SemaDecl.cpp revision ab197baec16bacade82325fb274cf6b992ac5d8a
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> 31 32using namespace clang; 33 34/// \brief If the identifier refers to a type name within this scope, 35/// return the declaration of that type. 36/// 37/// This routine performs ordinary name lookup of the identifier II 38/// within the given scope, with optional C++ scope specifier SS, to 39/// determine whether the name refers to a type. If so, returns an 40/// opaque pointer (actually a QualType) corresponding to that 41/// type. Otherwise, returns NULL. 42/// 43/// If name lookup results in an ambiguity, this routine will complain 44/// and then return NULL. 45Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 46 Scope *S, const CXXScopeSpec *SS) { 47 Decl *IIDecl = 0; 48 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, false); 49 switch (Result.getKind()) { 50 case LookupResult::NotFound: 51 case LookupResult::FoundOverloaded: 52 return 0; 53 54 case LookupResult::AmbiguousBaseSubobjectTypes: 55 case LookupResult::AmbiguousBaseSubobjects: 56 case LookupResult::AmbiguousReference: 57 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 58 return 0; 59 60 case LookupResult::Found: 61 IIDecl = Result.getAsDecl(); 62 break; 63 } 64 65 if (IIDecl) { 66 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) 67 return Context.getTypeDeclType(TD).getAsOpaquePtr(); 68 else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) 69 return Context.getObjCInterfaceType(IDecl).getAsOpaquePtr(); 70 } 71 return 0; 72} 73 74DeclContext *Sema::getContainingDC(DeclContext *DC) { 75 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 76 // A C++ out-of-line method will return to the file declaration context. 77 if (MD->isOutOfLineDefinition()) 78 return MD->getLexicalDeclContext(); 79 80 // A C++ inline method is parsed *after* the topmost class it was declared in 81 // is fully parsed (it's "complete"). 82 // The parsing of a C++ inline method happens at the declaration context of 83 // the topmost (non-nested) class it is lexically declared in. 84 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 85 DC = MD->getParent(); 86 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 87 DC = RD; 88 89 // Return the declaration context of the topmost class the inline method is 90 // declared in. 91 return DC; 92 } 93 94 if (isa<ObjCMethodDecl>(DC)) 95 return Context.getTranslationUnitDecl(); 96 97 if (Decl *D = dyn_cast<Decl>(DC)) 98 return D->getLexicalDeclContext(); 99 100 return DC->getLexicalParent(); 101} 102 103void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 104 assert(getContainingDC(DC) == CurContext && 105 "The next DeclContext should be lexically contained in the current one."); 106 CurContext = DC; 107 S->setEntity(DC); 108} 109 110void Sema::PopDeclContext() { 111 assert(CurContext && "DeclContext imbalance!"); 112 113 CurContext = getContainingDC(CurContext); 114} 115 116/// Add this decl to the scope shadowed decl chains. 117void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 118 // Move up the scope chain until we find the nearest enclosing 119 // non-transparent context. The declaration will be introduced into this 120 // scope. 121 while (S->getEntity() && 122 ((DeclContext *)S->getEntity())->isTransparentContext()) 123 S = S->getParent(); 124 125 S->AddDecl(D); 126 127 // Add scoped declarations into their context, so that they can be 128 // found later. Declarations without a context won't be inserted 129 // into any context. 130 CurContext->addDecl(D); 131 132 // C++ [basic.scope]p4: 133 // -- exactly one declaration shall declare a class name or 134 // enumeration name that is not a typedef name and the other 135 // declarations shall all refer to the same object or 136 // enumerator, or all refer to functions and function templates; 137 // in this case the class name or enumeration name is hidden. 138 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 139 // We are pushing the name of a tag (enum or class). 140 if (CurContext->getLookupContext() 141 == TD->getDeclContext()->getLookupContext()) { 142 // We're pushing the tag into the current context, which might 143 // require some reshuffling in the identifier resolver. 144 IdentifierResolver::iterator 145 I = IdResolver.begin(TD->getDeclName()), 146 IEnd = IdResolver.end(); 147 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 148 NamedDecl *PrevDecl = *I; 149 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 150 PrevDecl = *I, ++I) { 151 if (TD->declarationReplaces(*I)) { 152 // This is a redeclaration. Remove it from the chain and 153 // break out, so that we'll add in the shadowed 154 // declaration. 155 S->RemoveDecl(*I); 156 if (PrevDecl == *I) { 157 IdResolver.RemoveDecl(*I); 158 IdResolver.AddDecl(TD); 159 return; 160 } else { 161 IdResolver.RemoveDecl(*I); 162 break; 163 } 164 } 165 } 166 167 // There is already a declaration with the same name in the same 168 // scope, which is not a tag declaration. It must be found 169 // before we find the new declaration, so insert the new 170 // declaration at the end of the chain. 171 IdResolver.AddShadowedDecl(TD, PrevDecl); 172 173 return; 174 } 175 } 176 } else if (getLangOptions().CPlusPlus && isa<FunctionDecl>(D)) { 177 // We are pushing the name of a function, which might be an 178 // overloaded name. 179 FunctionDecl *FD = cast<FunctionDecl>(D); 180 IdentifierResolver::iterator Redecl 181 = std::find_if(IdResolver.begin(FD->getDeclName()), 182 IdResolver.end(), 183 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 184 FD)); 185 if (Redecl != IdResolver.end()) { 186 // There is already a declaration of a function on our 187 // IdResolver chain. Replace it with this declaration. 188 S->RemoveDecl(*Redecl); 189 IdResolver.RemoveDecl(*Redecl); 190 } 191 } 192 193 IdResolver.AddDecl(D); 194} 195 196void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 197 if (S->decl_empty()) return; 198 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 199 "Scope shouldn't contain decls!"); 200 201 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 202 I != E; ++I) { 203 Decl *TmpD = static_cast<Decl*>(*I); 204 assert(TmpD && "This decl didn't get pushed??"); 205 206 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 207 NamedDecl *D = cast<NamedDecl>(TmpD); 208 209 if (!D->getDeclName()) continue; 210 211 // Remove this name from our lexical scope. 212 IdResolver.RemoveDecl(D); 213 } 214} 215 216/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 217/// return 0 if one not found. 218ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 219 // The third "scope" argument is 0 since we aren't enabling lazy built-in 220 // creation from this context. 221 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 222 223 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 224} 225 226/// getNonFieldDeclScope - Retrieves the innermost scope, starting 227/// from S, where a non-field would be declared. This routine copes 228/// with the difference between C and C++ scoping rules in structs and 229/// unions. For example, the following code is well-formed in C but 230/// ill-formed in C++: 231/// @code 232/// struct S6 { 233/// enum { BAR } e; 234/// }; 235/// 236/// void test_S6() { 237/// struct S6 a; 238/// a.e = BAR; 239/// } 240/// @endcode 241/// For the declaration of BAR, this routine will return a different 242/// scope. The scope S will be the scope of the unnamed enumeration 243/// within S6. In C++, this routine will return the scope associated 244/// with S6, because the enumeration's scope is a transparent 245/// context but structures can contain non-field names. In C, this 246/// routine will return the translation unit scope, since the 247/// enumeration's scope is a transparent context and structures cannot 248/// contain non-field names. 249Scope *Sema::getNonFieldDeclScope(Scope *S) { 250 while (((S->getFlags() & Scope::DeclScope) == 0) || 251 (S->getEntity() && 252 ((DeclContext *)S->getEntity())->isTransparentContext()) || 253 (S->isClassScope() && !getLangOptions().CPlusPlus)) 254 S = S->getParent(); 255 return S; 256} 257 258void Sema::InitBuiltinVaListType() { 259 if (!Context.getBuiltinVaListType().isNull()) 260 return; 261 262 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 263 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 264 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 265 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 266} 267 268/// LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope. 269/// lazily create a decl for it. 270NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 271 Scope *S) { 272 Builtin::ID BID = (Builtin::ID)bid; 273 274 if (Context.BuiltinInfo.hasVAListUse(BID)) 275 InitBuiltinVaListType(); 276 277 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context); 278 FunctionDecl *New = FunctionDecl::Create(Context, 279 Context.getTranslationUnitDecl(), 280 SourceLocation(), II, R, 281 FunctionDecl::Extern, false); 282 283 // Create Decl objects for each parameter, adding them to the 284 // FunctionDecl. 285 if (FunctionTypeProto *FT = dyn_cast<FunctionTypeProto>(R)) { 286 llvm::SmallVector<ParmVarDecl*, 16> Params; 287 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 288 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 289 FT->getArgType(i), VarDecl::None, 0)); 290 New->setParams(Context, &Params[0], Params.size()); 291 } 292 293 294 295 // TUScope is the translation-unit scope to insert this function into. 296 // FIXME: This is hideous. We need to teach PushOnScopeChains to 297 // relate Scopes to DeclContexts, and probably eliminate CurContext 298 // entirely, but we're not there yet. 299 DeclContext *SavedContext = CurContext; 300 CurContext = Context.getTranslationUnitDecl(); 301 PushOnScopeChains(New, TUScope); 302 CurContext = SavedContext; 303 return New; 304} 305 306/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 307/// everything from the standard library is defined. 308NamespaceDecl *Sema::GetStdNamespace() { 309 if (!StdNamespace) { 310 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 311 DeclContext *Global = Context.getTranslationUnitDecl(); 312 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 313 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 314 } 315 return StdNamespace; 316} 317 318/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the same name 319/// and scope as a previous declaration 'Old'. Figure out how to resolve this 320/// situation, merging decls or emitting diagnostics as appropriate. 321/// 322TypedefDecl *Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 323 bool objc_types = false; 324 // Allow multiple definitions for ObjC built-in typedefs. 325 // FIXME: Verify the underlying types are equivalent! 326 if (getLangOptions().ObjC1) { 327 const IdentifierInfo *TypeID = New->getIdentifier(); 328 switch (TypeID->getLength()) { 329 default: break; 330 case 2: 331 if (!TypeID->isStr("id")) 332 break; 333 Context.setObjCIdType(New); 334 objc_types = true; 335 break; 336 case 5: 337 if (!TypeID->isStr("Class")) 338 break; 339 Context.setObjCClassType(New); 340 objc_types = true; 341 return New; 342 case 3: 343 if (!TypeID->isStr("SEL")) 344 break; 345 Context.setObjCSelType(New); 346 objc_types = true; 347 return New; 348 case 8: 349 if (!TypeID->isStr("Protocol")) 350 break; 351 Context.setObjCProtoType(New->getUnderlyingType()); 352 objc_types = true; 353 return New; 354 } 355 // Fall through - the typedef name was not a builtin type. 356 } 357 // Verify the old decl was also a type. 358 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 359 if (!Old) { 360 Diag(New->getLocation(), diag::err_redefinition_different_kind) 361 << New->getDeclName(); 362 if (!objc_types) 363 Diag(OldD->getLocation(), diag::note_previous_definition); 364 return New; 365 } 366 367 // Determine the "old" type we'll use for checking and diagnostics. 368 QualType OldType; 369 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 370 OldType = OldTypedef->getUnderlyingType(); 371 else 372 OldType = Context.getTypeDeclType(Old); 373 374 // If the typedef types are not identical, reject them in all languages and 375 // with any extensions enabled. 376 377 if (OldType != New->getUnderlyingType() && 378 Context.getCanonicalType(OldType) != 379 Context.getCanonicalType(New->getUnderlyingType())) { 380 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 381 << New->getUnderlyingType() << OldType; 382 if (!objc_types) 383 Diag(Old->getLocation(), diag::note_previous_definition); 384 return New; 385 } 386 if (objc_types) return New; 387 if (getLangOptions().Microsoft) return New; 388 389 // C++ [dcl.typedef]p2: 390 // In a given non-class scope, a typedef specifier can be used to 391 // redefine the name of any type declared in that scope to refer 392 // to the type to which it already refers. 393 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 394 return New; 395 396 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 397 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 398 // *either* declaration is in a system header. The code below implements 399 // this adhoc compatibility rule. FIXME: The following code will not 400 // work properly when compiling ".i" files (containing preprocessed output). 401 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 402 SourceManager &SrcMgr = Context.getSourceManager(); 403 if (SrcMgr.isInSystemHeader(Old->getLocation())) 404 return New; 405 if (SrcMgr.isInSystemHeader(New->getLocation())) 406 return New; 407 } 408 409 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 410 Diag(Old->getLocation(), diag::note_previous_definition); 411 return New; 412} 413 414/// DeclhasAttr - returns true if decl Declaration already has the target 415/// attribute. 416static bool DeclHasAttr(const Decl *decl, const Attr *target) { 417 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 418 if (attr->getKind() == target->getKind()) 419 return true; 420 421 return false; 422} 423 424/// MergeAttributes - append attributes from the Old decl to the New one. 425static void MergeAttributes(Decl *New, Decl *Old) { 426 Attr *attr = const_cast<Attr*>(Old->getAttrs()), *tmp; 427 428 while (attr) { 429 tmp = attr; 430 attr = attr->getNext(); 431 432 if (!DeclHasAttr(New, tmp)) { 433 tmp->setInherited(true); 434 New->addAttr(tmp); 435 } else { 436 tmp->setNext(0); 437 delete(tmp); 438 } 439 } 440 441 Old->invalidateAttrs(); 442} 443 444/// MergeFunctionDecl - We just parsed a function 'New' from 445/// declarator D which has the same name and scope as a previous 446/// declaration 'Old'. Figure out how to resolve this situation, 447/// merging decls or emitting diagnostics as appropriate. 448/// Redeclaration will be set true if this New is a redeclaration OldD. 449/// 450/// In C++, New and Old must be declarations that are not 451/// overloaded. Use IsOverload to determine whether New and Old are 452/// overloaded, and to select the Old declaration that New should be 453/// merged with. 454FunctionDecl * 455Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) { 456 assert(!isa<OverloadedFunctionDecl>(OldD) && 457 "Cannot merge with an overloaded function declaration"); 458 459 Redeclaration = false; 460 // Verify the old decl was also a function. 461 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 462 if (!Old) { 463 Diag(New->getLocation(), diag::err_redefinition_different_kind) 464 << New->getDeclName(); 465 Diag(OldD->getLocation(), diag::note_previous_definition); 466 return New; 467 } 468 469 // Determine whether the previous declaration was a definition, 470 // implicit declaration, or a declaration. 471 diag::kind PrevDiag; 472 if (Old->isThisDeclarationADefinition()) 473 PrevDiag = diag::note_previous_definition; 474 else if (Old->isImplicit()) 475 PrevDiag = diag::note_previous_implicit_declaration; 476 else 477 PrevDiag = diag::note_previous_declaration; 478 479 QualType OldQType = Context.getCanonicalType(Old->getType()); 480 QualType NewQType = Context.getCanonicalType(New->getType()); 481 482 if (getLangOptions().CPlusPlus) { 483 // (C++98 13.1p2): 484 // Certain function declarations cannot be overloaded: 485 // -- Function declarations that differ only in the return type 486 // cannot be overloaded. 487 QualType OldReturnType 488 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 489 QualType NewReturnType 490 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 491 if (OldReturnType != NewReturnType) { 492 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 493 Diag(Old->getLocation(), PrevDiag); 494 Redeclaration = true; 495 return New; 496 } 497 498 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 499 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 500 if (OldMethod && NewMethod) { 501 // -- Member function declarations with the same name and the 502 // same parameter types cannot be overloaded if any of them 503 // is a static member function declaration. 504 if (OldMethod->isStatic() || NewMethod->isStatic()) { 505 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 506 Diag(Old->getLocation(), PrevDiag); 507 return New; 508 } 509 510 // C++ [class.mem]p1: 511 // [...] A member shall not be declared twice in the 512 // member-specification, except that a nested class or member 513 // class template can be declared and then later defined. 514 if (OldMethod->getLexicalDeclContext() == 515 NewMethod->getLexicalDeclContext()) { 516 unsigned NewDiag; 517 if (isa<CXXConstructorDecl>(OldMethod)) 518 NewDiag = diag::err_constructor_redeclared; 519 else if (isa<CXXDestructorDecl>(NewMethod)) 520 NewDiag = diag::err_destructor_redeclared; 521 else if (isa<CXXConversionDecl>(NewMethod)) 522 NewDiag = diag::err_conv_function_redeclared; 523 else 524 NewDiag = diag::err_member_redeclared; 525 526 Diag(New->getLocation(), NewDiag); 527 Diag(Old->getLocation(), PrevDiag); 528 } 529 } 530 531 // (C++98 8.3.5p3): 532 // All declarations for a function shall agree exactly in both the 533 // return type and the parameter-type-list. 534 if (OldQType == NewQType) { 535 // We have a redeclaration. 536 MergeAttributes(New, Old); 537 Redeclaration = true; 538 return MergeCXXFunctionDecl(New, Old); 539 } 540 541 // Fall through for conflicting redeclarations and redefinitions. 542 } 543 544 // C: Function types need to be compatible, not identical. This handles 545 // duplicate function decls like "void f(int); void f(enum X);" properly. 546 if (!getLangOptions().CPlusPlus && 547 Context.typesAreCompatible(OldQType, NewQType)) { 548 MergeAttributes(New, Old); 549 Redeclaration = true; 550 return New; 551 } 552 553 // A function that has already been declared has been redeclared or defined 554 // with a different type- show appropriate diagnostic 555 556 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 557 // TODO: This is totally simplistic. It should handle merging functions 558 // together etc, merging extern int X; int X; ... 559 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 560 Diag(Old->getLocation(), PrevDiag); 561 return New; 562} 563 564/// Predicate for C "tentative" external object definitions (C99 6.9.2). 565static bool isTentativeDefinition(VarDecl *VD) { 566 if (VD->isFileVarDecl()) 567 return (!VD->getInit() && 568 (VD->getStorageClass() == VarDecl::None || 569 VD->getStorageClass() == VarDecl::Static)); 570 return false; 571} 572 573/// CheckForFileScopedRedefinitions - Make sure we forgo redefinition errors 574/// when dealing with C "tentative" external object definitions (C99 6.9.2). 575void Sema::CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD) { 576 bool VDIsTentative = isTentativeDefinition(VD); 577 bool VDIsIncompleteArray = VD->getType()->isIncompleteArrayType(); 578 579 // FIXME: I don't think this will actually see all of the 580 // redefinitions. Can't we check this property on-the-fly? 581 for (IdentifierResolver::iterator I = IdResolver.begin(VD->getIdentifier()), 582 E = IdResolver.end(); 583 I != E; ++I) { 584 if (*I != VD && isDeclInScope(*I, VD->getDeclContext(), S)) { 585 VarDecl *OldDecl = dyn_cast<VarDecl>(*I); 586 587 // Handle the following case: 588 // int a[10]; 589 // int a[]; - the code below makes sure we set the correct type. 590 // int a[11]; - this is an error, size isn't 10. 591 if (OldDecl && VDIsTentative && VDIsIncompleteArray && 592 OldDecl->getType()->isConstantArrayType()) 593 VD->setType(OldDecl->getType()); 594 595 // Check for "tentative" definitions. We can't accomplish this in 596 // MergeVarDecl since the initializer hasn't been attached. 597 if (!OldDecl || isTentativeDefinition(OldDecl) || VDIsTentative) 598 continue; 599 600 // Handle __private_extern__ just like extern. 601 if (OldDecl->getStorageClass() != VarDecl::Extern && 602 OldDecl->getStorageClass() != VarDecl::PrivateExtern && 603 VD->getStorageClass() != VarDecl::Extern && 604 VD->getStorageClass() != VarDecl::PrivateExtern) { 605 Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName(); 606 Diag(OldDecl->getLocation(), diag::note_previous_definition); 607 // One redefinition error is enough. 608 break; 609 } 610 } 611 } 612} 613 614/// MergeVarDecl - We just parsed a variable 'New' which has the same name 615/// and scope as a previous declaration 'Old'. Figure out how to resolve this 616/// situation, merging decls or emitting diagnostics as appropriate. 617/// 618/// Tentative definition rules (C99 6.9.2p2) are checked by 619/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 620/// definitions here, since the initializer hasn't been attached. 621/// 622VarDecl *Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 623 // Verify the old decl was also a variable. 624 VarDecl *Old = dyn_cast<VarDecl>(OldD); 625 if (!Old) { 626 Diag(New->getLocation(), diag::err_redefinition_different_kind) 627 << New->getDeclName(); 628 Diag(OldD->getLocation(), diag::note_previous_definition); 629 return New; 630 } 631 632 MergeAttributes(New, Old); 633 634 // Merge the types 635 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 636 if (MergedT.isNull()) { 637 Diag(New->getLocation(), diag::err_redefinition_different_type) 638 << New->getDeclName(); 639 Diag(Old->getLocation(), diag::note_previous_definition); 640 return New; 641 } 642 New->setType(MergedT); 643 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 644 if (New->getStorageClass() == VarDecl::Static && 645 (Old->getStorageClass() == VarDecl::None || 646 Old->getStorageClass() == VarDecl::Extern)) { 647 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 648 Diag(Old->getLocation(), diag::note_previous_definition); 649 return New; 650 } 651 // C99 6.2.2p4: Check if we have a non-static decl followed by a static. 652 if (New->getStorageClass() != VarDecl::Static && 653 Old->getStorageClass() == VarDecl::Static) { 654 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 655 Diag(Old->getLocation(), diag::note_previous_definition); 656 return New; 657 } 658 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 659 if (New->getStorageClass() != VarDecl::Extern && !New->isFileVarDecl()) { 660 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 661 Diag(Old->getLocation(), diag::note_previous_definition); 662 } 663 return New; 664} 665 666/// CheckParmsForFunctionDef - Check that the parameters of the given 667/// function are appropriate for the definition of a function. This 668/// takes care of any checks that cannot be performed on the 669/// declaration itself, e.g., that the types of each of the function 670/// parameters are complete. 671bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 672 bool HasInvalidParm = false; 673 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 674 ParmVarDecl *Param = FD->getParamDecl(p); 675 676 // C99 6.7.5.3p4: the parameters in a parameter type list in a 677 // function declarator that is part of a function definition of 678 // that function shall not have incomplete type. 679 if (!Param->isInvalidDecl() && 680 DiagnoseIncompleteType(Param->getLocation(), Param->getType(), 681 diag::err_typecheck_decl_incomplete_type)) { 682 Param->setInvalidDecl(); 683 HasInvalidParm = true; 684 } 685 686 // C99 6.9.1p5: If the declarator includes a parameter type list, the 687 // declaration of each parameter shall include an identifier. 688 if (Param->getIdentifier() == 0 && !getLangOptions().CPlusPlus) 689 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 690 } 691 692 return HasInvalidParm; 693} 694 695/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 696/// no declarator (e.g. "struct foo;") is parsed. 697Sema::DeclTy *Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 698 TagDecl *Tag = 0; 699 if (DS.getTypeSpecType() == DeclSpec::TST_class || 700 DS.getTypeSpecType() == DeclSpec::TST_struct || 701 DS.getTypeSpecType() == DeclSpec::TST_union || 702 DS.getTypeSpecType() == DeclSpec::TST_enum) 703 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 704 705 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 706 if (!Record->getDeclName() && Record->isDefinition() && 707 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) 708 return BuildAnonymousStructOrUnion(S, DS, Record); 709 710 // Microsoft allows unnamed struct/union fields. Don't complain 711 // about them. 712 // FIXME: Should we support Microsoft's extensions in this area? 713 if (Record->getDeclName() && getLangOptions().Microsoft) 714 return Tag; 715 } 716 717 if (!DS.isMissingDeclaratorOk() && 718 DS.getTypeSpecType() != DeclSpec::TST_error) { 719 // Warn about typedefs of enums without names, since this is an 720 // extension in both Microsoft an GNU. 721 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 722 Tag && isa<EnumDecl>(Tag)) { 723 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 724 << DS.getSourceRange(); 725 return Tag; 726 } 727 728 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 729 << DS.getSourceRange(); 730 return 0; 731 } 732 733 return Tag; 734} 735 736/// InjectAnonymousStructOrUnionMembers - Inject the members of the 737/// anonymous struct or union AnonRecord into the owning context Owner 738/// and scope S. This routine will be invoked just after we realize 739/// that an unnamed union or struct is actually an anonymous union or 740/// struct, e.g., 741/// 742/// @code 743/// union { 744/// int i; 745/// float f; 746/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 747/// // f into the surrounding scope.x 748/// @endcode 749/// 750/// This routine is recursive, injecting the names of nested anonymous 751/// structs/unions into the owning context and scope as well. 752bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 753 RecordDecl *AnonRecord) { 754 bool Invalid = false; 755 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 756 FEnd = AnonRecord->field_end(); 757 F != FEnd; ++F) { 758 if ((*F)->getDeclName()) { 759 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 760 LookupOrdinaryName, true); 761 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 762 // C++ [class.union]p2: 763 // The names of the members of an anonymous union shall be 764 // distinct from the names of any other entity in the 765 // scope in which the anonymous union is declared. 766 unsigned diagKind 767 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 768 : diag::err_anonymous_struct_member_redecl; 769 Diag((*F)->getLocation(), diagKind) 770 << (*F)->getDeclName(); 771 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 772 Invalid = true; 773 } else { 774 // C++ [class.union]p2: 775 // For the purpose of name lookup, after the anonymous union 776 // definition, the members of the anonymous union are 777 // considered to have been defined in the scope in which the 778 // anonymous union is declared. 779 Owner->makeDeclVisibleInContext(*F); 780 S->AddDecl(*F); 781 IdResolver.AddDecl(*F); 782 } 783 } else if (const RecordType *InnerRecordType 784 = (*F)->getType()->getAsRecordType()) { 785 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 786 if (InnerRecord->isAnonymousStructOrUnion()) 787 Invalid = Invalid || 788 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 789 } 790 } 791 792 return Invalid; 793} 794 795/// ActOnAnonymousStructOrUnion - Handle the declaration of an 796/// anonymous structure or union. Anonymous unions are a C++ feature 797/// (C++ [class.union]) and a GNU C extension; anonymous structures 798/// are a GNU C and GNU C++ extension. 799Sema::DeclTy *Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 800 RecordDecl *Record) { 801 DeclContext *Owner = Record->getDeclContext(); 802 803 // Diagnose whether this anonymous struct/union is an extension. 804 if (Record->isUnion() && !getLangOptions().CPlusPlus) 805 Diag(Record->getLocation(), diag::ext_anonymous_union); 806 else if (!Record->isUnion()) 807 Diag(Record->getLocation(), diag::ext_anonymous_struct); 808 809 // C and C++ require different kinds of checks for anonymous 810 // structs/unions. 811 bool Invalid = false; 812 if (getLangOptions().CPlusPlus) { 813 const char* PrevSpec = 0; 814 // C++ [class.union]p3: 815 // Anonymous unions declared in a named namespace or in the 816 // global namespace shall be declared static. 817 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 818 (isa<TranslationUnitDecl>(Owner) || 819 (isa<NamespaceDecl>(Owner) && 820 cast<NamespaceDecl>(Owner)->getDeclName()))) { 821 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 822 Invalid = true; 823 824 // Recover by adding 'static'. 825 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 826 } 827 // C++ [class.union]p3: 828 // A storage class is not allowed in a declaration of an 829 // anonymous union in a class scope. 830 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 831 isa<RecordDecl>(Owner)) { 832 Diag(DS.getStorageClassSpecLoc(), 833 diag::err_anonymous_union_with_storage_spec); 834 Invalid = true; 835 836 // Recover by removing the storage specifier. 837 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 838 PrevSpec); 839 } 840 841 // C++ [class.union]p2: 842 // The member-specification of an anonymous union shall only 843 // define non-static data members. [Note: nested types and 844 // functions cannot be declared within an anonymous union. ] 845 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 846 MemEnd = Record->decls_end(); 847 Mem != MemEnd; ++Mem) { 848 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 849 // C++ [class.union]p3: 850 // An anonymous union shall not have private or protected 851 // members (clause 11). 852 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 853 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 854 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 855 Invalid = true; 856 } 857 } else if ((*Mem)->isImplicit()) { 858 // Any implicit members are fine. 859 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 860 // This is a type that showed up in an 861 // elaborated-type-specifier inside the anonymous struct or 862 // union, but which actually declares a type outside of the 863 // anonymous struct or union. It's okay. 864 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 865 if (!MemRecord->isAnonymousStructOrUnion() && 866 MemRecord->getDeclName()) { 867 // This is a nested type declaration. 868 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 869 << (int)Record->isUnion(); 870 Invalid = true; 871 } 872 } else { 873 // We have something that isn't a non-static data 874 // member. Complain about it. 875 unsigned DK = diag::err_anonymous_record_bad_member; 876 if (isa<TypeDecl>(*Mem)) 877 DK = diag::err_anonymous_record_with_type; 878 else if (isa<FunctionDecl>(*Mem)) 879 DK = diag::err_anonymous_record_with_function; 880 else if (isa<VarDecl>(*Mem)) 881 DK = diag::err_anonymous_record_with_static; 882 Diag((*Mem)->getLocation(), DK) 883 << (int)Record->isUnion(); 884 Invalid = true; 885 } 886 } 887 } else { 888 // FIXME: Check GNU C semantics 889 if (Record->isUnion() && !Owner->isRecord()) { 890 Diag(Record->getLocation(), diag::err_anonymous_union_not_member) 891 << (int)getLangOptions().CPlusPlus; 892 Invalid = true; 893 } 894 } 895 896 if (!Record->isUnion() && !Owner->isRecord()) { 897 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 898 << (int)getLangOptions().CPlusPlus; 899 Invalid = true; 900 } 901 902 // Create a declaration for this anonymous struct/union. 903 NamedDecl *Anon = 0; 904 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 905 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 906 /*IdentifierInfo=*/0, 907 Context.getTypeDeclType(Record), 908 /*BitWidth=*/0, /*Mutable=*/false); 909 Anon->setAccess(AS_public); 910 if (getLangOptions().CPlusPlus) 911 FieldCollector->Add(cast<FieldDecl>(Anon)); 912 } else { 913 VarDecl::StorageClass SC; 914 switch (DS.getStorageClassSpec()) { 915 default: assert(0 && "Unknown storage class!"); 916 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 917 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 918 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 919 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 920 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 921 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 922 case DeclSpec::SCS_mutable: 923 // mutable can only appear on non-static class members, so it's always 924 // an error here 925 Diag(Record->getLocation(), diag::err_mutable_nonmember); 926 Invalid = true; 927 SC = VarDecl::None; 928 break; 929 } 930 931 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 932 /*IdentifierInfo=*/0, 933 Context.getTypeDeclType(Record), 934 SC, DS.getSourceRange().getBegin()); 935 } 936 Anon->setImplicit(); 937 938 // Add the anonymous struct/union object to the current 939 // context. We'll be referencing this object when we refer to one of 940 // its members. 941 Owner->addDecl(Anon); 942 943 // Inject the members of the anonymous struct/union into the owning 944 // context and into the identifier resolver chain for name lookup 945 // purposes. 946 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 947 Invalid = true; 948 949 // Mark this as an anonymous struct/union type. Note that we do not 950 // do this until after we have already checked and injected the 951 // members of this anonymous struct/union type, because otherwise 952 // the members could be injected twice: once by DeclContext when it 953 // builds its lookup table, and once by 954 // InjectAnonymousStructOrUnionMembers. 955 Record->setAnonymousStructOrUnion(true); 956 957 if (Invalid) 958 Anon->setInvalidDecl(); 959 960 return Anon; 961} 962 963bool Sema::CheckSingleInitializer(Expr *&Init, QualType DeclType, 964 bool DirectInit) { 965 // Get the type before calling CheckSingleAssignmentConstraints(), since 966 // it can promote the expression. 967 QualType InitType = Init->getType(); 968 969 if (getLangOptions().CPlusPlus) { 970 // FIXME: I dislike this error message. A lot. 971 if (PerformImplicitConversion(Init, DeclType, "initializing", DirectInit)) 972 return Diag(Init->getSourceRange().getBegin(), 973 diag::err_typecheck_convert_incompatible) 974 << DeclType << Init->getType() << "initializing" 975 << Init->getSourceRange(); 976 977 return false; 978 } 979 980 AssignConvertType ConvTy = CheckSingleAssignmentConstraints(DeclType, Init); 981 return DiagnoseAssignmentResult(ConvTy, Init->getLocStart(), DeclType, 982 InitType, Init, "initializing"); 983} 984 985bool Sema::CheckStringLiteralInit(StringLiteral *strLiteral, QualType &DeclT) { 986 const ArrayType *AT = Context.getAsArrayType(DeclT); 987 988 if (const IncompleteArrayType *IAT = dyn_cast<IncompleteArrayType>(AT)) { 989 // C99 6.7.8p14. We have an array of character type with unknown size 990 // being initialized to a string literal. 991 llvm::APSInt ConstVal(32); 992 ConstVal = strLiteral->getByteLength() + 1; 993 // Return a new array type (C99 6.7.8p22). 994 DeclT = Context.getConstantArrayType(IAT->getElementType(), ConstVal, 995 ArrayType::Normal, 0); 996 } else { 997 const ConstantArrayType *CAT = cast<ConstantArrayType>(AT); 998 // C99 6.7.8p14. We have an array of character type with known size. 999 // FIXME: Avoid truncation for 64-bit length strings. 1000 if (strLiteral->getByteLength() > (unsigned)CAT->getSize().getZExtValue()) 1001 Diag(strLiteral->getSourceRange().getBegin(), 1002 diag::warn_initializer_string_for_char_array_too_long) 1003 << strLiteral->getSourceRange(); 1004 } 1005 // Set type from "char *" to "constant array of char". 1006 strLiteral->setType(DeclT); 1007 // For now, we always return false (meaning success). 1008 return false; 1009} 1010 1011StringLiteral *Sema::IsStringLiteralInit(Expr *Init, QualType DeclType) { 1012 const ArrayType *AT = Context.getAsArrayType(DeclType); 1013 if (AT && AT->getElementType()->isCharType()) { 1014 return dyn_cast<StringLiteral>(Init->IgnoreParens()); 1015 } 1016 return 0; 1017} 1018 1019bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType, 1020 SourceLocation InitLoc, 1021 DeclarationName InitEntity, 1022 bool DirectInit) { 1023 if (DeclType->isDependentType() || Init->isTypeDependent()) 1024 return false; 1025 1026 // C++ [dcl.init.ref]p1: 1027 // A variable declared to be a T&, that is "reference to type T" 1028 // (8.3.2), shall be initialized by an object, or function, of 1029 // type T or by an object that can be converted into a T. 1030 if (DeclType->isReferenceType()) 1031 return CheckReferenceInit(Init, DeclType, 0, false, DirectInit); 1032 1033 // C99 6.7.8p3: The type of the entity to be initialized shall be an array 1034 // of unknown size ("[]") or an object type that is not a variable array type. 1035 if (const VariableArrayType *VAT = Context.getAsVariableArrayType(DeclType)) 1036 return Diag(InitLoc, diag::err_variable_object_no_init) 1037 << VAT->getSizeExpr()->getSourceRange(); 1038 1039 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 1040 if (!InitList) { 1041 // FIXME: Handle wide strings 1042 if (StringLiteral *strLiteral = IsStringLiteralInit(Init, DeclType)) 1043 return CheckStringLiteralInit(strLiteral, DeclType); 1044 1045 // C++ [dcl.init]p14: 1046 // -- If the destination type is a (possibly cv-qualified) class 1047 // type: 1048 if (getLangOptions().CPlusPlus && DeclType->isRecordType()) { 1049 QualType DeclTypeC = Context.getCanonicalType(DeclType); 1050 QualType InitTypeC = Context.getCanonicalType(Init->getType()); 1051 1052 // -- If the initialization is direct-initialization, or if it is 1053 // copy-initialization where the cv-unqualified version of the 1054 // source type is the same class as, or a derived class of, the 1055 // class of the destination, constructors are considered. 1056 if ((DeclTypeC.getUnqualifiedType() == InitTypeC.getUnqualifiedType()) || 1057 IsDerivedFrom(InitTypeC, DeclTypeC)) { 1058 CXXConstructorDecl *Constructor 1059 = PerformInitializationByConstructor(DeclType, &Init, 1, 1060 InitLoc, Init->getSourceRange(), 1061 InitEntity, 1062 DirectInit? IK_Direct : IK_Copy); 1063 return Constructor == 0; 1064 } 1065 1066 // -- Otherwise (i.e., for the remaining copy-initialization 1067 // cases), user-defined conversion sequences that can 1068 // convert from the source type to the destination type or 1069 // (when a conversion function is used) to a derived class 1070 // thereof are enumerated as described in 13.3.1.4, and the 1071 // best one is chosen through overload resolution 1072 // (13.3). If the conversion cannot be done or is 1073 // ambiguous, the initialization is ill-formed. The 1074 // function selected is called with the initializer 1075 // expression as its argument; if the function is a 1076 // constructor, the call initializes a temporary of the 1077 // destination type. 1078 // FIXME: We're pretending to do copy elision here; return to 1079 // this when we have ASTs for such things. 1080 if (!PerformImplicitConversion(Init, DeclType, "initializing")) 1081 return false; 1082 1083 if (InitEntity) 1084 return Diag(InitLoc, diag::err_cannot_initialize_decl) 1085 << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1086 << Init->getType() << Init->getSourceRange(); 1087 else 1088 return Diag(InitLoc, diag::err_cannot_initialize_decl_noname) 1089 << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid) 1090 << Init->getType() << Init->getSourceRange(); 1091 } 1092 1093 // C99 6.7.8p16. 1094 if (DeclType->isArrayType()) 1095 return Diag(Init->getLocStart(), diag::err_array_init_list_required) 1096 << Init->getSourceRange(); 1097 1098 return CheckSingleInitializer(Init, DeclType, DirectInit); 1099 } 1100 1101 bool hadError = CheckInitList(InitList, DeclType); 1102 Init = InitList; 1103 return hadError; 1104} 1105 1106/// GetNameForDeclarator - Determine the full declaration name for the 1107/// given Declarator. 1108DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1109 switch (D.getKind()) { 1110 case Declarator::DK_Abstract: 1111 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1112 return DeclarationName(); 1113 1114 case Declarator::DK_Normal: 1115 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1116 return DeclarationName(D.getIdentifier()); 1117 1118 case Declarator::DK_Constructor: { 1119 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1120 Ty = Context.getCanonicalType(Ty); 1121 return Context.DeclarationNames.getCXXConstructorName(Ty); 1122 } 1123 1124 case Declarator::DK_Destructor: { 1125 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1126 Ty = Context.getCanonicalType(Ty); 1127 return Context.DeclarationNames.getCXXDestructorName(Ty); 1128 } 1129 1130 case Declarator::DK_Conversion: { 1131 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1132 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1133 Ty = Context.getCanonicalType(Ty); 1134 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1135 } 1136 1137 case Declarator::DK_Operator: 1138 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1139 return Context.DeclarationNames.getCXXOperatorName( 1140 D.getOverloadedOperator()); 1141 } 1142 1143 assert(false && "Unknown name kind"); 1144 return DeclarationName(); 1145} 1146 1147/// isNearlyMatchingFunction - Determine whether the C++ functions 1148/// Declaration and Definition are "nearly" matching. This heuristic 1149/// is used to improve diagnostics in the case where an out-of-line 1150/// function definition doesn't match any declaration within 1151/// the class or namespace. 1152static bool isNearlyMatchingFunction(ASTContext &Context, 1153 FunctionDecl *Declaration, 1154 FunctionDecl *Definition) { 1155 if (Declaration->param_size() != Definition->param_size()) 1156 return false; 1157 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1158 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1159 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1160 1161 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1162 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1163 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1164 return false; 1165 } 1166 1167 return true; 1168} 1169 1170Sema::DeclTy * 1171Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl, 1172 bool IsFunctionDefinition) { 1173 NamedDecl *LastDeclarator = dyn_cast_or_null<NamedDecl>((Decl *)lastDecl); 1174 DeclarationName Name = GetNameForDeclarator(D); 1175 1176 // All of these full declarators require an identifier. If it doesn't have 1177 // one, the ParsedFreeStandingDeclSpec action should be used. 1178 if (!Name) { 1179 if (!D.getInvalidType()) // Reject this if we think it is valid. 1180 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1181 diag::err_declarator_need_ident) 1182 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1183 return 0; 1184 } 1185 1186 // The scope passed in may not be a decl scope. Zip up the scope tree until 1187 // we find one that is. 1188 while ((S->getFlags() & Scope::DeclScope) == 0 || 1189 (S->getFlags() & Scope::TemplateParamScope) != 0) 1190 S = S->getParent(); 1191 1192 DeclContext *DC; 1193 NamedDecl *PrevDecl; 1194 NamedDecl *New; 1195 bool InvalidDecl = false; 1196 1197 // See if this is a redefinition of a variable in the same scope. 1198 if (!D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid()) { 1199 DC = CurContext; 1200 PrevDecl = LookupName(S, Name, LookupOrdinaryName); 1201 } else { // Something like "int foo::x;" 1202 DC = static_cast<DeclContext*>(D.getCXXScopeSpec().getScopeRep()); 1203 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName); 1204 1205 // C++ 7.3.1.2p2: 1206 // Members (including explicit specializations of templates) of a named 1207 // namespace can also be defined outside that namespace by explicit 1208 // qualification of the name being defined, provided that the entity being 1209 // defined was already declared in the namespace and the definition appears 1210 // after the point of declaration in a namespace that encloses the 1211 // declarations namespace. 1212 // 1213 // Note that we only check the context at this point. We don't yet 1214 // have enough information to make sure that PrevDecl is actually 1215 // the declaration we want to match. For example, given: 1216 // 1217 // class X { 1218 // void f(); 1219 // void f(float); 1220 // }; 1221 // 1222 // void X::f(int) { } // ill-formed 1223 // 1224 // In this case, PrevDecl will point to the overload set 1225 // containing the two f's declared in X, but neither of them 1226 // matches. 1227 1228 // First check whether we named the global scope. 1229 if (isa<TranslationUnitDecl>(DC)) { 1230 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1231 << Name << D.getCXXScopeSpec().getRange(); 1232 } else if (!CurContext->Encloses(DC)) { 1233 // The qualifying scope doesn't enclose the original declaration. 1234 // Emit diagnostic based on current scope. 1235 SourceLocation L = D.getIdentifierLoc(); 1236 SourceRange R = D.getCXXScopeSpec().getRange(); 1237 if (isa<FunctionDecl>(CurContext)) 1238 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1239 else 1240 Diag(L, diag::err_invalid_declarator_scope) 1241 << Name << cast<NamedDecl>(DC) << R; 1242 InvalidDecl = true; 1243 } 1244 } 1245 1246 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1247 // Maybe we will complain about the shadowed template parameter. 1248 InvalidDecl = InvalidDecl 1249 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1250 // Just pretend that we didn't see the previous declaration. 1251 PrevDecl = 0; 1252 } 1253 1254 // In C++, the previous declaration we find might be a tag type 1255 // (class or enum). In this case, the new declaration will hide the 1256 // tag type. Note that this does does not apply if we're declaring a 1257 // typedef (C++ [dcl.typedef]p4). 1258 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1259 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1260 PrevDecl = 0; 1261 1262 QualType R = GetTypeForDeclarator(D, S); 1263 assert(!R.isNull() && "GetTypeForDeclarator() returned null type"); 1264 1265 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1266 New = ActOnTypedefDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1267 InvalidDecl); 1268 } else if (R.getTypePtr()->isFunctionType()) { 1269 New = ActOnFunctionDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1270 IsFunctionDefinition, InvalidDecl); 1271 } else { 1272 New = ActOnVariableDeclarator(S, D, DC, R, LastDeclarator, PrevDecl, 1273 InvalidDecl); 1274 } 1275 1276 if (New == 0) 1277 return 0; 1278 1279 // Set the lexical context. If the declarator has a C++ scope specifier, the 1280 // lexical context will be different from the semantic context. 1281 New->setLexicalDeclContext(CurContext); 1282 1283 // If this has an identifier, add it to the scope stack. 1284 if (Name) 1285 PushOnScopeChains(New, S); 1286 // If any semantic error occurred, mark the decl as invalid. 1287 if (D.getInvalidType() || InvalidDecl) 1288 New->setInvalidDecl(); 1289 1290 return New; 1291} 1292 1293NamedDecl* 1294Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1295 QualType R, Decl* LastDeclarator, 1296 Decl* PrevDecl, bool& InvalidDecl) { 1297 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1298 if (D.getCXXScopeSpec().isSet()) { 1299 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1300 << D.getCXXScopeSpec().getRange(); 1301 InvalidDecl = true; 1302 // Pretend we didn't see the scope specifier. 1303 DC = 0; 1304 } 1305 1306 // Check that there are no default arguments (C++ only). 1307 if (getLangOptions().CPlusPlus) 1308 CheckExtraCXXDefaultArguments(D); 1309 1310 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, LastDeclarator); 1311 if (!NewTD) return 0; 1312 1313 // Handle attributes prior to checking for duplicates in MergeVarDecl 1314 ProcessDeclAttributes(NewTD, D); 1315 // Merge the decl with the existing one if appropriate. If the decl is 1316 // in an outer scope, it isn't the same thing. 1317 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1318 NewTD = MergeTypeDefDecl(NewTD, PrevDecl); 1319 if (NewTD == 0) return 0; 1320 } 1321 1322 if (S->getFnParent() == 0) { 1323 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1324 // then it shall have block scope. 1325 if (NewTD->getUnderlyingType()->isVariablyModifiedType()) { 1326 if (NewTD->getUnderlyingType()->isVariableArrayType()) 1327 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1328 else 1329 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1330 1331 InvalidDecl = true; 1332 } 1333 } 1334 return NewTD; 1335} 1336 1337NamedDecl* 1338Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1339 QualType R, Decl* LastDeclarator, 1340 Decl* PrevDecl, bool& InvalidDecl) { 1341 DeclarationName Name = GetNameForDeclarator(D); 1342 1343 // Check that there are no default arguments (C++ only). 1344 if (getLangOptions().CPlusPlus) 1345 CheckExtraCXXDefaultArguments(D); 1346 1347 if (R.getTypePtr()->isObjCInterfaceType()) { 1348 Diag(D.getIdentifierLoc(), diag::err_statically_allocated_object) 1349 << D.getIdentifier(); 1350 InvalidDecl = true; 1351 } 1352 1353 VarDecl *NewVD; 1354 VarDecl::StorageClass SC; 1355 switch (D.getDeclSpec().getStorageClassSpec()) { 1356 default: assert(0 && "Unknown storage class!"); 1357 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1358 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1359 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1360 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1361 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1362 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1363 case DeclSpec::SCS_mutable: 1364 // mutable can only appear on non-static class members, so it's always 1365 // an error here 1366 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1367 InvalidDecl = true; 1368 SC = VarDecl::None; 1369 break; 1370 } 1371 1372 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1373 if (!II) { 1374 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1375 << Name.getAsString(); 1376 return 0; 1377 } 1378 1379 if (DC->isRecord()) { 1380 // This is a static data member for a C++ class. 1381 NewVD = CXXClassVarDecl::Create(Context, cast<CXXRecordDecl>(DC), 1382 D.getIdentifierLoc(), II, 1383 R); 1384 } else { 1385 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1386 if (S->getFnParent() == 0) { 1387 // C99 6.9p2: The storage-class specifiers auto and register shall not 1388 // appear in the declaration specifiers in an external declaration. 1389 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1390 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1391 InvalidDecl = true; 1392 } 1393 } 1394 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1395 II, R, SC, 1396 // FIXME: Move to DeclGroup... 1397 D.getDeclSpec().getSourceRange().getBegin()); 1398 NewVD->setThreadSpecified(ThreadSpecified); 1399 } 1400 NewVD->setNextDeclarator(LastDeclarator); 1401 1402 // Handle attributes prior to checking for duplicates in MergeVarDecl 1403 ProcessDeclAttributes(NewVD, D); 1404 1405 // Handle GNU asm-label extension (encoded as an attribute). 1406 if (Expr *E = (Expr*) D.getAsmLabel()) { 1407 // The parser guarantees this is a string. 1408 StringLiteral *SE = cast<StringLiteral>(E); 1409 NewVD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1410 SE->getByteLength()))); 1411 } 1412 1413 // Emit an error if an address space was applied to decl with local storage. 1414 // This includes arrays of objects with address space qualifiers, but not 1415 // automatic variables that point to other address spaces. 1416 // ISO/IEC TR 18037 S5.1.2 1417 if (NewVD->hasLocalStorage() && (NewVD->getType().getAddressSpace() != 0)) { 1418 Diag(D.getIdentifierLoc(), diag::err_as_qualified_auto_decl); 1419 InvalidDecl = true; 1420 } 1421 // Merge the decl with the existing one if appropriate. If the decl is 1422 // in an outer scope, it isn't the same thing. 1423 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1424 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1425 // The user tried to define a non-static data member 1426 // out-of-line (C++ [dcl.meaning]p1). 1427 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1428 << D.getCXXScopeSpec().getRange(); 1429 NewVD->Destroy(Context); 1430 return 0; 1431 } 1432 1433 NewVD = MergeVarDecl(NewVD, PrevDecl); 1434 if (NewVD == 0) return 0; 1435 1436 if (D.getCXXScopeSpec().isSet()) { 1437 // No previous declaration in the qualifying scope. 1438 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1439 << Name << D.getCXXScopeSpec().getRange(); 1440 InvalidDecl = true; 1441 } 1442 } 1443 return NewVD; 1444} 1445 1446NamedDecl* 1447Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1448 QualType R, Decl *LastDeclarator, 1449 Decl* PrevDecl, bool IsFunctionDefinition, 1450 bool& InvalidDecl) { 1451 assert(R.getTypePtr()->isFunctionType()); 1452 1453 DeclarationName Name = GetNameForDeclarator(D); 1454 FunctionDecl::StorageClass SC = FunctionDecl::None; 1455 switch (D.getDeclSpec().getStorageClassSpec()) { 1456 default: assert(0 && "Unknown storage class!"); 1457 case DeclSpec::SCS_auto: 1458 case DeclSpec::SCS_register: 1459 case DeclSpec::SCS_mutable: 1460 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_func); 1461 InvalidDecl = true; 1462 break; 1463 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1464 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1465 case DeclSpec::SCS_static: SC = FunctionDecl::Static; break; 1466 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1467 } 1468 1469 bool isInline = D.getDeclSpec().isInlineSpecified(); 1470 // bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1471 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1472 1473 FunctionDecl *NewFD; 1474 if (D.getKind() == Declarator::DK_Constructor) { 1475 // This is a C++ constructor declaration. 1476 assert(DC->isRecord() && 1477 "Constructors can only be declared in a member context"); 1478 1479 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1480 1481 // Create the new declaration 1482 NewFD = CXXConstructorDecl::Create(Context, 1483 cast<CXXRecordDecl>(DC), 1484 D.getIdentifierLoc(), Name, R, 1485 isExplicit, isInline, 1486 /*isImplicitlyDeclared=*/false); 1487 1488 if (InvalidDecl) 1489 NewFD->setInvalidDecl(); 1490 } else if (D.getKind() == Declarator::DK_Destructor) { 1491 // This is a C++ destructor declaration. 1492 if (DC->isRecord()) { 1493 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1494 1495 NewFD = CXXDestructorDecl::Create(Context, 1496 cast<CXXRecordDecl>(DC), 1497 D.getIdentifierLoc(), Name, R, 1498 isInline, 1499 /*isImplicitlyDeclared=*/false); 1500 1501 if (InvalidDecl) 1502 NewFD->setInvalidDecl(); 1503 } else { 1504 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1505 1506 // Create a FunctionDecl to satisfy the function definition parsing 1507 // code path. 1508 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1509 Name, R, SC, isInline, 1510 // FIXME: Move to DeclGroup... 1511 D.getDeclSpec().getSourceRange().getBegin()); 1512 InvalidDecl = true; 1513 NewFD->setInvalidDecl(); 1514 } 1515 } else if (D.getKind() == Declarator::DK_Conversion) { 1516 if (!DC->isRecord()) { 1517 Diag(D.getIdentifierLoc(), 1518 diag::err_conv_function_not_member); 1519 return 0; 1520 } else { 1521 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1522 1523 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1524 D.getIdentifierLoc(), Name, R, 1525 isInline, isExplicit); 1526 1527 if (InvalidDecl) 1528 NewFD->setInvalidDecl(); 1529 } 1530 } else if (DC->isRecord()) { 1531 // This is a C++ method declaration. 1532 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1533 D.getIdentifierLoc(), Name, R, 1534 (SC == FunctionDecl::Static), isInline); 1535 } else { 1536 NewFD = FunctionDecl::Create(Context, DC, 1537 D.getIdentifierLoc(), 1538 Name, R, SC, isInline, 1539 // FIXME: Move to DeclGroup... 1540 D.getDeclSpec().getSourceRange().getBegin()); 1541 } 1542 NewFD->setNextDeclarator(LastDeclarator); 1543 1544 // Set the lexical context. If the declarator has a C++ 1545 // scope specifier, the lexical context will be different 1546 // from the semantic context. 1547 NewFD->setLexicalDeclContext(CurContext); 1548 1549 // Handle GNU asm-label extension (encoded as an attribute). 1550 if (Expr *E = (Expr*) D.getAsmLabel()) { 1551 // The parser guarantees this is a string. 1552 StringLiteral *SE = cast<StringLiteral>(E); 1553 NewFD->addAttr(new AsmLabelAttr(std::string(SE->getStrData(), 1554 SE->getByteLength()))); 1555 } 1556 1557 // Copy the parameter declarations from the declarator D to 1558 // the function declaration NewFD, if they are available. 1559 if (D.getNumTypeObjects() > 0) { 1560 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1561 1562 // Create Decl objects for each parameter, adding them to the 1563 // FunctionDecl. 1564 llvm::SmallVector<ParmVarDecl*, 16> Params; 1565 1566 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 1567 // function that takes no arguments, not a function that takes a 1568 // single void argument. 1569 // We let through "const void" here because Sema::GetTypeForDeclarator 1570 // already checks for that case. 1571 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1572 FTI.ArgInfo[0].Param && 1573 ((ParmVarDecl*)FTI.ArgInfo[0].Param)->getType()->isVoidType()) { 1574 // empty arg list, don't push any params. 1575 ParmVarDecl *Param = (ParmVarDecl*)FTI.ArgInfo[0].Param; 1576 1577 // In C++, the empty parameter-type-list must be spelled "void"; a 1578 // typedef of void is not permitted. 1579 if (getLangOptions().CPlusPlus && 1580 Param->getType().getUnqualifiedType() != Context.VoidTy) { 1581 Diag(Param->getLocation(), diag::ext_param_typedef_of_void); 1582 } 1583 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 1584 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 1585 Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 1586 } 1587 1588 NewFD->setParams(Context, &Params[0], Params.size()); 1589 } else if (R->getAsTypedefType()) { 1590 // When we're declaring a function with a typedef, as in the 1591 // following example, we'll need to synthesize (unnamed) 1592 // parameters for use in the declaration. 1593 // 1594 // @code 1595 // typedef void fn(int); 1596 // fn f; 1597 // @endcode 1598 const FunctionTypeProto *FT = R->getAsFunctionTypeProto(); 1599 if (!FT) { 1600 // This is a typedef of a function with no prototype, so we 1601 // don't need to do anything. 1602 } else if ((FT->getNumArgs() == 0) || 1603 (FT->getNumArgs() == 1 && !FT->isVariadic() && 1604 FT->getArgType(0)->isVoidType())) { 1605 // This is a zero-argument function. We don't need to do anything. 1606 } else { 1607 // Synthesize a parameter for each argument type. 1608 llvm::SmallVector<ParmVarDecl*, 16> Params; 1609 for (FunctionTypeProto::arg_type_iterator ArgType = FT->arg_type_begin(); 1610 ArgType != FT->arg_type_end(); ++ArgType) { 1611 Params.push_back(ParmVarDecl::Create(Context, DC, 1612 SourceLocation(), 0, 1613 *ArgType, VarDecl::None, 1614 0)); 1615 } 1616 1617 NewFD->setParams(Context, &Params[0], Params.size()); 1618 } 1619 } 1620 1621 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 1622 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 1623 else if (isa<CXXDestructorDecl>(NewFD)) { 1624 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 1625 Record->setUserDeclaredDestructor(true); 1626 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 1627 // user-defined destructor. 1628 Record->setPOD(false); 1629 } else if (CXXConversionDecl *Conversion = 1630 dyn_cast<CXXConversionDecl>(NewFD)) 1631 ActOnConversionDeclarator(Conversion); 1632 1633 // Extra checking for C++ overloaded operators (C++ [over.oper]). 1634 if (NewFD->isOverloadedOperator() && 1635 CheckOverloadedOperatorDeclaration(NewFD)) 1636 NewFD->setInvalidDecl(); 1637 1638 // Merge the decl with the existing one if appropriate. Since C functions 1639 // are in a flat namespace, make sure we consider decls in outer scopes. 1640 bool Redeclaration = false; 1641 if (PrevDecl && 1642 (!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, DC, S))) { 1643 // If C++, determine whether NewFD is an overload of PrevDecl or 1644 // a declaration that requires merging. If it's an overload, 1645 // there's no more work to do here; we'll just add the new 1646 // function to the scope. 1647 OverloadedFunctionDecl::function_iterator MatchedDecl; 1648 if (!getLangOptions().CPlusPlus || 1649 !IsOverload(NewFD, PrevDecl, MatchedDecl)) { 1650 Decl *OldDecl = PrevDecl; 1651 1652 // If PrevDecl was an overloaded function, extract the 1653 // FunctionDecl that matched. 1654 if (isa<OverloadedFunctionDecl>(PrevDecl)) 1655 OldDecl = *MatchedDecl; 1656 1657 // NewFD and PrevDecl represent declarations that need to be 1658 // merged. 1659 NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration); 1660 1661 if (NewFD == 0) return 0; 1662 if (Redeclaration) { 1663 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 1664 1665 // An out-of-line member function declaration must also be a 1666 // definition (C++ [dcl.meaning]p1). 1667 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && 1668 !InvalidDecl) { 1669 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1670 << D.getCXXScopeSpec().getRange(); 1671 NewFD->setInvalidDecl(); 1672 } 1673 } 1674 } 1675 } 1676 1677 if (D.getCXXScopeSpec().isSet() && 1678 (!PrevDecl || !Redeclaration)) { 1679 // The user tried to provide an out-of-line definition for a 1680 // function that is a member of a class or namespace, but there 1681 // was no such member function declared (C++ [class.mfct]p2, 1682 // C++ [namespace.memdef]p2). For example: 1683 // 1684 // class X { 1685 // void f() const; 1686 // }; 1687 // 1688 // void X::f() { } // ill-formed 1689 // 1690 // Complain about this problem, and attempt to suggest close 1691 // matches (e.g., those that differ only in cv-qualifiers and 1692 // whether the parameter types are references). 1693 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 1694 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 1695 InvalidDecl = true; 1696 1697 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 1698 true); 1699 assert(!Prev.isAmbiguous() && 1700 "Cannot have an ambiguity in previous-declaration lookup"); 1701 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 1702 Func != FuncEnd; ++Func) { 1703 if (isa<FunctionDecl>(*Func) && 1704 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 1705 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 1706 } 1707 1708 PrevDecl = 0; 1709 } 1710 1711 // Handle attributes. We need to have merged decls when handling attributes 1712 // (for example to check for conflicts, etc). 1713 ProcessDeclAttributes(NewFD, D); 1714 1715 if (getLangOptions().CPlusPlus) { 1716 // In C++, check default arguments now that we have merged decls. Unless 1717 // the lexical context is the class, because in this case this is done 1718 // during delayed parsing anyway. 1719 if (!CurContext->isRecord()) 1720 CheckCXXDefaultArguments(NewFD); 1721 1722 // An out-of-line member function declaration must also be a 1723 // definition (C++ [dcl.meaning]p1). 1724 if (!IsFunctionDefinition && D.getCXXScopeSpec().isSet() && !InvalidDecl) { 1725 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 1726 << D.getCXXScopeSpec().getRange(); 1727 InvalidDecl = true; 1728 } 1729 } 1730 return NewFD; 1731} 1732 1733void Sema::InitializerElementNotConstant(const Expr *Init) { 1734 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 1735 << Init->getSourceRange(); 1736} 1737 1738bool Sema::CheckAddressConstantExpressionLValue(const Expr* Init) { 1739 switch (Init->getStmtClass()) { 1740 default: 1741 InitializerElementNotConstant(Init); 1742 return true; 1743 case Expr::ParenExprClass: { 1744 const ParenExpr* PE = cast<ParenExpr>(Init); 1745 return CheckAddressConstantExpressionLValue(PE->getSubExpr()); 1746 } 1747 case Expr::CompoundLiteralExprClass: 1748 return cast<CompoundLiteralExpr>(Init)->isFileScope(); 1749 case Expr::DeclRefExprClass: 1750 case Expr::QualifiedDeclRefExprClass: { 1751 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 1752 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1753 if (VD->hasGlobalStorage()) 1754 return false; 1755 InitializerElementNotConstant(Init); 1756 return true; 1757 } 1758 if (isa<FunctionDecl>(D)) 1759 return false; 1760 InitializerElementNotConstant(Init); 1761 return true; 1762 } 1763 case Expr::MemberExprClass: { 1764 const MemberExpr *M = cast<MemberExpr>(Init); 1765 if (M->isArrow()) 1766 return CheckAddressConstantExpression(M->getBase()); 1767 return CheckAddressConstantExpressionLValue(M->getBase()); 1768 } 1769 case Expr::ArraySubscriptExprClass: { 1770 // FIXME: Should we pedwarn for "x[0+0]" (where x is a pointer)? 1771 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(Init); 1772 return CheckAddressConstantExpression(ASE->getBase()) || 1773 CheckArithmeticConstantExpression(ASE->getIdx()); 1774 } 1775 case Expr::StringLiteralClass: 1776 case Expr::PredefinedExprClass: 1777 return false; 1778 case Expr::UnaryOperatorClass: { 1779 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1780 1781 // C99 6.6p9 1782 if (Exp->getOpcode() == UnaryOperator::Deref) 1783 return CheckAddressConstantExpression(Exp->getSubExpr()); 1784 1785 InitializerElementNotConstant(Init); 1786 return true; 1787 } 1788 } 1789} 1790 1791bool Sema::CheckAddressConstantExpression(const Expr* Init) { 1792 switch (Init->getStmtClass()) { 1793 default: 1794 InitializerElementNotConstant(Init); 1795 return true; 1796 case Expr::ParenExprClass: 1797 return CheckAddressConstantExpression(cast<ParenExpr>(Init)->getSubExpr()); 1798 case Expr::StringLiteralClass: 1799 case Expr::ObjCStringLiteralClass: 1800 return false; 1801 case Expr::CallExprClass: 1802 case Expr::CXXOperatorCallExprClass: 1803 // __builtin___CFStringMakeConstantString is a valid constant l-value. 1804 if (cast<CallExpr>(Init)->isBuiltinCall() == 1805 Builtin::BI__builtin___CFStringMakeConstantString) 1806 return false; 1807 1808 InitializerElementNotConstant(Init); 1809 return true; 1810 1811 case Expr::UnaryOperatorClass: { 1812 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 1813 1814 // C99 6.6p9 1815 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1816 return CheckAddressConstantExpressionLValue(Exp->getSubExpr()); 1817 1818 if (Exp->getOpcode() == UnaryOperator::Extension) 1819 return CheckAddressConstantExpression(Exp->getSubExpr()); 1820 1821 InitializerElementNotConstant(Init); 1822 return true; 1823 } 1824 case Expr::BinaryOperatorClass: { 1825 // FIXME: Should we pedwarn for expressions like "a + 1 + 2"? 1826 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 1827 1828 Expr *PExp = Exp->getLHS(); 1829 Expr *IExp = Exp->getRHS(); 1830 if (IExp->getType()->isPointerType()) 1831 std::swap(PExp, IExp); 1832 1833 // FIXME: Should we pedwarn if IExp isn't an integer constant expression? 1834 return CheckAddressConstantExpression(PExp) || 1835 CheckArithmeticConstantExpression(IExp); 1836 } 1837 case Expr::ImplicitCastExprClass: 1838 case Expr::CStyleCastExprClass: { 1839 const Expr* SubExpr = cast<CastExpr>(Init)->getSubExpr(); 1840 if (Init->getStmtClass() == Expr::ImplicitCastExprClass) { 1841 // Check for implicit promotion 1842 if (SubExpr->getType()->isFunctionType() || 1843 SubExpr->getType()->isArrayType()) 1844 return CheckAddressConstantExpressionLValue(SubExpr); 1845 } 1846 1847 // Check for pointer->pointer cast 1848 if (SubExpr->getType()->isPointerType()) 1849 return CheckAddressConstantExpression(SubExpr); 1850 1851 if (SubExpr->getType()->isIntegralType()) { 1852 // Check for the special-case of a pointer->int->pointer cast; 1853 // this isn't standard, but some code requires it. See 1854 // PR2720 for an example. 1855 if (const CastExpr* SubCast = dyn_cast<CastExpr>(SubExpr)) { 1856 if (SubCast->getSubExpr()->getType()->isPointerType()) { 1857 unsigned IntWidth = Context.getIntWidth(SubCast->getType()); 1858 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 1859 if (IntWidth >= PointerWidth) { 1860 return CheckAddressConstantExpression(SubCast->getSubExpr()); 1861 } 1862 } 1863 } 1864 } 1865 if (SubExpr->getType()->isArithmeticType()) { 1866 return CheckArithmeticConstantExpression(SubExpr); 1867 } 1868 1869 InitializerElementNotConstant(Init); 1870 return true; 1871 } 1872 case Expr::ConditionalOperatorClass: { 1873 // FIXME: Should we pedwarn here? 1874 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 1875 if (!Exp->getCond()->getType()->isArithmeticType()) { 1876 InitializerElementNotConstant(Init); 1877 return true; 1878 } 1879 if (CheckArithmeticConstantExpression(Exp->getCond())) 1880 return true; 1881 if (Exp->getLHS() && 1882 CheckAddressConstantExpression(Exp->getLHS())) 1883 return true; 1884 return CheckAddressConstantExpression(Exp->getRHS()); 1885 } 1886 case Expr::AddrLabelExprClass: 1887 return false; 1888 } 1889} 1890 1891static const Expr* FindExpressionBaseAddress(const Expr* E); 1892 1893static const Expr* FindExpressionBaseAddressLValue(const Expr* E) { 1894 switch (E->getStmtClass()) { 1895 default: 1896 return E; 1897 case Expr::ParenExprClass: { 1898 const ParenExpr* PE = cast<ParenExpr>(E); 1899 return FindExpressionBaseAddressLValue(PE->getSubExpr()); 1900 } 1901 case Expr::MemberExprClass: { 1902 const MemberExpr *M = cast<MemberExpr>(E); 1903 if (M->isArrow()) 1904 return FindExpressionBaseAddress(M->getBase()); 1905 return FindExpressionBaseAddressLValue(M->getBase()); 1906 } 1907 case Expr::ArraySubscriptExprClass: { 1908 const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(E); 1909 return FindExpressionBaseAddress(ASE->getBase()); 1910 } 1911 case Expr::UnaryOperatorClass: { 1912 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1913 1914 if (Exp->getOpcode() == UnaryOperator::Deref) 1915 return FindExpressionBaseAddress(Exp->getSubExpr()); 1916 1917 return E; 1918 } 1919 } 1920} 1921 1922static const Expr* FindExpressionBaseAddress(const Expr* E) { 1923 switch (E->getStmtClass()) { 1924 default: 1925 return E; 1926 case Expr::ParenExprClass: { 1927 const ParenExpr* PE = cast<ParenExpr>(E); 1928 return FindExpressionBaseAddress(PE->getSubExpr()); 1929 } 1930 case Expr::UnaryOperatorClass: { 1931 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1932 1933 // C99 6.6p9 1934 if (Exp->getOpcode() == UnaryOperator::AddrOf) 1935 return FindExpressionBaseAddressLValue(Exp->getSubExpr()); 1936 1937 if (Exp->getOpcode() == UnaryOperator::Extension) 1938 return FindExpressionBaseAddress(Exp->getSubExpr()); 1939 1940 return E; 1941 } 1942 case Expr::BinaryOperatorClass: { 1943 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1944 1945 Expr *PExp = Exp->getLHS(); 1946 Expr *IExp = Exp->getRHS(); 1947 if (IExp->getType()->isPointerType()) 1948 std::swap(PExp, IExp); 1949 1950 return FindExpressionBaseAddress(PExp); 1951 } 1952 case Expr::ImplicitCastExprClass: { 1953 const Expr* SubExpr = cast<ImplicitCastExpr>(E)->getSubExpr(); 1954 1955 // Check for implicit promotion 1956 if (SubExpr->getType()->isFunctionType() || 1957 SubExpr->getType()->isArrayType()) 1958 return FindExpressionBaseAddressLValue(SubExpr); 1959 1960 // Check for pointer->pointer cast 1961 if (SubExpr->getType()->isPointerType()) 1962 return FindExpressionBaseAddress(SubExpr); 1963 1964 // We assume that we have an arithmetic expression here; 1965 // if we don't, we'll figure it out later 1966 return 0; 1967 } 1968 case Expr::CStyleCastExprClass: { 1969 const Expr* SubExpr = cast<CastExpr>(E)->getSubExpr(); 1970 1971 // Check for pointer->pointer cast 1972 if (SubExpr->getType()->isPointerType()) 1973 return FindExpressionBaseAddress(SubExpr); 1974 1975 // We assume that we have an arithmetic expression here; 1976 // if we don't, we'll figure it out later 1977 return 0; 1978 } 1979 } 1980} 1981 1982bool Sema::CheckArithmeticConstantExpression(const Expr* Init) { 1983 switch (Init->getStmtClass()) { 1984 default: 1985 InitializerElementNotConstant(Init); 1986 return true; 1987 case Expr::ParenExprClass: { 1988 const ParenExpr* PE = cast<ParenExpr>(Init); 1989 return CheckArithmeticConstantExpression(PE->getSubExpr()); 1990 } 1991 case Expr::FloatingLiteralClass: 1992 case Expr::IntegerLiteralClass: 1993 case Expr::CharacterLiteralClass: 1994 case Expr::ImaginaryLiteralClass: 1995 case Expr::TypesCompatibleExprClass: 1996 case Expr::CXXBoolLiteralExprClass: 1997 return false; 1998 case Expr::CallExprClass: 1999 case Expr::CXXOperatorCallExprClass: { 2000 const CallExpr *CE = cast<CallExpr>(Init); 2001 2002 // Allow any constant foldable calls to builtins. 2003 if (CE->isBuiltinCall() && CE->isEvaluatable(Context)) 2004 return false; 2005 2006 InitializerElementNotConstant(Init); 2007 return true; 2008 } 2009 case Expr::DeclRefExprClass: 2010 case Expr::QualifiedDeclRefExprClass: { 2011 const Decl *D = cast<DeclRefExpr>(Init)->getDecl(); 2012 if (isa<EnumConstantDecl>(D)) 2013 return false; 2014 InitializerElementNotConstant(Init); 2015 return true; 2016 } 2017 case Expr::CompoundLiteralExprClass: 2018 // Allow "(vector type){2,4}"; normal C constraints don't allow this, 2019 // but vectors are allowed to be magic. 2020 if (Init->getType()->isVectorType()) 2021 return false; 2022 InitializerElementNotConstant(Init); 2023 return true; 2024 case Expr::UnaryOperatorClass: { 2025 const UnaryOperator *Exp = cast<UnaryOperator>(Init); 2026 2027 switch (Exp->getOpcode()) { 2028 // Address, indirect, pre/post inc/dec, etc are not valid constant exprs. 2029 // See C99 6.6p3. 2030 default: 2031 InitializerElementNotConstant(Init); 2032 return true; 2033 case UnaryOperator::OffsetOf: 2034 if (Exp->getSubExpr()->getType()->isConstantSizeType()) 2035 return false; 2036 InitializerElementNotConstant(Init); 2037 return true; 2038 case UnaryOperator::Extension: 2039 case UnaryOperator::LNot: 2040 case UnaryOperator::Plus: 2041 case UnaryOperator::Minus: 2042 case UnaryOperator::Not: 2043 return CheckArithmeticConstantExpression(Exp->getSubExpr()); 2044 } 2045 } 2046 case Expr::SizeOfAlignOfExprClass: { 2047 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(Init); 2048 // Special check for void types, which are allowed as an extension 2049 if (Exp->getTypeOfArgument()->isVoidType()) 2050 return false; 2051 // alignof always evaluates to a constant. 2052 // FIXME: is sizeof(int[3.0]) a constant expression? 2053 if (Exp->isSizeOf() && !Exp->getTypeOfArgument()->isConstantSizeType()) { 2054 InitializerElementNotConstant(Init); 2055 return true; 2056 } 2057 return false; 2058 } 2059 case Expr::BinaryOperatorClass: { 2060 const BinaryOperator *Exp = cast<BinaryOperator>(Init); 2061 2062 if (Exp->getLHS()->getType()->isArithmeticType() && 2063 Exp->getRHS()->getType()->isArithmeticType()) { 2064 return CheckArithmeticConstantExpression(Exp->getLHS()) || 2065 CheckArithmeticConstantExpression(Exp->getRHS()); 2066 } 2067 2068 if (Exp->getLHS()->getType()->isPointerType() && 2069 Exp->getRHS()->getType()->isPointerType()) { 2070 const Expr* LHSBase = FindExpressionBaseAddress(Exp->getLHS()); 2071 const Expr* RHSBase = FindExpressionBaseAddress(Exp->getRHS()); 2072 2073 // Only allow a null (constant integer) base; we could 2074 // allow some additional cases if necessary, but this 2075 // is sufficient to cover offsetof-like constructs. 2076 if (!LHSBase && !RHSBase) { 2077 return CheckAddressConstantExpression(Exp->getLHS()) || 2078 CheckAddressConstantExpression(Exp->getRHS()); 2079 } 2080 } 2081 2082 InitializerElementNotConstant(Init); 2083 return true; 2084 } 2085 case Expr::ImplicitCastExprClass: 2086 case Expr::CStyleCastExprClass: { 2087 const CastExpr *CE = cast<CastExpr>(Init); 2088 const Expr *SubExpr = CE->getSubExpr(); 2089 2090 if (SubExpr->getType()->isArithmeticType()) 2091 return CheckArithmeticConstantExpression(SubExpr); 2092 2093 if (SubExpr->getType()->isPointerType()) { 2094 const Expr* Base = FindExpressionBaseAddress(SubExpr); 2095 if (Base) { 2096 // the cast is only valid if done to a wide enough type 2097 if (Context.getTypeSize(CE->getType()) >= 2098 Context.getTypeSize(SubExpr->getType())) 2099 return false; 2100 } else { 2101 // If the pointer has a null base, this is an offsetof-like construct 2102 return CheckAddressConstantExpression(SubExpr); 2103 } 2104 } 2105 2106 InitializerElementNotConstant(Init); 2107 return true; 2108 } 2109 case Expr::ConditionalOperatorClass: { 2110 const ConditionalOperator *Exp = cast<ConditionalOperator>(Init); 2111 2112 // If GNU extensions are disabled, we require all operands to be arithmetic 2113 // constant expressions. 2114 if (getLangOptions().NoExtensions) { 2115 return CheckArithmeticConstantExpression(Exp->getCond()) || 2116 (Exp->getLHS() && CheckArithmeticConstantExpression(Exp->getLHS())) || 2117 CheckArithmeticConstantExpression(Exp->getRHS()); 2118 } 2119 2120 // Otherwise, we have to emulate some of the behavior of fold here. 2121 // Basically GCC treats things like "4 ? 1 : somefunc()" as a constant 2122 // because it can constant fold things away. To retain compatibility with 2123 // GCC code, we see if we can fold the condition to a constant (which we 2124 // should always be able to do in theory). If so, we only require the 2125 // specified arm of the conditional to be a constant. This is a horrible 2126 // hack, but is require by real world code that uses __builtin_constant_p. 2127 Expr::EvalResult EvalResult; 2128 if (!Exp->getCond()->Evaluate(EvalResult, Context) || 2129 EvalResult.HasSideEffects) { 2130 // If Evaluate couldn't fold it, CheckArithmeticConstantExpression 2131 // won't be able to either. Use it to emit the diagnostic though. 2132 bool Res = CheckArithmeticConstantExpression(Exp->getCond()); 2133 assert(Res && "Evaluate couldn't evaluate this constant?"); 2134 return Res; 2135 } 2136 2137 // Verify that the side following the condition is also a constant. 2138 const Expr *TrueSide = Exp->getLHS(), *FalseSide = Exp->getRHS(); 2139 if (EvalResult.Val.getInt() == 0) 2140 std::swap(TrueSide, FalseSide); 2141 2142 if (TrueSide && CheckArithmeticConstantExpression(TrueSide)) 2143 return true; 2144 2145 // Okay, the evaluated side evaluates to a constant, so we accept this. 2146 // Check to see if the other side is obviously not a constant. If so, 2147 // emit a warning that this is a GNU extension. 2148 if (FalseSide && !FalseSide->isEvaluatable(Context)) 2149 Diag(Init->getExprLoc(), 2150 diag::ext_typecheck_expression_not_constant_but_accepted) 2151 << FalseSide->getSourceRange(); 2152 return false; 2153 } 2154 } 2155} 2156 2157bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2158 if (DesignatedInitExpr *DIE = dyn_cast<DesignatedInitExpr>(Init)) 2159 Init = DIE->getInit(); 2160 2161 Init = Init->IgnoreParens(); 2162 2163 if (Init->isEvaluatable(Context)) 2164 return false; 2165 2166 // Look through CXXDefaultArgExprs; they have no meaning in this context. 2167 if (CXXDefaultArgExpr* DAE = dyn_cast<CXXDefaultArgExpr>(Init)) 2168 return CheckForConstantInitializer(DAE->getExpr(), DclT); 2169 2170 if (CompoundLiteralExpr *e = dyn_cast<CompoundLiteralExpr>(Init)) 2171 return CheckForConstantInitializer(e->getInitializer(), DclT); 2172 2173 if (isa<ImplicitValueInitExpr>(Init)) { 2174 // FIXME: In C++, check for non-POD types. 2175 return false; 2176 } 2177 2178 if (InitListExpr *Exp = dyn_cast<InitListExpr>(Init)) { 2179 unsigned numInits = Exp->getNumInits(); 2180 for (unsigned i = 0; i < numInits; i++) { 2181 // FIXME: Need to get the type of the declaration for C++, 2182 // because it could be a reference? 2183 2184 if (CheckForConstantInitializer(Exp->getInit(i), 2185 Exp->getInit(i)->getType())) 2186 return true; 2187 } 2188 return false; 2189 } 2190 2191 // FIXME: We can probably remove some of this code below, now that 2192 // Expr::Evaluate is doing the heavy lifting for scalars. 2193 2194 if (Init->isNullPointerConstant(Context)) 2195 return false; 2196 if (Init->getType()->isArithmeticType()) { 2197 QualType InitTy = Context.getCanonicalType(Init->getType()) 2198 .getUnqualifiedType(); 2199 if (InitTy == Context.BoolTy) { 2200 // Special handling for pointers implicitly cast to bool; 2201 // (e.g. "_Bool rr = &rr;"). This is only legal at the top level. 2202 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Init)) { 2203 Expr* SubE = ICE->getSubExpr(); 2204 if (SubE->getType()->isPointerType() || 2205 SubE->getType()->isArrayType() || 2206 SubE->getType()->isFunctionType()) { 2207 return CheckAddressConstantExpression(Init); 2208 } 2209 } 2210 } else if (InitTy->isIntegralType()) { 2211 Expr* SubE = 0; 2212 if (CastExpr* CE = dyn_cast<CastExpr>(Init)) 2213 SubE = CE->getSubExpr(); 2214 // Special check for pointer cast to int; we allow as an extension 2215 // an address constant cast to an integer if the integer 2216 // is of an appropriate width (this sort of code is apparently used 2217 // in some places). 2218 // FIXME: Add pedwarn? 2219 // FIXME: Don't allow bitfields here! Need the FieldDecl for that. 2220 if (SubE && (SubE->getType()->isPointerType() || 2221 SubE->getType()->isArrayType() || 2222 SubE->getType()->isFunctionType())) { 2223 unsigned IntWidth = Context.getTypeSize(Init->getType()); 2224 unsigned PointerWidth = Context.getTypeSize(Context.VoidPtrTy); 2225 if (IntWidth >= PointerWidth) 2226 return CheckAddressConstantExpression(Init); 2227 } 2228 } 2229 2230 return CheckArithmeticConstantExpression(Init); 2231 } 2232 2233 if (Init->getType()->isPointerType()) 2234 return CheckAddressConstantExpression(Init); 2235 2236 // An array type at the top level that isn't an init-list must 2237 // be a string literal 2238 if (Init->getType()->isArrayType()) 2239 return false; 2240 2241 if (Init->getType()->isFunctionType()) 2242 return false; 2243 2244 // Allow block exprs at top level. 2245 if (Init->getType()->isBlockPointerType()) 2246 return false; 2247 2248 // GCC cast to union extension 2249 // note: the validity of the cast expr is checked by CheckCastTypes() 2250 if (CastExpr *C = dyn_cast<CastExpr>(Init)) { 2251 QualType T = C->getType(); 2252 return T->isUnionType() && CheckForConstantInitializer(C->getSubExpr(), T); 2253 } 2254 2255 InitializerElementNotConstant(Init); 2256 return true; 2257} 2258 2259void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init) { 2260 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2261} 2262 2263/// AddInitializerToDecl - Adds the initializer Init to the 2264/// declaration dcl. If DirectInit is true, this is C++ direct 2265/// initialization rather than copy initialization. 2266void Sema::AddInitializerToDecl(DeclTy *dcl, ExprArg init, bool DirectInit) { 2267 Decl *RealDecl = static_cast<Decl *>(dcl); 2268 Expr *Init = static_cast<Expr *>(init.release()); 2269 assert(Init && "missing initializer"); 2270 2271 // If there is no declaration, there was an error parsing it. Just ignore 2272 // the initializer. 2273 if (RealDecl == 0) { 2274 Init->Destroy(Context); 2275 return; 2276 } 2277 2278 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2279 if (!VDecl) { 2280 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2281 RealDecl->setInvalidDecl(); 2282 return; 2283 } 2284 // Get the decls type and save a reference for later, since 2285 // CheckInitializerTypes may change it. 2286 QualType DclT = VDecl->getType(), SavT = DclT; 2287 if (VDecl->isBlockVarDecl()) { 2288 VarDecl::StorageClass SC = VDecl->getStorageClass(); 2289 if (SC == VarDecl::Extern) { // C99 6.7.8p5 2290 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2291 VDecl->setInvalidDecl(); 2292 } else if (!VDecl->isInvalidDecl()) { 2293 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2294 VDecl->getDeclName(), DirectInit)) 2295 VDecl->setInvalidDecl(); 2296 2297 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2298 if (!getLangOptions().CPlusPlus) { 2299 if (SC == VarDecl::Static) // C99 6.7.8p4. 2300 CheckForConstantInitializer(Init, DclT); 2301 } 2302 } 2303 } else if (VDecl->isFileVarDecl()) { 2304 if (VDecl->getStorageClass() == VarDecl::Extern) 2305 Diag(VDecl->getLocation(), diag::warn_extern_init); 2306 if (!VDecl->isInvalidDecl()) 2307 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2308 VDecl->getDeclName(), DirectInit)) 2309 VDecl->setInvalidDecl(); 2310 2311 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2312 if (!getLangOptions().CPlusPlus) { 2313 // C99 6.7.8p4. All file scoped initializers need to be constant. 2314 CheckForConstantInitializer(Init, DclT); 2315 } 2316 } 2317 // If the type changed, it means we had an incomplete type that was 2318 // completed by the initializer. For example: 2319 // int ary[] = { 1, 3, 5 }; 2320 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2321 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2322 VDecl->setType(DclT); 2323 Init->setType(DclT); 2324 } 2325 2326 // Attach the initializer to the decl. 2327 VDecl->setInit(Init); 2328 return; 2329} 2330 2331void Sema::ActOnUninitializedDecl(DeclTy *dcl) { 2332 Decl *RealDecl = static_cast<Decl *>(dcl); 2333 2334 // If there is no declaration, there was an error parsing it. Just ignore it. 2335 if (RealDecl == 0) 2336 return; 2337 2338 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2339 QualType Type = Var->getType(); 2340 // C++ [dcl.init.ref]p3: 2341 // The initializer can be omitted for a reference only in a 2342 // parameter declaration (8.3.5), in the declaration of a 2343 // function return type, in the declaration of a class member 2344 // within its class declaration (9.2), and where the extern 2345 // specifier is explicitly used. 2346 if (Type->isReferenceType() && 2347 Var->getStorageClass() != VarDecl::Extern && 2348 Var->getStorageClass() != VarDecl::PrivateExtern) { 2349 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2350 << Var->getDeclName() 2351 << SourceRange(Var->getLocation(), Var->getLocation()); 2352 Var->setInvalidDecl(); 2353 return; 2354 } 2355 2356 // C++ [dcl.init]p9: 2357 // 2358 // If no initializer is specified for an object, and the object 2359 // is of (possibly cv-qualified) non-POD class type (or array 2360 // thereof), the object shall be default-initialized; if the 2361 // object is of const-qualified type, the underlying class type 2362 // shall have a user-declared default constructor. 2363 if (getLangOptions().CPlusPlus) { 2364 QualType InitType = Type; 2365 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2366 InitType = Array->getElementType(); 2367 if (Var->getStorageClass() != VarDecl::Extern && 2368 Var->getStorageClass() != VarDecl::PrivateExtern && 2369 InitType->isRecordType()) { 2370 const CXXConstructorDecl *Constructor 2371 = PerformInitializationByConstructor(InitType, 0, 0, 2372 Var->getLocation(), 2373 SourceRange(Var->getLocation(), 2374 Var->getLocation()), 2375 Var->getDeclName(), 2376 IK_Default); 2377 if (!Constructor) 2378 Var->setInvalidDecl(); 2379 } 2380 } 2381 2382#if 0 2383 // FIXME: Temporarily disabled because we are not properly parsing 2384 // linkage specifications on declarations, e.g., 2385 // 2386 // extern "C" const CGPoint CGPointerZero; 2387 // 2388 // C++ [dcl.init]p9: 2389 // 2390 // If no initializer is specified for an object, and the 2391 // object is of (possibly cv-qualified) non-POD class type (or 2392 // array thereof), the object shall be default-initialized; if 2393 // the object is of const-qualified type, the underlying class 2394 // type shall have a user-declared default 2395 // constructor. Otherwise, if no initializer is specified for 2396 // an object, the object and its subobjects, if any, have an 2397 // indeterminate initial value; if the object or any of its 2398 // subobjects are of const-qualified type, the program is 2399 // ill-formed. 2400 // 2401 // This isn't technically an error in C, so we don't diagnose it. 2402 // 2403 // FIXME: Actually perform the POD/user-defined default 2404 // constructor check. 2405 if (getLangOptions().CPlusPlus && 2406 Context.getCanonicalType(Type).isConstQualified() && 2407 Var->getStorageClass() != VarDecl::Extern) 2408 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2409 << Var->getName() 2410 << SourceRange(Var->getLocation(), Var->getLocation()); 2411#endif 2412 } 2413} 2414 2415/// The declarators are chained together backwards, reverse the list. 2416Sema::DeclTy *Sema::FinalizeDeclaratorGroup(Scope *S, DeclTy *group) { 2417 // Often we have single declarators, handle them quickly. 2418 Decl *GroupDecl = static_cast<Decl*>(group); 2419 if (GroupDecl == 0) 2420 return 0; 2421 2422 Decl *Group = dyn_cast<Decl>(GroupDecl); 2423 Decl *NewGroup = 0; 2424 if (Group->getNextDeclarator() == 0) 2425 NewGroup = Group; 2426 else { // reverse the list. 2427 while (Group) { 2428 Decl *Next = Group->getNextDeclarator(); 2429 Group->setNextDeclarator(NewGroup); 2430 NewGroup = Group; 2431 Group = Next; 2432 } 2433 } 2434 // Perform semantic analysis that depends on having fully processed both 2435 // the declarator and initializer. 2436 for (Decl *ID = NewGroup; ID; ID = ID->getNextDeclarator()) { 2437 VarDecl *IDecl = dyn_cast<VarDecl>(ID); 2438 if (!IDecl) 2439 continue; 2440 QualType T = IDecl->getType(); 2441 2442 if (T->isVariableArrayType()) { 2443 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2444 2445 // FIXME: This won't give the correct result for 2446 // int a[10][n]; 2447 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2448 if (IDecl->isFileVarDecl()) { 2449 Diag(IDecl->getLocation(), diag::err_vla_decl_in_file_scope) << 2450 SizeRange; 2451 2452 IDecl->setInvalidDecl(); 2453 } else { 2454 // C99 6.7.5.2p2: If an identifier is declared to be an object with 2455 // static storage duration, it shall not have a variable length array. 2456 if (IDecl->getStorageClass() == VarDecl::Static) { 2457 Diag(IDecl->getLocation(), diag::err_vla_decl_has_static_storage) 2458 << SizeRange; 2459 IDecl->setInvalidDecl(); 2460 } else if (IDecl->getStorageClass() == VarDecl::Extern) { 2461 Diag(IDecl->getLocation(), diag::err_vla_decl_has_extern_linkage) 2462 << SizeRange; 2463 IDecl->setInvalidDecl(); 2464 } 2465 } 2466 } else if (T->isVariablyModifiedType()) { 2467 if (IDecl->isFileVarDecl()) { 2468 Diag(IDecl->getLocation(), diag::err_vm_decl_in_file_scope); 2469 IDecl->setInvalidDecl(); 2470 } else { 2471 if (IDecl->getStorageClass() == VarDecl::Extern) { 2472 Diag(IDecl->getLocation(), diag::err_vm_decl_has_extern_linkage); 2473 IDecl->setInvalidDecl(); 2474 } 2475 } 2476 } 2477 2478 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2479 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2480 if (IDecl->isBlockVarDecl() && 2481 IDecl->getStorageClass() != VarDecl::Extern) { 2482 if (!IDecl->isInvalidDecl() && 2483 DiagnoseIncompleteType(IDecl->getLocation(), T, 2484 diag::err_typecheck_decl_incomplete_type)) 2485 IDecl->setInvalidDecl(); 2486 } 2487 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2488 // object that has file scope without an initializer, and without a 2489 // storage-class specifier or with the storage-class specifier "static", 2490 // constitutes a tentative definition. Note: A tentative definition with 2491 // external linkage is valid (C99 6.2.2p5). 2492 if (isTentativeDefinition(IDecl)) { 2493 if (T->isIncompleteArrayType()) { 2494 // C99 6.9.2 (p2, p5): Implicit initialization causes an incomplete 2495 // array to be completed. Don't issue a diagnostic. 2496 } else if (!IDecl->isInvalidDecl() && 2497 DiagnoseIncompleteType(IDecl->getLocation(), T, 2498 diag::err_typecheck_decl_incomplete_type)) 2499 // C99 6.9.2p3: If the declaration of an identifier for an object is 2500 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2501 // declared type shall not be an incomplete type. 2502 IDecl->setInvalidDecl(); 2503 } 2504 if (IDecl->isFileVarDecl()) 2505 CheckForFileScopedRedefinitions(S, IDecl); 2506 } 2507 return NewGroup; 2508} 2509 2510/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2511/// to introduce parameters into function prototype scope. 2512Sema::DeclTy * 2513Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2514 const DeclSpec &DS = D.getDeclSpec(); 2515 2516 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2517 VarDecl::StorageClass StorageClass = VarDecl::None; 2518 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2519 StorageClass = VarDecl::Register; 2520 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2521 Diag(DS.getStorageClassSpecLoc(), 2522 diag::err_invalid_storage_class_in_func_decl); 2523 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2524 } 2525 if (DS.isThreadSpecified()) { 2526 Diag(DS.getThreadSpecLoc(), 2527 diag::err_invalid_storage_class_in_func_decl); 2528 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2529 } 2530 2531 // Check that there are no default arguments inside the type of this 2532 // parameter (C++ only). 2533 if (getLangOptions().CPlusPlus) 2534 CheckExtraCXXDefaultArguments(D); 2535 2536 // In this context, we *do not* check D.getInvalidType(). If the declarator 2537 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2538 // though it will not reflect the user specified type. 2539 QualType parmDeclType = GetTypeForDeclarator(D, S); 2540 2541 assert(!parmDeclType.isNull() && "GetTypeForDeclarator() returned null type"); 2542 2543 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2544 // Can this happen for params? We already checked that they don't conflict 2545 // among each other. Here they can only shadow globals, which is ok. 2546 IdentifierInfo *II = D.getIdentifier(); 2547 if (II) { 2548 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2549 if (PrevDecl->isTemplateParameter()) { 2550 // Maybe we will complain about the shadowed template parameter. 2551 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2552 // Just pretend that we didn't see the previous declaration. 2553 PrevDecl = 0; 2554 } else if (S->isDeclScope(PrevDecl)) { 2555 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2556 2557 // Recover by removing the name 2558 II = 0; 2559 D.SetIdentifier(0, D.getIdentifierLoc()); 2560 } 2561 } 2562 } 2563 2564 // Perform the default function/array conversion (C99 6.7.5.3p[7,8]). 2565 // Doing the promotion here has a win and a loss. The win is the type for 2566 // both Decl's and DeclRefExpr's will match (a convenient invariant for the 2567 // code generator). The loss is the orginal type isn't preserved. For example: 2568 // 2569 // void func(int parmvardecl[5]) { // convert "int [5]" to "int *" 2570 // int blockvardecl[5]; 2571 // sizeof(parmvardecl); // size == 4 2572 // sizeof(blockvardecl); // size == 20 2573 // } 2574 // 2575 // For expressions, all implicit conversions are captured using the 2576 // ImplicitCastExpr AST node (we have no such mechanism for Decl's). 2577 // 2578 // FIXME: If a source translation tool needs to see the original type, then 2579 // we need to consider storing both types (in ParmVarDecl)... 2580 // 2581 if (parmDeclType->isArrayType()) { 2582 // int x[restrict 4] -> int *restrict 2583 parmDeclType = Context.getArrayDecayedType(parmDeclType); 2584 } else if (parmDeclType->isFunctionType()) 2585 parmDeclType = Context.getPointerType(parmDeclType); 2586 2587 ParmVarDecl *New = ParmVarDecl::Create(Context, CurContext, 2588 D.getIdentifierLoc(), II, 2589 parmDeclType, StorageClass, 2590 0); 2591 2592 if (D.getInvalidType()) 2593 New->setInvalidDecl(); 2594 2595 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2596 if (D.getCXXScopeSpec().isSet()) { 2597 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2598 << D.getCXXScopeSpec().getRange(); 2599 New->setInvalidDecl(); 2600 } 2601 2602 // Add the parameter declaration into this scope. 2603 S->AddDecl(New); 2604 if (II) 2605 IdResolver.AddDecl(New); 2606 2607 ProcessDeclAttributes(New, D); 2608 return New; 2609 2610} 2611 2612void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D) { 2613 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2614 "Not a function declarator!"); 2615 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2616 2617 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2618 // for a K&R function. 2619 if (!FTI.hasPrototype) { 2620 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2621 if (FTI.ArgInfo[i].Param == 0) { 2622 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2623 << FTI.ArgInfo[i].Ident; 2624 // Implicitly declare the argument as type 'int' for lack of a better 2625 // type. 2626 DeclSpec DS; 2627 const char* PrevSpec; // unused 2628 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2629 PrevSpec); 2630 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2631 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2632 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2633 } 2634 } 2635 } 2636} 2637 2638Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Declarator &D) { 2639 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2640 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2641 "Not a function declarator!"); 2642 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2643 2644 if (FTI.hasPrototype) { 2645 // FIXME: Diagnose arguments without names in C. 2646 } 2647 2648 Scope *ParentScope = FnBodyScope->getParent(); 2649 2650 return ActOnStartOfFunctionDef(FnBodyScope, 2651 ActOnDeclarator(ParentScope, D, 0, 2652 /*IsFunctionDefinition=*/true)); 2653} 2654 2655Sema::DeclTy *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclTy *D) { 2656 Decl *decl = static_cast<Decl*>(D); 2657 FunctionDecl *FD = cast<FunctionDecl>(decl); 2658 2659 // See if this is a redefinition. 2660 const FunctionDecl *Definition; 2661 if (FD->getBody(Definition)) { 2662 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2663 Diag(Definition->getLocation(), diag::note_previous_definition); 2664 } 2665 2666 PushDeclContext(FnBodyScope, FD); 2667 2668 // Check the validity of our function parameters 2669 CheckParmsForFunctionDef(FD); 2670 2671 // Introduce our parameters into the function scope 2672 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2673 ParmVarDecl *Param = FD->getParamDecl(p); 2674 Param->setOwningFunction(FD); 2675 2676 // If this has an identifier, add it to the scope stack. 2677 if (Param->getIdentifier()) 2678 PushOnScopeChains(Param, FnBodyScope); 2679 } 2680 2681 // Checking attributes of current function definition 2682 // dllimport attribute. 2683 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2684 // dllimport attribute cannot be applied to definition. 2685 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2686 Diag(FD->getLocation(), 2687 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2688 << "dllimport"; 2689 FD->setInvalidDecl(); 2690 return FD; 2691 } else { 2692 // If a symbol previously declared dllimport is later defined, the 2693 // attribute is ignored in subsequent references, and a warning is 2694 // emitted. 2695 Diag(FD->getLocation(), 2696 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2697 << FD->getNameAsCString() << "dllimport"; 2698 } 2699 } 2700 return FD; 2701} 2702 2703Sema::DeclTy *Sema::ActOnFinishFunctionBody(DeclTy *D, StmtArg BodyArg) { 2704 Decl *dcl = static_cast<Decl *>(D); 2705 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2706 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2707 FD->setBody(Body); 2708 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2709 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2710 MD->setBody((Stmt*)Body); 2711 } else { 2712 Body->Destroy(Context); 2713 return 0; 2714 } 2715 PopDeclContext(); 2716 // Verify and clean out per-function state. 2717 2718 // Check goto/label use. 2719 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 2720 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 2721 // Verify that we have no forward references left. If so, there was a goto 2722 // or address of a label taken, but no definition of it. Label fwd 2723 // definitions are indicated with a null substmt. 2724 if (I->second->getSubStmt() == 0) { 2725 LabelStmt *L = I->second; 2726 // Emit error. 2727 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 2728 2729 // At this point, we have gotos that use the bogus label. Stitch it into 2730 // the function body so that they aren't leaked and that the AST is well 2731 // formed. 2732 if (Body) { 2733#if 0 2734 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 2735 // and the AST is malformed anyway. We should just blow away 'L'. 2736 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 2737 cast<CompoundStmt>(Body)->push_back(L); 2738#else 2739 L->Destroy(Context); 2740#endif 2741 } else { 2742 // The whole function wasn't parsed correctly, just delete this. 2743 L->Destroy(Context); 2744 } 2745 } 2746 } 2747 LabelMap.clear(); 2748 2749 return D; 2750} 2751 2752/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 2753/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 2754NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 2755 IdentifierInfo &II, Scope *S) { 2756 // Extension in C99. Legal in C90, but warn about it. 2757 if (getLangOptions().C99) 2758 Diag(Loc, diag::ext_implicit_function_decl) << &II; 2759 else 2760 Diag(Loc, diag::warn_implicit_function_decl) << &II; 2761 2762 // FIXME: handle stuff like: 2763 // void foo() { extern float X(); } 2764 // void bar() { X(); } <-- implicit decl for X in another scope. 2765 2766 // Set a Declarator for the implicit definition: int foo(); 2767 const char *Dummy; 2768 DeclSpec DS; 2769 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 2770 Error = Error; // Silence warning. 2771 assert(!Error && "Error setting up implicit decl!"); 2772 Declarator D(DS, Declarator::BlockContext); 2773 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, 0, 0, 0, Loc, D), 2774 SourceLocation()); 2775 D.SetIdentifier(&II, Loc); 2776 2777 // Insert this function into translation-unit scope. 2778 2779 DeclContext *PrevDC = CurContext; 2780 CurContext = Context.getTranslationUnitDecl(); 2781 2782 FunctionDecl *FD = 2783 dyn_cast<FunctionDecl>(static_cast<Decl*>(ActOnDeclarator(TUScope, D, 0))); 2784 FD->setImplicit(); 2785 2786 CurContext = PrevDC; 2787 2788 return FD; 2789} 2790 2791 2792TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 2793 Decl *LastDeclarator) { 2794 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 2795 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 2796 2797 // Scope manipulation handled by caller. 2798 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 2799 D.getIdentifierLoc(), 2800 D.getIdentifier(), 2801 T); 2802 NewTD->setNextDeclarator(LastDeclarator); 2803 if (D.getInvalidType()) 2804 NewTD->setInvalidDecl(); 2805 return NewTD; 2806} 2807 2808/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 2809/// former case, Name will be non-null. In the later case, Name will be null. 2810/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 2811/// reference/declaration/definition of a tag. 2812Sema::DeclTy *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 2813 SourceLocation KWLoc, const CXXScopeSpec &SS, 2814 IdentifierInfo *Name, SourceLocation NameLoc, 2815 AttributeList *Attr) { 2816 // If this is not a definition, it must have a name. 2817 assert((Name != 0 || TK == TK_Definition) && 2818 "Nameless record must be a definition!"); 2819 2820 TagDecl::TagKind Kind; 2821 switch (TagSpec) { 2822 default: assert(0 && "Unknown tag type!"); 2823 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 2824 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 2825 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 2826 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 2827 } 2828 2829 DeclContext *SearchDC = CurContext; 2830 DeclContext *DC = CurContext; 2831 NamedDecl *PrevDecl = 0; 2832 2833 bool Invalid = false; 2834 2835 if (Name && SS.isNotEmpty()) { 2836 // We have a nested-name tag ('struct foo::bar'). 2837 2838 // Check for invalid 'foo::'. 2839 if (SS.isInvalid()) { 2840 Name = 0; 2841 goto CreateNewDecl; 2842 } 2843 2844 DC = static_cast<DeclContext*>(SS.getScopeRep()); 2845 SearchDC = DC; 2846 // Look-up name inside 'foo::'. 2847 PrevDecl = dyn_cast_or_null<TagDecl>( 2848 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 2849 2850 // A tag 'foo::bar' must already exist. 2851 if (PrevDecl == 0) { 2852 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 2853 Name = 0; 2854 goto CreateNewDecl; 2855 } 2856 } else if (Name) { 2857 // If this is a named struct, check to see if there was a previous forward 2858 // declaration or definition. 2859 // FIXME: We're looking into outer scopes here, even when we 2860 // shouldn't be. Doing so can result in ambiguities that we 2861 // shouldn't be diagnosing. 2862 LookupResult R = LookupName(S, Name, LookupTagName, 2863 /*RedeclarationOnly=*/(TK != TK_Reference)); 2864 if (R.isAmbiguous()) { 2865 DiagnoseAmbiguousLookup(R, Name, NameLoc); 2866 // FIXME: This is not best way to recover from case like: 2867 // 2868 // struct S s; 2869 // 2870 // causes needless err_ovl_no_viable_function_in_init latter. 2871 Name = 0; 2872 PrevDecl = 0; 2873 Invalid = true; 2874 } 2875 else 2876 PrevDecl = R; 2877 2878 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 2879 // FIXME: This makes sure that we ignore the contexts associated 2880 // with C structs, unions, and enums when looking for a matching 2881 // tag declaration or definition. See the similar lookup tweak 2882 // in Sema::LookupName; is there a better way to deal with this? 2883 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 2884 SearchDC = SearchDC->getParent(); 2885 } 2886 } 2887 2888 if (PrevDecl && PrevDecl->isTemplateParameter()) { 2889 // Maybe we will complain about the shadowed template parameter. 2890 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 2891 // Just pretend that we didn't see the previous declaration. 2892 PrevDecl = 0; 2893 } 2894 2895 if (PrevDecl) { 2896 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 2897 // If this is a use of a previous tag, or if the tag is already declared 2898 // in the same scope (so that the definition/declaration completes or 2899 // rementions the tag), reuse the decl. 2900 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 2901 // Make sure that this wasn't declared as an enum and now used as a 2902 // struct or something similar. 2903 if (PrevTagDecl->getTagKind() != Kind) { 2904 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 2905 Diag(PrevDecl->getLocation(), diag::note_previous_use); 2906 // Recover by making this an anonymous redefinition. 2907 Name = 0; 2908 PrevDecl = 0; 2909 Invalid = true; 2910 } else { 2911 // If this is a use, just return the declaration we found. 2912 2913 // FIXME: In the future, return a variant or some other clue 2914 // for the consumer of this Decl to know it doesn't own it. 2915 // For our current ASTs this shouldn't be a problem, but will 2916 // need to be changed with DeclGroups. 2917 if (TK == TK_Reference) 2918 return PrevDecl; 2919 2920 // Diagnose attempts to redefine a tag. 2921 if (TK == TK_Definition) { 2922 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 2923 Diag(NameLoc, diag::err_redefinition) << Name; 2924 Diag(Def->getLocation(), diag::note_previous_definition); 2925 // If this is a redefinition, recover by making this 2926 // struct be anonymous, which will make any later 2927 // references get the previous definition. 2928 Name = 0; 2929 PrevDecl = 0; 2930 Invalid = true; 2931 } else { 2932 // If the type is currently being defined, complain 2933 // about a nested redefinition. 2934 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 2935 if (Tag->isBeingDefined()) { 2936 Diag(NameLoc, diag::err_nested_redefinition) << Name; 2937 Diag(PrevTagDecl->getLocation(), 2938 diag::note_previous_definition); 2939 Name = 0; 2940 PrevDecl = 0; 2941 Invalid = true; 2942 } 2943 } 2944 2945 // Okay, this is definition of a previously declared or referenced 2946 // tag PrevDecl. We're going to create a new Decl for it. 2947 } 2948 } 2949 // If we get here we have (another) forward declaration or we 2950 // have a definition. Just create a new decl. 2951 } else { 2952 // If we get here, this is a definition of a new tag type in a nested 2953 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 2954 // new decl/type. We set PrevDecl to NULL so that the entities 2955 // have distinct types. 2956 PrevDecl = 0; 2957 } 2958 // If we get here, we're going to create a new Decl. If PrevDecl 2959 // is non-NULL, it's a definition of the tag declared by 2960 // PrevDecl. If it's NULL, we have a new definition. 2961 } else { 2962 // PrevDecl is a namespace, template, or anything else 2963 // that lives in the IDNS_Tag identifier namespace. 2964 if (isDeclInScope(PrevDecl, SearchDC, S)) { 2965 // The tag name clashes with a namespace name, issue an error and 2966 // recover by making this tag be anonymous. 2967 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 2968 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 2969 Name = 0; 2970 PrevDecl = 0; 2971 Invalid = true; 2972 } else { 2973 // The existing declaration isn't relevant to us; we're in a 2974 // new scope, so clear out the previous declaration. 2975 PrevDecl = 0; 2976 } 2977 } 2978 } else if (TK == TK_Reference && SS.isEmpty() && Name && 2979 (Kind != TagDecl::TK_enum)) { 2980 // C++ [basic.scope.pdecl]p5: 2981 // -- for an elaborated-type-specifier of the form 2982 // 2983 // class-key identifier 2984 // 2985 // if the elaborated-type-specifier is used in the 2986 // decl-specifier-seq or parameter-declaration-clause of a 2987 // function defined in namespace scope, the identifier is 2988 // declared as a class-name in the namespace that contains 2989 // the declaration; otherwise, except as a friend 2990 // declaration, the identifier is declared in the smallest 2991 // non-class, non-function-prototype scope that contains the 2992 // declaration. 2993 // 2994 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 2995 // C structs and unions. 2996 2997 // Find the context where we'll be declaring the tag. 2998 // FIXME: We would like to maintain the current DeclContext as the 2999 // lexical context, 3000 while (SearchDC->isRecord()) 3001 SearchDC = SearchDC->getParent(); 3002 3003 // Find the scope where we'll be declaring the tag. 3004 while (S->isClassScope() || 3005 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3006 ((S->getFlags() & Scope::DeclScope) == 0) || 3007 (S->getEntity() && 3008 ((DeclContext *)S->getEntity())->isTransparentContext())) 3009 S = S->getParent(); 3010 } 3011 3012CreateNewDecl: 3013 3014 // If there is an identifier, use the location of the identifier as the 3015 // location of the decl, otherwise use the location of the struct/union 3016 // keyword. 3017 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3018 3019 // Otherwise, create a new declaration. If there is a previous 3020 // declaration of the same entity, the two will be linked via 3021 // PrevDecl. 3022 TagDecl *New; 3023 3024 if (Kind == TagDecl::TK_enum) { 3025 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3026 // enum X { A, B, C } D; D should chain to X. 3027 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3028 cast_or_null<EnumDecl>(PrevDecl)); 3029 // If this is an undefined enum, warn. 3030 if (TK != TK_Definition) Diag(Loc, diag::ext_forward_ref_enum); 3031 } else { 3032 // struct/union/class 3033 3034 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3035 // struct X { int A; } D; D should chain to X. 3036 if (getLangOptions().CPlusPlus) 3037 // FIXME: Look for a way to use RecordDecl for simple structs. 3038 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3039 cast_or_null<CXXRecordDecl>(PrevDecl)); 3040 else 3041 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3042 cast_or_null<RecordDecl>(PrevDecl)); 3043 } 3044 3045 if (Kind != TagDecl::TK_enum) { 3046 // Handle #pragma pack: if the #pragma pack stack has non-default 3047 // alignment, make up a packed attribute for this decl. These 3048 // attributes are checked when the ASTContext lays out the 3049 // structure. 3050 // 3051 // It is important for implementing the correct semantics that this 3052 // happen here (in act on tag decl). The #pragma pack stack is 3053 // maintained as a result of parser callbacks which can occur at 3054 // many points during the parsing of a struct declaration (because 3055 // the #pragma tokens are effectively skipped over during the 3056 // parsing of the struct). 3057 if (unsigned Alignment = PackContext.getAlignment()) 3058 New->addAttr(new PackedAttr(Alignment * 8)); 3059 } 3060 3061 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3062 // C++ [dcl.typedef]p3: 3063 // [...] Similarly, in a given scope, a class or enumeration 3064 // shall not be declared with the same name as a typedef-name 3065 // that is declared in that scope and refers to a type other 3066 // than the class or enumeration itself. 3067 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3068 TypedefDecl *PrevTypedef = 0; 3069 if (Lookup.getKind() == LookupResult::Found) 3070 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3071 3072 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3073 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3074 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3075 Diag(Loc, diag::err_tag_definition_of_typedef) 3076 << Context.getTypeDeclType(New) 3077 << PrevTypedef->getUnderlyingType(); 3078 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3079 Invalid = true; 3080 } 3081 } 3082 3083 if (Invalid) 3084 New->setInvalidDecl(); 3085 3086 if (Attr) 3087 ProcessDeclAttributeList(New, Attr); 3088 3089 // If we're declaring or defining a tag in function prototype scope 3090 // in C, note that this type can only be used within the function. 3091 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3092 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3093 3094 // Set the lexical context. If the tag has a C++ scope specifier, the 3095 // lexical context will be different from the semantic context. 3096 New->setLexicalDeclContext(CurContext); 3097 3098 if (TK == TK_Definition) 3099 New->startDefinition(); 3100 3101 // If this has an identifier, add it to the scope stack. 3102 if (Name) { 3103 S = getNonFieldDeclScope(S); 3104 PushOnScopeChains(New, S); 3105 } else { 3106 CurContext->addDecl(New); 3107 } 3108 3109 return New; 3110} 3111 3112void Sema::ActOnTagStartDefinition(Scope *S, DeclTy *TagD) { 3113 AdjustDeclIfTemplate(TagD); 3114 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3115 3116 // Enter the tag context. 3117 PushDeclContext(S, Tag); 3118 3119 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3120 FieldCollector->StartClass(); 3121 3122 if (Record->getIdentifier()) { 3123 // C++ [class]p2: 3124 // [...] The class-name is also inserted into the scope of the 3125 // class itself; this is known as the injected-class-name. For 3126 // purposes of access checking, the injected-class-name is treated 3127 // as if it were a public member name. 3128 RecordDecl *InjectedClassName 3129 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3130 CurContext, Record->getLocation(), 3131 Record->getIdentifier(), Record); 3132 InjectedClassName->setImplicit(); 3133 PushOnScopeChains(InjectedClassName, S); 3134 } 3135 } 3136} 3137 3138void Sema::ActOnTagFinishDefinition(Scope *S, DeclTy *TagD) { 3139 AdjustDeclIfTemplate(TagD); 3140 TagDecl *Tag = cast<TagDecl>((Decl *)TagD); 3141 3142 if (isa<CXXRecordDecl>(Tag)) 3143 FieldCollector->FinishClass(); 3144 3145 // Exit this scope of this tag's definition. 3146 PopDeclContext(); 3147 3148 // Notify the consumer that we've defined a tag. 3149 Consumer.HandleTagDeclDefinition(Tag); 3150} 3151 3152/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 3153/// types into constant array types in certain situations which would otherwise 3154/// be errors (for GCC compatibility). 3155static QualType TryToFixInvalidVariablyModifiedType(QualType T, 3156 ASTContext &Context) { 3157 // This method tries to turn a variable array into a constant 3158 // array even when the size isn't an ICE. This is necessary 3159 // for compatibility with code that depends on gcc's buggy 3160 // constant expression folding, like struct {char x[(int)(char*)2];} 3161 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 3162 if (!VLATy) return QualType(); 3163 3164 Expr::EvalResult EvalResult; 3165 if (!VLATy->getSizeExpr() || 3166 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context)) 3167 return QualType(); 3168 3169 assert(EvalResult.Val.isInt() && "Size expressions must be integers!"); 3170 llvm::APSInt &Res = EvalResult.Val.getInt(); 3171 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 3172 return Context.getConstantArrayType(VLATy->getElementType(), 3173 Res, ArrayType::Normal, 0); 3174 return QualType(); 3175} 3176 3177bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3178 QualType FieldTy, const Expr *BitWidth) { 3179 // FIXME: 6.7.2.1p4 - verify the field type. 3180 3181 llvm::APSInt Value; 3182 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3183 return true; 3184 3185 // Zero-width bitfield is ok for anonymous field. 3186 if (Value == 0 && FieldName) 3187 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3188 3189 if (Value.isNegative()) 3190 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) << FieldName; 3191 3192 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3193 // FIXME: We won't need the 0 size once we check that the field type is valid. 3194 if (TypeSize && Value.getZExtValue() > TypeSize) 3195 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3196 << FieldName << (unsigned)TypeSize; 3197 3198 return false; 3199} 3200 3201/// ActOnField - Each field of a struct/union/class is passed into this in order 3202/// to create a FieldDecl object for it. 3203Sema::DeclTy *Sema::ActOnField(Scope *S, DeclTy *TagD, 3204 SourceLocation DeclStart, 3205 Declarator &D, ExprTy *BitfieldWidth) { 3206 IdentifierInfo *II = D.getIdentifier(); 3207 Expr *BitWidth = (Expr*)BitfieldWidth; 3208 SourceLocation Loc = DeclStart; 3209 RecordDecl *Record = (RecordDecl *)TagD; 3210 if (II) Loc = D.getIdentifierLoc(); 3211 3212 // FIXME: Unnamed fields can be handled in various different ways, for 3213 // example, unnamed unions inject all members into the struct namespace! 3214 3215 QualType T = GetTypeForDeclarator(D, S); 3216 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3217 bool InvalidDecl = false; 3218 3219 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3220 // than a variably modified type. 3221 if (T->isVariablyModifiedType()) { 3222 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context); 3223 if (!FixedTy.isNull()) { 3224 Diag(Loc, diag::warn_illegal_constant_array_size); 3225 T = FixedTy; 3226 } else { 3227 Diag(Loc, diag::err_typecheck_field_variable_size); 3228 T = Context.IntTy; 3229 InvalidDecl = true; 3230 } 3231 } 3232 3233 if (BitWidth) { 3234 if (VerifyBitField(Loc, II, T, BitWidth)) 3235 InvalidDecl = true; 3236 } else { 3237 // Not a bitfield. 3238 3239 // validate II. 3240 3241 } 3242 3243 // FIXME: Chain fielddecls together. 3244 FieldDecl *NewFD; 3245 3246 NewFD = FieldDecl::Create(Context, Record, 3247 Loc, II, T, BitWidth, 3248 D.getDeclSpec().getStorageClassSpec() == 3249 DeclSpec::SCS_mutable); 3250 3251 if (II) { 3252 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3253 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3254 && !isa<TagDecl>(PrevDecl)) { 3255 Diag(Loc, diag::err_duplicate_member) << II; 3256 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3257 NewFD->setInvalidDecl(); 3258 Record->setInvalidDecl(); 3259 } 3260 } 3261 3262 if (getLangOptions().CPlusPlus) { 3263 CheckExtraCXXDefaultArguments(D); 3264 if (!T->isPODType()) 3265 cast<CXXRecordDecl>(Record)->setPOD(false); 3266 } 3267 3268 ProcessDeclAttributes(NewFD, D); 3269 3270 if (D.getInvalidType() || InvalidDecl) 3271 NewFD->setInvalidDecl(); 3272 3273 if (II) { 3274 PushOnScopeChains(NewFD, S); 3275 } else 3276 Record->addDecl(NewFD); 3277 3278 return NewFD; 3279} 3280 3281/// TranslateIvarVisibility - Translate visibility from a token ID to an 3282/// AST enum value. 3283static ObjCIvarDecl::AccessControl 3284TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3285 switch (ivarVisibility) { 3286 default: assert(0 && "Unknown visitibility kind"); 3287 case tok::objc_private: return ObjCIvarDecl::Private; 3288 case tok::objc_public: return ObjCIvarDecl::Public; 3289 case tok::objc_protected: return ObjCIvarDecl::Protected; 3290 case tok::objc_package: return ObjCIvarDecl::Package; 3291 } 3292} 3293 3294/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3295/// in order to create an IvarDecl object for it. 3296Sema::DeclTy *Sema::ActOnIvar(Scope *S, 3297 SourceLocation DeclStart, 3298 Declarator &D, ExprTy *BitfieldWidth, 3299 tok::ObjCKeywordKind Visibility) { 3300 3301 IdentifierInfo *II = D.getIdentifier(); 3302 Expr *BitWidth = (Expr*)BitfieldWidth; 3303 SourceLocation Loc = DeclStart; 3304 if (II) Loc = D.getIdentifierLoc(); 3305 3306 // FIXME: Unnamed fields can be handled in various different ways, for 3307 // example, unnamed unions inject all members into the struct namespace! 3308 3309 QualType T = GetTypeForDeclarator(D, S); 3310 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3311 bool InvalidDecl = false; 3312 3313 if (BitWidth) { 3314 // TODO: Validate. 3315 //printf("WARNING: BITFIELDS IGNORED!\n"); 3316 3317 // 6.7.2.1p3 3318 // 6.7.2.1p4 3319 3320 } else { 3321 // Not a bitfield. 3322 3323 // validate II. 3324 3325 } 3326 3327 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3328 // than a variably modified type. 3329 if (T->isVariablyModifiedType()) { 3330 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3331 InvalidDecl = true; 3332 } 3333 3334 // Get the visibility (access control) for this ivar. 3335 ObjCIvarDecl::AccessControl ac = 3336 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3337 : ObjCIvarDecl::None; 3338 3339 // Construct the decl. 3340 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, Loc, II, T, ac, 3341 (Expr *)BitfieldWidth); 3342 3343 if (II) { 3344 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3345 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3346 && !isa<TagDecl>(PrevDecl)) { 3347 Diag(Loc, diag::err_duplicate_member) << II; 3348 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3349 NewID->setInvalidDecl(); 3350 } 3351 } 3352 3353 // Process attributes attached to the ivar. 3354 ProcessDeclAttributes(NewID, D); 3355 3356 if (D.getInvalidType() || InvalidDecl) 3357 NewID->setInvalidDecl(); 3358 3359 if (II) { 3360 // FIXME: When interfaces are DeclContexts, we'll need to add 3361 // these to the interface. 3362 S->AddDecl(NewID); 3363 IdResolver.AddDecl(NewID); 3364 } 3365 3366 return NewID; 3367} 3368 3369void Sema::ActOnFields(Scope* S, 3370 SourceLocation RecLoc, DeclTy *RecDecl, 3371 DeclTy **Fields, unsigned NumFields, 3372 SourceLocation LBrac, SourceLocation RBrac, 3373 AttributeList *Attr) { 3374 Decl *EnclosingDecl = static_cast<Decl*>(RecDecl); 3375 assert(EnclosingDecl && "missing record or interface decl"); 3376 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3377 3378 // Verify that all the fields are okay. 3379 unsigned NumNamedMembers = 0; 3380 llvm::SmallVector<FieldDecl*, 32> RecFields; 3381 3382 for (unsigned i = 0; i != NumFields; ++i) { 3383 FieldDecl *FD = cast_or_null<FieldDecl>(static_cast<Decl*>(Fields[i])); 3384 assert(FD && "missing field decl"); 3385 3386 // Get the type for the field. 3387 Type *FDTy = FD->getType().getTypePtr(); 3388 3389 if (!FD->isAnonymousStructOrUnion()) { 3390 // Remember all fields written by the user. 3391 RecFields.push_back(FD); 3392 } 3393 3394 // C99 6.7.2.1p2 - A field may not be a function type. 3395 if (FDTy->isFunctionType()) { 3396 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3397 << FD->getDeclName(); 3398 FD->setInvalidDecl(); 3399 EnclosingDecl->setInvalidDecl(); 3400 continue; 3401 } 3402 // C99 6.7.2.1p2 - A field may not be an incomplete type except... 3403 if (FDTy->isIncompleteType()) { 3404 if (!Record) { // Incomplete ivar type is always an error. 3405 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3406 diag::err_field_incomplete); 3407 FD->setInvalidDecl(); 3408 EnclosingDecl->setInvalidDecl(); 3409 continue; 3410 } 3411 if (i != NumFields-1 || // ... that the last member ... 3412 !Record->isStruct() || // ... of a structure ... 3413 !FDTy->isArrayType()) { //... may have incomplete array type. 3414 DiagnoseIncompleteType(FD->getLocation(), FD->getType(), 3415 diag::err_field_incomplete); 3416 FD->setInvalidDecl(); 3417 EnclosingDecl->setInvalidDecl(); 3418 continue; 3419 } 3420 if (NumNamedMembers < 1) { //... must have more than named member ... 3421 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3422 << FD->getDeclName(); 3423 FD->setInvalidDecl(); 3424 EnclosingDecl->setInvalidDecl(); 3425 continue; 3426 } 3427 // Okay, we have a legal flexible array member at the end of the struct. 3428 if (Record) 3429 Record->setHasFlexibleArrayMember(true); 3430 } 3431 /// C99 6.7.2.1p2 - a struct ending in a flexible array member cannot be the 3432 /// field of another structure or the element of an array. 3433 if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3434 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3435 // If this is a member of a union, then entire union becomes "flexible". 3436 if (Record && Record->isUnion()) { 3437 Record->setHasFlexibleArrayMember(true); 3438 } else { 3439 // If this is a struct/class and this is not the last element, reject 3440 // it. Note that GCC supports variable sized arrays in the middle of 3441 // structures. 3442 if (i != NumFields-1) { 3443 Diag(FD->getLocation(), diag::err_variable_sized_type_in_struct) 3444 << FD->getDeclName(); 3445 FD->setInvalidDecl(); 3446 EnclosingDecl->setInvalidDecl(); 3447 continue; 3448 } 3449 // We support flexible arrays at the end of structs in other structs 3450 // as an extension. 3451 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3452 << FD->getDeclName(); 3453 if (Record) 3454 Record->setHasFlexibleArrayMember(true); 3455 } 3456 } 3457 } 3458 /// A field cannot be an Objective-c object 3459 if (FDTy->isObjCInterfaceType()) { 3460 Diag(FD->getLocation(), diag::err_statically_allocated_object) 3461 << FD->getDeclName(); 3462 FD->setInvalidDecl(); 3463 EnclosingDecl->setInvalidDecl(); 3464 continue; 3465 } 3466 // Keep track of the number of named members. 3467 if (FD->getIdentifier()) 3468 ++NumNamedMembers; 3469 } 3470 3471 // Okay, we successfully defined 'Record'. 3472 if (Record) { 3473 Record->completeDefinition(Context); 3474 } else { 3475 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3476 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3477 ID->addInstanceVariablesToClass(ClsFields, RecFields.size(), RBrac); 3478 // Must enforce the rule that ivars in the base classes may not be 3479 // duplicates. 3480 if (ID->getSuperClass()) { 3481 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3482 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3483 ObjCIvarDecl* Ivar = (*IVI); 3484 IdentifierInfo *II = Ivar->getIdentifier(); 3485 ObjCIvarDecl* prevIvar = ID->getSuperClass()->FindIvarDeclaration(II); 3486 if (prevIvar) { 3487 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3488 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3489 } 3490 } 3491 } 3492 } 3493 else if (ObjCImplementationDecl *IMPDecl = 3494 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3495 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3496 IMPDecl->ObjCAddInstanceVariablesToClassImpl(ClsFields, RecFields.size()); 3497 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3498 } 3499 } 3500 3501 if (Attr) 3502 ProcessDeclAttributeList(Record, Attr); 3503} 3504 3505Sema::DeclTy *Sema::ActOnEnumConstant(Scope *S, DeclTy *theEnumDecl, 3506 DeclTy *lastEnumConst, 3507 SourceLocation IdLoc, IdentifierInfo *Id, 3508 SourceLocation EqualLoc, ExprTy *val) { 3509 EnumDecl *TheEnumDecl = cast<EnumDecl>(static_cast<Decl*>(theEnumDecl)); 3510 EnumConstantDecl *LastEnumConst = 3511 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(lastEnumConst)); 3512 Expr *Val = static_cast<Expr*>(val); 3513 3514 // The scope passed in may not be a decl scope. Zip up the scope tree until 3515 // we find one that is. 3516 S = getNonFieldDeclScope(S); 3517 3518 // Verify that there isn't already something declared with this name in this 3519 // scope. 3520 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 3521 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3522 // Maybe we will complain about the shadowed template parameter. 3523 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 3524 // Just pretend that we didn't see the previous declaration. 3525 PrevDecl = 0; 3526 } 3527 3528 if (PrevDecl) { 3529 // When in C++, we may get a TagDecl with the same name; in this case the 3530 // enum constant will 'hide' the tag. 3531 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 3532 "Received TagDecl when not in C++!"); 3533 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 3534 if (isa<EnumConstantDecl>(PrevDecl)) 3535 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 3536 else 3537 Diag(IdLoc, diag::err_redefinition) << Id; 3538 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3539 Val->Destroy(Context); 3540 return 0; 3541 } 3542 } 3543 3544 llvm::APSInt EnumVal(32); 3545 QualType EltTy; 3546 if (Val) { 3547 // Make sure to promote the operand type to int. 3548 UsualUnaryConversions(Val); 3549 3550 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 3551 SourceLocation ExpLoc; 3552 if (VerifyIntegerConstantExpression(Val, &EnumVal)) { 3553 Val->Destroy(Context); 3554 Val = 0; // Just forget about it. 3555 } else { 3556 EltTy = Val->getType(); 3557 } 3558 } 3559 3560 if (!Val) { 3561 if (LastEnumConst) { 3562 // Assign the last value + 1. 3563 EnumVal = LastEnumConst->getInitVal(); 3564 ++EnumVal; 3565 3566 // Check for overflow on increment. 3567 if (EnumVal < LastEnumConst->getInitVal()) 3568 Diag(IdLoc, diag::warn_enum_value_overflow); 3569 3570 EltTy = LastEnumConst->getType(); 3571 } else { 3572 // First value, set to zero. 3573 EltTy = Context.IntTy; 3574 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 3575 } 3576 } 3577 3578 EnumConstantDecl *New = 3579 EnumConstantDecl::Create(Context, TheEnumDecl, IdLoc, Id, EltTy, 3580 Val, EnumVal); 3581 3582 // Register this decl in the current scope stack. 3583 PushOnScopeChains(New, S); 3584 3585 return New; 3586} 3587 3588// FIXME: For consistency with ActOnFields(), we should have the parser 3589// pass in the source location for the left/right braces. 3590void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclTy *EnumDeclX, 3591 DeclTy **Elements, unsigned NumElements) { 3592 EnumDecl *Enum = cast<EnumDecl>(static_cast<Decl*>(EnumDeclX)); 3593 QualType EnumType = Context.getTypeDeclType(Enum); 3594 3595 // TODO: If the result value doesn't fit in an int, it must be a long or long 3596 // long value. ISO C does not support this, but GCC does as an extension, 3597 // emit a warning. 3598 unsigned IntWidth = Context.Target.getIntWidth(); 3599 3600 // Verify that all the values are okay, compute the size of the values, and 3601 // reverse the list. 3602 unsigned NumNegativeBits = 0; 3603 unsigned NumPositiveBits = 0; 3604 3605 // Keep track of whether all elements have type int. 3606 bool AllElementsInt = true; 3607 3608 for (unsigned i = 0; i != NumElements; ++i) { 3609 EnumConstantDecl *ECD = 3610 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3611 if (!ECD) continue; // Already issued a diagnostic. 3612 3613 // If the enum value doesn't fit in an int, emit an extension warning. 3614 const llvm::APSInt &InitVal = ECD->getInitVal(); 3615 assert(InitVal.getBitWidth() >= IntWidth && 3616 "Should have promoted value to int"); 3617 if (InitVal.getBitWidth() > IntWidth) { 3618 llvm::APSInt V(InitVal); 3619 V.trunc(IntWidth); 3620 V.extend(InitVal.getBitWidth()); 3621 if (V != InitVal) 3622 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 3623 << InitVal.toString(10); 3624 } 3625 3626 // Keep track of the size of positive and negative values. 3627 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 3628 NumPositiveBits = std::max(NumPositiveBits, 3629 (unsigned)InitVal.getActiveBits()); 3630 else 3631 NumNegativeBits = std::max(NumNegativeBits, 3632 (unsigned)InitVal.getMinSignedBits()); 3633 3634 // Keep track of whether every enum element has type int (very commmon). 3635 if (AllElementsInt) 3636 AllElementsInt = ECD->getType() == Context.IntTy; 3637 } 3638 3639 // Figure out the type that should be used for this enum. 3640 // FIXME: Support attribute(packed) on enums and -fshort-enums. 3641 QualType BestType; 3642 unsigned BestWidth; 3643 3644 if (NumNegativeBits) { 3645 // If there is a negative value, figure out the smallest integer type (of 3646 // int/long/longlong) that fits. 3647 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 3648 BestType = Context.IntTy; 3649 BestWidth = IntWidth; 3650 } else { 3651 BestWidth = Context.Target.getLongWidth(); 3652 3653 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 3654 BestType = Context.LongTy; 3655 else { 3656 BestWidth = Context.Target.getLongLongWidth(); 3657 3658 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 3659 Diag(Enum->getLocation(), diag::warn_enum_too_large); 3660 BestType = Context.LongLongTy; 3661 } 3662 } 3663 } else { 3664 // If there is no negative value, figure out which of uint, ulong, ulonglong 3665 // fits. 3666 if (NumPositiveBits <= IntWidth) { 3667 BestType = Context.UnsignedIntTy; 3668 BestWidth = IntWidth; 3669 } else if (NumPositiveBits <= 3670 (BestWidth = Context.Target.getLongWidth())) { 3671 BestType = Context.UnsignedLongTy; 3672 } else { 3673 BestWidth = Context.Target.getLongLongWidth(); 3674 assert(NumPositiveBits <= BestWidth && 3675 "How could an initializer get larger than ULL?"); 3676 BestType = Context.UnsignedLongLongTy; 3677 } 3678 } 3679 3680 // Loop over all of the enumerator constants, changing their types to match 3681 // the type of the enum if needed. 3682 for (unsigned i = 0; i != NumElements; ++i) { 3683 EnumConstantDecl *ECD = 3684 cast_or_null<EnumConstantDecl>(static_cast<Decl*>(Elements[i])); 3685 if (!ECD) continue; // Already issued a diagnostic. 3686 3687 // Standard C says the enumerators have int type, but we allow, as an 3688 // extension, the enumerators to be larger than int size. If each 3689 // enumerator value fits in an int, type it as an int, otherwise type it the 3690 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 3691 // that X has type 'int', not 'unsigned'. 3692 if (ECD->getType() == Context.IntTy) { 3693 // Make sure the init value is signed. 3694 llvm::APSInt IV = ECD->getInitVal(); 3695 IV.setIsSigned(true); 3696 ECD->setInitVal(IV); 3697 3698 if (getLangOptions().CPlusPlus) 3699 // C++ [dcl.enum]p4: Following the closing brace of an 3700 // enum-specifier, each enumerator has the type of its 3701 // enumeration. 3702 ECD->setType(EnumType); 3703 continue; // Already int type. 3704 } 3705 3706 // Determine whether the value fits into an int. 3707 llvm::APSInt InitVal = ECD->getInitVal(); 3708 bool FitsInInt; 3709 if (InitVal.isUnsigned() || !InitVal.isNegative()) 3710 FitsInInt = InitVal.getActiveBits() < IntWidth; 3711 else 3712 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 3713 3714 // If it fits into an integer type, force it. Otherwise force it to match 3715 // the enum decl type. 3716 QualType NewTy; 3717 unsigned NewWidth; 3718 bool NewSign; 3719 if (FitsInInt) { 3720 NewTy = Context.IntTy; 3721 NewWidth = IntWidth; 3722 NewSign = true; 3723 } else if (ECD->getType() == BestType) { 3724 // Already the right type! 3725 if (getLangOptions().CPlusPlus) 3726 // C++ [dcl.enum]p4: Following the closing brace of an 3727 // enum-specifier, each enumerator has the type of its 3728 // enumeration. 3729 ECD->setType(EnumType); 3730 continue; 3731 } else { 3732 NewTy = BestType; 3733 NewWidth = BestWidth; 3734 NewSign = BestType->isSignedIntegerType(); 3735 } 3736 3737 // Adjust the APSInt value. 3738 InitVal.extOrTrunc(NewWidth); 3739 InitVal.setIsSigned(NewSign); 3740 ECD->setInitVal(InitVal); 3741 3742 // Adjust the Expr initializer and type. 3743 if (ECD->getInitExpr()) 3744 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 3745 /*isLvalue=*/false)); 3746 if (getLangOptions().CPlusPlus) 3747 // C++ [dcl.enum]p4: Following the closing brace of an 3748 // enum-specifier, each enumerator has the type of its 3749 // enumeration. 3750 ECD->setType(EnumType); 3751 else 3752 ECD->setType(NewTy); 3753 } 3754 3755 Enum->completeDefinition(Context, BestType); 3756} 3757 3758Sema::DeclTy *Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 3759 ExprArg expr) { 3760 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 3761 3762 return FileScopeAsmDecl::Create(Context, CurContext, Loc, AsmString); 3763} 3764 3765 3766void Sema::ActOnPragmaPack(PragmaPackKind Kind, IdentifierInfo *Name, 3767 ExprTy *alignment, SourceLocation PragmaLoc, 3768 SourceLocation LParenLoc, SourceLocation RParenLoc) { 3769 Expr *Alignment = static_cast<Expr *>(alignment); 3770 3771 // If specified then alignment must be a "small" power of two. 3772 unsigned AlignmentVal = 0; 3773 if (Alignment) { 3774 llvm::APSInt Val; 3775 if (!Alignment->isIntegerConstantExpr(Val, Context) || 3776 !Val.isPowerOf2() || 3777 Val.getZExtValue() > 16) { 3778 Diag(PragmaLoc, diag::warn_pragma_pack_invalid_alignment); 3779 Alignment->Destroy(Context); 3780 return; // Ignore 3781 } 3782 3783 AlignmentVal = (unsigned) Val.getZExtValue(); 3784 } 3785 3786 switch (Kind) { 3787 case Action::PPK_Default: // pack([n]) 3788 PackContext.setAlignment(AlignmentVal); 3789 break; 3790 3791 case Action::PPK_Show: // pack(show) 3792 // Show the current alignment, making sure to show the right value 3793 // for the default. 3794 AlignmentVal = PackContext.getAlignment(); 3795 // FIXME: This should come from the target. 3796 if (AlignmentVal == 0) 3797 AlignmentVal = 8; 3798 Diag(PragmaLoc, diag::warn_pragma_pack_show) << AlignmentVal; 3799 break; 3800 3801 case Action::PPK_Push: // pack(push [, id] [, [n]) 3802 PackContext.push(Name); 3803 // Set the new alignment if specified. 3804 if (Alignment) 3805 PackContext.setAlignment(AlignmentVal); 3806 break; 3807 3808 case Action::PPK_Pop: // pack(pop [, id] [, n]) 3809 // MSDN, C/C++ Preprocessor Reference > Pragma Directives > pack: 3810 // "#pragma pack(pop, identifier, n) is undefined" 3811 if (Alignment && Name) 3812 Diag(PragmaLoc, diag::warn_pragma_pack_pop_identifer_and_alignment); 3813 3814 // Do the pop. 3815 if (!PackContext.pop(Name)) { 3816 // If a name was specified then failure indicates the name 3817 // wasn't found. Otherwise failure indicates the stack was 3818 // empty. 3819 Diag(PragmaLoc, diag::warn_pragma_pack_pop_failed) 3820 << (Name ? "no record matching name" : "stack empty"); 3821 3822 // FIXME: Warn about popping named records as MSVC does. 3823 } else { 3824 // Pop succeeded, set the new alignment if specified. 3825 if (Alignment) 3826 PackContext.setAlignment(AlignmentVal); 3827 } 3828 break; 3829 3830 default: 3831 assert(0 && "Invalid #pragma pack kind."); 3832 } 3833} 3834 3835bool PragmaPackStack::pop(IdentifierInfo *Name) { 3836 if (Stack.empty()) 3837 return false; 3838 3839 // If name is empty just pop top. 3840 if (!Name) { 3841 Alignment = Stack.back().first; 3842 Stack.pop_back(); 3843 return true; 3844 } 3845 3846 // Otherwise, find the named record. 3847 for (unsigned i = Stack.size(); i != 0; ) { 3848 --i; 3849 if (Stack[i].second == Name) { 3850 // Found it, pop up to and including this record. 3851 Alignment = Stack[i].first; 3852 Stack.erase(Stack.begin() + i, Stack.end()); 3853 return true; 3854 } 3855 } 3856 3857 return false; 3858} 3859