourceRange().getBegin()); 1203 } 1204 Anon->setImplicit(); 1205 1206 // Add the anonymous struct/union object to the current 1207 // context. We'll be referencing this object when we refer to one of 1208 // its members. 1209 Owner->addDecl(Context, Anon); 1210 1211 // Inject the members of the anonymous struct/union into the owning 1212 // context and into the identifier resolver chain for name lookup 1213 // purposes. 1214 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1215 Invalid = true; 1216 1217 // Mark this as an anonymous struct/union type. Note that we do not 1218 // do this until after we have already checked and injected the 1219 // members of this anonymous struct/union type, because otherwise 1220 // the members could be injected twice: once by DeclContext when it 1221 // builds its lookup table, and once by 1222 // InjectAnonymousStructOrUnionMembers. 1223 Record->setAnonymousStructOrUnion(true); 1224 1225 if (Invalid) 1226 Anon->setInvalidDecl(); 1227 1228 return DeclPtrTy::make(Anon); 1229} 1230 1231 1232/// GetNameForDeclarator - Determine the full declaration name for the 1233/// given Declarator. 1234DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1235 switch (D.getKind()) { 1236 case Declarator::DK_Abstract: 1237 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1238 return DeclarationName(); 1239 1240 case Declarator::DK_Normal: 1241 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1242 return DeclarationName(D.getIdentifier()); 1243 1244 case Declarator::DK_Constructor: { 1245 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1246 Ty = Context.getCanonicalType(Ty); 1247 return Context.DeclarationNames.getCXXConstructorName(Ty); 1248 } 1249 1250 case Declarator::DK_Destructor: { 1251 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1252 Ty = Context.getCanonicalType(Ty); 1253 return Context.DeclarationNames.getCXXDestructorName(Ty); 1254 } 1255 1256 case Declarator::DK_Conversion: { 1257 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1258 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1259 Ty = Context.getCanonicalType(Ty); 1260 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1261 } 1262 1263 case Declarator::DK_Operator: 1264 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1265 return Context.DeclarationNames.getCXXOperatorName( 1266 D.getOverloadedOperator()); 1267 } 1268 1269 assert(false && "Unknown name kind"); 1270 return DeclarationName(); 1271} 1272 1273/// isNearlyMatchingFunction - Determine whether the C++ functions 1274/// Declaration and Definition are "nearly" matching. This heuristic 1275/// is used to improve diagnostics in the case where an out-of-line 1276/// function definition doesn't match any declaration within 1277/// the class or namespace. 1278static bool isNearlyMatchingFunction(ASTContext &Context, 1279 FunctionDecl *Declaration, 1280 FunctionDecl *Definition) { 1281 if (Declaration->param_size() != Definition->param_size()) 1282 return false; 1283 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1284 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1285 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1286 1287 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1288 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1289 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1290 return false; 1291 } 1292 1293 return true; 1294} 1295 1296Sema::DeclPtrTy 1297Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1298 DeclarationName Name = GetNameForDeclarator(D); 1299 1300 // All of these full declarators require an identifier. If it doesn't have 1301 // one, the ParsedFreeStandingDeclSpec action should be used. 1302 if (!Name) { 1303 if (!D.getInvalidType()) // Reject this if we think it is valid. 1304 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1305 diag::err_declarator_need_ident) 1306 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1307 return DeclPtrTy(); 1308 } 1309 1310 // The scope passed in may not be a decl scope. Zip up the scope tree until 1311 // we find one that is. 1312 while ((S->getFlags() & Scope::DeclScope) == 0 || 1313 (S->getFlags() & Scope::TemplateParamScope) != 0) 1314 S = S->getParent(); 1315 1316 DeclContext *DC; 1317 NamedDecl *PrevDecl; 1318 NamedDecl *New; 1319 bool InvalidDecl = false; 1320 1321 QualType R = GetTypeForDeclarator(D, S); 1322 if (R.isNull()) { 1323 InvalidDecl = true; 1324 R = Context.IntTy; 1325 } 1326 1327 // See if this is a redefinition of a variable in the same scope. 1328 if (D.getCXXScopeSpec().isInvalid()) { 1329 DC = CurContext; 1330 PrevDecl = 0; 1331 InvalidDecl = true; 1332 } else if (!D.getCXXScopeSpec().isSet()) { 1333 LookupNameKind NameKind = LookupOrdinaryName; 1334 1335 // If the declaration we're planning to build will be a function 1336 // or object with linkage, then look for another declaration with 1337 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1338 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1339 /* Do nothing*/; 1340 else if (R->isFunctionType()) { 1341 if (CurContext->isFunctionOrMethod()) 1342 NameKind = LookupRedeclarationWithLinkage; 1343 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1344 NameKind = LookupRedeclarationWithLinkage; 1345 1346 DC = CurContext; 1347 PrevDecl = LookupName(S, Name, NameKind, true, 1348 D.getDeclSpec().getStorageClassSpec() != 1349 DeclSpec::SCS_static, 1350 D.getIdentifierLoc()); 1351 } else { // Something like "int foo::x;" 1352 DC = computeDeclContext(D.getCXXScopeSpec()); 1353 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1354 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1355 1356 // C++ 7.3.1.2p2: 1357 // Members (including explicit specializations of templates) of a named 1358 // namespace can also be defined outside that namespace by explicit 1359 // qualification of the name being defined, provided that the entity being 1360 // defined was already declared in the namespace and the definition appears 1361 // after the point of declaration in a namespace that encloses the 1362 // declarations namespace. 1363 // 1364 // Note that we only check the context at this point. We don't yet 1365 // have enough information to make sure that PrevDecl is actually 1366 // the declaration we want to match. For example, given: 1367 // 1368 // class X { 1369 // void f(); 1370 // void f(float); 1371 // }; 1372 // 1373 // void X::f(int) { } // ill-formed 1374 // 1375 // In this case, PrevDecl will point to the overload set 1376 // containing the two f's declared in X, but neither of them 1377 // matches. 1378 1379 // First check whether we named the global scope. 1380 if (isa<TranslationUnitDecl>(DC)) { 1381 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1382 << Name << D.getCXXScopeSpec().getRange(); 1383 } else if (!CurContext->Encloses(DC)) { 1384 // The qualifying scope doesn't enclose the original declaration. 1385 // Emit diagnostic based on current scope. 1386 SourceLocation L = D.getIdentifierLoc(); 1387 SourceRange R = D.getCXXScopeSpec().getRange(); 1388 if (isa<FunctionDecl>(CurContext)) 1389 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1390 else 1391 Diag(L, diag::err_invalid_declarator_scope) 1392 << Name << cast<NamedDecl>(DC) << R; 1393 InvalidDecl = true; 1394 } 1395 } 1396 1397 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1398 // Maybe we will complain about the shadowed template parameter. 1399 InvalidDecl = InvalidDecl 1400 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1401 // Just pretend that we didn't see the previous declaration. 1402 PrevDecl = 0; 1403 } 1404 1405 // In C++, the previous declaration we find might be a tag type 1406 // (class or enum). In this case, the new declaration will hide the 1407 // tag type. Note that this does does not apply if we're declaring a 1408 // typedef (C++ [dcl.typedef]p4). 1409 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1410 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1411 PrevDecl = 0; 1412 1413 bool Redeclaration = false; 1414 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1415 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, 1416 InvalidDecl, Redeclaration); 1417 } else if (R->isFunctionType()) { 1418 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1419 IsFunctionDefinition, InvalidDecl, 1420 Redeclaration); 1421 } else { 1422 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, 1423 InvalidDecl, Redeclaration); 1424 } 1425 1426 if (New == 0) 1427 return DeclPtrTy(); 1428 1429 // If this has an identifier and is not an invalid redeclaration, 1430 // add it to the scope stack. 1431 if (Name && !(Redeclaration && InvalidDecl)) 1432 PushOnScopeChains(New, S); 1433 // If any semantic error occurred, mark the decl as invalid. 1434 if (D.getInvalidType() || InvalidDecl) 1435 New->setInvalidDecl(); 1436 1437 return DeclPtrTy::make(New); 1438} 1439 1440/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1441/// types into constant array types in certain situations which would otherwise 1442/// be errors (for GCC compatibility). 1443static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1444 ASTContext &Context, 1445 bool &SizeIsNegative) { 1446 // This method tries to turn a variable array into a constant 1447 // array even when the size isn't an ICE. This is necessary 1448 // for compatibility with code that depends on gcc's buggy 1449 // constant expression folding, like struct {char x[(int)(char*)2];} 1450 SizeIsNegative = false; 1451 1452 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1453 QualType Pointee = PTy->getPointeeType(); 1454 QualType FixedType = 1455 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1456 if (FixedType.isNull()) return FixedType; 1457 FixedType = Context.getPointerType(FixedType); 1458 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1459 return FixedType; 1460 } 1461 1462 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1463 if (!VLATy) 1464 return QualType(); 1465 // FIXME: We should probably handle this case 1466 if (VLATy->getElementType()->isVariablyModifiedType()) 1467 return QualType(); 1468 1469 Expr::EvalResult EvalResult; 1470 if (!VLATy->getSizeExpr() || 1471 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1472 !EvalResult.Val.isInt()) 1473 return QualType(); 1474 1475 llvm::APSInt &Res = EvalResult.Val.getInt(); 1476 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1477 return Context.getConstantArrayType(VLATy->getElementType(), 1478 Res, ArrayType::Normal, 0); 1479 1480 SizeIsNegative = true; 1481 return QualType(); 1482} 1483 1484/// \brief Register the given locally-scoped external C declaration so 1485/// that it can be found later for redeclarations 1486void 1487Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1488 Scope *S) { 1489 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1490 "Decl is not a locally-scoped decl!"); 1491 // Note that we have a locally-scoped external with this name. 1492 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1493 1494 if (!PrevDecl) 1495 return; 1496 1497 // If there was a previous declaration of this variable, it may be 1498 // in our identifier chain. Update the identifier chain with the new 1499 // declaration. 1500 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1501 // The previous declaration was found on the identifer resolver 1502 // chain, so remove it from its scope. 1503 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1504 S = S->getParent(); 1505 1506 if (S) 1507 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1508 } 1509} 1510 1511/// \brief Diagnose function specifiers on a declaration of an identifier that 1512/// does not identify a function. 1513void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1514 // FIXME: We should probably indicate the identifier in question to avoid 1515 // confusion for constructs like "inline int a(), b;" 1516 if (D.getDeclSpec().isInlineSpecified()) 1517 Diag(D.getDeclSpec().getInlineSpecLoc(), 1518 diag::err_inline_non_function); 1519 1520 if (D.getDeclSpec().isVirtualSpecified()) 1521 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1522 diag::err_virtual_non_function); 1523 1524 if (D.getDeclSpec().isExplicitSpecified()) 1525 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1526 diag::err_explicit_non_function); 1527} 1528 1529NamedDecl* 1530Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1531 QualType R, Decl* PrevDecl, bool& InvalidDecl, 1532 bool &Redeclaration) { 1533 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1534 if (D.getCXXScopeSpec().isSet()) { 1535 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1536 << D.getCXXScopeSpec().getRange(); 1537 InvalidDecl = true; 1538 // Pretend we didn't see the scope specifier. 1539 DC = 0; 1540 } 1541 1542 if (getLangOptions().CPlusPlus) { 1543 // Check that there are no default arguments (C++ only). 1544 CheckExtraCXXDefaultArguments(D); 1545 } 1546 1547 DiagnoseFunctionSpecifiers(D); 1548 1549 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1550 if (!NewTD) return 0; 1551 1552 // Handle attributes prior to checking for duplicates in MergeVarDecl 1553 ProcessDeclAttributes(NewTD, D); 1554 // Merge the decl with the existing one if appropriate. If the decl is 1555 // in an outer scope, it isn't the same thing. 1556 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1557 Redeclaration = true; 1558 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1559 InvalidDecl = true; 1560 } 1561 1562 if (S->getFnParent() == 0) { 1563 QualType T = NewTD->getUnderlyingType(); 1564 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1565 // then it shall have block scope. 1566 if (T->isVariablyModifiedType()) { 1567 bool SizeIsNegative; 1568 QualType FixedTy = 1569 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1570 if (!FixedTy.isNull()) { 1571 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1572 NewTD->setUnderlyingType(FixedTy); 1573 } else { 1574 if (SizeIsNegative) 1575 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1576 else if (T->isVariableArrayType()) 1577 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1578 else 1579 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1580 InvalidDecl = true; 1581 } 1582 } 1583 } 1584 return NewTD; 1585} 1586 1587/// \brief Determines whether the given declaration is an out-of-scope 1588/// previous declaration. 1589/// 1590/// This routine should be invoked when name lookup has found a 1591/// previous declaration (PrevDecl) that is not in the scope where a 1592/// new declaration by the same name is being introduced. If the new 1593/// declaration occurs in a local scope, previous declarations with 1594/// linkage may still be considered previous declarations (C99 1595/// 6.2.2p4-5, C++ [basic.link]p6). 1596/// 1597/// \param PrevDecl the previous declaration found by name 1598/// lookup 1599/// 1600/// \param DC the context in which the new declaration is being 1601/// declared. 1602/// 1603/// \returns true if PrevDecl is an out-of-scope previous declaration 1604/// for a new delcaration with the same name. 1605static bool 1606isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1607 ASTContext &Context) { 1608 if (!PrevDecl) 1609 return 0; 1610 1611 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1612 // case we need to check each of the overloaded functions. 1613 if (!PrevDecl->hasLinkage()) 1614 return false; 1615 1616 if (Context.getLangOptions().CPlusPlus) { 1617 // C++ [basic.link]p6: 1618 // If there is a visible declaration of an entity with linkage 1619 // having the same name and type, ignoring entities declared 1620 // outside the innermost enclosing namespace scope, the block 1621 // scope declaration declares that same entity and receives the 1622 // linkage of the previous declaration. 1623 DeclContext *OuterContext = DC->getLookupContext(); 1624 if (!OuterContext->isFunctionOrMethod()) 1625 // This rule only applies to block-scope declarations. 1626 return false; 1627 else { 1628 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1629 if (PrevOuterContext->isRecord()) 1630 // We found a member function: ignore it. 1631 return false; 1632 else { 1633 // Find the innermost enclosing namespace for the new and 1634 // previous declarations. 1635 while (!OuterContext->isFileContext()) 1636 OuterContext = OuterContext->getParent(); 1637 while (!PrevOuterContext->isFileContext()) 1638 PrevOuterContext = PrevOuterContext->getParent(); 1639 1640 // The previous declaration is in a different namespace, so it 1641 // isn't the same function. 1642 if (OuterContext->getPrimaryContext() != 1643 PrevOuterContext->getPrimaryContext()) 1644 return false; 1645 } 1646 } 1647 } 1648 1649 return true; 1650} 1651 1652NamedDecl* 1653Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1654 QualType R,NamedDecl* PrevDecl, bool& InvalidDecl, 1655 bool &Redeclaration) { 1656 DeclarationName Name = GetNameForDeclarator(D); 1657 1658 // Check that there are no default arguments (C++ only). 1659 if (getLangOptions().CPlusPlus) 1660 CheckExtraCXXDefaultArguments(D); 1661 1662 VarDecl *NewVD; 1663 VarDecl::StorageClass SC; 1664 switch (D.getDeclSpec().getStorageClassSpec()) { 1665 default: assert(0 && "Unknown storage class!"); 1666 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1667 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1668 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1669 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1670 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1671 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1672 case DeclSpec::SCS_mutable: 1673 // mutable can only appear on non-static class members, so it's always 1674 // an error here 1675 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1676 InvalidDecl = true; 1677 SC = VarDecl::None; 1678 break; 1679 } 1680 1681 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1682 if (!II) { 1683 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1684 << Name.getAsString(); 1685 return 0; 1686 } 1687 1688 DiagnoseFunctionSpecifiers(D); 1689 1690 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1691 if (!DC->isRecord() && S->getFnParent() == 0) { 1692 // C99 6.9p2: The storage-class specifiers auto and register shall not 1693 // appear in the declaration specifiers in an external declaration. 1694 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1695 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1696 InvalidDecl = true; 1697 } 1698 } 1699 if (DC->isRecord() && !CurContext->isRecord()) { 1700 // This is an out-of-line definition of a static data member. 1701 if (SC == VarDecl::Static) { 1702 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1703 diag::err_static_out_of_line) 1704 << CodeModificationHint::CreateRemoval( 1705 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1706 } else if (SC == VarDecl::None) 1707 SC = VarDecl::Static; 1708 } 1709 1710 // The variable can not 1711 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1712 II, R, SC, 1713 // FIXME: Move to DeclGroup... 1714 D.getDeclSpec().getSourceRange().getBegin()); 1715 NewVD->setThreadSpecified(ThreadSpecified); 1716 1717 // Set the lexical context. If the declarator has a C++ scope specifier, the 1718 // lexical context will be different from the semantic context. 1719 NewVD->setLexicalDeclContext(CurContext); 1720 1721 // Handle attributes prior to checking for duplicates in MergeVarDecl 1722 ProcessDeclAttributes(NewVD, D); 1723 1724 // Handle GNU asm-label extension (encoded as an attribute). 1725 if (Expr *E = (Expr*) D.getAsmLabel()) { 1726 // The parser guarantees this is a string. 1727 StringLiteral *SE = cast<StringLiteral>(E); 1728 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1729 SE->getByteLength()))); 1730 } 1731 1732 // If name lookup finds a previous declaration that is not in the 1733 // same scope as the new declaration, this may still be an 1734 // acceptable redeclaration. 1735 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1736 !(NewVD->hasLinkage() && 1737 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1738 PrevDecl = 0; 1739 1740 // Merge the decl with the existing one if appropriate. 1741 if (PrevDecl) { 1742 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1743 // The user tried to define a non-static data member 1744 // out-of-line (C++ [dcl.meaning]p1). 1745 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1746 << D.getCXXScopeSpec().getRange(); 1747 PrevDecl = 0; 1748 InvalidDecl = true; 1749 } 1750 } else if (D.getCXXScopeSpec().isSet()) { 1751 // No previous declaration in the qualifying scope. 1752 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1753 << Name << D.getCXXScopeSpec().getRange(); 1754 InvalidDecl = true; 1755 } 1756 1757 if (CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration)) 1758 InvalidDecl = true; 1759 1760 // If this is a locally-scoped extern C variable, update the map of 1761 // such variables. 1762 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1763 !InvalidDecl) 1764 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1765 1766 return NewVD; 1767} 1768 1769/// \brief Perform semantic checking on a newly-created variable 1770/// declaration. 1771/// 1772/// This routine performs all of the type-checking required for a 1773/// variable declaration once it has been build. It is used both to 1774/// check variables after they have been parsed and their declarators 1775/// have been translated into a declaration, and to check 1776/// 1777/// \returns true if an error was encountered, false otherwise. 1778bool Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1779 bool &Redeclaration) { 1780 bool Invalid = false; 1781 1782 QualType T = NewVD->getType(); 1783 1784 if (T->isObjCInterfaceType()) { 1785 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1786 Invalid = true; 1787 } 1788 1789 // The variable can not have an abstract class type. 1790 if (RequireNonAbstractType(NewVD->getLocation(), T, 1791 diag::err_abstract_type_in_decl, 1792 AbstractVariableType)) 1793 Invalid = true; 1794 1795 // Emit an error if an address space was applied to decl with local storage. 1796 // This includes arrays of objects with address space qualifiers, but not 1797 // automatic variables that point to other address spaces. 1798 // ISO/IEC TR 18037 S5.1.2 1799 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1800 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1801 Invalid = true; 1802 } 1803 1804 if (NewVD->hasLocalStorage() && T.isObjCGCWeak()) 1805 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1806 1807 bool isIllegalVLA = T->isVariableArrayType() && NewVD->hasGlobalStorage(); 1808 bool isIllegalVM = T->isVariablyModifiedType() && NewVD->hasLinkage(); 1809 if (isIllegalVLA || isIllegalVM) { 1810 bool SizeIsNegative; 1811 QualType FixedTy = 1812 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1813 if (!FixedTy.isNull()) { 1814 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1815 NewVD->setType(FixedTy); 1816 } else if (T->isVariableArrayType()) { 1817 Invalid = true; 1818 1819 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1820 // FIXME: This won't give the correct result for 1821 // int a[10][n]; 1822 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1823 1824 if (NewVD->isFileVarDecl()) 1825 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1826 << SizeRange; 1827 else if (NewVD->getStorageClass() == VarDecl::Static) 1828 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1829 << SizeRange; 1830 else 1831 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1832 << SizeRange; 1833 } else { 1834 Invalid = true; 1835 1836 if (NewVD->isFileVarDecl()) 1837 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1838 else 1839 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1840 } 1841 } 1842 1843 if (!PrevDecl && NewVD->isExternC(Context)) { 1844 // Since we did not find anything by this name and we're declaring 1845 // an extern "C" variable, look for a non-visible extern "C" 1846 // declaration with the same name. 1847 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1848 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1849 if (Pos != LocallyScopedExternalDecls.end()) 1850 PrevDecl = Pos->second; 1851 } 1852 1853 if (!Invalid && T->isVoidType() && !NewVD->hasExternalStorage()) { 1854 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1855 << T; 1856 Invalid = true; 1857 } 1858 1859 if (PrevDecl) { 1860 Redeclaration = true; 1861 if (MergeVarDecl(NewVD, PrevDecl)) 1862 Invalid = true; 1863 } 1864 1865 return NewVD->isInvalidDecl() || Invalid; 1866} 1867 1868NamedDecl* 1869Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1870 QualType R, NamedDecl* PrevDecl, 1871 bool IsFunctionDefinition, 1872 bool& InvalidDecl, bool &Redeclaration) { 1873 assert(R.getTypePtr()->isFunctionType()); 1874 1875 DeclarationName Name = GetNameForDeclarator(D); 1876 FunctionDecl::StorageClass SC = FunctionDecl::None; 1877 switch (D.getDeclSpec().getStorageClassSpec()) { 1878 default: assert(0 && "Unknown storage class!"); 1879 case DeclSpec::SCS_auto: 1880 case DeclSpec::SCS_register: 1881 case DeclSpec::SCS_mutable: 1882 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1883 diag::err_typecheck_sclass_func); 1884 InvalidDecl = true; 1885 break; 1886 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1887 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1888 case DeclSpec::SCS_static: { 1889 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1890 // C99 6.7.1p5: 1891 // The declaration of an identifier for a function that has 1892 // block scope shall have no explicit storage-class specifier 1893 // other than extern 1894 // See also (C++ [dcl.stc]p4). 1895 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1896 diag::err_static_block_func); 1897 SC = FunctionDecl::None; 1898 } else 1899 SC = FunctionDecl::Static; 1900 break; 1901 } 1902 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1903 } 1904 1905 bool isInline = D.getDeclSpec().isInlineSpecified(); 1906 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1907 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1908 1909 // Check that the return type is not an abstract class type. 1910 // For record types, this is done by the AbstractClassUsageDiagnoser once 1911 // the class has been completely parsed. 1912 if (!DC->isRecord() && 1913 RequireNonAbstractType(D.getIdentifierLoc(), 1914 R->getAsFunctionType()->getResultType(), 1915 diag::err_abstract_type_in_decl, 1916 AbstractReturnType)) 1917 InvalidDecl = true; 1918 1919 // Do not allow returning a objc interface by-value. 1920 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1921 Diag(D.getIdentifierLoc(), 1922 diag::err_object_cannot_be_passed_returned_by_value) << 0 1923 << R->getAsFunctionType()->getResultType(); 1924 InvalidDecl = true; 1925 } 1926 1927 bool isVirtualOkay = false; 1928 FunctionDecl *NewFD; 1929 if (D.getKind() == Declarator::DK_Constructor) { 1930 // This is a C++ constructor declaration. 1931 assert(DC->isRecord() && 1932 "Constructors can only be declared in a member context"); 1933 1934 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1935 1936 // Create the new declaration 1937 NewFD = CXXConstructorDecl::Create(Context, 1938 cast<CXXRecordDecl>(DC), 1939 D.getIdentifierLoc(), Name, R, 1940 isExplicit, isInline, 1941 /*isImplicitlyDeclared=*/false); 1942 1943 if (InvalidDecl) 1944 NewFD->setInvalidDecl(); 1945 } else if (D.getKind() == Declarator::DK_Destructor) { 1946 // This is a C++ destructor declaration. 1947 if (DC->isRecord()) { 1948 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1949 1950 NewFD = CXXDestructorDecl::Create(Context, 1951 cast<CXXRecordDecl>(DC), 1952 D.getIdentifierLoc(), Name, R, 1953 isInline, 1954 /*isImplicitlyDeclared=*/false); 1955 1956 if (InvalidDecl) 1957 NewFD->setInvalidDecl(); 1958 1959 isVirtualOkay = true; 1960 } else { 1961 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1962 1963 // Create a FunctionDecl to satisfy the function definition parsing 1964 // code path. 1965 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1966 Name, R, SC, isInline, 1967 /*hasPrototype=*/true, 1968 // FIXME: Move to DeclGroup... 1969 D.getDeclSpec().getSourceRange().getBegin()); 1970 InvalidDecl = true; 1971 NewFD->setInvalidDecl(); 1972 } 1973 } else if (D.getKind() == Declarator::DK_Conversion) { 1974 if (!DC->isRecord()) { 1975 Diag(D.getIdentifierLoc(), 1976 diag::err_conv_function_not_member); 1977 return 0; 1978 } else { 1979 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1980 1981 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1982 D.getIdentifierLoc(), Name, R, 1983 isInline, isExplicit); 1984 1985 if (InvalidDecl) 1986 NewFD->setInvalidDecl(); 1987 1988 isVirtualOkay = true; 1989 } 1990 } else if (DC->isRecord()) { 1991 // This is a C++ method declaration. 1992 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1993 D.getIdentifierLoc(), Name, R, 1994 (SC == FunctionDecl::Static), isInline); 1995 1996 isVirtualOkay = (SC != FunctionDecl::Static); 1997 } else { 1998 // Determine whether the function was written with a 1999 // prototype. This true when: 2000 // - we're in C++ (where every function has a prototype), 2001 // - there is a prototype in the declarator, or 2002 // - the type R of the function is some kind of typedef or other reference 2003 // to a type name (which eventually refers to a function type). 2004 bool HasPrototype = 2005 getLangOptions().CPlusPlus || 2006 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2007 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2008 2009 NewFD = FunctionDecl::Create(Context, DC, 2010 D.getIdentifierLoc(), 2011 Name, R, SC, isInline, HasPrototype, 2012 // FIXME: Move to DeclGroup... 2013 D.getDeclSpec().getSourceRange().getBegin()); 2014 } 2015 2016 // Set the lexical context. If the declarator has a C++ 2017 // scope specifier, the lexical context will be different 2018 // from the semantic context. 2019 NewFD->setLexicalDeclContext(CurContext); 2020 2021 // C++ [dcl.fct.spec]p5: 2022 // The virtual specifier shall only be used in declarations of 2023 // nonstatic class member functions that appear within a 2024 // member-specification of a class declaration; see 10.3. 2025 // 2026 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2027 // function is also virtual if it overrides an already virtual 2028 // function. This is important to do here because it's part of the 2029 // declaration. 2030 if (isVirtual && !InvalidDecl) { 2031 if (!isVirtualOkay) { 2032 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2033 diag::err_virtual_non_function); 2034 } else if (!CurContext->isRecord()) { 2035 // 'virtual' was specified outside of the class. 2036 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2037 << CodeModificationHint::CreateRemoval( 2038 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2039 } else { 2040 // Okay: Add virtual to the method. 2041 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2042 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2043 CurClass->setAggregate(false); 2044 CurClass->setPOD(false); 2045 CurClass->setPolymorphic(true); 2046 } 2047 } 2048 2049 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2050 !CurContext->isRecord()) { 2051 // C++ [class.static]p1: 2052 // A data or function member of a class may be declared static 2053 // in a class definition, in which case it is a static member of 2054 // the class. 2055 2056 // Complain about the 'static' specifier if it's on an out-of-line 2057 // member function definition. 2058 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2059 diag::err_static_out_of_line) 2060 << CodeModificationHint::CreateRemoval( 2061 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2062 } 2063 2064 // Handle GNU asm-label extension (encoded as an attribute). 2065 if (Expr *E = (Expr*) D.getAsmLabel()) { 2066 // The parser guarantees this is a string. 2067 StringLiteral *SE = cast<StringLiteral>(E); 2068 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2069 SE->getByteLength()))); 2070 } 2071 2072 // Copy the parameter declarations from the declarator D to 2073 // the function declaration NewFD, if they are available. 2074 if (D.getNumTypeObjects() > 0) { 2075 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2076 2077 // Create Decl objects for each parameter, adding them to the 2078 // FunctionDecl. 2079 llvm::SmallVector<ParmVarDecl*, 16> Params; 2080 2081 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2082 // function that takes no arguments, not a function that takes a 2083 // single void argument. 2084 // We let through "const void" here because Sema::GetTypeForDeclarator 2085 // already checks for that case. 2086 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2087 FTI.ArgInfo[0].Param && 2088 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2089 // empty arg list, don't push any params. 2090 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2091 2092 // In C++, the empty parameter-type-list must be spelled "void"; a 2093 // typedef of void is not permitted. 2094 if (getLangOptions().CPlusPlus && 2095 Param->getType().getUnqualifiedType() != Context.VoidTy) { 2096 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2097 } 2098 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2099 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2100 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2101 } 2102 2103 NewFD->setParams(Context, &Params[0], Params.size()); 2104 } else if (R->getAsTypedefType()) { 2105 // When we're declaring a function with a typedef, as in the 2106 // following example, we'll need to synthesize (unnamed) 2107 // parameters for use in the declaration. 2108 // 2109 // @code 2110 // typedef void fn(int); 2111 // fn f; 2112 // @endcode 2113 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 2114 if (!FT) { 2115 // This is a typedef of a function with no prototype, so we 2116 // don't need to do anything. 2117 } else if ((FT->getNumArgs() == 0) || 2118 (FT->getNumArgs() == 1 && !FT->isVariadic() && 2119 FT->getArgType(0)->isVoidType())) { 2120 // This is a zero-argument function. We don't need to do anything. 2121 } else { 2122 // Synthesize a parameter for each argument type. 2123 llvm::SmallVector<ParmVarDecl*, 16> Params; 2124 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 2125 ArgType != FT->arg_type_end(); ++ArgType) { 2126 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2127 SourceLocation(), 0, 2128 *ArgType, VarDecl::None, 2129 0); 2130 Param->setImplicit(); 2131 Params.push_back(Param); 2132 } 2133 2134 NewFD->setParams(Context, &Params[0], Params.size()); 2135 } 2136 } 2137 2138 // If name lookup finds a previous declaration that is not in the 2139 // same scope as the new declaration, this may still be an 2140 // acceptable redeclaration. 2141 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2142 !(NewFD->hasLinkage() && 2143 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2144 PrevDecl = 0; 2145 2146 // Perform semantic checking on the function declaration. 2147 bool OverloadableAttrRequired = false; // FIXME: HACK! 2148 if (CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2149 /*FIXME:*/OverloadableAttrRequired)) 2150 InvalidDecl = true; 2151 2152 if (D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2153 // An out-of-line member function declaration must also be a 2154 // definition (C++ [dcl.meaning]p1). 2155 if (!IsFunctionDefinition) { 2156 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2157 << D.getCXXScopeSpec().getRange(); 2158 InvalidDecl = true; 2159 } else if (!Redeclaration) { 2160 // The user tried to provide an out-of-line definition for a 2161 // function that is a member of a class or namespace, but there 2162 // was no such member function declared (C++ [class.mfct]p2, 2163 // C++ [namespace.memdef]p2). For example: 2164 // 2165 // class X { 2166 // void f() const; 2167 // }; 2168 // 2169 // void X::f() { } // ill-formed 2170 // 2171 // Complain about this problem, and attempt to suggest close 2172 // matches (e.g., those that differ only in cv-qualifiers and 2173 // whether the parameter types are references). 2174 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2175 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2176 InvalidDecl = true; 2177 2178 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2179 true); 2180 assert(!Prev.isAmbiguous() && 2181 "Cannot have an ambiguity in previous-declaration lookup"); 2182 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2183 Func != FuncEnd; ++Func) { 2184 if (isa<FunctionDecl>(*Func) && 2185 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2186 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2187 } 2188 2189 PrevDecl = 0; 2190 } 2191 } 2192 2193 // Handle attributes. We need to have merged decls when handling attributes 2194 // (for example to check for conflicts, etc). 2195 // FIXME: This needs to happen before we merge declarations. Then, 2196 // let attribute merging cope with attribute conflicts. 2197 ProcessDeclAttributes(NewFD, D); 2198 AddKnownFunctionAttributes(NewFD); 2199 2200 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2201 // If a function name is overloadable in C, then every function 2202 // with that name must be marked "overloadable". 2203 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2204 << Redeclaration << NewFD; 2205 if (PrevDecl) 2206 Diag(PrevDecl->getLocation(), 2207 diag::note_attribute_overloadable_prev_overload); 2208 NewFD->addAttr(::new (Context) OverloadableAttr()); 2209 } 2210 2211 // If this is a locally-scoped extern C function, update the 2212 // map of such names. 2213 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2214 && !InvalidDecl) 2215 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2216 2217 return NewFD; 2218} 2219 2220/// \brief Perform semantic checking of a new function declaration. 2221/// 2222/// Performs semantic analysis of the new function declaration 2223/// NewFD. This routine performs all semantic checking that does not 2224/// require the actual declarator involved in the declaration, and is 2225/// used both for the declaration of functions as they are parsed 2226/// (called via ActOnDeclarator) and for the declaration of functions 2227/// that have been instantiated via C++ template instantiation (called 2228/// via InstantiateDecl). 2229/// 2230/// \returns true if there was an error, false otherwise. 2231bool Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2232 bool &Redeclaration, 2233 bool &OverloadableAttrRequired) { 2234 bool InvalidDecl = false; 2235 2236 // Semantic checking for this function declaration (in isolation). 2237 if (getLangOptions().CPlusPlus) { 2238 // C++-specific checks. 2239 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 2240 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 2241 else if (isa<CXXDestructorDecl>(NewFD)) { 2242 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2243 Record->setUserDeclaredDestructor(true); 2244 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2245 // user-defined destructor. 2246 Record->setPOD(false); 2247 } else if (CXXConversionDecl *Conversion 2248 = dyn_cast<CXXConversionDecl>(NewFD)) 2249 ActOnConversionDeclarator(Conversion); 2250 2251 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2252 if (NewFD->isOverloadedOperator() && 2253 CheckOverloadedOperatorDeclaration(NewFD)) 2254 InvalidDecl = true; 2255 } 2256 2257 // Check for a previous declaration of this name. 2258 if (!PrevDecl && NewFD->isExternC(Context)) { 2259 // Since we did not find anything by this name and we're declaring 2260 // an extern "C" function, look for a non-visible extern "C" 2261 // declaration with the same name. 2262 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2263 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2264 if (Pos != LocallyScopedExternalDecls.end()) 2265 PrevDecl = Pos->second; 2266 } 2267 2268 // Merge or overload the declaration with an existing declaration of 2269 // the same name, if appropriate. 2270 if (PrevDecl) { 2271 // Determine whether NewFD is an overload of PrevDecl or 2272 // a declaration that requires merging. If it's an overload, 2273 // there's no more work to do here; we'll just add the new 2274 // function to the scope. 2275 OverloadedFunctionDecl::function_iterator MatchedDecl; 2276 2277 if (!getLangOptions().CPlusPlus && 2278 AllowOverloadingOfFunction(PrevDecl, Context)) { 2279 OverloadableAttrRequired = true; 2280 2281 // Functions marked "overloadable" must have a prototype (that 2282 // we can't get through declaration merging). 2283 if (!NewFD->getType()->getAsFunctionProtoType()) { 2284 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2285 << NewFD; 2286 InvalidDecl = true; 2287 Redeclaration = true; 2288 2289 // Turn this into a variadic function with no parameters. 2290 QualType R = Context.getFunctionType( 2291 NewFD->getType()->getAsFunctionType()->getResultType(), 2292 0, 0, true, 0); 2293 NewFD->setType(R); 2294 } 2295 } 2296 2297 if (PrevDecl && 2298 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2299 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2300 Redeclaration = true; 2301 Decl *OldDecl = PrevDecl; 2302 2303 // If PrevDecl was an overloaded function, extract the 2304 // FunctionDecl that matched. 2305 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2306 OldDecl = *MatchedDecl; 2307 2308 // NewFD and OldDecl represent declarations that need to be 2309 // merged. 2310 if (MergeFunctionDecl(NewFD, OldDecl)) 2311 InvalidDecl = true; 2312 2313 if (!InvalidDecl) 2314 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2315 } 2316 } 2317 2318 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) { 2319 // In C++, check default arguments now that we have merged decls. Unless 2320 // the lexical context is the class, because in this case this is done 2321 // during delayed parsing anyway. 2322 CheckCXXDefaultArguments(NewFD); 2323 } 2324 2325 return InvalidDecl || NewFD->isInvalidDecl(); 2326} 2327 2328bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2329 // FIXME: Need strict checking. In C89, we need to check for 2330 // any assignment, increment, decrement, function-calls, or 2331 // commas outside of a sizeof. In C99, it's the same list, 2332 // except that the aforementioned are allowed in unevaluated 2333 // expressions. Everything else falls under the 2334 // "may accept other forms of constant expressions" exception. 2335 // (We never end up here for C++, so the constant expression 2336 // rules there don't matter.) 2337 if (Init->isConstantInitializer(Context)) 2338 return false; 2339 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2340 << Init->getSourceRange(); 2341 return true; 2342} 2343 2344void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2345 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2346} 2347 2348/// AddInitializerToDecl - Adds the initializer Init to the 2349/// declaration dcl. If DirectInit is true, this is C++ direct 2350/// initialization rather than copy initialization. 2351void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2352 Decl *RealDecl = dcl.getAs<Decl>(); 2353 // If there is no declaration, there was an error parsing it. Just ignore 2354 // the initializer. 2355 if (RealDecl == 0) 2356 return; 2357 2358 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2359 // With declarators parsed the way they are, the parser cannot 2360 // distinguish between a normal initializer and a pure-specifier. 2361 // Thus this grotesque test. 2362 IntegerLiteral *IL; 2363 Expr *Init = static_cast<Expr *>(init.get()); 2364 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2365 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2366 if (Method->isVirtual()) { 2367 Method->setPure(); 2368 2369 // A class is abstract if at least one function is pure virtual. 2370 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2371 } else if (!Method->isInvalidDecl()) { 2372 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2373 << Method->getDeclName() << Init->getSourceRange(); 2374 Method->setInvalidDecl(); 2375 } 2376 } else { 2377 Diag(Method->getLocation(), diag::err_member_function_initialization) 2378 << Method->getDeclName() << Init->getSourceRange(); 2379 Method->setInvalidDecl(); 2380 } 2381 return; 2382 } 2383 2384 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2385 if (!VDecl) { 2386 if (getLangOptions().CPlusPlus && 2387 RealDecl->getLexicalDeclContext()->isRecord() && 2388 isa<NamedDecl>(RealDecl)) 2389 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2390 << cast<NamedDecl>(RealDecl)->getDeclName(); 2391 else 2392 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2393 RealDecl->setInvalidDecl(); 2394 return; 2395 } 2396 2397 const VarDecl *Def = 0; 2398 if (VDecl->getDefinition(Def)) { 2399 Diag(VDecl->getLocation(), diag::err_redefinition) 2400 << VDecl->getDeclName(); 2401 Diag(Def->getLocation(), diag::note_previous_definition); 2402 VDecl->setInvalidDecl(); 2403 return; 2404 } 2405 2406 // Take ownership of the expression, now that we're sure we have somewhere 2407 // to put it. 2408 Expr *Init = static_cast<Expr *>(init.release()); 2409 assert(Init && "missing initializer"); 2410 2411 // Get the decls type and save a reference for later, since 2412 // CheckInitializerTypes may change it. 2413 QualType DclT = VDecl->getType(), SavT = DclT; 2414 if (VDecl->isBlockVarDecl()) { 2415 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2416 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2417 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2418 VDecl->setInvalidDecl(); 2419 } else if (!VDecl->isInvalidDecl()) { 2420 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2421 VDecl->getDeclName(), DirectInit)) 2422 VDecl->setInvalidDecl(); 2423 2424 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2425 // Don't check invalid declarations to avoid emitting useless diagnostics. 2426 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2427 if (SC == VarDecl::Static) // C99 6.7.8p4. 2428 CheckForConstantInitializer(Init, DclT); 2429 } 2430 } 2431 } else if (VDecl->isStaticDataMember() && 2432 VDecl->getLexicalDeclContext()->isRecord()) { 2433 // This is an in-class initialization for a static data member, e.g., 2434 // 2435 // struct S { 2436 // static const int value = 17; 2437 // }; 2438 2439 // Attach the initializer 2440 VDecl->setInit(Init); 2441 2442 // C++ [class.mem]p4: 2443 // A member-declarator can contain a constant-initializer only 2444 // if it declares a static member (9.4) of const integral or 2445 // const enumeration type, see 9.4.2. 2446 QualType T = VDecl->getType(); 2447 if (!T->isDependentType() && 2448 (!Context.getCanonicalType(T).isConstQualified() || 2449 !T->isIntegralType())) { 2450 Diag(VDecl->getLocation(), diag::err_member_initialization) 2451 << VDecl->getDeclName() << Init->getSourceRange(); 2452 VDecl->setInvalidDecl(); 2453 } else { 2454 // C++ [class.static.data]p4: 2455 // If a static data member is of const integral or const 2456 // enumeration type, its declaration in the class definition 2457 // can specify a constant-initializer which shall be an 2458 // integral constant expression (5.19). 2459 if (!Init->isTypeDependent() && 2460 !Init->getType()->isIntegralType()) { 2461 // We have a non-dependent, non-integral or enumeration type. 2462 Diag(Init->getSourceRange().getBegin(), 2463 diag::err_in_class_initializer_non_integral_type) 2464 << Init->getType() << Init->getSourceRange(); 2465 VDecl->setInvalidDecl(); 2466 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2467 // Check whether the expression is a constant expression. 2468 llvm::APSInt Value; 2469 SourceLocation Loc; 2470 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2471 Diag(Loc, diag::err_in_class_initializer_non_constant) 2472 << Init->getSourceRange(); 2473 VDecl->setInvalidDecl(); 2474 } else if (!VDecl->getType()->isDependentType()) 2475 ImpCastExprToType(Init, VDecl->getType()); 2476 } 2477 } 2478 } else if (VDecl->isFileVarDecl()) { 2479 if (VDecl->getStorageClass() == VarDecl::Extern) 2480 Diag(VDecl->getLocation(), diag::warn_extern_init); 2481 if (!VDecl->isInvalidDecl()) 2482 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2483 VDecl->getDeclName(), DirectInit)) 2484 VDecl->setInvalidDecl(); 2485 2486 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2487 // Don't check invalid declarations to avoid emitting useless diagnostics. 2488 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2489 // C99 6.7.8p4. All file scoped initializers need to be constant. 2490 CheckForConstantInitializer(Init, DclT); 2491 } 2492 } 2493 // If the type changed, it means we had an incomplete type that was 2494 // completed by the initializer. For example: 2495 // int ary[] = { 1, 3, 5 }; 2496 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2497 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2498 VDecl->setType(DclT); 2499 Init->setType(DclT); 2500 } 2501 2502 // Attach the initializer to the decl. 2503 VDecl->setInit(Init); 2504 return; 2505} 2506 2507void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2508 Decl *RealDecl = dcl.getAs<Decl>(); 2509 2510 // If there is no declaration, there was an error parsing it. Just ignore it. 2511 if (RealDecl == 0) 2512 return; 2513 2514 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2515 QualType Type = Var->getType(); 2516 // C++ [dcl.init.ref]p3: 2517 // The initializer can be omitted for a reference only in a 2518 // parameter declaration (8.3.5), in the declaration of a 2519 // function return type, in the declaration of a class member 2520 // within its class declaration (9.2), and where the extern 2521 // specifier is explicitly used. 2522 if (Type->isReferenceType() && 2523 Var->getStorageClass() != VarDecl::Extern && 2524 Var->getStorageClass() != VarDecl::PrivateExtern) { 2525 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2526 << Var->getDeclName() 2527 << SourceRange(Var->getLocation(), Var->getLocation()); 2528 Var->setInvalidDecl(); 2529 return; 2530 } 2531 2532 // C++ [dcl.init]p9: 2533 // 2534 // If no initializer is specified for an object, and the object 2535 // is of (possibly cv-qualified) non-POD class type (or array 2536 // thereof), the object shall be default-initialized; if the 2537 // object is of const-qualified type, the underlying class type 2538 // shall have a user-declared default constructor. 2539 if (getLangOptions().CPlusPlus) { 2540 QualType InitType = Type; 2541 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2542 InitType = Array->getElementType(); 2543 if (Var->getStorageClass() != VarDecl::Extern && 2544 Var->getStorageClass() != VarDecl::PrivateExtern && 2545 InitType->isRecordType()) { 2546 const CXXConstructorDecl *Constructor = 0; 2547 if (!RequireCompleteType(Var->getLocation(), InitType, 2548 diag::err_invalid_incomplete_type_use)) 2549 Constructor 2550 = PerformInitializationByConstructor(InitType, 0, 0, 2551 Var->getLocation(), 2552 SourceRange(Var->getLocation(), 2553 Var->getLocation()), 2554 Var->getDeclName(), 2555 IK_Default); 2556 if (!Constructor) 2557 Var->setInvalidDecl(); 2558 } 2559 } 2560 2561#if 0 2562 // FIXME: Temporarily disabled because we are not properly parsing 2563 // linkage specifications on declarations, e.g., 2564 // 2565 // extern "C" const CGPoint CGPointerZero; 2566 // 2567 // C++ [dcl.init]p9: 2568 // 2569 // If no initializer is specified for an object, and the 2570 // object is of (possibly cv-qualified) non-POD class type (or 2571 // array thereof), the object shall be default-initialized; if 2572 // the object is of const-qualified type, the underlying class 2573 // type shall have a user-declared default 2574 // constructor. Otherwise, if no initializer is specified for 2575 // an object, the object and its subobjects, if any, have an 2576 // indeterminate initial value; if the object or any of its 2577 // subobjects are of const-qualified type, the program is 2578 // ill-formed. 2579 // 2580 // This isn't technically an error in C, so we don't diagnose it. 2581 // 2582 // FIXME: Actually perform the POD/user-defined default 2583 // constructor check. 2584 if (getLangOptions().CPlusPlus && 2585 Context.getCanonicalType(Type).isConstQualified() && 2586 Var->getStorageClass() != VarDecl::Extern) 2587 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2588 << Var->getName() 2589 << SourceRange(Var->getLocation(), Var->getLocation()); 2590#endif 2591 } 2592} 2593 2594Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2595 unsigned NumDecls) { 2596 llvm::SmallVector<Decl*, 8> Decls; 2597 2598 for (unsigned i = 0; i != NumDecls; ++i) 2599 if (Decl *D = Group[i].getAs<Decl>()) 2600 Decls.push_back(D); 2601 2602 // Perform semantic analysis that depends on having fully processed both 2603 // the declarator and initializer. 2604 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2605 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2606 if (!IDecl) 2607 continue; 2608 QualType T = IDecl->getType(); 2609 2610 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2611 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2612 if (IDecl->isBlockVarDecl() && 2613 IDecl->getStorageClass() != VarDecl::Extern) { 2614 if (!IDecl->isInvalidDecl() && 2615 RequireCompleteType(IDecl->getLocation(), T, 2616 diag::err_typecheck_decl_incomplete_type)) 2617 IDecl->setInvalidDecl(); 2618 } 2619 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2620 // object that has file scope without an initializer, and without a 2621 // storage-class specifier or with the storage-class specifier "static", 2622 // constitutes a tentative definition. Note: A tentative definition with 2623 // external linkage is valid (C99 6.2.2p5). 2624 if (IDecl->isTentativeDefinition(Context)) { 2625 QualType CheckType = T; 2626 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2627 2628 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2629 if (ArrayT) { 2630 CheckType = ArrayT->getElementType(); 2631 DiagID = diag::err_illegal_decl_array_incomplete_type; 2632 } 2633 2634 if (IDecl->isInvalidDecl()) { 2635 // Do nothing with invalid declarations 2636 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2637 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2638 // C99 6.9.2p3: If the declaration of an identifier for an object is 2639 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2640 // declared type shall not be an incomplete type. 2641 IDecl->setInvalidDecl(); 2642 } 2643 } 2644 } 2645 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2646 &Decls[0], Decls.size())); 2647} 2648 2649 2650/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2651/// to introduce parameters into function prototype scope. 2652Sema::DeclPtrTy 2653Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2654 const DeclSpec &DS = D.getDeclSpec(); 2655 2656 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2657 VarDecl::StorageClass StorageClass = VarDecl::None; 2658 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2659 StorageClass = VarDecl::Register; 2660 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2661 Diag(DS.getStorageClassSpecLoc(), 2662 diag::err_invalid_storage_class_in_func_decl); 2663 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2664 } 2665 if (DS.isThreadSpecified()) { 2666 Diag(DS.getThreadSpecLoc(), 2667 diag::err_invalid_storage_class_in_func_decl); 2668 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2669 } 2670 DiagnoseFunctionSpecifiers(D); 2671 2672 // Check that there are no default arguments inside the type of this 2673 // parameter (C++ only). 2674 if (getLangOptions().CPlusPlus) 2675 CheckExtraCXXDefaultArguments(D); 2676 2677 // In this context, we *do not* check D.getInvalidType(). If the declarator 2678 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2679 // though it will not reflect the user specified type. 2680 QualType parmDeclType = GetTypeForDeclarator(D, S); 2681 if (parmDeclType.isNull()) { 2682 D.setInvalidType(true); 2683 parmDeclType = Context.IntTy; 2684 } 2685 2686 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2687 // Can this happen for params? We already checked that they don't conflict 2688 // among each other. Here they can only shadow globals, which is ok. 2689 IdentifierInfo *II = D.getIdentifier(); 2690 if (II) { 2691 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2692 if (PrevDecl->isTemplateParameter()) { 2693 // Maybe we will complain about the shadowed template parameter. 2694 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2695 // Just pretend that we didn't see the previous declaration. 2696 PrevDecl = 0; 2697 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2698 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2699 2700 // Recover by removing the name 2701 II = 0; 2702 D.SetIdentifier(0, D.getIdentifierLoc()); 2703 } 2704 } 2705 } 2706 2707 // Parameters can not be abstract class types. 2708 // For record types, this is done by the AbstractClassUsageDiagnoser once 2709 // the class has been completely parsed. 2710 if (!CurContext->isRecord() && 2711 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2712 diag::err_abstract_type_in_decl, 2713 AbstractParamType)) 2714 D.setInvalidType(true); 2715 2716 QualType T = adjustParameterType(parmDeclType); 2717 2718 ParmVarDecl *New; 2719 if (T == parmDeclType) // parameter type did not need adjustment 2720 New = ParmVarDecl::Create(Context, CurContext, 2721 D.getIdentifierLoc(), II, 2722 parmDeclType, StorageClass, 2723 0); 2724 else // keep track of both the adjusted and unadjusted types 2725 New = OriginalParmVarDecl::Create(Context, CurContext, 2726 D.getIdentifierLoc(), II, T, 2727 parmDeclType, StorageClass, 0); 2728 2729 if (D.getInvalidType()) 2730 New->setInvalidDecl(); 2731 2732 // Parameter declarators cannot be interface types. All ObjC objects are 2733 // passed by reference. 2734 if (T->isObjCInterfaceType()) { 2735 Diag(D.getIdentifierLoc(), 2736 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2737 New->setInvalidDecl(); 2738 } 2739 2740 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2741 if (D.getCXXScopeSpec().isSet()) { 2742 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2743 << D.getCXXScopeSpec().getRange(); 2744 New->setInvalidDecl(); 2745 } 2746 2747 // Add the parameter declaration into this scope. 2748 S->AddDecl(DeclPtrTy::make(New)); 2749 if (II) 2750 IdResolver.AddDecl(New); 2751 2752 ProcessDeclAttributes(New, D); 2753 return DeclPtrTy::make(New); 2754} 2755 2756void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2757 SourceLocation LocAfterDecls) { 2758 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2759 "Not a function declarator!"); 2760 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2761 2762 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2763 // for a K&R function. 2764 if (!FTI.hasPrototype) { 2765 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2766 --i; 2767 if (FTI.ArgInfo[i].Param == 0) { 2768 std::string Code = " int "; 2769 Code += FTI.ArgInfo[i].Ident->getName(); 2770 Code += ";\n"; 2771 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2772 << FTI.ArgInfo[i].Ident 2773 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2774 2775 // Implicitly declare the argument as type 'int' for lack of a better 2776 // type. 2777 DeclSpec DS; 2778 const char* PrevSpec; // unused 2779 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2780 PrevSpec); 2781 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2782 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2783 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2784 } 2785 } 2786 } 2787} 2788 2789Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2790 Declarator &D) { 2791 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2792 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2793 "Not a function declarator!"); 2794 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2795 2796 if (FTI.hasPrototype) { 2797 // FIXME: Diagnose arguments without names in C. 2798 } 2799 2800 Scope *ParentScope = FnBodyScope->getParent(); 2801 2802 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2803 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2804} 2805 2806Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2807 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2808 2809 // See if this is a redefinition. 2810 const FunctionDecl *Definition; 2811 if (FD->getBody(Definition)) { 2812 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2813 Diag(Definition->getLocation(), diag::note_previous_definition); 2814 } 2815 2816 // Builtin functions cannot be defined. 2817 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2818 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2819 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2820 FD->setInvalidDecl(); 2821 } 2822 } 2823 2824 // The return type of a function definition must be complete 2825 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2826 QualType ResultType = FD->getResultType(); 2827 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2828 RequireCompleteType(FD->getLocation(), ResultType, 2829 diag::err_func_def_incomplete_result)) 2830 FD->setInvalidDecl(); 2831 2832 // GNU warning -Wmissing-prototypes: 2833 // Warn if a global function is defined without a previous 2834 // prototype declaration. This warning is issued even if the 2835 // definition itself provides a prototype. The aim is to detect 2836 // global functions that fail to be declared in header files. 2837 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2838 !FD->isMain()) { 2839 bool MissingPrototype = true; 2840 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2841 Prev; Prev = Prev->getPreviousDeclaration()) { 2842 // Ignore any declarations that occur in function or method 2843 // scope, because they aren't visible from the header. 2844 if (Prev->getDeclContext()->isFunctionOrMethod()) 2845 continue; 2846 2847 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2848 break; 2849 } 2850 2851 if (MissingPrototype) 2852 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2853 } 2854 2855 PushDeclContext(FnBodyScope, FD); 2856 2857 // Check the validity of our function parameters 2858 CheckParmsForFunctionDef(FD); 2859 2860 // Introduce our parameters into the function scope 2861 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2862 ParmVarDecl *Param = FD->getParamDecl(p); 2863 Param->setOwningFunction(FD); 2864 2865 // If this has an identifier, add it to the scope stack. 2866 if (Param->getIdentifier()) 2867 PushOnScopeChains(Param, FnBodyScope); 2868 } 2869 2870 // Checking attributes of current function definition 2871 // dllimport attribute. 2872 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2873 // dllimport attribute cannot be applied to definition. 2874 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2875 Diag(FD->getLocation(), 2876 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2877 << "dllimport"; 2878 FD->setInvalidDecl(); 2879 return DeclPtrTy::make(FD); 2880 } else { 2881 // If a symbol previously declared dllimport is later defined, the 2882 // attribute is ignored in subsequent references, and a warning is 2883 // emitted. 2884 Diag(FD->getLocation(), 2885 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2886 << FD->getNameAsCString() << "dllimport"; 2887 } 2888 } 2889 return DeclPtrTy::make(FD); 2890} 2891 2892static bool StatementCreatesScope(Stmt* S) { 2893 DeclStmt *DS = dyn_cast<DeclStmt>(S); 2894 if (DS == 0) return false; 2895 2896 for (DeclStmt::decl_iterator I = DS->decl_begin(), E = DS->decl_end(); 2897 I != E; ++I) { 2898 if (VarDecl *D = dyn_cast<VarDecl>(*I)) { 2899 if (D->getType()->isVariablyModifiedType() || 2900 D->hasAttr<CleanupAttr>()) 2901 return true; 2902 } else if (TypedefDecl *D = dyn_cast<TypedefDecl>(*I)) { 2903 if (D->getUnderlyingType()->isVariablyModifiedType()) 2904 return true; 2905 } 2906 } 2907 2908 return false; 2909} 2910 2911 2912void Sema::RecursiveCalcLabelScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2913 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2914 std::vector<void*>& ScopeStack, 2915 Stmt* CurStmt, 2916 Stmt* ParentCompoundStmt) { 2917 for (Stmt::child_iterator i = CurStmt->child_begin(); 2918 i != CurStmt->child_end(); ++i) { 2919 if (!*i) continue; 2920 if (StatementCreatesScope(*i)) { 2921 ScopeStack.push_back(*i); 2922 PopScopeMap[*i] = ParentCompoundStmt; 2923 } else if (isa<LabelStmt>(CurStmt)) { 2924 LabelScopeMap[CurStmt] = ScopeStack.size() ? ScopeStack.back() : 0; 2925 } 2926 if (isa<DeclStmt>(*i)) continue; 2927 Stmt* CurCompound = isa<CompoundStmt>(*i) ? *i : ParentCompoundStmt; 2928 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, 2929 *i, CurCompound); 2930 } 2931 2932 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2933 ScopeStack.pop_back(); 2934 } 2935} 2936 2937void Sema::RecursiveCalcJumpScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2938 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2939 llvm::DenseMap<Stmt*, void*>& GotoScopeMap, 2940 std::vector<void*>& ScopeStack, 2941 Stmt* CurStmt) { 2942 for (Stmt::child_iterator i = CurStmt->child_begin(); 2943 i != CurStmt->child_end(); ++i) { 2944 if (!*i) continue; 2945 if (StatementCreatesScope(*i)) { 2946 ScopeStack.push_back(*i); 2947 } else if (GotoStmt* GS = dyn_cast<GotoStmt>(*i)) { 2948 void* LScope = LabelScopeMap[GS->getLabel()]; 2949 if (LScope) { 2950 bool foundScopeInStack = false; 2951 for (unsigned i = ScopeStack.size(); i > 0; --i) { 2952 if (LScope == ScopeStack[i-1]) { 2953 foundScopeInStack = true; 2954 break; 2955 } 2956 } 2957 if (!foundScopeInStack) { 2958 Diag(GS->getSourceRange().getBegin(), diag::err_goto_into_scope); 2959 } 2960 } 2961 } 2962 if (isa<DeclStmt>(*i)) continue; 2963 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, 2964 ScopeStack, *i); 2965 } 2966 2967 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2968 ScopeStack.pop_back(); 2969 } 2970} 2971 2972Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 2973 Decl *dcl = D.getAs<Decl>(); 2974 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2975 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2976 FD->setBody(cast<CompoundStmt>(Body)); 2977 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2978 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2979 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2980 MD->setBody(cast<CompoundStmt>(Body)); 2981 } else { 2982 Body->Destroy(Context); 2983 return DeclPtrTy(); 2984 } 2985 PopDeclContext(); 2986 // Verify and clean out per-function state. 2987 2988 bool HaveLabels = !LabelMap.empty(); 2989 // Check goto/label use. 2990 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2991 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2992 // Verify that we have no forward references left. If so, there was a goto 2993 // or address of a label taken, but no definition of it. Label fwd 2994 // definitions are indicated with a null substmt. 2995 if (I->second->getSubStmt() == 0) { 2996 LabelStmt *L = I->second; 2997 // Emit error. 2998 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2999 3000 // At this point, we have gotos that use the bogus label. Stitch it into 3001 // the function body so that they aren't leaked and that the AST is well 3002 // formed. 3003 if (Body) { 3004#if 0 3005 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 3006 // and the AST is malformed anyway. We should just blow away 'L'. 3007 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3008 cast<CompoundStmt>(Body)->push_back(L); 3009#else 3010 L->Destroy(Context); 3011#endif 3012 } else { 3013 // The whole function wasn't parsed correctly, just delete this. 3014 L->Destroy(Context); 3015 } 3016 } 3017 } 3018 LabelMap.clear(); 3019 3020 if (!Body) return D; 3021 3022 if (HaveLabels) { 3023 llvm::DenseMap<Stmt*, void*> LabelScopeMap; 3024 llvm::DenseMap<void*, Stmt*> PopScopeMap; 3025 llvm::DenseMap<Stmt*, void*> GotoScopeMap; 3026 std::vector<void*> ScopeStack; 3027 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, Body, Body); 3028 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, ScopeStack, Body); 3029 } 3030 3031 return D; 3032} 3033 3034/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3035/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3036NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3037 IdentifierInfo &II, Scope *S) { 3038 // Before we produce a declaration for an implicitly defined 3039 // function, see whether there was a locally-scoped declaration of 3040 // this name as a function or variable. If so, use that 3041 // (non-visible) declaration, and complain about it. 3042 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3043 = LocallyScopedExternalDecls.find(&II); 3044 if (Pos != LocallyScopedExternalDecls.end()) { 3045 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3046 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3047 return Pos->second; 3048 } 3049 3050 // Extension in C99. Legal in C90, but warn about it. 3051 if (getLangOptions().C99) 3052 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3053 else 3054 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3055 3056 // FIXME: handle stuff like: 3057 // void foo() { extern float X(); } 3058 // void bar() { X(); } <-- implicit decl for X in another scope. 3059 3060 // Set a Declarator for the implicit definition: int foo(); 3061 const char *Dummy; 3062 DeclSpec DS; 3063 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3064 Error = Error; // Silence warning. 3065 assert(!Error && "Error setting up implicit decl!"); 3066 Declarator D(DS, Declarator::BlockContext); 3067 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3068 0, 0, 0, Loc, D), 3069 SourceLocation()); 3070 D.SetIdentifier(&II, Loc); 3071 3072 // Insert this function into translation-unit scope. 3073 3074 DeclContext *PrevDC = CurContext; 3075 CurContext = Context.getTranslationUnitDecl(); 3076 3077 FunctionDecl *FD = 3078 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3079 FD->setImplicit(); 3080 3081 CurContext = PrevDC; 3082 3083 AddKnownFunctionAttributes(FD); 3084 3085 return FD; 3086} 3087 3088/// \brief Adds any function attributes that we know a priori based on 3089/// the declaration of this function. 3090/// 3091/// These attributes can apply both to implicitly-declared builtins 3092/// (like __builtin___printf_chk) or to library-declared functions 3093/// like NSLog or printf. 3094void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3095 if (FD->isInvalidDecl()) 3096 return; 3097 3098 // If this is a built-in function, map its builtin attributes to 3099 // actual attributes. 3100 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3101 // Handle printf-formatting attributes. 3102 unsigned FormatIdx; 3103 bool HasVAListArg; 3104 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3105 if (!FD->getAttr<FormatAttr>()) 3106 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3107 FormatIdx + 2)); 3108 } 3109 3110 // Mark const if we don't care about errno and that is the only 3111 // thing preventing the function from being const. This allows 3112 // IRgen to use LLVM intrinsics for such functions. 3113 if (!getLangOptions().MathErrno && 3114 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3115 if (!FD->getAttr<ConstAttr>()) 3116 FD->addAttr(::new (Context) ConstAttr()); 3117 } 3118 } 3119 3120 IdentifierInfo *Name = FD->getIdentifier(); 3121 if (!Name) 3122 return; 3123 if ((!getLangOptions().CPlusPlus && 3124 FD->getDeclContext()->isTranslationUnit()) || 3125 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3126 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3127 LinkageSpecDecl::lang_c)) { 3128 // Okay: this could be a libc/libm/Objective-C function we know 3129 // about. 3130 } else 3131 return; 3132 3133 unsigned KnownID; 3134 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3135 if (KnownFunctionIDs[KnownID] == Name) 3136 break; 3137 3138 switch (KnownID) { 3139 case id_NSLog: 3140 case id_NSLogv: 3141 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3142 // FIXME: We known better than our headers. 3143 const_cast<FormatAttr *>(Format)->setType("printf"); 3144 } else 3145 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3146 break; 3147 3148 case id_asprintf: 3149 case id_vasprintf: 3150 if (!FD->getAttr<FormatAttr>()) 3151 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3152 break; 3153 3154 default: 3155 // Unknown function or known function without any attributes to 3156 // add. Do nothing. 3157 break; 3158 } 3159} 3160 3161TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3162 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3163 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3164 3165 // Scope manipulation handled by caller. 3166 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3167 D.getIdentifierLoc(), 3168 D.getIdentifier(), 3169 T); 3170 3171 if (TagType *TT = dyn_cast<TagType>(T)) { 3172 TagDecl *TD = TT->getDecl(); 3173 3174 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3175 // keep track of the TypedefDecl. 3176 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3177 TD->setTypedefForAnonDecl(NewTD); 3178 } 3179 3180 if (D.getInvalidType()) 3181 NewTD->setInvalidDecl(); 3182 return NewTD; 3183} 3184 3185/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3186/// former case, Name will be non-null. In the later case, Name will be null. 3187/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3188/// reference/declaration/definition of a tag. 3189Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3190 SourceLocation KWLoc, const CXXScopeSpec &SS, 3191 IdentifierInfo *Name, SourceLocation NameLoc, 3192 AttributeList *Attr, AccessSpecifier AS) { 3193 // If this is not a definition, it must have a name. 3194 assert((Name != 0 || TK == TK_Definition) && 3195 "Nameless record must be a definition!"); 3196 3197 TagDecl::TagKind Kind; 3198 switch (TagSpec) { 3199 default: assert(0 && "Unknown tag type!"); 3200 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3201 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3202 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3203 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3204 } 3205 3206 DeclContext *SearchDC = CurContext; 3207 DeclContext *DC = CurContext; 3208 NamedDecl *PrevDecl = 0; 3209 3210 bool Invalid = false; 3211 3212 if (Name && SS.isNotEmpty()) { 3213 // We have a nested-name tag ('struct foo::bar'). 3214 3215 // Check for invalid 'foo::'. 3216 if (SS.isInvalid()) { 3217 Name = 0; 3218 goto CreateNewDecl; 3219 } 3220 3221 // FIXME: RequireCompleteDeclContext(SS)? 3222 DC = computeDeclContext(SS); 3223 SearchDC = DC; 3224 // Look-up name inside 'foo::'. 3225 PrevDecl = dyn_cast_or_null<TagDecl>( 3226 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3227 3228 // A tag 'foo::bar' must already exist. 3229 if (PrevDecl == 0) { 3230 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3231 Name = 0; 3232 goto CreateNewDecl; 3233 } 3234 } else if (Name) { 3235 // If this is a named struct, check to see if there was a previous forward 3236 // declaration or definition. 3237 // FIXME: We're looking into outer scopes here, even when we 3238 // shouldn't be. Doing so can result in ambiguities that we 3239 // shouldn't be diagnosing. 3240 LookupResult R = LookupName(S, Name, LookupTagName, 3241 /*RedeclarationOnly=*/(TK != TK_Reference)); 3242 if (R.isAmbiguous()) { 3243 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3244 // FIXME: This is not best way to recover from case like: 3245 // 3246 // struct S s; 3247 // 3248 // causes needless "incomplete type" error later. 3249 Name = 0; 3250 PrevDecl = 0; 3251 Invalid = true; 3252 } 3253 else 3254 PrevDecl = R; 3255 3256 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3257 // FIXME: This makes sure that we ignore the contexts associated 3258 // with C structs, unions, and enums when looking for a matching 3259 // tag declaration or definition. See the similar lookup tweak 3260 // in Sema::LookupName; is there a better way to deal with this? 3261 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3262 SearchDC = SearchDC->getParent(); 3263 } 3264 } 3265 3266 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3267 // Maybe we will complain about the shadowed template parameter. 3268 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3269 // Just pretend that we didn't see the previous declaration. 3270 PrevDecl = 0; 3271 } 3272 3273 if (PrevDecl) { 3274 // Check whether the previous declaration is usable. 3275 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3276 3277 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3278 // If this is a use of a previous tag, or if the tag is already declared 3279 // in the same scope (so that the definition/declaration completes or 3280 // rementions the tag), reuse the decl. 3281 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3282 // Make sure that this wasn't declared as an enum and now used as a 3283 // struct or something similar. 3284 if (PrevTagDecl->getTagKind() != Kind) { 3285 bool SafeToContinue 3286 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3287 Kind != TagDecl::TK_enum); 3288 if (SafeToContinue) 3289 Diag(KWLoc, diag::err_use_with_wrong_tag) 3290 << Name 3291 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3292 PrevTagDecl->getKindName()); 3293 else 3294 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3295 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3296 3297 if (SafeToContinue) 3298 Kind = PrevTagDecl->getTagKind(); 3299 else { 3300 // Recover by making this an anonymous redefinition. 3301 Name = 0; 3302 PrevDecl = 0; 3303 Invalid = true; 3304 } 3305 } 3306 3307 if (!Invalid) { 3308 // If this is a use, just return the declaration we found. 3309 3310 // FIXME: In the future, return a variant or some other clue 3311 // for the consumer of this Decl to know it doesn't own it. 3312 // For our current ASTs this shouldn't be a problem, but will 3313 // need to be changed with DeclGroups. 3314 if (TK == TK_Reference) 3315 return DeclPtrTy::make(PrevDecl); 3316 3317 // Diagnose attempts to redefine a tag. 3318 if (TK == TK_Definition) { 3319 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3320 Diag(NameLoc, diag::err_redefinition) << Name; 3321 Diag(Def->getLocation(), diag::note_previous_definition); 3322 // If this is a redefinition, recover by making this 3323 // struct be anonymous, which will make any later 3324 // references get the previous definition. 3325 Name = 0; 3326 PrevDecl = 0; 3327 Invalid = true; 3328 } else { 3329 // If the type is currently being defined, complain 3330 // about a nested redefinition. 3331 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3332 if (Tag->isBeingDefined()) { 3333 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3334 Diag(PrevTagDecl->getLocation(), 3335 diag::note_previous_definition); 3336 Name = 0; 3337 PrevDecl = 0; 3338 Invalid = true; 3339 } 3340 } 3341 3342 // Okay, this is definition of a previously declared or referenced 3343 // tag PrevDecl. We're going to create a new Decl for it. 3344 } 3345 } 3346 // If we get here we have (another) forward declaration or we 3347 // have a definition. Just create a new decl. 3348 } else { 3349 // If we get here, this is a definition of a new tag type in a nested 3350 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3351 // new decl/type. We set PrevDecl to NULL so that the entities 3352 // have distinct types. 3353 PrevDecl = 0; 3354 } 3355 // If we get here, we're going to create a new Decl. If PrevDecl 3356 // is non-NULL, it's a definition of the tag declared by 3357 // PrevDecl. If it's NULL, we have a new definition. 3358 } else { 3359 // PrevDecl is a namespace, template, or anything else 3360 // that lives in the IDNS_Tag identifier namespace. 3361 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3362 // The tag name clashes with a namespace name, issue an error and 3363 // recover by making this tag be anonymous. 3364 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3365 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3366 Name = 0; 3367 PrevDecl = 0; 3368 Invalid = true; 3369 } else { 3370 // The existing declaration isn't relevant to us; we're in a 3371 // new scope, so clear out the previous declaration. 3372 PrevDecl = 0; 3373 } 3374 } 3375 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3376 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3377 // C.scope.pdecl]p5: 3378 // -- for an elaborated-type-specifier of the form 3379 // 3380 // class-key identifier 3381 // 3382 // if the elaborated-type-specifier is used in the 3383 // decl-specifier-seq or parameter-declaration-clause of a 3384 // function defined in namespace scope, the identifier is 3385 // declared as a class-name in the namespace that contains 3386 // the declaration; otherwise, except as a friend 3387 // declaration, the identifier is declared in the smallest 3388 // non-class, non-function-prototype scope that contains the 3389 // declaration. 3390 // 3391 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3392 // C structs and unions. 3393 // 3394 // GNU C also supports this behavior as part of its incomplete 3395 // enum types extension, while GNU C++ does not. 3396 // 3397 // Find the context where we'll be declaring the tag. 3398 // FIXME: We would like to maintain the current DeclContext as the 3399 // lexical context, 3400 while (SearchDC->isRecord()) 3401 SearchDC = SearchDC->getParent(); 3402 3403 // Find the scope where we'll be declaring the tag. 3404 while (S->isClassScope() || 3405 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3406 ((S->getFlags() & Scope::DeclScope) == 0) || 3407 (S->getEntity() && 3408 ((DeclContext *)S->getEntity())->isTransparentContext())) 3409 S = S->getParent(); 3410 } 3411 3412CreateNewDecl: 3413 3414 // If there is an identifier, use the location of the identifier as the 3415 // location of the decl, otherwise use the location of the struct/union 3416 // keyword. 3417 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3418 3419 // Otherwise, create a new declaration. If there is a previous 3420 // declaration of the same entity, the two will be linked via 3421 // PrevDecl. 3422 TagDecl *New; 3423 3424 if (Kind == TagDecl::TK_enum) { 3425 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3426 // enum X { A, B, C } D; D should chain to X. 3427 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3428 cast_or_null<EnumDecl>(PrevDecl)); 3429 // If this is an undefined enum, warn. 3430 if (TK != TK_Definition && !Invalid) { 3431 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3432 : diag::ext_forward_ref_enum; 3433 Diag(Loc, DK); 3434 } 3435 } else { 3436 // struct/union/class 3437 3438 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3439 // struct X { int A; } D; D should chain to X. 3440 if (getLangOptions().CPlusPlus) 3441 // FIXME: Look for a way to use RecordDecl for simple structs. 3442 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3443 cast_or_null<CXXRecordDecl>(PrevDecl)); 3444 else 3445 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3446 cast_or_null<RecordDecl>(PrevDecl)); 3447 } 3448 3449 if (Kind != TagDecl::TK_enum) { 3450 // Handle #pragma pack: if the #pragma pack stack has non-default 3451 // alignment, make up a packed attribute for this decl. These 3452 // attributes are checked when the ASTContext lays out the 3453 // structure. 3454 // 3455 // It is important for implementing the correct semantics that this 3456 // happen here (in act on tag decl). The #pragma pack stack is 3457 // maintained as a result of parser callbacks which can occur at 3458 // many points during the parsing of a struct declaration (because 3459 // the #pragma tokens are effectively skipped over during the 3460 // parsing of the struct). 3461 if (unsigned Alignment = getPragmaPackAlignment()) 3462 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3463 } 3464 3465 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3466 // C++ [dcl.typedef]p3: 3467 // [...] Similarly, in a given scope, a class or enumeration 3468 // shall not be declared with the same name as a typedef-name 3469 // that is declared in that scope and refers to a type other 3470 // than the class or enumeration itself. 3471 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3472 TypedefDecl *PrevTypedef = 0; 3473 if (Lookup.getKind() == LookupResult::Found) 3474 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3475 3476 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3477 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3478 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3479 Diag(Loc, diag::err_tag_definition_of_typedef) 3480 << Context.getTypeDeclType(New) 3481 << PrevTypedef->getUnderlyingType(); 3482 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3483 Invalid = true; 3484 } 3485 } 3486 3487 if (Invalid) 3488 New->setInvalidDecl(); 3489 3490 if (Attr) 3491 ProcessDeclAttributeList(New, Attr); 3492 3493 // If we're declaring or defining a tag in function prototype scope 3494 // in C, note that this type can only be used within the function. 3495 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3496 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3497 3498 // Set the lexical context. If the tag has a C++ scope specifier, the 3499 // lexical context will be different from the semantic context. 3500 New->setLexicalDeclContext(CurContext); 3501 3502 // Set the access specifier. 3503 SetMemberAccessSpecifier(New, PrevDecl, AS); 3504 3505 if (TK == TK_Definition) 3506 New->startDefinition(); 3507 3508 // If this has an identifier, add it to the scope stack. 3509 if (Name) { 3510 S = getNonFieldDeclScope(S); 3511 PushOnScopeChains(New, S); 3512 } else { 3513 CurContext->addDecl(Context, New); 3514 } 3515 3516 return DeclPtrTy::make(New); 3517} 3518 3519void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3520 AdjustDeclIfTemplate(TagD); 3521 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3522 3523 // Enter the tag context. 3524 PushDeclContext(S, Tag); 3525 3526 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3527 FieldCollector->StartClass(); 3528 3529 if (Record->getIdentifier()) { 3530 // C++ [class]p2: 3531 // [...] The class-name is also inserted into the scope of the 3532 // class itself; this is known as the injected-class-name. For 3533 // purposes of access checking, the injected-class-name is treated 3534 // as if it were a public member name. 3535 CXXRecordDecl *InjectedClassName 3536 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3537 CurContext, Record->getLocation(), 3538 Record->getIdentifier(), Record); 3539 InjectedClassName->setImplicit(); 3540 InjectedClassName->setAccess(AS_public); 3541 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3542 InjectedClassName->setDescribedClassTemplate(Template); 3543 PushOnScopeChains(InjectedClassName, S); 3544 assert(InjectedClassName->isInjectedClassName() && 3545 "Broken injected-class-name"); 3546 } 3547 } 3548} 3549 3550void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3551 AdjustDeclIfTemplate(TagD); 3552 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3553 3554 if (isa<CXXRecordDecl>(Tag)) 3555 FieldCollector->FinishClass(); 3556 3557 // Exit this scope of this tag's definition. 3558 PopDeclContext(); 3559 3560 // Notify the consumer that we've defined a tag. 3561 Consumer.HandleTagDeclDefinition(Tag); 3562} 3563 3564bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3565 QualType FieldTy, const Expr *BitWidth) { 3566 // C99 6.7.2.1p4 - verify the field type. 3567 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3568 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3569 // Handle incomplete types with specific error. 3570 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3571 return true; 3572 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3573 << FieldName << FieldTy << BitWidth->getSourceRange(); 3574 } 3575 3576 // If the bit-width is type- or value-dependent, don't try to check 3577 // it now. 3578 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3579 return false; 3580 3581 llvm::APSInt Value; 3582 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3583 return true; 3584 3585 // Zero-width bitfield is ok for anonymous field. 3586 if (Value == 0 && FieldName) 3587 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3588 3589 if (Value.isSigned() && Value.isNegative()) 3590 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3591 << FieldName << Value.toString(10); 3592 3593 if (!FieldTy->isDependentType()) { 3594 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3595 // FIXME: We won't need the 0 size once we check that the field type is valid. 3596 if (TypeSize && Value.getZExtValue() > TypeSize) 3597 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3598 << FieldName << (unsigned)TypeSize; 3599 } 3600 3601 return false; 3602} 3603 3604/// ActOnField - Each field of a struct/union/class is passed into this in order 3605/// to create a FieldDecl object for it. 3606Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3607 SourceLocation DeclStart, 3608 Declarator &D, ExprTy *BitfieldWidth) { 3609 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3610 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3611 AS_public); 3612 return DeclPtrTy::make(Res); 3613} 3614 3615/// HandleField - Analyze a field of a C struct or a C++ data member. 3616/// 3617FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3618 SourceLocation DeclStart, 3619 Declarator &D, Expr *BitWidth, 3620 AccessSpecifier AS) { 3621 IdentifierInfo *II = D.getIdentifier(); 3622 SourceLocation Loc = DeclStart; 3623 if (II) Loc = D.getIdentifierLoc(); 3624 3625 QualType T = GetTypeForDeclarator(D, S); 3626 if (getLangOptions().CPlusPlus) 3627 CheckExtraCXXDefaultArguments(D); 3628 3629 DiagnoseFunctionSpecifiers(D); 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 3668 // If we receive a broken type, recover by assuming 'int' and 3669 // marking this declaration as invalid. 3670 if (T.isNull()) { 3671 InvalidDecl = true; 3672 T = Context.IntTy; 3673 } 3674 3675 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3676 // than a variably modified type. 3677 if (T->isVariablyModifiedType()) { 3678 bool SizeIsNegative; 3679 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3680 SizeIsNegative); 3681 if (!FixedTy.isNull()) { 3682 Diag(Loc, diag::warn_illegal_constant_array_size); 3683 T = FixedTy; 3684 } else { 3685 if (SizeIsNegative) 3686 Diag(Loc, diag::err_typecheck_negative_array_size); 3687 else 3688 Diag(Loc, diag::err_typecheck_field_variable_size); 3689 T = Context.IntTy; 3690 InvalidDecl = true; 3691 } 3692 } 3693 3694 // Fields can not have abstract class types 3695 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3696 AbstractFieldType)) 3697 InvalidDecl = true; 3698 3699 // If this is declared as a bit-field, check the bit-field. 3700 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3701 InvalidDecl = true; 3702 DeleteExpr(BitWidth); 3703 BitWidth = 0; 3704 } 3705 3706 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3707 Mutable); 3708 3709 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3710 Diag(Loc, diag::err_duplicate_member) << II; 3711 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3712 NewFD->setInvalidDecl(); 3713 Record->setInvalidDecl(); 3714 } 3715 3716 if (getLangOptions().CPlusPlus && !T->isPODType()) 3717 cast<CXXRecordDecl>(Record)->setPOD(false); 3718 3719 // FIXME: We need to pass in the attributes given an AST 3720 // representation, not a parser representation. 3721 if (D) 3722 ProcessDeclAttributes(NewFD, *D); 3723 3724 if (T.isObjCGCWeak()) 3725 Diag(Loc, diag::warn_attribute_weak_on_field); 3726 3727 if (InvalidDecl) 3728 NewFD->setInvalidDecl(); 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 bool InvalidDecl = false; 3776 if (T.isNull()) { 3777 InvalidDecl = true; 3778 T = Context.IntTy; 3779 } 3780 3781 if (BitWidth) { 3782 // 6.7.2.1p3, 6.7.2.1p4 3783 if (VerifyBitField(Loc, II, T, BitWidth)) { 3784 InvalidDecl = true; 3785 DeleteExpr(BitWidth); 3786 BitWidth = 0; 3787 } 3788 } else { 3789 // Not a bitfield. 3790 3791 // validate II. 3792 3793 } 3794 3795 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3796 // than a variably modified type. 3797 if (T->isVariablyModifiedType()) { 3798 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3799 InvalidDecl = true; 3800 } 3801 3802 // Get the visibility (access control) for this ivar. 3803 ObjCIvarDecl::AccessControl ac = 3804 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3805 : ObjCIvarDecl::None; 3806 3807 // Construct the decl. 3808 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3809 (Expr *)BitfieldWidth); 3810 3811 if (II) { 3812 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3813 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3814 && !isa<TagDecl>(PrevDecl)) { 3815 Diag(Loc, diag::err_duplicate_member) << II; 3816 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3817 NewID->setInvalidDecl(); 3818 } 3819 } 3820 3821 // Process attributes attached to the ivar. 3822 ProcessDeclAttributes(NewID, D); 3823 3824 if (D.getInvalidType() || InvalidDecl) 3825 NewID->setInvalidDecl(); 3826 3827 if (II) { 3828 // FIXME: When interfaces are DeclContexts, we'll need to add 3829 // these to the interface. 3830 S->AddDecl(DeclPtrTy::make(NewID)); 3831 IdResolver.AddDecl(NewID); 3832 } 3833 3834 return DeclPtrTy::make(NewID); 3835} 3836 3837void Sema::ActOnFields(Scope* S, 3838 SourceLocation RecLoc, DeclPtrTy RecDecl, 3839 DeclPtrTy *Fields, unsigned NumFields, 3840 SourceLocation LBrac, SourceLocation RBrac, 3841 AttributeList *Attr) { 3842 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3843 assert(EnclosingDecl && "missing record or interface decl"); 3844 3845 // If the decl this is being inserted into is invalid, then it may be a 3846 // redeclaration or some other bogus case. Don't try to add fields to it. 3847 if (EnclosingDecl->isInvalidDecl()) { 3848 // FIXME: Deallocate fields? 3849 return; 3850 } 3851 3852 3853 // Verify that all the fields are okay. 3854 unsigned NumNamedMembers = 0; 3855 llvm::SmallVector<FieldDecl*, 32> RecFields; 3856 3857 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3858 for (unsigned i = 0; i != NumFields; ++i) { 3859 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3860 3861 // Get the type for the field. 3862 Type *FDTy = FD->getType().getTypePtr(); 3863 3864 if (!FD->isAnonymousStructOrUnion()) { 3865 // Remember all fields written by the user. 3866 RecFields.push_back(FD); 3867 } 3868 3869 // If the field is already invalid for some reason, don't emit more 3870 // diagnostics about it. 3871 if (FD->isInvalidDecl()) 3872 continue; 3873 3874 // C99 6.7.2.1p2: 3875 // A structure or union shall not contain a member with 3876 // incomplete or function type (hence, a structure shall not 3877 // contain an instance of itself, but may contain a pointer to 3878 // an instance of itself), except that the last member of a 3879 // structure with more than one named member may have incomplete 3880 // array type; such a structure (and any union containing, 3881 // possibly recursively, a member that is such a structure) 3882 // shall not be a member of a structure or an element of an 3883 // array. 3884 if (FDTy->isFunctionType()) { 3885 // Field declared as a function. 3886 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3887 << FD->getDeclName(); 3888 FD->setInvalidDecl(); 3889 EnclosingDecl->setInvalidDecl(); 3890 continue; 3891 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3892 Record && Record->isStruct()) { 3893 // Flexible array member. 3894 if (NumNamedMembers < 1) { 3895 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3896 << FD->getDeclName(); 3897 FD->setInvalidDecl(); 3898 EnclosingDecl->setInvalidDecl(); 3899 continue; 3900 } 3901 // Okay, we have a legal flexible array member at the end of the struct. 3902 if (Record) 3903 Record->setHasFlexibleArrayMember(true); 3904 } else if (!FDTy->isDependentType() && 3905 RequireCompleteType(FD->getLocation(), FD->getType(), 3906 diag::err_field_incomplete)) { 3907 // Incomplete type 3908 FD->setInvalidDecl(); 3909 EnclosingDecl->setInvalidDecl(); 3910 continue; 3911 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3912 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3913 // If this is a member of a union, then entire union becomes "flexible". 3914 if (Record && Record->isUnion()) { 3915 Record->setHasFlexibleArrayMember(true); 3916 } else { 3917 // If this is a struct/class and this is not the last element, reject 3918 // it. Note that GCC supports variable sized arrays in the middle of 3919 // structures. 3920 if (i != NumFields-1) 3921 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3922 << FD->getDeclName(); 3923 else { 3924 // We support flexible arrays at the end of structs in 3925 // other structs as an extension. 3926 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3927 << FD->getDeclName(); 3928 if (Record) 3929 Record->setHasFlexibleArrayMember(true); 3930 } 3931 } 3932 } 3933 } else if (FDTy->isObjCInterfaceType()) { 3934 /// A field cannot be an Objective-c object 3935 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3936 FD->setInvalidDecl(); 3937 EnclosingDecl->setInvalidDecl(); 3938 continue; 3939 } 3940 // Keep track of the number of named members. 3941 if (FD->getIdentifier()) 3942 ++NumNamedMembers; 3943 } 3944 3945 // Okay, we successfully defined 'Record'. 3946 if (Record) { 3947 Record->completeDefinition(Context); 3948 } else { 3949 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3950 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3951 ID->setIVarList(ClsFields, RecFields.size(), Context); 3952 ID->setLocEnd(RBrac); 3953 3954 // Must enforce the rule that ivars in the base classes may not be 3955 // duplicates. 3956 if (ID->getSuperClass()) { 3957 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3958 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3959 ObjCIvarDecl* Ivar = (*IVI); 3960 IdentifierInfo *II = Ivar->getIdentifier(); 3961 ObjCIvarDecl* prevIvar = 3962 ID->getSuperClass()->lookupInstanceVariable(Context, II); 3963 if (prevIvar) { 3964 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3965 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3966 } 3967 } 3968 } 3969 } else if (ObjCImplementationDecl *IMPDecl = 3970 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3971 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3972 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 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